The prevalence and the impact of sarcopenia in digestive cancers. A systematic review.

Introduction: Sarcopenia is characterized by a decrease in skeletal muscle mass, associated with low muscle strength and/or poor physical performance. Assessing the prevalence of sarcopenia among digestive cancers and establishing the impact that sarcopenia has on the postoperative evolution of digestive tumors may be a central pillar in improving postoperative outcomes by caring for perioperative sarcopenia. This brief review aimed to evaluate the prevalence of sarcopenia in digestive cancer patients. Method and materials: PubMed database was searched for "sarcopenia" AND "digestive cancers" from January 1st, 2010, through September 30th, 2020. PRISMA guideline was used for this systematic review. After the selection process, 31 complete studies were included in our review. Assessment of sarcopenia diagnosis for the studies included in this systematic review was based on a computed tomographic calculation of the skeletal muscle index at the third lumbar vertebra. Results: Among a total of 11,651 patients with digestive cancers, the prevalence of sarcopenia was 43.68%. The highest prevalence of sarcopenic patients was in esophageal (70.4%) and hepatic (60.3%) cancer, following by biliary tract (49.3%), pancreatic (45.70%), colorectal (42.83%) cancer, and gastric cancer (32.05%) with the lowest prevalence. The results of the studies conducted by now regarding the prevalence of sarcopenia in digestive cancers and its relevance in the evolution of these cancers are discordant and uneven. Some studies show that the presence of sarcopenia in patients with digestive cancers is associated with an increased rate of postoperative complications, increased toxicity of chemotherapeutics and increased mortality. Other studies do not find sarcopenia as an independent risk factor associated with negative consequences in the course of patients with digestive cancers. Conclusions: Sarcopenia is prevalent in digestive cancers. There is still no consensus about the impact of sarcopenia on the treatment of digestive cancers. Further studies are needed to evaluate the real consequences of sarcopenia in digestive cancers..