Prevalence of Sarcopenia and Impact on Survival in Patients with Metastatic Gastroenteropancreatic Neuroendocrine Tumours

Simple Summary Neuroendocrine tumours are rare tumours arising in the digestive system, mainly the small bowel or pancreas. Due to their location in the digestive tract, NETs can cause symptoms of diarrhoea, abdominal pain or weight loss. These symptoms are often correlated with nutrition. Poor nutrition or malnutrition is well described. Sarcopenia is the loss of muscle mass or strength and a phenotype of malnutrition. In patients with cancer and sarcopenia, survival is poorer compared to patients without sarcopenia. There is little knowledge regarding sarcopenia and its effect on survival in patients with NETs. This study aims to describe the presence of sarcopenia at diagnosis of stage IV NET in the digestive system and correlate this with survival. Sarcopenia was present in 69% of patients. When there was a NET in the pancreas, the presence of sarcopenia was correlated with poorer survival. Sarcopenia in patients with cancer is associated with adverse outcomes such as shorter survival. However, there exists little evidence regarding the prevalence of sarcopenia in patients with metastatic gastroenteropancreatic neuroendocrine tumours (GEP-NETs). Patients with a histologically confirmed newly diagnosed metastatic GEP-NET between 2006 and 2018, CT scan, and anthropometric data at diagnosis were included in this study. CT scans were analysed for the presence of sarcopenia and correlated with overall survival (OS). In total, 183 patients, 87 male (48%), with a median age of 62 years (IQR 52-68 years), were included. In 44 patients (24%), there was a pancreas NET, and in 136 patients, there was a small bowel NET (74%). Sarcopenia was present in 128 patients (69%) and unrelated to BMI (median 25.1). There were significant survival differences between patients with pancreatic and small bowel NETs at 86 vs. 141 months, respectively (p = 0.04). For patients with pancreatic NETs, the presence of sarcopenia was independently associated with shorter OS (HR 3.79 95% CI 1.1-13.03, p-value 0.035). A high prevalence of sarcopenia at the time of diagnosis of a metastatic GEP-NET was seen and associated with worse OS in patients with pancreatic NETs. Further research should focus on how to reverse sarcopenia and its impact on OS and/or quality of life.