The prognosis of patients operated on for gastric cancer in relation to the percentage of lymph nodes invaded by tumour.

Introduction: In evaluating the type of gastrectomy and lymphadenectomy for gastric cancer, adequate prognosis has been dependant on the retrieval of at least 15 lymph nodes. We propose an alternative method in which the prognostic value is evaluated, according to whether or not more than 20% of the retrieved lymph nodes are invaded by tumour.

Materials & Methods: Sixty-five patients (36 men, 29 women) with a median age of 69 years (mean age 68.9 +/-12.1 years) were evaluated, who were operated upon between 1985 and 1999 for gastric cancer by gastrectomy with either D1 or D2 lymphadenectomy.

Results: The average number of retrieved lymph nodes was 10.4 +/- 8.6. In 51 patients (78.5%) less than 15 and in 14 patients (21.5%) 15 or more lymph nodes were retrieved, according to the TNM guidelines. In our study, there is a statistically significant difference in prognosis between patients with less than 20% and those with more than 20% of the retrieved lymph nodes invaded by tumour, irrespective of the total number of lymph nodes resected.

Conclusion: Gastric cancer patients in whom less than 20% of the retrieved lymph nodes are invaded, have a significantly better prognosis compared with patients in whom 20% or more of the lymph nodes retrieved are invaded by tumour, irrespective of the total number of retrieved lymph nodes.