Abstract
Rectal neuroendocrine tumours are rare but increasing worldwide. However, there is limited data from regions like the Indian subcontinent, where clinical presentations and outcomes may differ due to unique demographic and biological factors. This study aimed to characterize rectal neuroendocrine tumours in our region, focusing on clinic-pathological presentation, and treatment outcomes. This was an observational single-centre retrospective cohort study from a high-volume tertiary care centre in Western India. Sixty-five consecutive patients with rectal neuroendocrine tumours treated between 2013 and 2023 were included. The main outcome measures were overall survival and disease-free survival. Secondarily, we tried to evaluate the impact of pathological grade and surgery-type on survival outcomes. The median age at diagnosis was 50 years, younger than the global median (56-57 years), with a male predominance (80%). Majority of patients were symptomatic and had locally advanced disease, with 64% showing metastatic spread. Pathologically, 82% of tumours were classified as Grade II/III, with a high median tumour size (3.7 cm) and elevated serum Chromogranin A levels. Multimodal treatment, including surgery and adjuvant therapies, was utilized for most patients. Of the 41.5% who underwent surgery, 70% had sphincter-preserving procedures. The median overall survival for the entire cohort was not reached, but 3-year and 5-year overall survival rates were 91% and 85%, respectively. Grade III tumours had significantly poorer outcomes, with a 5-year survival of 57% compared to nearly 100% in Grade I and II tumours. Apart from its retrospective nature, our study may have limited generalizability due to potential referral bias, and the lack of detailed pathological subclassification would be an opportunity for future research. As the first study from the Indian subcontinent we highlight how our patients presented at a younger age with advanced, aggressive disease. Multimodal approach could improve outcomes even in advanced disease.