[Clinico-pathological studies and problems on para-aortic lymph node dissection--D4 dissection]

The advantage or disadvantage of para-aortic lymph node dissection was studied from the viewpoint of clinicopathological findings and their prognosis. No 16 lymph node dissection was performed in 427 cases, and metastasis was observed in 100 (23%). The metastatic rate increased with the depth of cancer. High metastatic rates were seen in type 3 and 4, and in the histologically undifferentiated type. Five year survival rate of patients with No. 16 metastasis (PoHo) was 14%. The n3 (-) group among cases with n4 showed a significantly better outcome than the n3 (+) group. Concerning total gastrectomy with pancreato-splenectomy procedure, blood loss was greater and length of surgery was longer in the D4 group than D2 group. The exudate volume was much higher in D4 and serum albumin significantly decreased in D4 than D2. Almost the same findings were seen in D4 with subtotal gastrectomy. Postoperative complications in D4 group were the same as D2 excluding abscess around pancreatic stump which was higher in D4. In conclusion, D4 dissection does not have an obvious disadvantage for the patients. Randomized clinical trials between D4 and D2 should be done in order to clarify an efficacy of the D4 dissection.