Low skeletal muscle mass predicts treatment response in oncology: a meta-analysis

Objectives: Low skeletal muscle mass (LSMM) predicts relevant clinical outcomes in oncologic patients. The purpose of this study was to perform a meta-analysis of data regarding associations between LSMM and treatment response (TR) in oncology.

Methods: MEDLINE, Cochrane, and SCOPUS databases were screened for relationships between LSMM and TR in oncologic patients up to November 2022. Overall, 35 studies met the inclusion criteria. The meta-analysis was performed using RevMan 5.4 software.

Results: The collected 35 studies comprised 3858 patients. In 1682 patients (43.6%), LSMM was diagnosed. In the overall sample, LSMM predicted a negatively objective response rate (ORR), OR = 0.70, 95% CI = (0.54-0.91), p = 0.007, and disease control rate (DCR), OR = 0.69, 95% CI = (0.50-0.95), p = 0.02. In the curative setting, LSMM predicted a negatively ORR, OR = 0.24, 95% CI = (0.12-0.50), p = 0.0001, but not DCR, OR = 0.60, 95% CI = (0.31-1.18), p = 0.14. In palliative treatment with conventional chemotherapies, LSMM did not predict ORR: OR = 0.94, 95% CI (0.57-1.55), p = 0.81, and DCR: OR = 1.13, 95% CI (0.38-3.40), p = 0.82. In palliative treatment with tyrosine kinase inhibitors (TKI), LSMM did not predict TR: ORR, OR = 0.74, 95% CI (0.44-1.26), p = 0.27, and DCR, OR = 1.04, 95% CI (0.53-2.05), p = 0.90. In palliative immunotherapy, LSMM tended to predict ORR, OR = 0.74, 95% CI = (0.54-1.01), p = 0.06, and predicted DCR, OR = 0.53, 95% CI = (0.37-0.76), p = 0.0006.

Conclusion: LSMM is a risk factor for poor TR in curative chemotherapy in the adjuvant and/or neoadjuvant setting. LSMM is a risk factor for treatment failure in treatment with immunotherapy. Finally, LSMM does not influence TR in palliative treatment with conventional chemotherapy and/or TKIs.

Key points: • Low skeletal muscle mass (LSMM) predicts treatment response (TR) to chemotherapy in the adjuvant and/or neoadjuvant setting. • LSMM predicts TR in immunotherapy. • LSMM does not influence TR in palliative chemotherapy.