Resectable gastric signet ring cell carcinoma: clinicopathological characteristics and survival outcomes

Background: Gastric signet ring cell carcinoma (SRCC) appears to have clinical features and survival rates particularly different from other histological types. The aim of this study was to investigate clinicopathological features and survival outcomes of SRCC and to compare them with non-signet ring cell carcinoma (NSRCC). Methods: We retrospectively studied 145 patients with non-metastatic gastric carcinoma who underwent gastrectomy in our institute from 2005 to 2015. Among them, 36 patients (9.4%) with SRCC were compared to 109 patients (90.6%) with NSRCC. Results: Patients with SRCC presented at a younger age (p=0.001) with more advanced stage III-IV disease (p=0.005) and advanced N stages with a higher rate of pN3 (p=0.0001), a higher number of invaded lymph nodes (p=0.002) and a higher rate of patients with a lymph node ratio exceeding 25% (63.9% vs 36.7, p=0.004). After a median follow up of 35.30 months, there was no significant difference in the 5 years overall (OS) survival between SRCC and NSRCC ((36.7% vs 45.7%, p=0.206).However, the 5 years progressive free survival (PFS) was significantly decreased in case of SRCC (38.7% vs 50.9%, p=0.038) with a higher rate of metastasis in (52.9% vs 29.5%, p=0.013) and peritoneal recurrence (35.3% vs 9.5%, p<0.0001). The main prognostic factors of PFS and OS in SRCC were tumoral stenosis, hypoprotidemia, tumor size, depth of invasion (p=0.001), perineural and lymphovascular invasion, the UICC stage and complete surgical resection. Conclusion: Gastric SRCC have a particular clinicopathological behavior compared to NSRCC suggesting its more aggressive character.