Radiation important addition to pancreatic cancer surgery
Volume 5, Issue 2, 2016
Adding radiation treatment in combination with surgery and chemotherapy reduces the rate of cancer recurrence.
Christopher (Chris) L. Hallemeier, M.D.
A new study by Mayo Clinic researchers finds that radiation therapy is associated with a lower risk of cancer recurrence in pancreatic cancer surgery patients, making it, like chemotherapy, an important addition to surgery.
"Whether radiotherapy helps patients after pancreatic cancer surgery has been a long-standing question, and the findings suggest that it does," said Christopher (Chris) L. Hallemeier, M.D., a radiation oncologist with the Mayo Clinic Cancer Center, Rochester, Minnesota. The study was published in the March 1, 2016, issue of the American Society for Radiation Oncology's International Journal of Radiation Oncology, Biology, Physics.
Researchers studied 458 patients who had pancreatic cancer surgery at Mayo Clinic between March 1987 and January 2011. Of those patients, 378 received both chemotherapy and radiation therapy after surgery, and 80 had only chemotherapy after surgery.
Eighty percent of those who received both chemotherapy and radiation after surgery had no recurrence of cancer within the area targeted by the radiation therapy, within the tumor bed, and within the lymph nodes five years after diagnosis. That compared with 68 percent of those who had chemotherapy only after surgery. In addition, patients who received radiation therapy had longer survival times.
"Over the past five years or so, the trend has been toward providing chemotherapy and radiation before surgery in an increasing number of patients with operable pancreatic cancer," Dr. Hallemeier said. He and his colleagues plan research to study the benefit of pre-surgery chemotherapy and radiation, but first wanted to address the longtime question of whether radiation helps after surgery.
"The role of radiation therapy in operable pancreatic cancer has been somewhat controversial. There have been some studies that have shown a benefit and some studies that have not shown a benefit," Dr. Hallemeier said. "Our large study suggests that adding radiation treatment in combination with surgery and chemotherapy reduces the rate of cancer recurrence."
Pancreatic cancer is the fourth-leading cause of cancer death, and it is on the rise. About 50,000 people are diagnosed with pancreatic cancer each year in the U.S., and in about half, the cancer has spread elsewhere in the body, ruling out surgery. Historically, only about 7 percent of pancreatic cancer patients have lived at least five years after diagnosis.
About 15 percent of patients have cancer isolated within the pancreas, making them candidates for an operation to remove the tumor. In the remaining 35 percent, the cancer involves critical blood vessels outside the pancreas; in some cases, especially with chemotherapy and radiation before surgery, operations are complex but possible.
Asking the black-and-white question, "Surgery, yes or no?" has historically been the first approach. That's now being blurred.
"We're realizing that there are patients in the middle of the spectrum who may be candidates for surgery," Dr. Hallemeier said. "With tailored approaches to treatment before surgery, for example, using chemotherapy first to see how the tumor responds, and then selectively using radiation, I think we can personalize treatment for patients who are most likely to benefit."