The association of body composition parameters and adverse events in women receiving chemotherapy for early breast cancer

BACKGROUND

Body composition metrics as predictors of adverse events are a growing area of interest in oncology research. One barrier to the use of these metrics in clinical practice is the lack of standardized cut points for identifying patients with at-risk body composition profiles. We examined the association of chemotherapy adverse events with several body composition measures, using alternative cut points from published studies.

METHODS

This is a retrospective study of women diagnosed with early breast cancer (EBC). Axial computerized tomography (CT) images from lumbar L3 segments were analyzed for the following body composition measures: myosteatosis (low Skeletal Muscle Density/SMD), sarcopenia (low Skeletal Muscle Index/SMI), and high Visceral Adipose Tissue (VAT). Adverse events during chemotherapy were dose reduction, early treatment discontinuation, and hospitalization. Log-binomial modeling was used to evaluate associations between body composition measures at different cut points with adverse events, adjusting for age, race, Body Mass Index/BMI, and comorbidities. Relative risks were reported as the measure of association.

RESULTS

In a sample of 338 women, mean age was 51, 14% were age 65 or older, 32% were non-white, 40% had obesity (/BMI ≥ 30 kg/m²), and mean number of comorbidities was 1.56. In multivariable analysis (MV), all three SMD cut points for myosteatosis had significant associations with total number of adverse events, as well as different cut points having significant associations with either dose reduction, early treatment discontinuation or hospitalization. SMI and VAT were not significant in the MV analysis; however, in some models, age and total comorbidities were significant for adverse events.

CONCLUSIONS

Among CT-derived measures of body composition, myosteatosis determined at any of three SMD cut points was associated with total and individual adverse events during chemotherapy for early breast cancer.

Association of body composition with function in women with early breast cancer

BACKGROUND

Advances in breast cancer research are making treatment options increasingly effective and reducing mortality. Body composition is an example of a prognostic tool that can help personalize breast cancer treatments and further increase their effectiveness. In this study, we examine the association of several body composition measures with comorbidities, physical function, and quality of life.

METHODS

This study is a cross-sectional analysis of 99 women with early breast cancer scheduled for chemotherapy. Univariate regression models were used to identify significant associations of body composition metrics with patient demographics, clinical characteristics, measures of physical function, and patient-reported outcomes (PRO)s. Multivariable modeling was used to evaluate associations adjusted for age.

RESULTS

Median age was 58 (range 24-83), 27% were non-white, and, 47% were obese (≥ 30 kg/m2). Increasing age was associated with lower Skeletal Muscle Density (SMD) (p = 0.0001), lower Skeletal Muscle Gauge (SMG) (p = 0.0005), and higher Visceral Adipose Tissue (VAT) (p < 0.0001). In patients with a prolonged Timed Up and Go tests (> 14 s), mean VAT was 57.87 higher (p = 0.004), SMD 5.70 lower (p = 0.04), and SMG 325.4 lower (p = 0.02). For each point of higher performance on the Short Physical Performance Battery (SPPB), VAT decreased 12.24 (p = 0.002) and SMD rose 1.22 (p = 0.02). In multivariable analysis adjusting for age, the association of TUG > 14 with higher VAT remained significant (p = 0.02).

CONCLUSIONS

Suboptimal body composition prior to treatment is associated poor physical function and may be an indicator of clinical importance.

Myosteatosis and prognosis in cancer: Systematic review and meta-analysis

BACKGROUND

The evidence that body composition parameters influence multiple cancer outcomes is rapidly expanding. Excess adiposity deposits in muscle tissue, termed myosteatosis, can be detected in CT scans through variations in the density of muscle tissues (Hounsfield Units). Patients with similar muscle mass but different amounts of intramuscular adipose infiltration have increased chemotherapy toxicity, time to tumor progression and other adverse outcomes among different cancer types. Our review examines the impact of myosteatosis on overall survival (OS) in patients with cancer.

METHODS

A systematic search of the literature was conducted on PubMed/ MEDLINE, Cochrane CENTRAL, and EMBASE. Meta-analysis was conducted using a random-effects model. Risk of bias was evaluated using the Newcastle-Ottawa Quality assessment for cohort studies, funnel plot (publication bias), and GRADE summary of findings tool from Cochrane.

RESULTS

A total of 4880 articles were screened from which 40 articles selected, including 21,222 patients. The overall mean proportion of patients with myosteatosis was 48 % (range 11-85 %). Using skeletal muscle density (SMD), patients classified as having myosteatosis had 75 % greater mortality risk compared to non-myosteatosis patients (HR 1.75 95 % CI 1.60-1.92, 40 studies) (p < .00001) (i2 = 62 %). Specifically, myosteatosis was prognostic for worse OS in patients with gynecological, renal, periampullary/pancreatic, hepatocellular, gastroesophageal, and colorectal carcinoma, and lymphomas.

CONCLUSION

Our analysis of the literature shows that cancer patients with myosteatosis have shorter survival. Our findings suggest that in oncological practice, muscle density assessment is valuable as a prognostic parameter.

Muscle composition and outcomes in patients with breast cancer: meta-analysis and systematic review

PURPOSE

Breast cancer is the most common cancer and leading cause of cancer death in women. Body composition parameters, especially those related to muscle, have become a growing focus of cancer research. In this review, we summarize the literature on breast cancer and muscle parameters as well as combine their outcomes for overall survival (OS), time to tumor progression (TTP), and chemotherapy toxicity in a meta-analysis.

METHODS

A systematic search of the literature for randomized controlled trials and observational studies was conducted on MEDLINE, Cochrane CENTRAL, and EMBASE through May 1, 2019. Two reviewers independently searched and selected. Meta-analysis was conducted using a random-effects model. The risk of bias was evaluated using the Newcastle-Ottawa quality assessment for cohorts and GRADE summary of findings tool from Cochrane.

RESULTS

A total of 754 articles were screened from which 6 articles and one abstract were selected. Using skeletal muscle index (SMI), patients classified as sarcopenic had a 68% greater mortality risk compared to non-sarcopenic patients (HR 1.68 95% CI 1.09-2.59, 5 studies) (p = .02) (i² = 70%). Low muscle density was not predictive of OS (HR 1.44 95% CI 0.77-2.68, 2 studies) (p = .25) (i² = 87%). Patients with sarcopenia (56%) had more grade 3-5 toxicity compared to non-sarcopenic (25%) (RR 2.17 95% CI 1.4-3.34, 3 studies) (p = .0005) (i² = 0%). TTP was nearly 71 days longer in advanced/metastatic patients classified as non-sarcopenic compared to patients with sarcopenia (MD - 70.75 95% CI - 122.32 to - 19.18) (p = .007) (i² = 0%).

CONCLUSION

Our synthesis of the literature shows that patients with sarcopenia have more severe chemotherapy toxicity as well as shorter OS and TTP, and that low muscle density is prognostic of OS for women with metastatic breast cancer. Our findings suggest that in clinical practice, body composition assessment is valuable as a prognostic parameter in breast cancer.