Induction chemotherapy selects patients with locally advanced, unresectable pancreatic cancer for optimal benefit from consolidative chemoradiation therapy

BACKGROUND. The current study was conducted to determine whether there were differences in outcome for patients with unresectable locally advanced pancreatic cancer (LAPC) who received treatment with chemoradiation therapy (CR) versus induction chemotherapy followed by CR (CCR). METHODS. Between December 1.993 and July 2005, 323 consecutive patients with LAPC were treated at the authors' institution with radiotherapy and concurrent gemcitabine or fluoropyrimidine chemotherapy. Two hundred forty-seven patients received CR as initial treatment, and 76 patients received a median of 2.5 months of gemcitabine-based induction chemotherapy prior to CR. Most patients received a radiation dose of 30 grays in 10 fractions (85%) concurrently with infusional 5-fluorouracil (41%), gemcitabine (39%), or capecitabine (20%). RESULTS. The median follow-up was 5.5 months (range, 1-63 months). For all patients, the median overall survival (OS) and progression- free survival (PFS) were 9 months and 5 months, respectively, and the 2-year estimated OS and PFS rates were 9% and 5%, respectively. The median OS and PFS were 8.5 months and 4.2 months, respectively, in the CR group and 11.9 months and 6.4 months, respectively, in the CCR group (both P <.001). The median times to local and distant progression were 6.0 months and 5.6 months, respectively, in the CR group and 8.9 and 9.5 months, respectively, in the CCR group (P =.003 and P =.007, respectively). There was no significant difference in the patterns of failure with the use of induction chemotherapy. CONCLUSIONS. The results from this analysis indicated that, by excluding patients with rapid distant progression, induction chemotherapy may select patients with LAPC for optimal benefit from consolidative CR. The authors believe that this strategy of enriching the population of patients who receive a locoregional treatment modality merits prospective randomized evaluation.