- Email: [email protected]
Re: Shift Work and Prostate Cancer Incidence in Industrial Workers: A Historical Cohort Study in a German Chemical Company
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EUROPEAN UROLOGY 69 (2016) 174–178
Re: Long-term Results of Thulium Laser Resection of the Prostate: A Prospective Study at Multiple Centers Sun F, Han B, Cui D, et al World J Urol 2015;33:503–8 Experts’ summary: In a retrospective, long-term, multisite study, Sun and colleagues demonstrated the safety, efficiency, and durability of thulium laser resection of prostate (TmLRP) in the treatment of benign prostatic hyperplasia (BPH). Of 2216 patients recruited at four medical centers, 541 (24.4%) were available for the longest follow-up period (8 yr). Compared with baseline, there were significant improvements in International Prostate Symptom Score, maximum urinary flow rate, quality of life, and postvoid residual urine by 3 mo after surgery and throughout the 8-yr follow-up period. Long-term complications were noted in 122 patients (5.5%): 58 (2.6%) had urethral stricture, 35 (1.6%) had bladder neck contracture, 2 (0.1%) had persistent stress incontinence, and 27 (1.2%) had BPH recurrence. Experts’ comments: The safety and efficacy of TmLRP as a minimally invasive procedure for the surgical treatment of BPH has been demonstrated by many clinical trials [1]. Compared with transurethral resection of the prostate (TURP), TmLRP has been shown to be superior with respect to hemostasis [2]. As emphasized by the authors, however, the evidence regarding the long-term safety and efficacy of TmLRP is limited. Consequently, we congratulate the authors for conducting this study, which aimed to evaluate the long-term durability of TmLRP. Nevertheless, we would like to point out a few issues. First, although it has been shown that short-term resolution of symptoms is not associated with the percentage of prostate volume removed [3], many urologists still believe that, in the long-term, the resolution of symptoms is associated with the extent of resection [4]. Based on our experience with TURP and TmLRP, the loop electrode used for TURP easily removes more tissue and makes the surgical margin more regular compared with the laser fibers used for TmLRP, especially during resection of the part of the media lobes below the verumontanum level. This is due to the different shape of the instrument
Re: Shift Work and Prostate Cancer Incidence in Industrial Workers: A Historical Cohort Study in a German Chemical Company Hammer GP, Emrich K, Nasterlack M, Blettner M, Yong M Dtsch Arztebl Int 2015;112:463–70 Experts’ summary: In a their recent original article, Hammer and coworkers showed that shift workers do not develop prostate cancer (PCa) more frequently than their colleagues who work during the day. The aim of this case–control study was to investigate the incidence of PCa in a cohort of shift workers versus
used in TmLRP and TURP. We speculate that less tissue will be removed with TmLRP, and thus the long-term results of TmLRP would be worse than TURP. Future studies should directly evaluate the long-term outcomes of TURP versus TmLRP, and the residual prostatic weight and prostate-specific antigen levels should be included in the assessments. Second, this study is significantly limited by the fact that a large number of patients were lost to follow-up (75.6% at 8 yr); however, if the main reasons for the number of patients lost to follow-up were listed in the article, then it would be helpful in interpreting the results and drawing more convincing conclusions about the durability of TmLRP. In summary, we agree with the authors that TmLRP is a safe and effective procedure, but the long-term durability of TmLRP requires additional research. Conflicts of interest: The authors have nothing to disclose.
References [1] Zhu Y, Zhuo J, Xu D, et al. Thulium laser versus standard transurethral resection of the prostate for benign prostatic obstruction: a systematic review and meta-analysis. World J Urol 2015;33:509–15. [2] Xia SJ, Zhuo J, Sun XW, et al. Thulium laser versus standard transurethral resection of the prostate: a randomized prospective trial. Eur Urol 2008;53:382–9. [3] Hakenberg OW, Helke C, Manseck A, Wirth MP. Is there a relationship between the amount of tissue removed at transurethral resection of the prostate and clinical improvement in benign prostatic hyperplasia. Eur Urol 2001;39:412–7. [4] Bachmann A, Rieken M. Words of wisdom. Re: GreenLight laser (XPS) photoselective vapo-enucleation versus holmium laser enucleation of the prostate for the treatment of symptomatic benign prostate hyperplasia: a randomized controlled study. Eur Urol 2015;67:976. Hao Yan, Jing Li, Xin Cui, Tong-wen Ou* Department of Urology, Xuanwu Hospital, Capital Medical University, Beijing, People’s Republic of China *Corresponding author. Department of Urology, Xuanwu Hospital, Capital Medical University, 45 Changchun Street, Beijing, People’s Republic of China. E-mail address: [email protected] (T. Ou). http://dx.doi.org/10.1016/j.eururo.2015.10.033
day workers. The authors evaluated the personnel and health data of almost 28 000 employees of a chemical company in Rhineland-Palatinate, Germany, between 1995 and 2005. They found 146 new cases of PCa in 12 609 rotating shift workers and 191 cases in 15 219 daytime workers. The year of birth was similar between the two groups: 1960 in the first group and 1959 in the second. The shift workers did not have an elevated hazard ratio (HR) for PCa in comparison to the daytime workers (HR: 0.93 [95% confidence interval (CI), 0.73–1.18]). There was a nonsignificant increase in the risk of a diagnosis of stage T1 or T4 PCa (HR: 1.26 [95% CI, 0.44–3.86] vs 1.36 [95% CI, 0.25–6.18]) and a decreased risk for stages T2 and
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EUROPEAN UROLOGY 69 (2016) 174–178
T3 (HR 0.84 [95% CI, 0.62–1.15] vs 0.90 [95% CI, 0.53–1.52]). The authors’ conclusion contradicted the findings of previous smaller studies, with fewer participants, on the same subject that had reported an increased risk of PCa for shift workers [1,2]. Experts’ comments: We would like to praise the authors who analysed the effect of shift work on PCa in a large number of participants with well-documented data and adequate methods. Although the International Agency for Research on Cancer classified shift work as a carcinogen, most of the evidence comes from basic science or animal experiments, and only a few reliable epidemiologic studies exist, namely, breast cancer in female nurses and flight attendants [3]. It is thought that desynchronisation of circadian rhythms (ie, by nocturnal light exposure) suppresses melatonin secretion, leading to the loss of prevention and inhibition of cancer growth factor secretion. Epidemiologic data have shown that shift workers are at an increased risk of cardiovascular disease and breast cancer [3]. PCa is a genetic and clinically heterogeneous disease, and although many gaps are now closed, many others are not. Family history, race/ethnicity, geography, diet, obesity, smoking, and chronic inflammation are well-recognised risk factors for PCa, but shift work is not, according to Hammer and colleagues. As urologists, we should not underestimate the issue behind this paper. The production and release of nearly all hormones exhibit diurnal timing patterned on an approximately 24-hour cycle. Life style and working factors, such as night shift work and sleep desyncronisation with a consequent exposure to light at night, that disrupt circadian rhythm may also alter endocrine function and possibly the regulation of sexual hormones that are also relevant to the aetiology of hormone-dependent PCa and erectile dysfunction. Salonia et al reported that sex steroids are independent
predictors of high-risk PCa, depicting a nonlinear U-shape [4]. On July 31, 2015, The Economist reported that although the latest euro-area figures show that the overall unemployment rate has crept down to 11.1% from its peak of 12.1% in April 2013, unemployment remains high, especially in south Europe. The situation could push male workers, coping with unemployment, to accept more and more shift jobs under poorly controlled rules. Despite the conclusions of Hammer et al, this might affect the epidemiology of urologic diseases. Conflict of interest: The authors have nothing to disclose.
References [1] Kubo T, Oyama I, Nakamura T, et al. Industry-based retrospective cohort study of the risk of prostate cancer among rotating-shift workers. Int J Urol 2011;18:206–11. [2] Conlon M, Lightfoot N, Kreiger N. Rotating shift work and risk of prostate cancer. Epidemiol 2007;18:182–3. [3] Golubnitschaja O, Yeghiazaryan K, Costigliola V, et al. Risk assessment, disease prevention and personalised treatments in breast cancer: is clinically qualified integrative approach in the horizon? EPMA J 2013;4:6. [4] Salonia A, Abdollah F, Capitanio U, et al. Serum sex steroids depict a nonlinear u-shaped association with high-risk prostate cancer at radical prostatectomy. Clin Cancer Res 2012;18:3648–57. Massimo Lazzeri*, Giorgio Guazzoni Department of Urology, Humanitas Clinical and Research Center, Humanitas University, Rozzano (Milan), Italy *Corresponding author. Department of Urology, Humanitas Clinical and Research Center, Humanitas University, via Manzoni 56, 20089 Rozzano (Milan), Italy. E-mail address: [email protected] (M. Lazzeri). http://dx.doi.org/10.1016/j.eururo.2015.10.034
Re: Residual Parenchymal Volume, Not Warm Ischemia Time, Predicts Ultimate Renal Functional Outcomes in Patients Undergoing Partial Nephrectomy Ginzburg S, Uzzo R, Walton J, et al
follow-up, both preoperative eGFR and %FPV preservation—but not WIT—had significant association with %eGFR preservation.
Urology 2015;86:300–6
Experts’ comments: A body of literature is emerging that identifies the degree of parenchymal preservation and the preoperative quality of the renal parenchyma as key factors affecting post-PN partial renal function [1,2]. This paper goes in that direction, but its message is very strong, thus the reader should bring some points into focus. First, even if the method used to estimate FPV preservation has been used previously [3], it offers an empirical assessment (tumour is not a sphere, and kidney is not a cylinder), and the precision of the estimation is strongly correlated to the lesion location. Second, with the proposed formula, we should assume that the endophytic percentage of the lesion subtracted from the whole parenchymal volume is 100% contributing to renal function, but renal tumour contributes poorly. Instead, the perilesional rim of healthy tissue removed, which is rich in
Experts’ summary: In their retrospective single-institution study, the authors examined the contributions of functional parenchymal volume (FPV) preservation and warm ischemia time (WIT) to partial renal function after partial nephrectomy (PN). The hypothesis was that PN is still a challenging procedure due to the efforts made to shorten WIT, and perhaps FPV is the key factor in predicting functional outcomes. Data from 179 patients were extracted. Associations of WIT and percentage of FPV (%FPV) preservation with functional outcome were evaluated. Median WIT was 30 min, and FPV preservation was 97.4%. At 6 mo, median estimated glomerular filtration rate (eGFR) preservation was 93.1%. WIT was associated with percentage of eGFR (%eGFR) preservation at discharge; however, at 6-mo
EUROPEAN UROLOGY 69 (2016) 174–178
Re: Long-term Results of Thulium Laser Resection of the Prostate: A Prospective Study at Multiple Centers Sun F, Han B, Cui D, et al World J Urol 2015;33:503–8 Experts’ summary: In a retrospective, long-term, multisite study, Sun and colleagues demonstrated the safety, efficiency, and durability of thulium laser resection of prostate (TmLRP) in the treatment of benign prostatic hyperplasia (BPH). Of 2216 patients recruited at four medical centers, 541 (24.4%) were available for the longest follow-up period (8 yr). Compared with baseline, there were significant improvements in International Prostate Symptom Score, maximum urinary flow rate, quality of life, and postvoid residual urine by 3 mo after surgery and throughout the 8-yr follow-up period. Long-term complications were noted in 122 patients (5.5%): 58 (2.6%) had urethral stricture, 35 (1.6%) had bladder neck contracture, 2 (0.1%) had persistent stress incontinence, and 27 (1.2%) had BPH recurrence. Experts’ comments: The safety and efficacy of TmLRP as a minimally invasive procedure for the surgical treatment of BPH has been demonstrated by many clinical trials [1]. Compared with transurethral resection of the prostate (TURP), TmLRP has been shown to be superior with respect to hemostasis [2]. As emphasized by the authors, however, the evidence regarding the long-term safety and efficacy of TmLRP is limited. Consequently, we congratulate the authors for conducting this study, which aimed to evaluate the long-term durability of TmLRP. Nevertheless, we would like to point out a few issues. First, although it has been shown that short-term resolution of symptoms is not associated with the percentage of prostate volume removed [3], many urologists still believe that, in the long-term, the resolution of symptoms is associated with the extent of resection [4]. Based on our experience with TURP and TmLRP, the loop electrode used for TURP easily removes more tissue and makes the surgical margin more regular compared with the laser fibers used for TmLRP, especially during resection of the part of the media lobes below the verumontanum level. This is due to the different shape of the instrument
Re: Shift Work and Prostate Cancer Incidence in Industrial Workers: A Historical Cohort Study in a German Chemical Company Hammer GP, Emrich K, Nasterlack M, Blettner M, Yong M Dtsch Arztebl Int 2015;112:463–70 Experts’ summary: In a their recent original article, Hammer and coworkers showed that shift workers do not develop prostate cancer (PCa) more frequently than their colleagues who work during the day. The aim of this case–control study was to investigate the incidence of PCa in a cohort of shift workers versus
used in TmLRP and TURP. We speculate that less tissue will be removed with TmLRP, and thus the long-term results of TmLRP would be worse than TURP. Future studies should directly evaluate the long-term outcomes of TURP versus TmLRP, and the residual prostatic weight and prostate-specific antigen levels should be included in the assessments. Second, this study is significantly limited by the fact that a large number of patients were lost to follow-up (75.6% at 8 yr); however, if the main reasons for the number of patients lost to follow-up were listed in the article, then it would be helpful in interpreting the results and drawing more convincing conclusions about the durability of TmLRP. In summary, we agree with the authors that TmLRP is a safe and effective procedure, but the long-term durability of TmLRP requires additional research. Conflicts of interest: The authors have nothing to disclose.
References [1] Zhu Y, Zhuo J, Xu D, et al. Thulium laser versus standard transurethral resection of the prostate for benign prostatic obstruction: a systematic review and meta-analysis. World J Urol 2015;33:509–15. [2] Xia SJ, Zhuo J, Sun XW, et al. Thulium laser versus standard transurethral resection of the prostate: a randomized prospective trial. Eur Urol 2008;53:382–9. [3] Hakenberg OW, Helke C, Manseck A, Wirth MP. Is there a relationship between the amount of tissue removed at transurethral resection of the prostate and clinical improvement in benign prostatic hyperplasia. Eur Urol 2001;39:412–7. [4] Bachmann A, Rieken M. Words of wisdom. Re: GreenLight laser (XPS) photoselective vapo-enucleation versus holmium laser enucleation of the prostate for the treatment of symptomatic benign prostate hyperplasia: a randomized controlled study. Eur Urol 2015;67:976. Hao Yan, Jing Li, Xin Cui, Tong-wen Ou* Department of Urology, Xuanwu Hospital, Capital Medical University, Beijing, People’s Republic of China *Corresponding author. Department of Urology, Xuanwu Hospital, Capital Medical University, 45 Changchun Street, Beijing, People’s Republic of China. E-mail address: [email protected] (T. Ou). http://dx.doi.org/10.1016/j.eururo.2015.10.033
day workers. The authors evaluated the personnel and health data of almost 28 000 employees of a chemical company in Rhineland-Palatinate, Germany, between 1995 and 2005. They found 146 new cases of PCa in 12 609 rotating shift workers and 191 cases in 15 219 daytime workers. The year of birth was similar between the two groups: 1960 in the first group and 1959 in the second. The shift workers did not have an elevated hazard ratio (HR) for PCa in comparison to the daytime workers (HR: 0.93 [95% confidence interval (CI), 0.73–1.18]). There was a nonsignificant increase in the risk of a diagnosis of stage T1 or T4 PCa (HR: 1.26 [95% CI, 0.44–3.86] vs 1.36 [95% CI, 0.25–6.18]) and a decreased risk for stages T2 and
176
EUROPEAN UROLOGY 69 (2016) 174–178
T3 (HR 0.84 [95% CI, 0.62–1.15] vs 0.90 [95% CI, 0.53–1.52]). The authors’ conclusion contradicted the findings of previous smaller studies, with fewer participants, on the same subject that had reported an increased risk of PCa for shift workers [1,2]. Experts’ comments: We would like to praise the authors who analysed the effect of shift work on PCa in a large number of participants with well-documented data and adequate methods. Although the International Agency for Research on Cancer classified shift work as a carcinogen, most of the evidence comes from basic science or animal experiments, and only a few reliable epidemiologic studies exist, namely, breast cancer in female nurses and flight attendants [3]. It is thought that desynchronisation of circadian rhythms (ie, by nocturnal light exposure) suppresses melatonin secretion, leading to the loss of prevention and inhibition of cancer growth factor secretion. Epidemiologic data have shown that shift workers are at an increased risk of cardiovascular disease and breast cancer [3]. PCa is a genetic and clinically heterogeneous disease, and although many gaps are now closed, many others are not. Family history, race/ethnicity, geography, diet, obesity, smoking, and chronic inflammation are well-recognised risk factors for PCa, but shift work is not, according to Hammer and colleagues. As urologists, we should not underestimate the issue behind this paper. The production and release of nearly all hormones exhibit diurnal timing patterned on an approximately 24-hour cycle. Life style and working factors, such as night shift work and sleep desyncronisation with a consequent exposure to light at night, that disrupt circadian rhythm may also alter endocrine function and possibly the regulation of sexual hormones that are also relevant to the aetiology of hormone-dependent PCa and erectile dysfunction. Salonia et al reported that sex steroids are independent
predictors of high-risk PCa, depicting a nonlinear U-shape [4]. On July 31, 2015, The Economist reported that although the latest euro-area figures show that the overall unemployment rate has crept down to 11.1% from its peak of 12.1% in April 2013, unemployment remains high, especially in south Europe. The situation could push male workers, coping with unemployment, to accept more and more shift jobs under poorly controlled rules. Despite the conclusions of Hammer et al, this might affect the epidemiology of urologic diseases. Conflict of interest: The authors have nothing to disclose.
References [1] Kubo T, Oyama I, Nakamura T, et al. Industry-based retrospective cohort study of the risk of prostate cancer among rotating-shift workers. Int J Urol 2011;18:206–11. [2] Conlon M, Lightfoot N, Kreiger N. Rotating shift work and risk of prostate cancer. Epidemiol 2007;18:182–3. [3] Golubnitschaja O, Yeghiazaryan K, Costigliola V, et al. Risk assessment, disease prevention and personalised treatments in breast cancer: is clinically qualified integrative approach in the horizon? EPMA J 2013;4:6. [4] Salonia A, Abdollah F, Capitanio U, et al. Serum sex steroids depict a nonlinear u-shaped association with high-risk prostate cancer at radical prostatectomy. Clin Cancer Res 2012;18:3648–57. Massimo Lazzeri*, Giorgio Guazzoni Department of Urology, Humanitas Clinical and Research Center, Humanitas University, Rozzano (Milan), Italy *Corresponding author. Department of Urology, Humanitas Clinical and Research Center, Humanitas University, via Manzoni 56, 20089 Rozzano (Milan), Italy. E-mail address: [email protected] (M. Lazzeri). http://dx.doi.org/10.1016/j.eururo.2015.10.034
Re: Residual Parenchymal Volume, Not Warm Ischemia Time, Predicts Ultimate Renal Functional Outcomes in Patients Undergoing Partial Nephrectomy Ginzburg S, Uzzo R, Walton J, et al
follow-up, both preoperative eGFR and %FPV preservation—but not WIT—had significant association with %eGFR preservation.
Urology 2015;86:300–6
Experts’ comments: A body of literature is emerging that identifies the degree of parenchymal preservation and the preoperative quality of the renal parenchyma as key factors affecting post-PN partial renal function [1,2]. This paper goes in that direction, but its message is very strong, thus the reader should bring some points into focus. First, even if the method used to estimate FPV preservation has been used previously [3], it offers an empirical assessment (tumour is not a sphere, and kidney is not a cylinder), and the precision of the estimation is strongly correlated to the lesion location. Second, with the proposed formula, we should assume that the endophytic percentage of the lesion subtracted from the whole parenchymal volume is 100% contributing to renal function, but renal tumour contributes poorly. Instead, the perilesional rim of healthy tissue removed, which is rich in
Experts’ summary: In their retrospective single-institution study, the authors examined the contributions of functional parenchymal volume (FPV) preservation and warm ischemia time (WIT) to partial renal function after partial nephrectomy (PN). The hypothesis was that PN is still a challenging procedure due to the efforts made to shorten WIT, and perhaps FPV is the key factor in predicting functional outcomes. Data from 179 patients were extracted. Associations of WIT and percentage of FPV (%FPV) preservation with functional outcome were evaluated. Median WIT was 30 min, and FPV preservation was 97.4%. At 6 mo, median estimated glomerular filtration rate (eGFR) preservation was 93.1%. WIT was associated with percentage of eGFR (%eGFR) preservation at discharge; however, at 6-mo