A significant decrease in muscle area was seen in patients with metastatic colorectal cancer (mCRC) receiving chemotherapy, and was independently associated with survival in these patients, a study published online ahead of print in the Journal of Clinical Oncology has shown.1
Approximately 40% of patients with mCRC experience loss of muscle mass. To determine the impact of this effect on outcome, the researchers studied change in skeletal muscle during palliative chemotherapy in patients with mCRC.
For this study, researchers used CT scans of the third lumbar vertebra obtained before and during palliative chemotherapy to assess muscle area (square centimeters) in 67 patients with mCRC. They also used multiple regression analyses to evaluate treatment modifications resulting from toxicity, including delay, dose reduction, or termination of chemotherapy, and secondly overall survival.
The researchers observed a decrease of 6.1% in muscle area of patients with mCRC during 3 months of chemotherapy (95% CI, −8.4 to −3.8; P<.001), and the effect was not associated with treatment modifications. Survival rates were lower for patients with muscle loss during treatment of 9% or more compared with patients with muscle loss of less than 9%: 33% vs 69% of patients were alive at 6 months; 17% vs 49% of patients were alive at 1 year (log-rank P=.001).
Furthermore, after adjustments for sex, age, baseline lactate dehydrogenase concentration, comorbidity, mono-organ or multiorgan metastases, treatment line, and tumor progression at first evaluation by CT scan, muscle loss of 9% or more remained independently associated with survival (hazard ratio, 4.47; 95% CI, 2.21 to 9.05; P<.001).
“Further clinical evaluation is required to determine whether nutritional interventions and exercise training may preserve muscle area and thereby improve outcome,” the researchers report.
1. Blauwhoff-Buskermolen S, Versteeg KS, de van der Schueren MA, et al. Loss of muscle mass during chemotherapy is predictive for poor survival of patients with metastatic colorectal cancer [published online ahead of print February 22, 2016]. J Clin Oncol. doi:10.1200/JCO.2015.63.6043.