Abstract / Summary
Appendiceal epithelial neoplasms are uncommon lesions, often detected incidentally on histopathological examination of appendicectomy or resection specimens. They comprise a heterogeneous group of tumours ranging from mucinous neoplasms to invasive adenocarcinomas, with varied morphology, biological behaviour, and clinical outcome. Their relative rarity and overlapping clinical presentation make histopathological evaluation essential for accurate diagnosis and classification. The present case series describes the clinical and histomorphological features of seven cases of epithelial appendiceal neoplasms diagnosed at a tertiary care centre. The cases included four adenocarcinomas- one goblet cell adenocarcinoma, two mucinous adenocarcinomas, and one non-mucinous adenocarcinoma- along with two Low-grade Appendiceal Mucinous Neoplasms (LAMN) and one High-grade Appendiceal Mucinous Neoplasm (HAMN). The median age at presentation was 64 years. There was a female predominance, with six females and one male. Histologically, the lesions showed varied architectural patterns, cytological atypia, mucin production, and differing extent of appendiceal wall involvement. One case was associated with pseudomyxoma peritonei, while another showed synchronous adenocarcinoma of the ascending colon. Serum Carcinoembryonic Antigen (CEA) was elevated in most evaluated cases, whereas Cancer Antigen 125 (CA-125), was elevated in one case. Classification was based on the World Health Organisation (WHO) 5th edition classification, and staging was assessed using the American Joint Committee on Cancer (AJCC) staging system. Follow-up ranged from six months to two years. During the follow-up period, four patients remained disease-free, while one patient demonstrated stable disease while receiving chemotherapy. One patient died due to disease progression, and follow-up information was unavailable for one patient. This series is important as it highlights the rarity and clinicopathological diversity of appendiceal epithelial neoplasms encountered in routine surgical pathology practice. The lesions ranged from low-grade mucinous neoplasms to invasive adenocarcinomas with distinct biological behaviour and differing prognostic implications, including variation in risk of recurrence, progression, and development of Pseudomyxoma Peritonei (PMP). Recognition of these morphological differences is essential for accurate pathological subtyping, as it directly influences staging, prognostic assessment, therapeutic planning, extent of surgical management, postoperative surveillance, and long-term follow-up.