Sarcopenia in Older Adults with Hematologic Malignancies: A Comprehensive Review of Epidemiology, Prognosis, and Interventions

Hematologic malignancies, including leukemias, lymphomas, and multiple myeloma, are diseases of older adults (age ≥ 60 years). Treatment decisions in older adults with cancer are heavily influenced by patient fitness: the ability of an individual patient to tolerate the off-target effects of anti-cancer therapy. Sarcopenia, defined as low muscle mass and strength, is increasingly recognized as an important marker of fitness. Furthermore, sarcopenia is known to be modifiable with nutrition and exercise interventions in older adults without cancer, but such evidence is limited for patients with cancer. Much of the literature on sarcopenia in older adults with cancer has focused on patients with solid tumors. However, there is an increasing body of literature on the impact of sarcopenia in older adults with hematologic malignancies. In this comprehensive review, we attempt to (i) describe the most up-to-date diagnostic criteria and diagnostic approach to sarcopenia, (ii) summarize the prognostic impact of sarcopenia among older adults with hematologic malignancies, (iii) discuss the proposed mechanisms of sarcopenia and its pathogenesis, (iv) review the evidence for interventions targeting sarcopenia, and (v) provide future directions for the advancement of sarcopenia management among older adults with hematologic malignancies.