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Weight Lifting for Women at Risk for Breast Cancer–Related Lymphedema: A Randomized Trial
GENERAL ISSUES IN BREAST CANCER Weight Lifting for Women at Risk for Breast Cancer–Related Lymphedema: A Randomized Trial Schmitz KH, Ahmed RL, Troxel AB, et al (Univ of Pennsylvania School of Medicine and Abramson Cancer Ctr, Philadelphia; Univ of Minnesota Med School, Minneapolis; et al) JAMA 304:2699-2705, 2010
Context.—Clinical guidelines for breast cancer survivors without lymphedema advise against upper body exercise, preventing them from obtaining established health benefits of weight lifting. Objective.—To evaluate lymphedema onset after a 1-year weight lifting intervention vs no exercise (control) among survivors at risk for breast cancer–related lymphedema (BCRL). Design, Setting, and Participants.— A randomized controlled equivalence trial (Physical Activity and Lymphedema trial) in the Philadelphia metropolitan area of 154 breast cancer survivors 1 to 5 years postunilateral breast cancer, with at least 2 lymph nodes removed and without clinical signs of BCRL at study entry. Participants were recruited between October 1, 2005, and February 2007, with data collection ending in August 2008. Intervention.—Weight lifting intervention included a gym membership and 13 weeks of supervised instruction, with the remaining 9 months unsupervised, vs no exercise. Main Outcome Measures.—Incident BCRL determined by increased arm swelling during 12 months ($5% increase in interlimb difference). Clinician-defined BCRL onset was also
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evaluated. Equivalence margin was defined as doubling of lymphedema incidence. Results.—A total of 134 participants completed follow-up measures at 1 year. The proportion of women who experienced incident BCRL onset was 11% (8 of 72) in the weight lifting intervention group and 17% (13 of 75) in the control group (cumulative incidence difference [CID], 6.0%; 95% confidence interval [CI], 17.2% to 5.2%; P for equivalence ¼ .04). Among women with 5 or more lymph nodes removed, the proportion who experienced incident BCRL onset was 7% (3 of 45) in the weight lifting intervention group and 22% (11 of 49) in the control group (CID, 15.0%; 95% CI, 18.6% to 11.4%; P for equivalence ¼ .003). Clinician-defined BCRL onset occurred in 1 woman in the weight lifting intervention group and 3 women in the control group (1.5% vs 4.4%, P for equivalence ¼ .12). Conclusion.—In breast cancer survivors at risk for lymphedema, a program of slowly progressive weight lifting compared with no exercise did not result in increased incidence of lymphedema. Trial Registration.—clinicaltrials. gov Identifier: NCT00194363. Schmitz and colleagues have shed new light on the benefits of resistance training, particularly progressive weight training, for breast cancer survivors at risk for lymphedema. For far too long, breast cancer survivors have been encouraged to engage in less activity and limit the use of the affected arm out of fear of developing the condition and uncertainty about personal risk and safety. However, such advice often results in physical
Breast Diseases: A Year BookÒ Quarterly Vol 22 No 2 2011
deconditioning of the arm1 and prevents breast cancer survivors from reaping the benefits of increased activity. In this study, Schmitz and colleagues provide compelling evidence that properly designed, supervised progressive weight training is not only safe but also may be protective against developing lymphedema. It is important to note that lymphedema is now and will continue to be a frequent and serious unwanted complication for breast cancer survivors, even those who undergo sparing procedures, such as sentinel node biopsy. Therefore, the importance of research aimed at finding effective modalities that reduce the likelihood of lymphedema while enhancing survivors’ physical and mental wellbeing cannot be overstated. This study is the latest in a continuum of research conducted by Schmitz and colleagues on the efficacy of weight training for lymphedema. In the initial pilot study, the team found no evidence that a 6-month progressive weight lifting program among breast cancer survivors (n ¼ 45) precipitated lymphedema incidence or worsened symptoms of those with lymphedema.2 Previously published results for the current study3 showed favorable results: increased strength, reduced symptoms, and decreased incidence of exacerbation of lymphedema in 145 breast cancer survivors with stable arm lymphedema enrolled in a 1-year progressive weight lifting randomized controlled trial. Continuing with this study, the team assessed the 1-year progressive weight lifting randomized controlled trial results of 154 breast cancer survivors without clinical signs of breast cancer–related lymphedema. Survivors in the intervention group
participated in 13 weeks of supervised exercise sessions and twice-weekly unsupervised sessions thereafter for up to 1 year. Fitness trainers were available to help participants adhere to the exercise plan, safely increase or decrease weight, and monitor arm swelling. Control group participants received part of the intervention (gym membership and 13 weeks of supervised exercise sessions) after the 1-year study period. The team found no evidence that breast cancer survivors who engaged in weight lifting were at increased risk of lymphedema. It is important to note some of the strengths of this study. First, intensive and comprehensive training the trainers on the progressive weight lifting protocol, followed by a period of checking for protocol fidelity, greatly enhanced the safety and internal validity of the study. Second, the program was not only progressive (ie, weight was increased after participants successfully managed a given weight) but was also regressive, that is, participants regressed to a lower weight if they missed a set number of sessions. Third, progression from supervised sessions in small groups for the first 13 weeks to independent sessions for the remainder of the study period most likely enhanced the participants’ perceived efficacy to perform the weight training and contributed to the high completion rate over a 1-year period.
The strengths should be viewed with the consideration of some limitations. Lymphedema can suddenly occur years after treatment,4 often with no clear precipitating factor.5 Therefore, longer-term studies involving weight training with very long follow-up are needed in the future. In addition, as the authors pointed out, corresponding gains in strength were not directly explainable by changes in lean mass. It may be that most of the gains in strength were the results of neuromuscular recruitment mechanisms rather than incremental gains in lean mass. Again, more research is needed. Last, future research might be conducted in lowincome and/or ethnic minority breast cancer survivors, as women in this sample were well-educated, selfmotivated, and primarily non-Hispanic white (with a small number of African Americans). The primary objective of this pivotal study was to test the safety of a properly designed 1-year progressive weight lifting program for breast cancer survivors who underwent axillary lymph node dissection. This study, consistent with earlier work, provides strong evidence that breast cancer survivors can confidently participate in weight training and thus gain the benefits of such a program (strength, body mass changes, etc). Still, as the authors have correctly
pointed out, additional research is needed before we can convincingly say that resistance training prevents lymphedema. The authors should be lauded for their continued exemplary research and are urged to continue providing scientific evidence of the efficacy of properly designed exercise for women at risk for lymphedema.
Safety of pregnancy following breast cancer diagnosis: A meta-analysis of 14 studies
Eur J Cancer 47:74-83, 2011
following breast cancer diagnosis is on the rise. Available evidence suggests that women with a history of breast cancer are frequently advised against future conception for fear that pregnancy could adversely affect their breast cancer outcome. Hence, we conducted a meta-analysis to understand the effect
Azim HA Jr, Santoro L, Pavlidis N, et al (Jules Bordet Inst, Brussels, Belgium; European Inst of Oncology, Milan, Italy; Univ of Ioannina, Greece; et al)
Background.—Due to the rising trend of delaying pregnancy to later in life, more women are diagnosed with breast cancer before completing their families. Therefore, enquiry into the feasibility and safety of pregnancy
D. C. Hughes, PhD C. M. Mojica, PhD
References 1. Schmitz KH. Balancing lymphedema risk: exercise versus deconditioning for breast cancer survivors. Exerc Sport Sci Rev. 2010;38:17-24. 2. Ahmed RL, Thomas W, Yee D, Schmitz KH. Randomized controlled trial of weight training and lymphedema in breast cancer survivors. J Clin Oncol. 2006;24: 2765-2772. 3. Schmitz KH, Ahmed RL, Troxel A, et al. Weight lifting in women with breast-cancer-related lymphedema. N Engl J Med. 2009;361:664-673. 4. Petrek JA, Heelan MC. Incidence of breast carcinoma-related lymphedema. Cancer. 1998;83: 2776-2881. 5. Rockson SG. Precipitating factors in lymphedema: myths and realities. Cancer. 1998;83:2814-2816.
Breast Diseases: A Year BookÒ Quarterly Vol 22 No 2 2011
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Context.—Clinical guidelines for breast cancer survivors without lymphedema advise against upper body exercise, preventing them from obtaining established health benefits of weight lifting. Objective.—To evaluate lymphedema onset after a 1-year weight lifting intervention vs no exercise (control) among survivors at risk for breast cancer–related lymphedema (BCRL). Design, Setting, and Participants.— A randomized controlled equivalence trial (Physical Activity and Lymphedema trial) in the Philadelphia metropolitan area of 154 breast cancer survivors 1 to 5 years postunilateral breast cancer, with at least 2 lymph nodes removed and without clinical signs of BCRL at study entry. Participants were recruited between October 1, 2005, and February 2007, with data collection ending in August 2008. Intervention.—Weight lifting intervention included a gym membership and 13 weeks of supervised instruction, with the remaining 9 months unsupervised, vs no exercise. Main Outcome Measures.—Incident BCRL determined by increased arm swelling during 12 months ($5% increase in interlimb difference). Clinician-defined BCRL onset was also
124
evaluated. Equivalence margin was defined as doubling of lymphedema incidence. Results.—A total of 134 participants completed follow-up measures at 1 year. The proportion of women who experienced incident BCRL onset was 11% (8 of 72) in the weight lifting intervention group and 17% (13 of 75) in the control group (cumulative incidence difference [CID], 6.0%; 95% confidence interval [CI], 17.2% to 5.2%; P for equivalence ¼ .04). Among women with 5 or more lymph nodes removed, the proportion who experienced incident BCRL onset was 7% (3 of 45) in the weight lifting intervention group and 22% (11 of 49) in the control group (CID, 15.0%; 95% CI, 18.6% to 11.4%; P for equivalence ¼ .003). Clinician-defined BCRL onset occurred in 1 woman in the weight lifting intervention group and 3 women in the control group (1.5% vs 4.4%, P for equivalence ¼ .12). Conclusion.—In breast cancer survivors at risk for lymphedema, a program of slowly progressive weight lifting compared with no exercise did not result in increased incidence of lymphedema. Trial Registration.—clinicaltrials. gov Identifier: NCT00194363. Schmitz and colleagues have shed new light on the benefits of resistance training, particularly progressive weight training, for breast cancer survivors at risk for lymphedema. For far too long, breast cancer survivors have been encouraged to engage in less activity and limit the use of the affected arm out of fear of developing the condition and uncertainty about personal risk and safety. However, such advice often results in physical
Breast Diseases: A Year BookÒ Quarterly Vol 22 No 2 2011
deconditioning of the arm1 and prevents breast cancer survivors from reaping the benefits of increased activity. In this study, Schmitz and colleagues provide compelling evidence that properly designed, supervised progressive weight training is not only safe but also may be protective against developing lymphedema. It is important to note that lymphedema is now and will continue to be a frequent and serious unwanted complication for breast cancer survivors, even those who undergo sparing procedures, such as sentinel node biopsy. Therefore, the importance of research aimed at finding effective modalities that reduce the likelihood of lymphedema while enhancing survivors’ physical and mental wellbeing cannot be overstated. This study is the latest in a continuum of research conducted by Schmitz and colleagues on the efficacy of weight training for lymphedema. In the initial pilot study, the team found no evidence that a 6-month progressive weight lifting program among breast cancer survivors (n ¼ 45) precipitated lymphedema incidence or worsened symptoms of those with lymphedema.2 Previously published results for the current study3 showed favorable results: increased strength, reduced symptoms, and decreased incidence of exacerbation of lymphedema in 145 breast cancer survivors with stable arm lymphedema enrolled in a 1-year progressive weight lifting randomized controlled trial. Continuing with this study, the team assessed the 1-year progressive weight lifting randomized controlled trial results of 154 breast cancer survivors without clinical signs of breast cancer–related lymphedema. Survivors in the intervention group
participated in 13 weeks of supervised exercise sessions and twice-weekly unsupervised sessions thereafter for up to 1 year. Fitness trainers were available to help participants adhere to the exercise plan, safely increase or decrease weight, and monitor arm swelling. Control group participants received part of the intervention (gym membership and 13 weeks of supervised exercise sessions) after the 1-year study period. The team found no evidence that breast cancer survivors who engaged in weight lifting were at increased risk of lymphedema. It is important to note some of the strengths of this study. First, intensive and comprehensive training the trainers on the progressive weight lifting protocol, followed by a period of checking for protocol fidelity, greatly enhanced the safety and internal validity of the study. Second, the program was not only progressive (ie, weight was increased after participants successfully managed a given weight) but was also regressive, that is, participants regressed to a lower weight if they missed a set number of sessions. Third, progression from supervised sessions in small groups for the first 13 weeks to independent sessions for the remainder of the study period most likely enhanced the participants’ perceived efficacy to perform the weight training and contributed to the high completion rate over a 1-year period.
The strengths should be viewed with the consideration of some limitations. Lymphedema can suddenly occur years after treatment,4 often with no clear precipitating factor.5 Therefore, longer-term studies involving weight training with very long follow-up are needed in the future. In addition, as the authors pointed out, corresponding gains in strength were not directly explainable by changes in lean mass. It may be that most of the gains in strength were the results of neuromuscular recruitment mechanisms rather than incremental gains in lean mass. Again, more research is needed. Last, future research might be conducted in lowincome and/or ethnic minority breast cancer survivors, as women in this sample were well-educated, selfmotivated, and primarily non-Hispanic white (with a small number of African Americans). The primary objective of this pivotal study was to test the safety of a properly designed 1-year progressive weight lifting program for breast cancer survivors who underwent axillary lymph node dissection. This study, consistent with earlier work, provides strong evidence that breast cancer survivors can confidently participate in weight training and thus gain the benefits of such a program (strength, body mass changes, etc). Still, as the authors have correctly
pointed out, additional research is needed before we can convincingly say that resistance training prevents lymphedema. The authors should be lauded for their continued exemplary research and are urged to continue providing scientific evidence of the efficacy of properly designed exercise for women at risk for lymphedema.
Safety of pregnancy following breast cancer diagnosis: A meta-analysis of 14 studies
Eur J Cancer 47:74-83, 2011
following breast cancer diagnosis is on the rise. Available evidence suggests that women with a history of breast cancer are frequently advised against future conception for fear that pregnancy could adversely affect their breast cancer outcome. Hence, we conducted a meta-analysis to understand the effect
Azim HA Jr, Santoro L, Pavlidis N, et al (Jules Bordet Inst, Brussels, Belgium; European Inst of Oncology, Milan, Italy; Univ of Ioannina, Greece; et al)
Background.—Due to the rising trend of delaying pregnancy to later in life, more women are diagnosed with breast cancer before completing their families. Therefore, enquiry into the feasibility and safety of pregnancy
D. C. Hughes, PhD C. M. Mojica, PhD
References 1. Schmitz KH. Balancing lymphedema risk: exercise versus deconditioning for breast cancer survivors. Exerc Sport Sci Rev. 2010;38:17-24. 2. Ahmed RL, Thomas W, Yee D, Schmitz KH. Randomized controlled trial of weight training and lymphedema in breast cancer survivors. J Clin Oncol. 2006;24: 2765-2772. 3. Schmitz KH, Ahmed RL, Troxel A, et al. Weight lifting in women with breast-cancer-related lymphedema. N Engl J Med. 2009;361:664-673. 4. Petrek JA, Heelan MC. Incidence of breast carcinoma-related lymphedema. Cancer. 1998;83: 2776-2881. 5. Rockson SG. Precipitating factors in lymphedema: myths and realities. Cancer. 1998;83:2814-2816.
Breast Diseases: A Year BookÒ Quarterly Vol 22 No 2 2011
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