There is growing interest from the oncology community to understand how body composition measures can be used to improve the delivery of clinical care for the 18.1 million individuals diagnosed with cancer annually. Methods that distinguish muscle from subcutaneous and visceral adipose tissue, such as computed tomography (CT), may offer new insights of important risk factors and improved prognostication of outcomes over alternative measures such as body mass index. In a meta‐analysis of 38 studies, low muscle area assessed from clinically acquired CT was observed in 27.7% of patients with cancer and associated with poorer overall survival [hazard ratio: 1.44, 95% CI: 1.32–1.56]. Therapeutic interventions such as lifestyle and pharmacotherapy that modify all aspects of body composition and reduce the incidence of poor clinical outcomes are needed in patients with cancer. In a meta‐analysis of six randomized trials, resistance training exercise increased lean body mass assessed from dual‐energy X‐ray absorptiometry [mean difference (MD): +1.07 kg, 95% CI: 0.76–1.37; P < 0.001] and walking distance [MD: +143 m, 95% CI: 70–216; P < 0.001] compared with usual care control in patients with non‐metastatic cancer. In a meta‐analysis of five randomized trials, anamorelin (a ghrelin agonist) significantly increased lean body mass [MD: +1.10 kg, 95% CI: 0.35–1.85; P = 0.004] but did not improve handgrip strength [MD: 0.52 kg, 95% CI: −0.09–1.13; P = 0.09] or overall survival compared with placebo [HR: 0.99, 95% CI: 0.85–1.14; P = 0.84] in patients with advanced or metastatic cancer. Early screening to identify individuals with occult muscle loss, combined with multimodal interventions that include lifestyle therapy with resistance exercise training and dietary supplementation combined with pharmacotherapy, may be necessary to provide a sufficient stimulus to prevent or slow the cascade of tissue wasting. Rapid, cost‐efficient, and feasible methods to quantify muscle and adipose tissue distribution are needed if body composition assessment is to be integrated into large‐scale clinical workflows. Fully automated analysis of body composition from clinically acquired imaging is one example. The study of body composition is one of the most provocative areas in oncology that offers tremendous promise to help patients with cancer live longer and healthier lives.

Background: Muscle abnormalities such as low muscle mass and low muscle radiodensity are well known risk factors for unfavourable cancer prognosis. However, little is known in regard to the degree and impact of longitudinal changes in muscle mass and radiodensity within the context of cancer. Here, we explore the relationship between muscle wasting and mortality in a large population‐based study of patients with non‐metastatic colorectal cancer (CRC).Methods: A total of 1924 patients with stage I–III CRC who underwent surgical resection in the Kaiser Permanente Northern California Health System were included. Muscle mass and radiodensity were quantified using computed tomography images obtained at diagnosis and after approximately 14 months. Cox proportional‐hazards models were used to estimate hazard ratios for all‐cause mortality.Results: The hazard ratio for all‐cause mortality among patients with the largest deterioration in muscle mass (≥2 SD; ≥11.4% loss from baseline), as compared with those who remained stable (±1 SD; 0.0 ± 5.7%) was 2.15 [95% confidence interval (CI): 1.59–2.92; P < 0.001]. The hazard ratio for all‐cause mortality among patients who experienced the largest deterioration in muscle radiodensity (≥2 SD; ≥20.2% loss from baseline), as compared with those who remained stable (±1 SD; 0.0 ± 10.1%) was 1.61 (95% CI: 1.20–2.15; P = 0.002).Conclusions: In patients with stage I–III CRC, muscle wasting is a risk factor for mortality, independent of change in body mass and other body composition parameters.

The biological mechanisms through which physical activity reduces metastatic disease recurrence and mortality in cancer patients are not known. This review offers the hypothesis that physical activity reduces the risk of recurrence and mortality in cancer patients through two synergistic processes: 1) indirect (systemic) effects related to the host tumor microenvironment; and 2) direct (physical) effects on cancer cells.

Colorectal cancer (CRC) is the fourth most common malignant neoplasm in the United States.¹ Five-year survival for patients with CRC has increased by 33% over the past 4 decades.² Patients with CRC are now more susceptible to competing causes of morbidity and mortality, such as those from cardiovascular disease (CVD).^3,4 Patients with CRC are 2-fold to 4-fold more likely than individuals without a history of cancer to develop CVD.⁵ Given the high risk of CVD in patients with CRC, evidence is necessary to inform cardiovascular management in this susceptible population.

Background: The quantity and distribution of adipose tissue may be prognostic measures of mortality in colorectal cancer patients, and such associations may vary by patient sex. Methods: This cohort included 3262 stage I–III colorectal cancer patients. Visceral and subcutaneous adipose tissues were quantified using computed tomography. The primary endpoint was all-cause mortality. Restricted cubic splines estimated statistical associations with two-sided P values. Results: Visceral adipose tissue was prognostic of mortality in a reverse L-shaped pattern (nonlinear P = .02); risk was flat to a threshold (∼260 cm2) then increased linearly. Subcutaneous adipose tissue was prognostic of mortality in a J-shaped pattern (nonlinear P < .001); risk was higher at extreme (50 to ≤560 cm2). Patient sex modified the prognostic associations between visceral adipose tissue (Pinteraction = .049) and subcutaneous adipose tissue (Pinteraction = .04) with mortality. Among men, visceral adiposity was associated with mortality in a J-shaped pattern (nonlinear P = .003), whereas among women, visceral adiposity was associated with mortality in a linear pattern (linear P = .008). Among men, subcutaneous adiposity was associated with mortality in an L-shaped pattern (nonlinear P = .01), whereas among women, subcutaneous adiposity was associated with mortality in a J-shaped pattern (nonlinear P < .001). Conclusions: Visceral and subcutaneous adipose tissue were prognostic of mortality in patients with colorectal cancer; the shape of these associations were often nonlinear and varied by patient sex. These results offer insight into the potential biological mechanisms that link obesity with clinical outcomes in patients with cancer, suggesting that the dysregulated deposition of excess adiposity is prognostic of mortality.