Background: Gastric signet ring cell carcinoma (SRC) is a histological type based on microscopic characteristics and not on biological behavior. This study compared the clinicopathological features and prognosis of advanced SRC with non-signet ring cell adenocarcinoma (NSRC) of the stomach. Methods: We reviewed the records of 4,759 consecutive patients diagnosed with advanced gastric adenocarcinoma who were resected surgically from 1987 to 2003. Of these, 662 patients (13.9%) had SRC and were compared with 4,097 patients with NSRC. Results: Significant differences were noted in tumor size, Borrmann type, depth of invasion, lymph node metastasis, peritoneal dissemination and TNM stage. The cumulative 5-year survival rate for advanced SRC was 42.4%, compared with 50.1% in NSRC (p = 0.009). Multivariate analysis showed that tumor size ≧5 cm, Borrmann III and IV, T3–4 invasion and SRC histology were independent risk factors for lymph node metastasis. Depth of invasion, lymph node metastasis, hepatic and peritoneal metastasis and surgical curability were significant factors affecting survival. SRC histology alone was not an independent prognostic factor. Conclusions: Advanced gastric SRC tends toward deeper tumor invasion and more lymph node and peritoneal metastasis than NSRC. Advanced gastric SRC had a worse prognosis than NSRC. Therefore, curative surgical operation with extended lymph node dissection is recommended.

Recurrence of EGC after curative resection can be predicted by using common clinical characteristics. Patients at high risk of overall and early recurrence could be identified; individual disease-free survival was predictable by the internally validated nomogram.

Complete endoscopic resection may be acceptable as a curative treatment for intramucosal undifferentiated EGC when the tumor size is less than or equal to 2 cm, and when LVI is absent in the postoperative histological examination. Radical gastrectomy should be recommended if LVI or unexpected submucosal invasion is present.