The relationship between sarcopenia detected in newly diagnosed lung cancer patients and serum levels of IL6, IGF-1 and myostatin.

Aim: Sarcopenia can result from many factors, including cancer, and is a consequence of quantitative and qualitative deterioration in skeletal muscle mass. Although there are some hypothetical explanations for sarcopenia, the underlying mechanisms of this condition have not been clearly defined in cancer patients. In this study, we aimed to investigate the association between sarcopenia and serum levels of myostatin, insulin-like growth factor-1 (IGF-1), and interleukin-6 (IL-6) in patients with newly diagnosed lung cancer. Material and Method: This cross-sectional prospective study included patients with newly diagnosed metastatic non-small cell lung cancer (NSCLC), who were categorized into two groups based on the presence or absence of sarcopenia. Body composition and muscle mass were evaluated using bioelectrical impedance analysis (BIA), and body mass index (BMI) was calculated. Handgrip strength was measured using a handheld dynamometer. Serum levels of myostatin, insulin-like growth factor-1 (IGF-1), and interleukin-6 (IL-6) were analyzed from fasting venous blood samples to assess their association with sarcopenia. Results: A total of 69 patients were included in the study. The patients' ages ranged from 49 to 75 years. Thirty-four of these patients were sarcopenic and thirty-five of them were non-sarcopenic. Eighty-seven percent (60) of the patients included in the study were male. While myostatin and IL-6 levels were higher in the sarcopenic patient group, IGF-1 mean levels were lower. In the non-sarcopenic patient group, the median levels of myostatin, IL-6, and IGF-1 were 11.82 ng/mL, 1.17 pg/mL and 23.51 ng/mL, respectively. In the sarcopenic patient group, the median levels of myostatin, IL-6, and IGF-1 were 16.76 ng/mL, 7.42 pg/mL and 12.82 ng/mL, respectively (p < 0.001, p < 0.01, and p < 0.001, respectively). Spearman's correlation analysis between SMI (skeletal muscle mass index) and myostatin, IGF-1 and IL-6 levels showed a negative correlation of SMI with myostatin and IL-6, and a positive correlation with IGF-1 [(r = -0.436, p < 0.001) (r = -0.520, p < 0.001), (r = 0.219, p:0.071) respectively]. When a logistic regression model was constructed with sarcopenia status as the dependent variable and myostatin, IGF-1, IL-6, and ECOG performance parameters as independent variables, myostatin and IGF-1 were identified as independent predictors [OR: 1.332, CI: (1.128-1.574), p: 0.001; OR: 0.926, CI: (0.874-0.982), p: 0.01, respectively]. Conclusion: We found a significant correlation between sarcopenia and myostatin, IGF-1 and IL-6 in patients with lung cancer. We suggest that myostatin, IGF-1, and potentially IL-6 may serve as reliable markers for sarcopenia in cancer patients. We believe that these findings may encourage future prospective studies investigating the potential relevance of myostatin, IGF-1 and IL-6 as markers of sarcopenia.