ORLANDOOverall survival after pancreatic resection can be markedly improved with adjuvant chemoradiation therapy, according to investigative groups who presented encouraging data on two different regimens at the 2008 Gastrointestinal Cancers Symposium.
Survival after pancreaticoduodenectomy for pancreatic adenocarcinoma is only about 10% to 25% at 5 years, and the value of adjuvant chemoradiation therapy has been inconsistent in clinical trials. Results from a large cooperative study from Johns Hopkins and the Mayo Clinic (abstract 124), and from a smaller study of a novel regimen (abstract 125), suggest that adjuvant chemoradiation is beneficial rather than harmful, as a prior study suggested, possibly signaling an end to the controversy.
Charles C. Hsu, PhD, of Johns Hopkins Hospital, said, "At two high-volume centers for the treatment of pancreatic cancer, adjuvant chemoradiation therapy, compared to surgery alone, improved survival by 35% overall and consistently decreased risk by 17% to 43% among all subgroups. We also found that the status of resection should not significantly alter adjuvant chemoradiation therapy recommendations."
Dr. Hsu presented the results of a study of 1,092 patients treated with an adjuvant fluorouracil (5-FU)-based regimen plus radiotherapy at a mean dose of 50.4 Gy (n = 583) or by resection with curative intent only (n = 509).
Slightly more patients in the observation-only arm had negative surgical margins (R0) as well as low-grade histology. A propensity score analysis was conducted to account for biases associated with these differences. [Editor's note: See page 31 for a study of adjuvant chemoradiation in only R0 patients at Mayo.]
Dr. Hsu noted that the strengths of this study were its attempt to account for the nonrandom allocation and the fact that the data came from high-volume pancreatic cancer centers.
Odds of dying reduced 26%
Adjuvant chemoradiation significantly reduced the odds of dying by 26%, compared with surgery only, Dr. Hsu reported. Median overall survival in the observation arm was 15.5 months, increasing to 21.1 months with adjuvant chemoradiation therapy. Two-year survival was 34.6% vs 44.7%, respectively, and 5-year survival was 16.1% vs 22.3% (P < .001).