Outcomes of Patients With Appendiceal Neoplasms Based on Clinicopathological Features and Surgical Intervention: A Retrospective Observational Study at a Tertiary Cancer Centre in India.

Introduction Tumour biology remains the key determinant of prognosis in appendiceal neoplasms. In this study, we analyse the clinicopathological characteristics and outcomes of patients with appendiceal neoplasms treated at our institution, with particular emphasis on overall survival among different tumour types. Material and methods Patients with histologically confirmed appendiceal neoplasms treated between January 2021 and December 2025 were included. Clinical, pathological, treatment, and follow-up data were retrieved from medical records and institutional databases. Variables analysed included age, gender, histological subtype, disease stage, treatment modality, recurrence status, and survival outcomes. The primary endpoint was overall survival (OS) among treated appendiceal neoplasms with different tumor subtypes. A subgroup analysis was also performed to study the difference in treatment outcomes in patients with low-grade appendiceal mucinous neoplasm (LAMN) and their overall survival. Results Among the 55 patients in our study, the following observations were made. The median age of patients at presentation was 54 years [95% confidence interval (CI): 46-61], with a slight female predominance, 30(54.5%). The majority of patients, 37 (67.3%), had LAMN, followed by eight (14.5%) with high-grade appendiceal mucinous neoplasm (HAMN), eight (14.5%) with adenocarcinoma, and two (3.6%) with signet ring adenocarcinoma. Many patients presented with advanced disease, with stage IV accounting for 53.7% of cases (22 out of 41 patients had stage 4 disease). Overall survival differed significantly by histopathology. Patients with LAMN histology had better survival compared with other histologic subtypes (log-rank p = 0.026). In Cox proportional hazards analysis, LAMN was also associated with a lower risk of death [hazard ratio (HR) = 0.24, p = 0.040]. Among patients with LAMN histology, overall survival did not differ significantly between those undergoing appendectomy alone and those undergoing other surgical procedures (log-rank p = 0.48). Both groups demonstrated high survival rates (> 85%) up to three years, with very few deaths observed. Conclusion Our findings demonstrate that survival in treated appendiceal neoplasms is predominantly influenced by tumour biology, particularly histological risk group and metastatic status at presentation. Patients with low-grade mucinous neoplasms experienced relatively favourable outcomes, often surviving without recurrence, whereas high-risk histology variants were associated with poorer survival and increased incidence of peritoneal dissemination.