Objective: The study was conducted to determine whether the performance of an extended lymphadenectomy and retroperitoneal soft-tissue clearance in association with a pancreatoduodenal resection improves the long-term survival of patients with a potentially curable adenocarcinoma of the head of the pancreas.
Summary background data: The usefulness of performing an extended lymphadenectomy and retroperitoneal soft-tissue clearance in conjunction with a pancreatoduodenal resection in the treatment of ductal adenocarcinoma of the head of the pancreas is still unknown. Published studies suggest a benefit for the procedure in terms of better long-term survival rates; however, these studies were retrospective or did not prospectively evaluate large series of patients.
Materials and methods: Eighty-one patients undergoing a pancreatoduodenal resection for a potentially curable ductal adenocarcinoma of the head of the pancreas were randomized to a standard (n = 40) or extended (n = 41) lymphadenectomy and retroperitoneal soft-tissue clearance in a prospective, multicentric study. The standard lymphadenectomy included removal of the anterior and posterior pancreatoduodenal, pyloric, and biliary duct, superior and inferior pancreatic head, and body lymph node stations. In addition to the above, the extended lymphadenectomy included removal of lymph nodes from the hepatic hilum and along the aorta from the diaphragmatic hiatus to the inferior mesenteric artery and laterally to both renal hila, with circumferential clearance of the origin of the celiac trunk and superior mesenteric artery. Patients did not receive any postoperative adjuvant therapy.
Results: Demographic (age, gender) and histopathologic (tumor size, stage, differentiation, oncologic clearance) characteristics were similar in the two patient groups. Performance of the extended lymphadenectomy added time to the procedure, although the difference did not reach statistical significance (397 +/- 50 minutes vs. 372 +/- 50 minutes, p > 0.05). Transfusion requirements, postoperative morbidity and mortality rates, and overall survival did not differ between the two groups. When subgroups of patients were analyzed, using an a posteriori analysis that was not planned at the time of study design, there was a significantly (p < 0.05) longer survival rate in node positive patients after an extended rather than a standard lymphadenectomy. The survival curve of node positive patients after an extended lymphadenectomy could be superimposed onto the curves of node negative patients. Survival curves in node negative patients did not differ according to the magnitude of the lymphadenectomy. Multivariate analysis of all patients showed that long-term survival was affected by tumor differentiation (well vs. moderately vs. poorly differentiated, p > 0.001), diameter (< or = 2.0 cm. vs. > 2.0 cm., p < 0.01), lymph node metastasis (absent vs. present, p < 0.01) and need for 4 or more units of transfused blood (< 4 vs. > or = 4, p <0.01).
Conclusions: The addition of an extended lymphadenectomy and retroperitoneal soft-tissue clearance to a pancreatoduodenal resection does not significantly increase morbidity and mortality rates. Although the overall survival rate does not differ in the two groups, there appears to be a trend toward longer survival in node positive patients treated with an extended rather than a standard lymphadenectomy.