To what extent is alcohol consumption associated with breast cancer recurrence and second primary breast cancer?: A systematic review

Cancer Treatment Reviews 50 (2016) 155–167

Contents lists available at ScienceDirect

Cancer Treatment Reviews journal homepage: www.elsevierhealth.com/journals/ctrv

Systematic or Meta-analysis Studies

To what extent is alcohol consumption associated with breast cancer recurrence and second primary breast cancer?: A systematic review Phanthira Simapivapan a, Anna Boltong b,⇑, Allison Hodge b a b

The University of Melbourne, Parkville, Victoria 3010, Australia Cancer Council Victoria, 615 St Kilda Road, Melbourne, Victoria 3004, Australia

a r t i c l e

i n f o

Article history: Received 1 July 2016 Received in revised form 10 September 2016 Accepted 12 September 2016

Keywords: Alcohol Breast cancer Recurrence Second primary Breast cancer survivor

a b s t r a c t Background: The association between alcohol intake and breast cancer recurrence or development of second primary breast cancer in the survivor population is unclear. The aim of this systematic review was to evaluate the existing evidence to assess the extent to which alcohol consumption is associated with breast cancer recurrence and second primary breast cancer. Methods: Six databases (Cochrane Library, EMBASE, MEDLINE, PubMed, Scopus and Web of Science) were searched using the following search phrase: (breast cancer OR breast adenocarcinoma OR breast neoplasm OR breast tumour) AND (alcohol⁄ OR alcohol intake OR alcohol consumption OR ethanol) AND (recurrence OR second primary). A narrative synthesis was conducted on studies meeting the inclusion criteria. Results: After screening, 16 studies met the inclusion criteria, of which 11 assessed breast cancer recurrence and 5 assessed second primary breast cancer. Considerable clinical and methodological heterogeneity was observed between studies. Approximately half of the included studies observed a modest, but significant, association between alcohol consumption and increased risk of breast cancer recurrence or development of a second primary breast cancer, with some studies observing associations from as little as six grams of alcohol intake per day. Two studies suggest this association was stronger in postmenopausal women. Conclusion: There is some evidence that alcohol consumption increases the risk of breast cancer recurrence, particularly in postmenopausal women. The association between alcohol and development of a second primary breast cancer is less clear. Inconsistencies in methodology and results across studies complicate attempts to develop a cohesive interpretation of findings. Ó 2016 Elsevier Ltd. All rights reserved.

Introduction Breast cancer is the most common type of cancer affecting women worldwide, with almost 1.7 million new cases diagnosed in 2012 alone [1]. With breast cancer survival rates continuing to improve, there has been increasing interest in the role of modifiable lifestyle factors relating to disease incidence and mortality. The link between alcohol consumption and risk of primary breast cancer has been extensively researched, with most recent literature supporting a linear dose–response relationship where each additional standard drink per day consumed is estimated to increase breast cancer risk by 2–12% [2–4]. Reducing alcohol intake is therefore considered important in primary breast cancer preven-

⇑ Corresponding author. E-mail address: [email protected] (A. Boltong). http://dx.doi.org/10.1016/j.ctrv.2016.09.010 0305-7372/Ó 2016 Elsevier Ltd. All rights reserved.

tion, and indeed significant public health education and awareness efforts have leveraged this link [5]. What then does this mean for people who have already been diagnosed with breast cancer? Of women who have undergone breast conserving surgery and radiotherapy, 12–15% will develop a local recurrence within 10 years [6,7]. Fear of recurrence is an issue that ranks consistently high on the list of patient reported worries in the post-treatment phase, as does a lack of medical advice that is specific to survivors [8]. Advice sought regarding appropriate levels of alcohol intake requires health care practitioners to interpret public health recommendations at the personal level [9]. In order to best guide recommendations regarding alcohol intake in the survivorship phase, this systematic review aimed to gather all literature investigating the association between alcohol consumption and breast cancer recurrence or second primary breast cancer to assess the extent to which alcohol consumption

156

P. Simapivapan et al. / Cancer Treatment Reviews 50 (2016) 155–167

Table 1 Inclusion/exclusion criteria with corresponding exclusion code. Selection question Is this an article representing original data or secondary data manipulated in an original way? If no, code as EC1 Is this a study of human participants? If no, code as EC2 Is this a study of adult participants (aged >18 years)? If no, code as EC3 Does this study investigate participants who have been previously diagnosed with and treated for breast cancer? If no, code as EC4 Does this study investigate alcohol consumption in participants? If no, code as EC5 Does this study investigate alcohol consumption in relation to risk of breast cancer recurrence or second primary breast cancer? If no, code as EC6

Inclusion

Exclusion

Exclusion code

Article represents original data or secondary data analysed using an original analytical method Human participants

Article is a letter, case study or review of existing studies

EC1

Non-human participants

EC2

Study of participants >18 years of age

Study participants <18 years of age

EC3

Study investigates participants previously diagnosed with and treated for breast cancer

Study investigates participants who have not been previously diagnosed with breast cancer

EC4

Study investigates alcohol consumption in participants

Study does not investigate alcohol consumption in participants

EC5

Study investigates alcohol consumption in relation to risk of breast cancer recurrence or second primary breast cancer

Study investigates alcohol consumption, but does not EC6 explore its relation to breast cancer recurrence or second primary breast cancer

is associated with these outcomes amongst breast cancer survivors. Methods The reporting of this systematic review is consistent with the PRISMA statement [10]. A protocol outlining the methods for literature search, study selection and data synthesis was registered on the PROSPERO database http://www.crd.york.ac.uk/PROSPERO/ on 3 March 2016 with reference number CRD42016036041. Literature search and sources The following databases were searched for English language peer-reviewed publications in January 2016: Cochrane Library, EMBASE, MEDLINE, PubMed, Scopus and Web of Science. No date restrictions were applied. The following search phrase was used: (breast cancer OR breast adenocarcinoma OR breast neoplasm OR breast tumour) AND (alcohol⁄ OR alcohol intake OR alcohol consumption OR ethanol) AND (recurrence OR second primary). ‘Second primary’ was a term specifically added to the search phrase after it became apparent that the term ‘recurrence’ was intended by some authors to include second primary breast cancer. Reference lists of publications identified to be relevant to this systematic review were also hand searched for potentially eligible articles. Study selection After compiling the search results from the aforementioned databases, duplicate papers were identified and removed. Titles and abstracts were screened, and inclusion and exclusion criteria applied independently by two reviewers (PS, AB). Peer-reviewed, English language articles were eligible for inclusion if they reported findings from studies using original data or secondary data with original analyses involving adult (age P18 years) human participants. For publications deemed potentially eligible, full text copies were retrieved and read in full to determine whether the inclusion criteria were met. Agreed reasons for exclusion were recorded. Included studies investigated alcohol consumption in relation to breast cancer recurrence or development of second primary breast cancer in women previously diagnosed with breast cancer. Because our review did not utilise a meta-analytic

approach, it was agreed that two pooled studies [11,12] would be included. These studies benefited from an increased sample size and longer follow up periods. Nechuta et al. [12] was the first study to investigate late breast cancer recurrence in ER + participants specifically. Refer to Table 1 for detailed inclusion/exclusion criteria. Data extraction Data regarding authorship, study design, sample characteristics, method of recruitment, duration of study follow-up, measures of pre and post-diagnosis alcohol exposure and outcome were extracted. Outcome measures of interest were: (1) new onset of breast cancer recurrence or (2) new onset of second primary breast cancer. Where multiple analyses were performed adjusting for different confounding factors (e.g. age, BMI, stage of initial breast cancer), only effect estimates adjusting for the widest range of appropriate confounders were extracted. Extraction of data from included studies was performed by one reviewer (PS), with subsequent revision of the completed data set in reference to the original papers by two other reviewers (AB and AH) for accuracy and consistency. Quality assessment The quality of each included study was assessed using the Newcastle-Ottawa Scale for non-randomised studies [13]. This tool allows the scale to be modified to best address the parameters of review across three main study characteristics: selection of study groups, comparability of selected groups, and methods of assessing alcohol exposure and defining cancer status. A star was allocated for every study design characteristic deemed to be high quality, with a potential maximum allocation of 9 stars for each study. Quality assessment was performed by one reviewer (PS), with subsequent revision by two reviewers (AB, AH). Refer to Supplementary Appendix A for the modified version of the scale used. Data synthesis A narrative synthesis of results was used, rather than a metaanalytic approach, due to the high level of clinical and methodological heterogeneity between studies, particularly in the aspects of

P. Simapivapan et al. / Cancer Treatment Reviews 50 (2016) 155–167

exposure subgroups, exposure assessment methods and outcome definitions. Primary study methods included participant recruitment, exposure and outcome assessment, exposure subgroups, and outcome definition. These methods were appraised in each of the included studies and contrasted against one another, with critical qualitative analysis of how such methods may have contributed to the reported effect estimates. Studies assessing breast cancer recurrence were analysed separately to those assessing second primary breast cancer. In accordance with Cochrane protocol [14], tests for detecting reporting bias were not conducted due to the small number of included studies (<10 separate studies per analysis group), the high level of heterogeneity between these studies, and subsequent low power of the tests in these circumstances. Results Literature search results After filtering for English language publications and subsequent removal of duplicates, a total of 314 articles were screened via evaluation of titles and abstracts, resulting in exclusion of 289 articles. Review of full text copies led to further exclusion of nine articles, leaving a final total of 16 publications (5%) that met the

157

inclusion criteria. Of the included articles, 11 were identified as assessing breast cancer recurrence [11,12,15–23], and five were identified as assessing second primary breast cancer [24–28]. Refer to Fig. 1 for a PRISMA flow diagram of the selection process. Overview of included studies Table 2 presents an overview of the characteristics of the included studies. All studies meeting the inclusion criteria were observational, with 14 being cohort studies [11,12,15–25,27] and two, case-control studies [16,18]. Dates of publication ranged between 1998 and 2015. Of these articles, 14 contained primary data, and two studies [11,12] utilised data from the After Breast Cancer Pooling Project (ABCPP), which pools data from three individual cohort studies (WHEL [21], LACE [20], and NHS). Two of these studies (WHEL and LACE) are also included separately in this review. There were no previous publications on alcohol consumption and breast cancer recurrence from the NHS cohort prior to these pooled studies. The 16 studies included in this systematic review present data from 35,690 participants. Participants comprised adult (P18 years) women diagnosed with first carcinoma in situ or invasive breast cancer (TNM stages 0-IV). Participants were assessed for alcohol intake and followed for between 5 and 18 years from the time of their first breast cancer diagnosis until recurrence,

Fig. 1. PRISMA flow diagram depicting the main stages of the systematic review selection process.

158

Table 2 Characteristics of included studies. Length of follow-up Sample Cohort size (n)

Country

Study design

Data collection period

Breast cancer recurrence Hebert et al. (1998) [15] Saxe et al. (1999) [16] Muscat et al. (2003) [17]

USA USA USA

Prospective cohort Prospective cohort Prospective cohort

Brewster et al. (2007) [18] Flatt et al. (2010) [21] Kwan et al. (2010) [20]

USA USA USA

Prospective cohort Prospective cohort Prospective cohort

Vrieling et al. (2012) [19]

Germany Prospective cohort

Holm et al. (2013) [22]

Denmark Prospective cohort

McLaughlin et al. (2014) [23]

USA

Prospective cohort

1982–1991 8–10 years 1989-NS 5 or more years 1994–2001 5 years (Mean = 3.6 years) 1985–2005 5 years 1991–2006 Median = 7.3 years 1997–2009 0.1–9.6 years (Mean = 7.4 years) 2001–2009 4.4–7.4 years (Median = 5.5 years) 1993–2008 1.7–12.1 years (Median = 6 years) 1997–2011 0.4–15.3 years (Mean = 6.7 years)

USA USA

Pooled cohort Pooled cohort

USA

Prospective cohort

Breast cancer recurrence (pooled) Kwan et al. (2013) [11] Nechuta et al. (2015) [12] Second primary breast cancer Bernstein et al. (1992) [24] Li et al. (2003) [25]

USA

Trentham-Dietz et al. (2007) [27] USA Knight et al. (2009) [28] Li et al. (2009) [26]

USA USA

1990-NS 1990-NS

471 149 224

MSKCC MC-UoM LIJMC-NSUH

20–80 26–95 (57.8) NS

TNM stage I, II, or IIIa breast cancer with single breast involvement Any primary breast cancer (stage 0, I, II, III, or IV) TNM stage 0 (carcinoma in situ), I, II, or III breast cancer

2,327 3,088 1,897

ESBCR WHEL LACE

(55) 18–70 (52) 18–70

TNM stage I or II breast cancer TNM stage I, II, or IIIa breast cancer TNM stage I, II, or IIIa breast cancer

2,184

MARIE

50–74

TNM stage I, II, or IIIa breast cancer

1,028

DCH

53–71

TNM stage I, II or III breast cancer

1,925

WISC

20–74

Ductal carcinoma in situ only (stage 0)

Mean = 10.3 years 9,151 Median = 10.6 years 5,675

1980–1986 4–6 years (Mean = 4.3 years) Prospective cohort 1983–2001 0.5–18.1 years (Mean = 9 years) Retrospective cohort 1987–2002 1–14 years (Mean = 7.1 years) Case-control 1985–2001 N/A Case-control 1990–2007 N/A

Age at diagnosis Cancer types/stages range (mean)

ABCPP (WHEL, LACE, NHS) 20–83 (58.8) ABCPP (WHEL, LACE, NHS) 20–83 (59.4)

TNM stage I, II, or III breast cancer TNM stage I, II, or III breast cancer

2,819

CSHS

20–54 (44.3)

Any primary breast cancer (stage 0, I, II, III, or IV)

1,285

KPSC-WS, ASNJ

20–44 (37.7)

Any primary invasive breast cancer (stage I, II, III, or IV)

10,953 WTR

18–79 (59.4)

Any primary invasive breast cancer (stage I, II, III, or IV)

2,107 1,067

23–55 40–79

TNM stage I, II or III breast cancer TNM stage I, II, IIIa, or IIIb ER + breast cancer

WECARE SPSR

Abbreviations: NS = not specified; MSKCC = Memorial Sloan-Kettering Cancer Center; MC-UoM = Medical Center – University of Michigan; LIJMC-NSUH = Long Island Jewish Medical Center – North Shore University Hospital; ESBCR = Early Stage Breast Cancer Repository; WHEL = Women’s Healthy Eating and Living; LACE = Life After Cancer Epidemiology; MARIE = Mamma Carcinoma Risk Factor Investigation; DCH = Diet, Cancer and Health; WISC = Wisconsin In Situ Cohort; ABCPP = After Breast Cancer Pooling Project; NHS = Nurses’ Health Study; N/A = not applicable; CSHS = Cancer and Steroid Hormone Study; KPSC-WS = King, Pierce, Snohomish County – Washington State; ASNJ = Atlanta, Seattle, New Jersey; WTR = Wisconsin tumour registry; WECARE = Women’s Environmental Cancer and Radiation Epidemiology; SPSR = Seattle-Puget Sound Region.

P. Simapivapan et al. / Cancer Treatment Reviews 50 (2016) 155–167

Study

Table 3 Methodological quality of included studies.a Study

Case-control studies Knight et al. (2009) Li et al. (2009)

Representativeness of the exposed cohort

Selection of the nonexposed cohort

Method of assessing alcohol exposure

Demonstration that outcome of interest was not present at start of study

Comparability of cohorts on the basis of design or analysisb

Method of defining cancer status

Follow up long enough for outcomes to occur

Adequacy of follow up of cohorts

Casecontrol study criteria

Representativeness of the cases

Selection of controls

Is the case definition adequate?

Definition of controls

Comparability of cases and controls on the basis of design or analysisb

Method of assessing alcohol exposure

Same method of assessing for cases and controls

Non-response rate

Total score – quality

8 7 5 7 8 8 8 8 6

– – – – – – – – –

high fair low fair high high high high fair

7 – fair 7 – fair 8 – High 7 – fair 7 – fair

P. Simapivapan et al. / Cancer Treatment Reviews 50 (2016) 155–167

Cohort studies Breast cancer recurrence Hebert et al. (1998) Saxe et al. (1999) Muscat et al. (2003) Brewster et al. (2007) Flatt et al. (2010) Kwan et al. (2010) Vrieling et al. (2012) Holm et al. (2013) McLaughlin et al. (2014) Breast cancer recurrence (pooled) Kwan et al. (2013) Nechuta et al. (2015) Second primary breast cancer Bernstein et al. (1992) Li et al. (2003) Trentham-Dietz et al. (2007)

Cohort study criteria

6 – fair 8 – high

a A star was allocated for every high quality study design characteristic, with a potential maximum of 9 stars for each given study. High-quality studies were defined as studies achieving 8 or more stars, fair-quality studies achieving 6–7 stars, and poor-quality studies achieving 5 or fewer stars. A study was awarded a maximum of one star for each item except for ‘‘Comparability of cohorts”, for which a maximum of two stars was awarded. b A maximum of two stars was awarded for this item – studies that adjusted for age, TNM stage and BMI received one star, whereas studies that adjusted for additional factors (e.g. PR status, menopausal status) received an additional star.

159

Study

Alcohol assessment methodology

160

Table 4 Alcohol exposure and outcome measures of included studies Unit of measurement

Breast cancer recurrence Hebert et al. (1998) Participants interviewed using a Beer intake (12oz [15] study-specific FFQ drinks/day) Saxe et al. (1999) [16] Participants interviewed using a Drinks/week validated FFQ by the National Cancer Institute Muscat et al. (2003) Participants interviewed using a Drinks/day [17] study-specific questionnaire

Brewster et al. (2007) [18]

Grams/month Participants completed a validated FFQ (The Arizona Food Frequency Questionnaire) and a set of four 24hr recalls by phone interview Grams/day Kwan et al. (2010) [20] Participants completed a validated FFQ (Fred Hutchinson Cancer Research Center Food Questionnaire) Wine servings/week (I serving = 13.7 g alcohol) Flatt et al. (2010) [21]

Grams/day Patients completed a selfadministered FFQ stated to be comparable to another validated FFQ Holm et al. (2013) [22] Participants completed a selfUnit/day administered validated Danish (1 unit = 10 g alcohol) FFQ Vrieling et al. (2012) [19]

Alcohol exposure

Cohort effect estimate Primary outcome

Pre

Beer intake (per 12oz drinks/day)

RR = 1.41 (1.02–1.97) Breast cancer recurrence (no further details)

Pre

Alcohol (per 2 drinks/week) HR = 0.82 (0.54–1.25)

Pre

Alcohol (<1 drink/day)

RR = 1.0

Alcohol (P1 drink/day)

RR = 0.3 (0.04–2.3)

Alcohol consumption: Never/rare (NS) Moderate (NS) Heavy (NS) Minimal intake (<10 g/mo) Light intake (10–290 g/mo) Moderate/heavy intake (>300 g/mo)

HR = 1.0 HR = 1.03 HR = 0.98 HR = 1.00 HR = 0.89 HR = 0.91

Pre

Post

Post

Pre

Pre

Drinking years

McLaughlin et al. (2014) [23]

Drinks/week Participants completed telephone interviews and mailed surveys at study enrolment and biennially after enrolment

Pre & Post

(0.77–1.38) (0.54–1.80) (0.73-1.08) (0.71–1.18)

Beer associated with increased risk of breast cancer recurrence No association between Breast cancer recurrence (local, regional, metastases) alcohol and breast cancer recurrence Breast cancer recurrence No association between (local, regional, metastases) alcohol and breast cancer *Not including contralateral recurrence breast cancer No association between Breast cancer recurrence (local, regional, metastases, alcohol and breast cancer recurrence including contralateral breast) No association between Invasive breast cancer recurrence or new primary alcohol and breast cancer recurrence breast cancer

Regular consumption of three to four drinks per week associated with increased risk of recurrence, particularly in postmenopausal women and overweight/obese women No association between Breast cancer recurrence (local, regional, metastases, alcohol and breast cancer recurrence including contralateral breast) Modest significant positive Any type of breast cancer association between high subsequent to the initial (>2 units/day, >40 drinking course of therapy years) pre-diagnostic alcohol consumption and breast cancer recurrence among women with early stage breast cancer Risk estimates for Any second breast cancer event (in situ or invasive) individual categories of alcohol intake did not reach including contralateral statistical significance, but a events and events of significant linear trend of unknown laterality increasing risk of any second breast cancer diagnosis was observed over the categories of increasing post-diagnosis alcohol intake (p = 0.02)

Total alcohol: None <6 g/d P6 g/d Wine: 61 serving/week P2 servings/week

Breast cancer recurrence HR = 1.0 (local, regional, metastases, HR = 1.05 (0.78–1.42) including contralateral HR = 1.35 (1.00–1.83) breast)

<0.5 g/d 0.5–<6.0 g/d P6.0–<12.0 g/d P12.0 g/d Baseline intake: 61 unit/day >1 unit/day to 62 units/day >2 units/day Drinking years: 0–10 >10–40 >40 Pre-diagnosis alcohol: No alcohol >0–<2 drinks/week 2– <7 drinks/week >7 drinks/week Post-diagnosis alcohol: No alcohol >0–<2 drinks/week 2–<7 drinks/week >7 drinks/week

HR = 1.0 HR = 1.03 (0.74–1.44) HR = 0.86 (0.54–1.36) HR = 1.08 (0.73–1.58)

HR = 1.01 (0.75–1.36 HR = 1.33 (0.97–1.81)

HR = 1.00 HR = 1.31 (0.81–2.11) HR = 1.65 (1.02–2.67) HR = 1.00 HR = 1.34 (0.74–2.42) HR = 2.02 (1.06–3.85) HR = 1.00 HR = 0.98 (0.62–1.53) HR = 0.91 (0.54–1.53) HR = 1.04 (0.58–1.88) HR = 1.00 HR = 1.28 (0.59–2.78) HR = 1.76 (0.64–4.80) HR = 2.59 (0.61–11.0)

Study conclusion

P. Simapivapan et al. / Cancer Treatment Reviews 50 (2016) 155–167

Categorical Information extracted from medical records based on breast measurement of frequency cancer risk assessment forms

Pre or post diagnosis exposure

Table 4 (continued) Study

Alcohol assessment methodology

Pre or post diagnosis exposure

Alcohol exposure

Cohort effect estimate Primary outcome

Study conclusion

Grams/day

Post

HR = 1.00 First breast cancer HR = 0.99 (0.87–1.12) recurrence, metastasis or HR = 1.03 (0.86–1.24) new primary breast cancer HR = 1.12 (0.93–1.34)

Grams/day

Post

Non-drinker (<0.36 g/day) Occasional (0.36–<6 g/day) Regular low (6– <12 g/day) Regular medium (12– <24 g/day) Regular high (P24 g/day) Non-drinker (0– <0.36 g/day) 0.36–6 g/day <6–<12 g/day P12 (P1 drink/day)

Regular consumption of more than three drinks per week associated with an approximate 19% increased risk of recurrence in postmenopausal women Alcohol intake of at least one drink per day associated with an approximate 28% increased risk of late recurrence

Second primary breast cancer Bernstein et al. (1992) Participants undertook a [24] structured interview

History of previous alcohol intake

Unde-termined

Li et al. (2003) [25]

Participants interviewed in person and by phone using a verbal questionnaire

Drinks/week

Pre

Trentham-Dietz et al. (2007) [27]

Participants interviewed by phone using a study-specific questionnaire

Drinks/week

Pre

Knight et al. (2009) [28]

Participants interviewed by phone using a study-specific questionnaire

Ever drank regularly

Pre & Post

Breast cancer recurrence (pooled) Kwan et al. (2013) [11] Participants from all cohorts completed validated FFQs

Nechuta et al. (2015) [12]

Participants from all cohorts completed validated FFQs

Ever drank regularly during at-risk period

Drinking years

Drinks/day

Starting age (years of age)

Never drink Ever drink (NS)

HR = 1.04 (0.84–1.31) HR = 1.00 Any second breast cancer event occurring P5 years HR = 1.09 (0.89–1.32) after first breast cancer, HR = 1.06 (0.79–1.42) including local, regional, HR = 1.28 (1.01–1.62) metastases

RR = 1.00 Independent carcinoma RR = 1.11 (0.63–1.97) in situ or invasive lesion diagnosed in the contralateral breast None to <1 drink/week HR = 1.00 Second breast tumour 1–3 drinks/week HR = 0.90 (0.5–1.6) (invasive) diagnosed in the >3 drinks/week HR = 0.90 (0.5–1.5) contralateral breast >6 months after first breast cancer Recent alcohol intake: Second breast tumour None HR = 1.00 diagnosed in the Any HR = 1.09 (0.85–1.41) contralateral breast P12 1–7 drinks/week HR = 1.09 (0.85–1.41) months after first breast >7 drinks/week HR = 1.09 (0.78–1.53) cancer * Ipsilateral breast cancer not considered unless histologic types were different and diagnosed at least twelve months apart Ever drank regularly: Second primary in situ or No RR = 1.0 invasive breast cancer Yes RR = 1.3 (1.0–1.6) diagnosed in the Ever drank regularly during contralateral breast P1 at-risk period: year after first breast cancer No RR = 1.0 Yes RR = 1.2 (0.9–1.5) Lifetime duration of drinking: Never RR = 1.0 <20 drinking years RR = 1.2 (0.9–1.7) 20–<30 drinking years RR = 1.3 (0.9–1.7) P30 drinking years RR = 1.4 (1.0–1.9) Average drinking amount: Never RR = 1.0 <1 drink/day RR = 1.3 (1.0–1.7) P1 drink/day RR = 1.2 (0.8–1.7) Starting age: Never RR = 1.0 P20 years of age RR = 1.4 (1.1–1.8) <20 years of age RR = 1.1 (0.8–1.5)

No association between alcohol and incidence of second primary breast cancer No association between alcohol and incidence of second primary breast cancer No association between alcohol and incidence of second primary breast cancer

Late age (P20 years) of drinking commencement associated with an increased risk of asynchronous contralateral breast cancer

P. Simapivapan et al. / Cancer Treatment Reviews 50 (2016) 155–167

Unit of measurement

(continued on next page) 161

P. Simapivapan et al. / Cancer Treatment Reviews 50 (2016) 155–167

Second primary invasive contralateral breast cancer

Regular consumption of P7 drinks/week associated with an increased risk of contralateral breast cancer when assessed over interval between first breast cancer and reference date

development of second primary breast cancer, death, or study closure. Two studies [16,24] included women diagnosed with any primary breast cancer (TNM stages 0-IV), nine [11,12,15,19–22,26,28] included only women diagnosed with TNM stages I, II, or III breast cancer, one study [17] included in situ disease (TNM stages 0-III), two studies [25,27] included stage IV breast cancer (TNM stages I-IV), one study [18] included stages I and II breast cancer only, and one study [23] investigated only ductal carcinoma in situ (DCIS). One study [26] included participants with TNM stage I, II, or III breast cancer, but only if the initial breast cancer was oestrogen-receptor positive.

OR = 1.0 OR = 1.6 (1.0–2.4) OR = 1.0 (0.5–1.8) OR = 1.9 (1.1–3.2)

Scores for quality assessment are presented in Table 3. Seven of the 16 studies were rated high quality, eight were rated fair quality, and one study was rated poor quality. The items most commonly assigned no stars were: method of assessing alcohol exposure (e.g. lack of validated tools), method of defining cancer status (e.g. self-reported as opposed to medical records), and adequacy of follow-up of cohorts. Assessment of alcohol exposure

Abbreviations: NS = not specified; FFQ = food frequency questionnaire.

Pre & Post Drinks/week Participants interviewed by phone using a study-specific questionnaire Li et al. (2009) [26]

Pre or post diagnosis exposure Alcohol assessment methodology

Unit of measurement

Average alcohol at first breast cancer diagnosis: None <3 drinks/week 3–6.9 drinks/week P7 drinks/week Average alcohol between first diagnosis and reference date: None <3 drinks/week 3–6.9 drinks/week P7 drinks/week

OR = 1.0 OR = 1.6 (1.0–2.5) OR = 1.4 (0.7–2.5) OR = 1.7 (1.0–2.9)

Quality assessment

Study

Table 4 (continued)

Alcohol exposure

Cohort effect estimate Primary outcome

Study conclusion

162

Table 4 presents alcohol assessment methodology and outcome measures (i.e. breast cancer recurrence or second primary breast cancer) used in each study. In a majority of the studies, the method of assessing alcohol intake involved participants either completing food frequency questionnaires (FFQs) or structured interviews, usually as part of a broader dietary history. Interviews were conducted in person or by telephone. Of the 16 included studies, seven used validated FFQs or new FFQs based on pre-existing validated FFQs to assess alcohol intake [11,12,16,19–22], six studies used study-specific questionnaires of unknown validity [15,17,25–28], two studies used structured interviews seeking detailed participant recall of alcoholic beverages consumed within a given time period [23,24], and one study used general information derived from breast cancer risk assessment forms extracted from the participants’ medical records [18]. Named and validated FFQs used include an FFQ by the National Cancer Institute [29]. The Arizona Food Frequency Questionnaire [30], and the Fred Hutchinson Cancer Research Center Food Questionnaire [31]. Validated FFQs mentioned in other studies were unidentifiable. The period during which alcohol exposure was assessed differed between studies. Alcohol intake assessments conducted prior to or at the time of the initial breast cancer diagnosis were considered pre-diagnostic assessments (eight studies) [15–19,22,25,27]. Alcohol intake assessments conducted at least six months after the initial breast cancer diagnosis were considered post-diagnostic assessments (four studies) [11,12,20,21], unless it was explicitly stated that participants were asked to refer to a pre-diagnosis time frame when answering questions about their alcohol intake. Alcohol intake assessments conducted within six months after the initial breast cancer diagnosis, and not reported to pertain to any time period in particular, were considered undetermined (one study) [24]. Three studies assessed alcohol intake both pre and postdiagnosis [23,26,28]. The method of reporting alcohol intake also varied between studies. Ten studies [15–17,20,22,23,25–28] reported alcohol intake in terms of standard or non-standardised drinks, units of alcohol, or servings of alcohol per day or per week. Five studies [11,12,19–21] reported intake in grams of alcohol per day or per month. Two studies [22,28] also reported alcohol intake according to drinking years. A further two studies [18,24] reported alcohol intake according to qualitative categories without specifying quantity consumed. In Kwan et al. [20], where alcohol was measured in

P. Simapivapan et al. / Cancer Treatment Reviews 50 (2016) 155–167

grams per day and number of wine servings per week, a serving of wine was stated to be equivalent to 13.7 grams of alcohol. Holm et al. [22] reported alcohol intake as number of units per day and drinking years, with one unit equivalent to 10 grams of alcohol. The remaining studies (n = 8) that classified alcohol consumption in terms of drinks, units, or servings did not specify how much this equated to in grams of alcohol.

163

post-diagnosis alcohol exposure and development of second primary breast cancer. Knight et al. [28] found that late age of drinking commencement (P20 years old) was associated with an approximate 40% increased risk of developing contralateral breast cancer. Li et al. [26] observed an association between postdiagnosis alcohol intake and second primary breast cancer for exposure levels greater than 7 drinks per week (quantity of alcohol in grams not specified).

Outcome measures Of the 16 studies included in this systematic review, 11 assessed breast cancer recurrence [11,12,15–23] and five assessed second primary breast cancer [24–28]. Definitions for breast cancer recurrence varied between the 11 studies (Table 4). Four studies defined local, regional, contralateral, and metastatic events as breast cancer recurrence [11,18–20]. One study clearly stated that contralateral events were not included in the analysis [17], two studies did not specify inclusion of contralateral events as recurrence [12,16], three studies did not specify inclusion of metastatic events as recurrence [21–23], and one study did not provide a definition for breast cancer recurrence [15]. Differences in definitions of second primary breast cancer were evident in the five studies, particularly in regards to time since first breast cancer diagnosis before a second event was considered a second primary, as well as inclusion of non-invasive breast cancer as a second primary breast cancer. Two studies included contralateral breast events diagnosed at least one year after diagnosis of the first breast cancer [27,28], one study included events occurring after six months [25], and two studies did not specify a postdiagnosis timeframe in their inclusion criteria [24,26], Two studies included both in situ and invasive second breast cancer events in their analysis [24,28], two studies specified including only invasive breast cancer [25,26], and one study did not stipulate staging parameters [27]. Alcohol exposure and breast cancer recurrence Of the 11 included studies, five did not find any significant association between alcohol intake and breast cancer recurrence [16–19,21]. Risk estimates in McLaughlin et al. [23] did not reach statistical significance for any category of alcohol intake relative to abstention, but a significant (p = 0.02) linear trend of increasing risk of any second breast cancer event was observed across categories of increasing post-diagnosis alcohol intake. It should be noted that identification of breast cancer recurrence cases in this study depended on participants self-reporting their diagnoses. Two studies [15,22] found a modest but statistically significant association between pre-diagnosis alcohol intake and breast cancer recurrence, although in Herbert et al. [15] this significant association was restricted to beer, and not seen for wine or liquor. Both publications by Kwan [11,20] showed regular consumption of at least three alcoholic drinks (1 drink = 13.7 g of alcohol) per week or six grams of alcohol per day post-diagnosis to be associated with increased risk of breast cancer recurrence, particularly amongst postmenopausal and overweight/obese women. Nechuta et al. [12] focused specifically on second breast cancer events occurring at least 5 years post initial breast cancer diagnosis, and also observed a small positive association for post-diagnosis alcohol intake of at least one drink per day (12 g of alcohol). Alcohol exposure and second primary breast cancer Three of the five studies did not find any significant association between pre-diagnosis alcohol intake and second primary breast cancer [24,25,27]. However, the two case-control studies [26,28] observed modest positive associations between both pre and

Differences in outcomes between studies utilising pre and postdiagnostic alcohol intake assessment methods Studies assessing post-diagnosis alcohol intake showed more consistent associations between alcohol exposure and breast cancer recurrence or second primary breast cancer than studies assessing only pre-diagnosis alcohol intake. Of the seven studies that assessed alcohol exposure after the initial breast cancer diagnosis, a total of five studies (71%) observed some degree of significant positive association between alcohol intake and breast cancer recurrence or second primary breast cancer [11,12,20,23,26,28]. In contrast, only two of the eight studies (25%) assessing only prediagnosis alcohol intake found statistically significant associations between alcohol exposure and primary outcomes [15,22]. In one study [23], neither pre nor post-diagnosis alcohol intake of any category showed a statistically significant association with breast cancer recurrence. However, a significant linear trend of increasing risk was observed over categories of increasing postdiagnosis alcohol intake (p = 0.02). Another study [26] observed a significant increase in risk of second primary breast cancer for post-diagnosis (OR = 1.9 (1.1–3.2)), but not pre-diagnosis, alcohol exposure of at least seven drinks per week. Alcohol in relation to menopause, BMI and hormone receptor status Analyses pertaining to subgroups of breast cancer patients were conducted in five of the included studies [11,15,16,20,23]. Major subgroups included distinction between pre and postmenopausal status; low and high BMI (with varying cut-offs); and oestrogenreceptor status of the initial breast cancer. Refer to Fig. 2 for a forest plot of the risk estimates for these subgroups. Four studies conducted subgroup analyses according to participants’ menopausal status [11,15,16,20]. Herbert et al. [15] observed an association (RR = 1.58 (1.15–2.17)) between breast cancer recurrence and beer consumption, but not with wine or liquor, in premenopausal women. Results of analyses for postmenopausal women were not stated in the published paper. In contrast, both studies published by Kwan et al. [11,20] found positive associations (HR = 1.51 (1.05–2.19), HR = 1.19 (1.01–1.40) respectively) between alcohol intake (of any type) of at least six grams per day and breast cancer recurrence in postmenopausal, but not premenopausal, women. However, only one of these studies showed a significant interaction between alcohol and menopausal status [11]. Saxe et al. [16] did not find any association in either menopausal status subgroup. Three studies conducted subgroup analyses according to participants’ BMI [11,16,20]. In Kwan et al. [20], a significant positive association (HR = 1.60 (1.08–2.38)) was observed between alcohol consumption of at least six grams per day and breast cancer recurrence in overweight participants, but not in participants of normal weight. However, the interaction between alcohol and BMI was not significant. Saxe et al. [16] and Kwan et al. [11] did not find an association between alcohol consumption of any amount and breast cancer recurrence, regardless of the participants’ BMI. Two studies conducted subgroup analyses according to the oestrogen-receptor status of the participants’ initial breast cancer [11,20] Neither of the studies observed any association between

164

P. Simapivapan et al. / Cancer Treatment Reviews 50 (2016) 155–167

alcohol consumption and breast cancer recurrence, regardless of the participants’ first breast cancer oestrogen-receptor status. Discussion The evidence identified in this review is suggestive of a modest positive association between alcohol and breast cancer recurrence. Several studies included in the review performed subgroup analyses according to participants’ menopausal status, BMI and hormone receptor status of the original breast tumour, and found some evidence that increased risk of breast cancer recurrence associated with alcohol consumption may be stronger in postmenopausal and overweight women. In contrast, the evidence for an association between alcohol intake and second primary breast cancer in all groups is less convincing due to the limited number of studies and the high variance in results from these studies. Post-diagnosis alcohol intake was more consistently associated with development of a subsequent breast cancer (recurrence or second primary) than pre-diagnosis alcohol intake. There was a high degree of disparity in exposure measures, outcome definitions, sample characteristics and availability of methodological and exposure effect information in the papers reviewed. Studies examined alcohol exposure using a variety of validated and non-validated tools, of varying units of measurement, and across time frames both before and after diagnosis of the participants’ initial breast cancer. Most of the studies had long follow-up periods averaging 7–10 years, although a few studies followed participants for as little as 5 years [17,18]. This may have limited the number of second breast cancer cases identified, as research has shown that risk of breast cancer recurrence continues to increase long after the 5-year mark and as far as 15 years after treatment [32,33]. Defining breast cancer recurrence On reviewing the articles from a preliminary search of the literature, it was found that a significant number of studies defined

breast cancer recurrence as inclusive of contralateral breast cancer or breast cancers not specified to have originated from the cell line of the original breast tumour. As such, the search phrase was expanded to include ‘second primary’ in order to screen for the maximum number of articles potentially relevant to the research question. The associations of alcohol with breast cancer in studies self-identified to assess breast cancer recurrence were analysed separately to studies self-identified to assess second primary breast cancer. However, due to the aforementioned overlap in outcome definitions between the two study groups, conclusions made regarding the relationship between alcohol consumption and breast cancer recurrence cannot be considered with confidence to be exclusive to true recurrence and not second primary breast cancer.

Timing of alcohol intake assessment Factors such as timing of alcohol intake assessments may lead to an inaccurate representation of participants’ true alcohol intake, therefore influencing study findings. Extrapolating participants’ level of alcohol consumption prior to cancer diagnosis may potentially lead to an overestimation of post-diagnosis alcohol intake. Research into the psychology of cancer survivors has shown that life-threatening events, such as a diagnosis of breast cancer, can be a powerful motivator for patients to make healthier lifestyle choices [34,35]. This is supported by several studies that have observed a decrease in reported alcohol consumption among 8–39% of breast cancer survivors after diagnosis [36–39]. Conversely, alcohol intake assessments occurring after diagnosis but during cancer treatment run the risk of underestimating participants’ alcohol intake due to the documented effects of these treatments on dietary habits such as food or drink preferences and appetite, including aversions to alcoholic beverages [40–42]. A post-diagnosis, post-treatment assessment of alcohol consumption is therefore thought to be most relevant to risk of cancer recurrence or secondary cancer.

Fig. 2. Forest plot representing highest consumption group risk estimates from subgroup analyses.

P. Simapivapan et al. / Cancer Treatment Reviews 50 (2016) 155–167

In the vast majority of studies, timing of alcohol intake assessment as pertaining to pre or post-diagnosis was clearly reported. However, Bernstein et al. [24] assessed alcohol intake within six months of the participants’ initial breast cancer diagnosis, but did not state whether participants reported on current alcohol intake or if they were asked to reflect on intake prior to their first cancer diagnosis. As a result, the time frame for which alcohol was assessed was classified as undetermined for this systematic review. Validity of alcohol exposure assessment methods Studies used a variety of tools to assess quantities of alcohol consumption. Of the tools used, validated food frequency questionnaires (FFQs) were considered most reliable, and studies that did not utilise this method were classified as lower quality in regard to their data collection procedures. Although validated measurement tools imply a degree of reliability, it should be noted that the value of FFQs in providing an accurate assessment of dietary intake has previously been questioned [43–46]. The use of multiple-day food records or multiple 24-h recalls have been suggested as viable and superior alternatives, but the issue of cost might prevent uptake of these methods [43]. Where standard drinks were used as the unit of measure, there was no sense of the extent to which participants understood the amount of alcohol that was meant by this. This can be addressed through increased support for participants to accurately recount total volumes of alcohol consumption through use of visual prompts and examples of portion sizes when assessing alcohol intake, or, where the method is sound, increased transparency in reporting. It is known that misreporting (both intentional and unintentional) is a major limitation of self-reported methods for assessing dietary intake [47,48]. Measures should be taken to reduce this potential for bias by, for example, limiting the historical time frame that participants are asked to refer to in their reporting to increase accuracy of recall, although this may be at the expense of longer term representativeness [49]. Researchers should also consider the potential for social desirability bias, whereby participants intentionally underestimate their level of alcohol consumption to portray what is perceived to be more socially acceptable behaviour [50]. Minimisation of this bias can be encouraged through assurance of confidentiality and anonymity [51], and by asking participants to report their alcohol intake according to more detailed response options (i.e. beverage type, strength, container sizes) rather than standard drinks [52]. Classification of alcohol exposure groups Population level recommendations for upper limits of alcohol consumption exist in many nations as part of public health strategies aimed at reducing long-term adverse health effects. These recommendations vary from country to country. The United States Department of Agriculture recommends women consume not more than 1 standard drink per day (where 1 drink = 14 g of alcohol; therefore a maximum of 98 g of alcohol per week) [53]. The UK Department of Health recommends individuals consume not more than 14 units per week (where 1 unit = 8 g of alcohol; maximum total upper limit of 112 g of alcohol per week) [54]. In Australia, the National Health and Medical Research Council (NHMRC) recommends individuals consume not more than 2 standard drinks per day in order to reduce their lifetime risk of harm from alcohol-related disease or injury (where 1 drink = 10 g of alcohol; maximum total upper limit of 140 g of alcohol per week) [55]. Public health recommendations specific for the prevention of primary breast cancer and recurrence generally state that individuals should either abstain from drinking, or limit their alcohol consumption to levels specified in the general guidelines [5,56].

165

Cohort studies assessing alcohol intake have the potential to reflect the degree of alignment of dietary behaviours with public health guidelines in women with breast cancer. However, in studies reviewed here, variations in how alcohol intake was quantified and reported challenge attempts to interpret the extent to which safe limits of alcohol consumption are adhered to. For example, two studies [20,25] included in this review made no further distinctions in categories of alcohol intake other than <6 g of alcohol consumed per day and P6 g of alcohol consumed per day, thus providing no information on higher levels of alcohol intake. Studies [11,22] that report alcohol intake in categories of <1, 1 to 2 and >2 standard drinks are more comparable with national guidelines in that they allow for interpretation of compliance with, and consequences of adherence or non-adherence to, the Australian, UK and United States recommendations for upper limits of alcohol intake, although it is unclear in these studies whether a ‘standard drink’ was defined in the same way as it is defined in local public health recommendations. Therefore, we recommend that future studies should include alcohol intake categories that incorporate the local alcohol recommendations specific to the population of interest. Alcohol exposure in post-menopausal and overweight women This review found a small body of evidence supporting a modest increase in risk of breast cancer recurrence associated with alcohol consumption specifically in post-menopausal women and, to a lesser extent, overweight women. However, only one study [11] showed a significant interaction between alcohol and menopausal status, and no significant interactions between alcohol and BMI were found. Despite these findings, lack of significant interaction does not necessarily mean this association does not exist. If an association between alcohol exposure and breast cancer recurrence only exists in postmenopausal or overweight participants, this may have contributed to differences in observations between studies with different proportions of these subgroups. For example, studies in which analyses were performed on a mixed sample comprised of more premenopausal than postmenopausal women might find lower associations between alcohol and breast cancer recurrence. Furthermore, there is good evidence supporting an association between obesity and breast cancer in postmenopausal women [57–60]. Menopause is linked to dietindependent of increases in adiposity and insulin resistance [61]. Obese women possess elevated activity of the aromatase enzyme, which is responsible for oestrogen synthesis, in breast tissue [62]. It is hypothesised that this increase in levels of circulating oestrogen is responsible for stimulating breast cancer growth [57,63]. Similarly, alcohol intake has been linked to increased levels of androgens in postmenopausal women, which are in turn metabolised to oestrogen in breast tissue [64,65]. This common link between obesity, menopause, alcohol and elevated circulating oestrogen may imply an additive relationship between these factors to increase the risk of breast cancer recurrence, leading to a pressing need for research studies specifically designed and appropriately powered to test for interactions with menopausal status and BMI. Limitations There are several limitations within this systematic review. First, study selection involved filtering for English language articles, potentially resulting in the exclusion of relevant, non English publications. Second, many of the studies included in this review did not focus primarily on alcohol and breast cancer recurrence or second primary breast cancer, but instead on the relationship between other dietary components and disease progression. In

166

P. Simapivapan et al. / Cancer Treatment Reviews 50 (2016) 155–167

these cases, alcohol intake was sometimes a minor component of analysis, and information relating to the methodology of alcohol exposure assessment was limited. Third, in some studies analyses were either performed without adjusting for any confounding factors [18], or analyses did not account for the factors considered most important in regard to the outcome of interest, such as age, BMI and stage of the initial breast cancer [16,28]. Fourth, a metaanalysis was not possible due to the high level of clinical and methodological heterogeneity present between studies, particularly in the aspects of alcohol exposure groups and outcome definitions. This precluded the pooling of effect estimates, as any attempt to render the data to a comparable baseline would require a degree of assumption that would negate the potential power of any statistical analyses performed [66]. Conclusion Research into the relationship between alcohol consumption and breast cancer recurrence or second primary breast cancer suffers from variations and inconsistencies in study methodology and outcome definitions, making it difficult to draw conclusions. Despite these difficulties, this systematic review found some evidence that alcohol consumption, potentially from levels as low as 6 g of alcohol per day, modestly increases the risk of breast cancer recurrence (particularly in postmenopausal women). The evidence for an association between alcohol and second primary breast cancer is less clear. There is a need for future longitudinal studies assessing post-diagnosis alcohol consumption in relation to breast cancer recurrence and second primary breast cancer using standardised and uniform methodology, with particular emphasis on sufficient sample size for subgroup analyses of overweight/obese and postmenopausal women. Such data has the potential to support the development of public health recommendations specific for breast cancer survivors, thereby providing clearer guidance for clinicians in the provision of evidence-based alcohol advice to breast cancer patients. Conflicts of interest None. Funding This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. Appendix A. Supplementary data Supplementary data associated with this article can be found, in the online version, at http://dx.doi.org/10.1016/j.ctrv.2016.09.010. References [1] Ferlay J, Soerjomataram I, Ervik M, Dikshit R, Eser S, Mathers C, et al. GLOBOCAN 2012 v1.1, Cancer Incidence and Mortality Worldwide: IARC CancerBase No. 11 [Internet]. ; 2014 [accessed 05.03.16]. [2] Scoccianti C, Lauby-Secretan B, Bello P-Y, Chajes V, Romieu I. Female breast cancer and alcohol consumption: a review of the literature. Am J Prev Med 2014;46:S16–25. [3] Mørch LS, Johansen D, Thygesen LC, Tjønneland A, Løkkegaard E, Stahlberg C, et al. Alcohol drinking, consumption patterns and breast cancer among Danish nurses: a cohort study. Eur J Public Health 2007;17:624–9. [4] Allen NE, Beral V, Casabonne D, Kan SW, Reeves GK, Brown A, et al. Moderate alcohol intake and cancer incidence in women. J Natl Cancer Inst 2009;101:296–305. [5] Wiseman M, The Second World Cancer Research Fund/American Institute for Cancer Research Expert Report. Food, nutrition, physical activity, and the prevention of cancer: a global perspective. Proc Nutr Soc 2008;67:253–6.

[6] Correa C, McGale P, Taylor C, Wang Y, Clarke M, Davies C, et al. Overview of the randomized trials of radiotherapy in ductal carcinoma in situ of the breast. J Natl Cancer Inst Monogr 2010;162–77. [7] Bijker N, Meijnen P, Peterse JL, Bogaerts J, Van Hoorebeeck I, Julien JP, et al. Breast-conserving treatment with or without radiotherapy in ductal carcinoma-in-situ: ten-year results of European Organisation for Research and Treatment of Cancer randomized phase III trial 10853 – a study by the EORTC Breast Cancer Cooperative Group and EORTC Radiotherapy Group. J Clin Oncol 2006;24:3381–7. [8] Lagerdahl AS, Moynihan M, Stollery B. An exploration of the existential experiences of patients following curative treatment for cancer: reflections from a U.K. Sample. J Psychosocial Oncol 2014;32:555–75. [9] Williams K, Beeken RJ, Wardle J. Health behaviour advice to cancer patients: the perspective of social network members. Br J Cancer 2013;108:831–5. [10] Moher D, Liberati A, Tetzlaff J, Altman DG. Preferred reporting items for systematic reviews and meta-analyses: the PRISMA statement. BMJ 2009;339. [11] Kwan ML, Chen WY, Flatt SW, Weltzien EK, Nechuta SJ, Poole EM, et al. Postdiagnosis alcohol consumption and breast cancer prognosis in the after breast cancer pooling project. Cancer Epidemiol Biomarkers Prev 2013;22:32–41. [12] Nechuta S, Chen WY, Cai H, Poole EM, Kwan ML, Flatt SW, et al. A pooled analysis of post-diagnosis lifestyle factors in association with late estrogenreceptor positive breast cancer prognosis. Int J Cancer 2015;138:2088–97. [13] Wells G, Shea B, O’Connell D, Peterson J, Welch V, Losos M, et al. The Newcastle-Ottawa Scale (NOS) for assessing the quality of nonrandomised studies in meta-analyses. http://www.ohri.ca/programs/ clinical_epidemiology/oxford.asp; 2013 [accessed 24.02.16]. [14] Higgins J, Green S. Cochrane handbook for systematic reviews of interventions Version 5.1.0 [updated March 2011]. http://www.cochrane-handbook.org.; 2011 [accessed 25.02.16]. [15] Hebert JR, Hurley TG, Ma YS. The effect of dietary exposures on recurrence and mortality in early stage breast cancer. Breast Cancer Res Treat 1998;51:17–28. [16] Saxe GA, Rock CL, Wicha MS, Schottenfeld D. Diet and risk for breast cancer recurrence and survival. Breast Cancer Res Treat 1999;53:241–53. [17] Muscat JE, Britton JA, Djordjevic MV, Citron ML, Kemeny M, Busch-Devereaux E, et al. Adipose concentrations of organochlorine compounds and breast cancer recurrence in Long Island, New York. Cancer Epidemiol Biomarkers Prev 2003;12:1474–8. [18] Brewster AM, Do KA, Thompson PA, Hahn KM, Sahin AA, Cao Y, et al. Relationship between epidemiologic risk factors and breast cancer recurrence. J Clin Oncol 2007;25:4438–44. [19] Vrieling A, Buck K, Heinz J, Obi N, Benner A, Flesch-Janys D, et al. Prediagnostic alcohol consumption and postmenopausal breast cancer survival: a prospective patient cohort study. Breast Cancer Res Treat 2012;136:195–207. [20] Kwan ML, Kushi LH, Weltzien E, Tam EK, Castillo A, Sweeney C, et al. Alcohol consumption and breast cancer recurrence and survival among women with early-stage breast cancer: the life after cancer epidemiology study. J Clin Oncol 2010;28:4410–6. [21] Flatt SW, Thomson CA, Gold EB, Natarajan L, Rock CL, Al-Delaimy WK, et al. Low to moderate alcohol intake is not associated with increased mortality after breast cancer. Cancer Epidemiol Biomarkers Prev 2010;19:681–8. [22] Holm M, Olsen A, Christensen J, Kroman NT, Bidstrup PE, Johansen C, et al. Prediagnostic alcohol consumption and breast cancer recurrence and mortality: results from a prospective cohort with a wide range of variation in alcohol intake. Int J Cancer 2013;132:686–94. [23] McLaughlin VH, Trentham-Dietz A, Hampton JM, Newcomb PA, Sprague BL. Lifestyle factors and the risk of a second breast cancer after ductal carcinoma in situ. Cancer Epidemiol Biomarkers Prev 2014;23:450–60. [24] Bernstein JL, Thompson WD, Risch N, Holford TR. Risk factors predicting the incidence of second primary breast cancer among women diagnosed with a first primary breast cancer. Am J Epidemiol 1992;136:925–36. [25] Li CI, Malone KE, Porter PL, Daling JR. Epidemiologic and molecular risk factors for contralateral breast cancer among young women. Br J Cancer 2003;89:513–8. [26] Li CI, Daling JR, Porter PL, Tang MTC, Malone KE. Relationship between potentially modifiable lifestyle factors and risk of second primary contralateral breast cancer among women diagnosed with estrogen receptor-positive invasive breast cancer. J Clin Oncol 2009;27:5312–8. [27] Trentham-Dietz A, Newcomb PA, Nichols HB, Hampton JM. Breast cancer risk factors and second primary malignancies among women with breast cancer. Breast Cancer Res Treat 2007;105:195–207. [28] Knight JA, Bernstein L, Largent J, Capanu M, Begg CB, Mellemkjaer L, et al. Alcohol intake and cigarette smoking and risk of a contralateral breast cancer. Am J Epidemiol 2009;169:962–8. [29] Subar AF, Thompson FE, Kipnis V, Midthune D, Hurwitz P, McNutt S, et al. Comparative validation of the Block, Willett, and National Cancer Institute food frequency questionnaires: the Eating at America’s Table Study. Am J Epidemiol 2001;154:1089–99. [30] Martinez ME, Marshall JR, Graver E, Whitacre RC, Woolf K, Ritenbaugh C, et al. Reliability and validity of a self-administered food frequency questionnaire in a chemoprevention trial of adenoma recurrence. Cancer Epidemiol Biomarkers Prev 1999;8:941–6. [31] Kristal AR, Feng Z, Coates RJ, Oberman A, George V. Associations of race/ ethnicity, education, and dietary intervention with the validity and reliability of a food frequency questionnaire: the women’s health trial feasibility study in minority populations. Am J Epidemiol 1997;146:856–69.

P. Simapivapan et al. / Cancer Treatment Reviews 50 (2016) 155–167 [32] Davies C, Godwin J, Gray R, Clarke M, Cutter D, Darby S, et al. Relevance of breast cancer hormone receptors and other factors to the efficacy of adjuvant tamoxifen: patient-level meta-analysis of randomised trials. Lancet 2011;378:771–84. [33] Jatoi I, Anderson WF, Jeong JH, Redmond CK. Breast cancer adjuvant therapy: time to consider its time-dependent effects. J Clin Oncol 2011;29:2301–4. [34] Bluethmann SM, Basen-Engquist K, Vernon SW, Cox M, Gabriel KP, Stansberry SA, et al. Grasping the ‘teachable moment’: time since diagnosis, symptom burden and health behaviors in breast, colorectal and prostate cancer survivors. Psychooncology 2015;24:1250–7. [35] McBride CM, Clipp E, Peterson BL, Lipkus IM, Demark-Wahnefried W. Psychological impact of diagnosis and risk reduction among cancer survivors. Psychooncology 2000;9:418–27. [36] Maskarinec G, Murphy S, Shumay DM, Kakai H. Dietary changes among cancer survivors. Eur J Cancer Care (Engl) 2001;10:12–20. [37] Salminen E, Bishop M, Poussa T, Drummond R, Salminen S. Dietary attitudes and changes as well as use of supplements and complementary therapies by Australian and Finnish women following the diagnosis of breast cancer. Eur J Clin Nutr 2004;58:137–44. [38] Vance V, Campbell S, McCargar L, Mourtzakis M, Hanning R. Dietary changes and food intake in the first year after breast cancer treatment. Appl Physiol Nutr Metab 2013;39:707–14. [39] Velentzis LS, Keshtgar MR, Woodside JV, Leathem AJ, Titcomb A, Perkins KA, et al. Significant changes in dietary intake and supplement use after breast cancer diagnosis in a UK multicentre study. Breast Cancer Res Treat 2011;128:473–82. [40] Bernhardson B-M, Tishelman C, Rutqvist LE. Self-reported taste and smell changes during cancer chemotherapy. Support Care Cancer 2007;16:275–83. [41] Holmes S. Food avoidance in patients undergoing cancer chemotherapy. Support Care Cancer 1993;1:326–30. [42] Boltong A, Aranda S, Keast R, Wynne R, Francis PA, Chirgwin J, et al. A prospective cohort study of the effects of adjuvant breast cancer chemotherapy on taste function, food liking, appetite and associated nutritional outcomes. PLoS ONE 2014;9:e103512. [43] Kristal AR, Peters U, Potter JD. Is it time to abandon the food frequency questionnaire? Cancer Epidemiol Biomarkers Prev 2005;14:2826–8. [44] Willett WC, Hu FB. The food frequency questionnaire. Cancer Epidemiol Biomarkers Prev 2007;16:182–3. [45] Kelemen LE. Food frequency questionnaires: not irrelevant yet. Cancer Epidemiol Biomarkers Prev 2006;15:1054. [46] Kristal AR, Potter JD. Not the time to abandon the food frequency questionnaire: counterpoint. Cancer Epidemiol Biomarkers Prev 2006;15:1759–60. [47] Poslusna K, Ruprich J, de Vries JH, Jakubikova M, van’t Veer P. Misreporting of energy and micronutrient intake estimated by food records and 24 hour recalls, control and adjustment methods in practice. Br J Nutr 2009;101(Suppl 2):S73–85. [48] Johnson RK. Dietary intake–how do we measure what people are really eating? Obes Res 2002;10(Suppl 1):63s–8s.

167

[49] Smith AF, Jobe JB, Mingay DJ. Retrieval from memory of dietary information. Appl Cogn Psychol 1991;5:269–96. [50] Davis CG, Thake J, Vilhena N. Social desirability biases in self-reported alcohol consumption and harms. Addict Behav 2010;35:302–11. [51] Tourangeau R, Yan T. Sensitive questions in surveys. Psychol Bull 2007;133:859–83. [52] Stockwell T, Donath S, Cooper-Stanbury M, Chikritzhs T, Catalano P, Mateo C. Under-reporting of alcohol consumption in household surveys: a comparison of quantity-frequency, graduated-frequency and recent recall. Addiction 2004;99:1024–33. [53] U.S. Department of Health and Human Services and U.S. Department of Agriculture. 2015–2020 Dietary Guidelines for Americans. http://health.gov/ dietaryguidelines/2015/guidelines/; 2015 [accessed 10.04.16]. [54] Lea W. UK Chief Medical Officers’ Alcohol Guidelines Review. https://www. gov.uk/government/consultations/health-risks-from-alcohol-new-guidelines; 2015 [accessed 10.04.16]. [55] Australian Government (National Health and Medical Research Council). Alcohol guidelines: reducing the health risks. https://www.nhmrc.gov.au/ health-topics/alcohol-guidelines; 2015 [accessed 10.04.16]. [56] Kushi LH, Doyle C, McCullough M, Rock CL, Demark-Wahnefried W, Bandera EV, et al. American Cancer Society Guidelines on nutrition and physical activity for cancer prevention: reducing the risk of cancer with healthy food choices and physical activity. CA Cancer J Clin 2012;62:30–67. [57] Calle EE, Kaaks R. Overweight, obesity and cancer: epidemiological evidence and proposed mechanisms. Nat Rev Cancer 2004;4:579–91. [58] Galanis DJ, Kolonel LN, Lee J, Le Marchand L. Anthropometric predictors of breast cancer incidence and survival in a multi-ethnic cohort of female residents of Hawaii, United States. Cancer Causes Control 1998;9:217–24. [59] Trentham-Dietz A, Newcomb PA, Storer BE, Longnecker MP, Baron J, Greenberg ER, et al. Body size and risk of breast cancer. Am J Epidemiol 1997;145:1011–9. [60] Hunter DJ, Willett WC. Diet, body size, and breast cancer. Epidemiol Rev 1993;15:110–32. [61] Rogers NH, Perfield 2nd JW, Strissel KJ, Obin MS, Greenberg AS. Reduced energy expenditure and increased inflammation are early events in the development of ovariectomy-induced obesity. Endocrinology 2009;150:2161–8. [62] Morris PG, Hudis CA, Giri D, Morrow M, Falcone DJ, Zhou XK, et al. Inflammation and increased aromatase expression occur in the breast tissue of obese women with breast cancer. Cancer Prev Res (Phila) 2011;4:1021–9. [63] Rose DP, Gracheck PJ, Vona-Davis L. The interactions of obesity, inflammation and insulin resistance in breast cancer. Cancers 2015;7:2147–68. [64] Liu Y, Nguyen N, Colditz GA. Links between alcohol consumption and breast cancer: a look at the evidence. Women’s Health (London, England). 2015;11:65–77. [65] Key TJ, Appleby PN, Reeves GK, Roddam AW, Helzlsouer KJ, Alberg AJ, et al. Circulating sex hormones and breast cancer risk factors in postmenopausal women: reanalysis of 13 studies. Br J Cancer 2011;105:709–22. [66] Melsen WG, Bootsma MCJ, Rovers MM, Bonten MJM. The effects of clinical and statistical heterogeneity on the predictive values of results from metaanalyses. Clin Microbiol Infect 2014;20:123–9.