The impact of total retrieved lymph nodes on staging and survival of patients with pT3 gastric cancer.

Background: The incidence of lymph node metastasis is high in patients who have pT3 gastric cancer. However, the impact of total retrieved lymph nodes (tLNs) on staging and survival of these patients is not clear.

Methods: For this study, the authors examined 1895 patients with pT3 gastric cancer who underwent surgery at Yonsei University Medical College from January 1987 to June 2000.

Results: Four hundred sixty of 1895 patients (24.3%) were diagnosed with pT3N0 gastric cancer. Patients who had < 31 tLNs (25th percentile) had less advanced lymph node (N) stage than the other patients (P < .001). Lymph node metastasis had a positive association with the number of tLNs in a logistic regression analysis (P < .001; hazards ratio, 1.014; 95% confidence interval, 1.006-1.021). With a median follow-up of 61.1 months, the overall 10-year survival rate (10-YSR) was 42.8%. Patients with pT3N0 disease who had < 31 tLNs had a 10-YSR of only 55.4%. Although this 10-YSR did not differ significantly from the rate for patients with N0 disease who had > or =31 tLNs (65.8%; P = .108), it approached the rate for the N1 group (53.3%; P = .207). In multivariable analyses, the number of tLNs emerged as an independent prognostic predictor in patients with pT3N2 and pT3N3 disease, but not in patients with pT3N0 or pT3N1 disease.

Conclusions: Increasing numbers of tLNs may improve the accuracy of staging in patients who have pT3 gastric cancer. Because preoperative lymph node staging is difficult, a thorough lymph node dissection is mandatory in all serosa-positive patients.