The relationship between medical therapy and sarcopenia in advanced non-small cell lung cancer patients

Aims: Sarcopenia, characterized by loss of skeletal muscle mass and function, is associated with worse clinical outcomes in cancer patients. Cancer treatment may influence the development of sarcopenia. On the other hand, the presence of sarcopenia before or after treatment may affect the response to cancer therapy. This vicious circle is associated with a higher mortality risk. The aim of this study was to determine the prevalence of sarcopenia in newly diagnosed advanced non-small cell lung cancer (NSCLC) patients before and after standard chemotherapy protocols and to investigate the relationship between sarcopenia and treatment response. Methods: Between October 13, 2022, and February 13, 2023, 38 patients over 18 years of age with advanced NSCLC who were admitted to the Medical Oncology Department Outpatient Clinic were included in the study. Bioelectrical impedance analysis (BIA) and anthropometric measurements were performed in all patients. Hand squeeze strength measured with an electronic hand dynamometer was used to assess muscle strength. Muscle performance was assessed by walking speed measured on a 4-meter track. Walking speed <0.8 m/sec was considered in favor of decreased muscle performance. The diagnosis of sarcopenia was based on the criteria of the EWGSOP study group's criteria were used to diagnose sarcopenia. Results: Before treatment, 23.7% of patients had probable sarcopenia, 10.5% had sarcopenia, and 15.8% had severe sarcopenia. Sarcopenia developed in 21.1% of patients without sarcopenia before treatment, while 21.1% of patients with possible sarcopenia developed severe sarcopenia after treatment. The ECOG performance score and saturation level worsened in patients with increased sarcopenia after treatment. Thirty percent of patients with pre-treatment sarcopenia died after treatment, and progression was detected in all of the remaining patients after treatment. In patients whose sarcopenia score did not change after treatment, there was no significant difference in BIA parameters after treatment, while vitamin D levels increased. In patients whose sarcopenia score increased after treatment, there was a significant decrease in lean weight and lean mass index, as well as a decrease in vitamin D level. Adenocarcinoma subtype, Stage 4, and platinum-based chemotherapy were associated with an increase in the post-treatment sarcopenia score. Conclusion: The prevalence of sarcopenia in NSCLC patients is approximately 50%, and disease stage, type, and treatment regimen play an important role in the development of sarcopenia. The presence of sarcopenia before treatment may have an impact on treatment response and increase the risk of chemotherapy-related toxicity. It is also associated with a higher mortality risk.