Analysis of clinicopathological characteristics and prognosis on primary gastric adenosquamous carcinoma

Primary gastric adenosquamous carcinoma (PGASC) is a rare type of gastric cancer with limited research and poorly understood clinicopathological features. This study investigated the clinicopathological features and outcomes of PGASC. Patients with PGASC from Union Hospital, Tongji Medical College, Huazhong University of Science and Technology and from the published literature were enrolled in this study. Survival curves were generated using the Kaplan-Meier method, and prognostic factors were identified through Cox proportional hazards regression models. This study identified 76 eligible cases of PGASC, with 45 cases from published literature and 31 from our center. The most prevalent symptoms were abdominal pain and dysphagia, with a median age of 62 years (range: 29-84 years). The primary lesions were predominantly in the proximal stomach, with a median tumor size of 6.5 cm (range: 1.5-16.0 cm). Tumor stages II, III, and IV were detected in 12 (16.7%), 43 (59.7%), and 17 (23.6%) patients, respectively. Most tumors were poorly differentiated in both the squamous cell carcinoma (SCC) component and adenocarcinoma (AC) component. The median survival time was 17 months (range: 2-122 months). The 1, 3, and 5-year overall survival (OS) was 60.7%, 31.1%, and 24.1%, respectively. Multivariate analysis revealed that OS was independently predicted by the proportion of SCC component, differentiation of AC component, and tumor stage. PGASC is a rare disease with a poor prognosis. A high proportion of SCC components, low differentiated AC components, and advanced tumor were associated with worse survival in patients with PGASC. Adjuvant therapy did not improve survival time.