Histological Spectrum and Classification of Gastric and Gastro-Oesophageal Junction Cancers in South-East Nigeria: A Retrospective Study

Background: Gastric and gastro-oesophageal junction cancers encompass a heterogeneous group of malignancies with distinct histological and biological characteristics. Histological classification remains central to diagnosis, prognostication, and therapeutic decision-making, particularly in settings where molecular profiling is not routinely available. Objective: This study examined the histological spectrum and classification patterns of gastric and gastro-oesophageal junction cancers diagnosed over a ten-year period in Anambra State, South-East Nigeria. Methods: A retrospective review was conducted of gastric and gastro-oesophageal junction cancer cases diagnosed between January 2011 and December 2020 across four major histopathology laboratories in Anambra State. Archived haematoxylin and eosin–stained slides and paraffin blocks were reviewed. Tumours were classified according to the 2019 World Health Organization classification of gastric tumours, with carcinomas further categorised using the Lauren classification system. Descriptive statistics and chi-square testing were applied, with statistical significance set at p < 0.05. Results: Ninety-three cases met inclusion criteria. Carcinomas constituted the majority of tumours, followed by mesenchymal tumours, lymphomas, and neuroendocrine tumours. Tubular adenocarcinoma was the most frequent carcinoma subtype, while intestinal-type carcinoma predominated under the Lauren classification. Most graded carcinomas were well differentiated. No statistically significant associations were identified between histological subtype and patient age or sex. Conclusion: Gastric and gastro-oesophageal junction cancers in this setting are dominated by epithelial malignancies, particularly tubular and intestinal-type adenocarcinomas. The observed histological profile aligns with patterns reported across Nigeria and other low- and middle-income settings, underscoring the continuing relevance of morphology-based classification in regional cancer practice.