Affiliations of authors: Center for Clinical Epidemiology and Biostatistics, Abramson Cancer Center Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA (KHS, LTD); Division of Public Health Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA (MLN); Division of Cancer Control and Population Sciences, National Cancer Institute, Bethesda, MD (TA-C, KAZ); Moores Cancer Center, University of California, San Diego, CA (LC-B); Department of Surgery, Washington University, St. Louis, MO (BFD).
J Natl Cancer Inst. 2013 Sep 18;105(18):1344-54. doi: 10.1093/jnci/djt223. Epub 2013 Aug 29.
Evidence that obesity is associated with cancer incidence and mortality is compelling. By contrast, the role of obesity in cancer survival is less well understood. There is inconsistent support for the role of obesity in breast cancer survival, and evidence for other tumor sites is scant. The variability in findings may be due in part to comorbidities associated with obesity itself rather than with cancer, but it is also possible that obesity creates a physiological setting that meaningfully alters cancer treatment efficacy. In addition, the effects of obesity at diagnosis may be distinct from the effects of weight change after diagnosis. Obesity and related comorbid conditions may also increase risk for common adverse treatment effects, including breast cancer-related lymphedema, fatigue, poor health-related quality of life, and worse functional health. Racial and ethnic groups with worse cancer survival outcomes are also the groups for whom obesity and related comorbidities are more prevalent, but findings from the few studies that have addressed these complexities are inconsistent. We outline a broad theoretical framework for future research to clarify the specifics of the biological-social-environmental feedback loop for the combined and independent contributions of race, comorbid conditions, and obesity on cancer survival and adverse treatment effects. If upstream issues related to comorbidities, race, and ethnicity partly explain the purported link between obesity and cancer survival outcomes, these factors should be among those on which interventions are focused to reduce the burden of cancer.
有充分证据表明肥胖与癌症发病率和死亡率有关。相比之下，肥胖对癌症生存的作用则知之甚少。肥胖对乳腺癌生存的作用存在不一致的支持，而其他肿瘤部位的证据则很少。研究结果的可变性部分可能归因于与肥胖本身而非癌症相关的合并症，但也有可能肥胖会创造出一种生理环境，从而显著改变癌症治疗的效果。此外，诊断时的肥胖与诊断后的体重变化的影响可能不同。肥胖和相关的合并症也可能增加常见不良治疗效果的风险，包括乳腺癌相关的淋巴水肿、疲劳、健康相关生活质量差和功能健康状况恶化。癌症生存结果较差的种族和族裔群体中肥胖和相关合并症也更为普遍，但为数不多的研究结果也不一致。我们提出了一个广泛的理论框架，用于未来的研究，以阐明种族、合并症和肥胖对癌症生存和不良治疗效果的综合和独立影响的生物-社会-环境反馈回路的具体情况。如果与合并症、种族和族裔有关的上游问题部分解释了肥胖与癌症生存结果之间的所谓联系，那么这些因素应该是干预的重点，以减轻癌症的负担。
