Patients with metastatic cancer tumors in their lungs are much more likely to live disease-free if they have an experimental treatment involving shaped-beam radiosurgery rather that conventional treatment, according to a University of Rochester Medical Center study.
The research, presented this week at the American Society of Therapeutic Radiology and Oncology conference in Philadelphia, offers a new option for the tens of thousands of patients annually who must cope with cancer that has spread to their lungs. Usually when the disease advances to that stage, the average survival time is 12 months and treatments are limited. In this study, some patients who were treated more than three years ago still have not had the disease spread.
Shaped-beam, radiosurgery technology was originally designed for destroying brain tumors. Rochester oncologists are expanding its use to other parts of the body, studying whether it can be used to destroy other soft-tissue tumors that were previously considered untreatable. This includes tumors in the liver, adrenal glands and spine.
Last year Paul Okunieff, M.D., and colleague Alan Katz, M.D., reported using the technology to achieve an 88 percent control rate for metastatic tumors in the liver, a result that was considered highly unlikely as recently as five years ago.
The current study was funded in part by BrainLab, the maker of the Novalis radiosurgery system. In the study of 50 patients, 91 percent of the lung tumors treated between February 2001 and December 2005 never progressed, and about 25 percent of patients appear to be disease-free after three years of follow-up.
Doctors hope that shaped-beam radiosurgery and chemotherapy might form a "synergistic combination that allows the drugs to destroy the microscopic cells that imaging studies can't see while the radiation therapy controls the tumors we can see," said Okunieff, chair of Radiation Oncology at the Medical Center's James P. Wilmot Cancer Center.
Perhaps most importantly, this high-dose, focused radiation targets the tumor with very limited damage to healthy tissue that surrounds the lesion, and patients experience minimal side effects even when a large number of tumors are treated, Okunieff said.
"We're getting better and better at finding smaller and smaller tumors that we can irradiate easily, and people are living longer," Okunieff said.