Histomorphological Spectrum of Low-Grade Appendiceal Mucinous Neoplasm: A Case Series of Seven Cases at a Tertiary Care Hospital in India
DOI:
https://doi.org/10.21276/apalm.3951Keywords:
LAMN, appendiceal mucinous neoplasm, appendiceal mucocele, pseudomyxoma peritoneiAbstract
Introduction: Low-grade appendiceal mucinous neoplasm (LAMN) represents an uncommon epithelial tumor of the appendix characterized by mucin-producing epithelium with low-grade cytological atypia and an expansile pattern of growth. Despite its indolent and almost benign histological appearance, it possesses the potential for significant morbidity owing to complications such as pseudomyxoma peritonei particularly following appendiceal rupture and dissemination of mucinous material into the peritoneal cavity.
Case Presentation: A retrospective analysis of seven histologically confirmed cases of LAMN was performed. Clinical data, radiological findings, operative details, and pathological features were retrieved from institutional records and systematically analyzed.
Conclusion: The patient cohort ranged from 25 to 80 years, with a mean age of approximately 51 years and a slight male predominance. The predominant clinical presentation was right iliac fossa pain, frequently mimicking acute appendicitis. Radiological imaging commonly demonstrated cystic dilatation of the appendix consistent with appendiceal mucocele. Gross examination revealed distended appendices with mucin-filled lumina. Histologically, lesions exhibited mucinous columnar epithelium with low-grade atypia, nuclear stratification, mural fibrosis, and extracellular mucin dissecting the appendiceal wall; all common histological features of LAMN. One case demonstrated xanthogranulomatous inflammation, while another showed perforation with mucin extravasation.
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