Survival analysis of linitis plastica advanced gastric cancer patients receiving S-1 plus cisplatin.

Abstract

e15105 Background: Linitis plastica gastric cancer (LPGC) has been known to have worse prognosis than non-LPGC. Clinical trial using molecular targeting agent has been ongoing for LPGC. However it remains unknown whether to be better to change the chemotherapy for the patients. S-1 plus cisplatin (SP) is the standard chemotherapy for previously untreated Japanese advanced gastric cancer (AGC). Methods: To clarify the clinical feature and outcome of LPGC treated with chemotherapy, we retrospectively compared the patients with unresectable or metastatic LPGC and non-LPGC who received SP as the first-line chemotherapy in Cancer Institute Hospital of JFCR between 2007 and 2011. Results: In the period there were 687 patients with AGC who received systemic chemotherapy and 223 (LPGC 63 and non- LPGC 160) patients received SP as first-line chemotherapy. LPGC patients were more frequent in female (44.0% vs. 26.9%; P=0.016). LPGC was more likely to have non-measurable disease (39.7% vs. 14.4%; P<0.001), peritoneal metastasis (73% vs. 35.6% P<0.001), and diffuse type histology (diffuse type 85.7% vs. 56.3%, intestinal type 7.9% vs. 27.5%; P<0.001). LPGC was less likely to have liver metastasis (7.9% vs. 27.5%; P<0.001), and no evaluable distant metastasis in computed tomography (81.0% vs. 93.8%; P=0.010). Other clinicopathological characteristics were follows (LPGC patients vs. non-LPGC patients): median age (57 vs. 62 years), disease status (recurrent 11.1% vs. 18.8%), ECOG PS 0 (81.0% vs. 81.9%), number of metastatic sites (1: 52.4% vs. 46.9, 2: 39.7% vs. 46.9%, ³a3: 7.9% vs. 6.2%), lymph node metastasis (63.5% vs. 70.6%), prior gastrectomy (31.7% vs. 35.6%). They were not significantly different. Median overall survival time is 383 days (95% CI 332-564) in LPGC patients and 473 days (95% CI 412-555) in non-LPGC patients (P=0.363). Median time to treatment failure is 229 days (95% CI 155 - 280) in LPGC patients and 189 days (95% CI 156 -219) in non-LPGC patients (P=0.245). Conclusions: Although clinicopathological backgrounds were not identical, it was suggested that the prognosis of the patients treated with SP was not different between advanced or metastatic LPGC and non-LPGC.