Clinicopathological characteristics and outcomes of gastric-type adenocarcinoma of the cervix: a systematic review.

Objective: We aimed to synthesize current evidence on the clinicopathological features, diagnostic strategies, treatment modalities, and outcomes of gastric-type adenocarcinoma (GAS) of the cervix, a rare and aggressive HPV-independent subtype of cervical adenocarcinoma. Methods: A systematic review was conducted in accordance with PRISMA 2020 guidelines and registered on PROSPERO. Comprehensive searches of PubMed, Scopus, ScienceDirect, and Springer were performed and supplemented by manual searches. Eligible studies were English-language case reports or case series describing histologically confirmed GAS, minimal deviation adenocarcinoma, or adenoma malignum. Data were extracted on clinicopathology, diagnostic modalities, treatments, and outcomes. Quality was appraised using the Joanna Briggs Institute checklists. Results: Fifty-nine studies were included, comprising 51 case reports and 8 case series, with a total of 150 patients. The mean age at diagnosis was 52.8 years, most commonly between 41 and 60 years. Vaginal bleeding and discharge were the leading initial symptoms, although over one-third lacked symptom data. Most cases were diagnosed at FIGO stage I-III, while 16% presented with stage IV disease. Radical hysterectomy was the predominant surgical approach, and concomitant chemoradiotherapy was the most frequent non-surgical treatment. IHC consistently demonstrated MUC6 and CK7 positivity, with frequent abnormal p53 and variable p16 expression. Recurrence occurred in 28.7% of patients, predominantly at distant sites, and 5-year survival was only 26.7%. Conclusion: GAS is a rare, distinct, and highly aggressive cervical adenocarcinoma with poor long-term outcomes and limited responsiveness to standard therapy. Improved diagnostic strategies and tailored treatment protocols are urgently needed.