Standard versus extended lymphadenectomy associated with pancreatoduodenectomy in the surgical treatment of adenocarcinoma of the head of the pancreas: a multicenter, prospective, randomized study. Lymphadenectomy Study Group

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.