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Impact of preoperative therapy on patterns of recurrence in pancreatic cancer.

BACKGROUND
A theoretical advantage of preoperative therapy in pancreatic adenocarcinoma is that it facilitates the early treatment of micrometastases and reduces postoperative systemic recurrence.


METHODS
Medical records of 309 consecutive patients undergoing resection of adenocarcinoma in the head of the pancreas were reviewed. Survival was calculated using the Kaplan-Meier method. Associations between preoperative therapy and patterns of recurrence were determined using chi-squared analysis.


RESULTS
Preoperative therapy was administered to 108 patients and upfront surgery was performed in 201 patients. Preoperative therapy was associated with a significantly longer median disease-free survival of 14 months compared with 12 months in patients submitted to upfront surgery (P = 0.035). The rate of local disease as a component of first site of recurrence was significantly lower with preoperative therapy (11.3%) than with upfront surgery (22.9%) (P = 0.016). Preoperative therapy was associated with a lower rate of hepatic metastasis (21.7%) than upfront surgery (34.3%) (P = 0.026). Preoperative therapy did not affect rates of peritoneal or pulmonary metastasis.


CONCLUSIONS
Preoperative therapy for pancreatic cancer was associated with longer disease-free survival and lower rates of local and hepatic recurrences. These data support the use of preoperative therapy to reduce systemic and local failures after resection.