Prognosis of pN3 stage gastric cancer

Abstract

[한글]

[영문]

The aim of this study was to determine the prognosis and the recurrence pattern of pN3 stage gastric cancer patients after the curative resection, and to identify the prognostic factors according to the clinico-pathologic features. Between January 2000 and December 2004, I retrospectively reviewed the medical records of the patients as histological confirmed pN3 stage of gastric cancer without distant metastasis including peritoneal seeding, hepatic metastasis or para-aortic lymph node metastasis. They underwent both gastrectomy and D2 or D3 lymphadenectomy with a curative aim. I then analyzed the survival according to clinico-pathologic factors as age, sex, tumor location, the type of gastrectomy, the gross features of the tumor, tumor size, tumor differentiation, and the depth of invasion, Lauren classification, lymphatic invasion, vascular invasion, the number of dissected and metastatic lymph nodes and the proportion of metastatic lymph nodes to dissected lymph nodes, the node stage by the Japanese Classification of Gastric Cancer, involvement of perigastric lymph nodes which subdivided by Group 1 vs. others, and adjuvant chemotherapy. And I also examined recurrence pattern in pN3 gastric cancer patients.Out of 467 patients with stage IV gastric adenocarcinoma who received surgery, 260 patients underwent curative resection and they were pathologically staged as N3. Among these 260 patients, 179 patients were pN3 stage gastric cancer without distant metastasis. The median age was 62 years (range: 16-82 years). The most common site of gastric cancer was lower third of the stomach (48.6%). Among 179 patients, 84 patients (46.9%) were restaged as N2 stage and 18 patients (10.1%) were restaged as N1 stage by JCGC. The majority of patients were received adjuvant chemotherapy (75.4%). Among 179 patients, 123 patients (68.6%) had recurred and the majority of recurrent site of gastric cancer was peritoneal metastasis (30.9%). The 3-year and 5-year disease free survival rate were 16.2% and 9.5%, respectively. The median time to recurrence was 11.9 months (range: 0.5-108.2 months).For all the patients, the median follow-up period was 19.6 months (range: 0.5-108.2 months) and the median overall survival time was 19.6 months (95% CI, 15.17 ? 23.96). The 3-year and 5-year survival rate of the pN3 gastric cancer patients were 27.9% and 12.8%, respectively. The identified predictors for a worse prognosis were Borrmann type III and IV group (HR: 1.79, 95% CI, 1.12 ? 2.86, p = 0.020), the group without adjuvant chemotherapy (HR: 6.23, 95% CI, 3.08 ? 12.62, P < 0.0001), the number of dissected lymph nodes more than 65 (HR: 2.06, 95% CI, 1.31 ? 3.26, p = 0.002) and the ratio of metastatic lymph nodes between 66 and 100 (HR: 2.01, 95% CI, 1.15-3.53, p = 0.015) for the pN3 patients. I suggested that gastric cancer patients staged as pN3 only without distant metastasis had a different prognosis by clinico-pathologic features, especially by metastatic lymph node ratio and adjuvant chemotherapy. These pN3 gastric cancer patients needed aggressive adjuvant chemotherapy after curative gastrectomy for better prognosis.