Clinicopathological characteristics, diagnosis, treatment, and outcomes of primary gastric adenosquamous carcinoma

BACKGROUND Primary gastric adenosquamous carcinoma (ASC) is a rare subset of ASC. This study aims to investigate the clinicopathological features, diagnosis, treatment, and outcomes of primary gastric ASC. METHODS The medical records of 13 consecutive patients with primary gastric ASC between January 2010 and July 2014 from a single institutional database were reviewed. RESULTS Male predominance was observed (M/F = 10/3) among the patients, and their median age was 62 years (range: 43 to 79 years). The primary lesions were most often found in the upper third of the stomach, with a median tumor size of 5 cm (range: 2.25 cm to 10.5 cm). Ten patients underwent radical resections (R0 resection, 76.9%), while three patients had palliative resections (R1/R2 resection, 23.1%). Twelve patients had lymph node metastasis at the time of surgery. Adenocarcinoma and squamous cell carcinoma components in lymph node were found in eight and two cases, respectively, while two patients had both squamous cell carcinoma and adenocarcinoma components. In terms of the TNM staging system, stages IIB, IIIA, IIIB, IIIC, and IV were detected in 2 (15.4%), 2 (15.4%), 1 (7.7%), 5 (38.5%), and 3 (23.1%) patients, respectively. The median follow-up period was 22 months (range: 5 to 52 months); during which, four patients were still alive and eight patients died because of tumor progression. The 1-, 2-, and 3-year survival rates were 76.9%, 46.2%, and 15.4%, respectively. CONCLUSIONS Primary gastric ASC has a very poor prognosis, and both squamous cell carcinoma and adenocarcinoma components have distant metastasis potential.