Until now, the authors are aware of no major study that has suggested that neoadjuvant radiation had any distinct advantage over postoperative radiation in terms of survival for patients with resectable tumours.
In this retrospective analysis, study's senior author, Dr. David Sherr, assistant professor of clinical radiation oncology at Weill Cornell Medical College, and a radiation oncologist at NewYork-Presbyterian Hospital/Weill Cornell Medical Center, and colleagues analyzed data from 3,885 cases of resected pancreatic cancer, recorded between 1994 and 2003 as part of the national Surveillance, Epidemiology and End Results (SEER) registry database.
Of these cases, 2,337 (60 percent) of patients had received surgery alone, 1,478 (38 percent) received radiation after resection, and 70 (2 percent) received neoadjuvant radiation therapy.
The authors found that the overall survival of patients who received neoadjuvant radiation was 23 months, compared with 17 months for those receiving post-surgical radiotherapy and just 12 months for patients who received surgery alone.
Controlling for variables such as patient age, sex, cancer stage, grade and year of diagnosis, they found that neoadjuvant radiation cut the death risk for patients by 45 percent compared with other treatment strategies, and by 37 percent compared with radiation performed after surgery.
"It may be that in shrinking the tumour, pre-operative radiation gives the surgeon more of a margin of healthy tissue to work with. Because of that, patients are less likely to have microscopic residual disease," Dr. Sherr said.
He stressed that the findings do need to be verified by a randomised, prospective trial before any firm recommendations can be made. Dr. Sherr is hopeful that such a trial will be conducted in the future.
"In the meantime, this is really heartening news for patients. It suggests that there may be a real advantage to pre-operative radiation. Right now, when a pancreatic tumor is deemed operable, patients typically go straight to surgery. This suggests that - in some cases at least - we may be able to boost the odds of cure if we employ radiation first. More study is needed, but I believe this type of research has the potential to change practice," Dr. Sherr said.
The study is published in the Nov. 15 issue of the International Journal of Radiation Oncology, Biology and Physics.