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What is A subtotal gastrectomy with D2 dissection performed for Stage 3 gastric adenocarcinoma in the antrum includes ? and explain in detail?
The standard operation for gastric cancer is radical subtotal gastrectomy, which entails ligation of the left and right gastric and gastro-epiploic aeries at the origin, as well as the en bloc removal of the distal 75% of the stomach, including the pylorus and 2 cm of duodenum, the greater and lesser omentum, and all associated lymphatic tissue. Generally, the surgeon strives for a grossly negative margin of at least 5 cm. In the absence of involvement by direct extension, the spleen and pancreatic tail are not removed. The operation is deemed an adequate cancer operation provided that tumour- free margins are obtained, >15 lymph nodes are removed, and all gross tumour is resected. Reconstruction is usually by Billroth I gastro-jejunostomy or Roux-en-Y reconstruction.