Evaluation of preoperative sarcopenia and postoperative results in non-small cell lung cancer

Sarcopenia is a syndrome characterized by widespread and progressive loss of muscle mass and muscle strength, which reduces the quality of life and may even cause death. Many known factors play a significant role in the etiology of sarcopenia. A malignancy is one of the most well-known factors predisposing to the development of sarcopenia. Sarcopenia presence has been proven in many studies as an independent risk factor for mortality and has also been associated with a higher risk of postoperative complications. This study aims to investigate the effect of sarcopenia on postoperative complications and survival in patients who were operated for lung cancer. Patients who were operated for the diagnosed NSCLC between January 2012 and December 2022 at Ankara University Faculty of Medicine (AÜTF) Department of Thoracic Surgery were scanned retrospectively. Patients who had no radiological images available, who had a previous thoracotomy history, who had received neoadjuvant treatment, or who had a previous diagnosis of any other malignancy were excluded from the study. Within those inclusion and exclusion criteria; 293 patients were included in the study. The demographic characteristics, comorbidities, respiratory function values, ASA scores, surgical approaches, resection types, postoperative data and survival status of the patients were analyzed. The psoas muscle indexes of the patients were calculated by using the body mass indexes at hospital admission and the psoas muscle areas at the level of the 3rd lumbar (L3) vertebra of the preoperative PET/CT images. Sarcopenia was diagnosed using threshold values of 6.36 cm2/m2 for men and 3.92 cm2/m2 for women. Complications observed in the postoperative period were graded by using modified Clavien-Dindo. Overall survival is the time from the date of operation to the date of patient death for any reason; Recurrence-free (disease-free) survival was defined as the time from the date of surgery until the date of recurrence or the patient's last follow-up date. Of the patients included in the study, 223 (76%) were men and 70 (24%) were women. The median age was 62. Sarcopenia was detected in 199 of 293 (68%) patients in the study, and sarcopenia was not detected in 94 (32%) patients. It was found that the male gender ratio was higher (81.4%), the median age value was higher (p=0.003) and their body mass index (BMI) was lower (p<0.001) in sarcopenic patients. No difference was detected between the groups in terms of performance status, comorbidities, respiratory function capacities and lung resection performed. The sarcopenic patient group consisted of patients diagnosed at a more advanced stage (p=0.023) and with a higher rate of adenocarcinoma (p=0.022). When postoperative data were compared, the frequency of pneumonia (0.03) and prolonged air leakage rates (0.025) were higher in sarcopenic patients. There was no difference between the groups in terms of the degree of complications and length of stay in the intensive care unit (p=057, p=0.06). Five-year overall survival rates were worse in sarcopenic patients (p=0.003). In univariate and multivariate analyses, it was found that the male gender, the presence of COPD, the stage of the disease, the degree of postoperative complications and the sarcopenia presence affect 5-year overall survival rates. As a result, studies have shown that sarcopenia has an impact on postoperative complications, relapse-free survival and overall survival. For sarcopenia, which can be easily diagnosed in routine radiological examinations in the preoperative period and has no short-term treatment; a solution can be found by making accurate risk scoring in the preoperative preparation, taking precautions against expected postoperative complications and close follow-up. To improve surgical results, increase the quality of life and prolong patients' survival, it is necessary to inform patients with sarcopenia preoperatively, develop preventive measures and rehabilitation programs, provide both immune and conventional nutritional support in the preoperative and postoperative periods, and create sarcopenia-specific strategies when planning surgical interventions.