Scientists compared outcomes for 960 patients treated with three different regimens; survival rates vary from 91 percent for the newest treatments, which include monoclonal antibodies, to 69 percent for standard therapy.
"This is real evidence that the clinical advances we've made over the last 30 years are prolonging lives," said Richard I. Fisher, M.D., director of the Wilmot Cancer Center and lead author on a paper published online by the Journal of Clinical Oncology. "Some of the new therapies that include monoclonal antibodies have revolutionized treatment of this disease."
Follicular lymphoma, a slow-growing cancer of the lymphatic system, affects about 30,000 older adults each year in the U.S. Median survival has been seven to 10 years, but until this study, there was no evidence of any recent improvements.
Fisher and colleagues from the Southwest Oncology Group, Fred Hutchinson Cancer Research Center in Seattle and University of Arizona Cancer Center assessed three common therapies that have been used over the last two decades.
In the head-to-head comparison, they found that a combination of the standard therapy (a four-drug combination called CHOP, which stands for cyclophosphamide, doxorubicin, vincristine and prednisone) plus new monoclonal antibodies (rituximab or iodine-131 tositumomab) offers the best survival rate during the first four years. The team studied 179 patients who were treated with this regimen during the late 1990s, and the survival rate was 91 percent.
In the second arm of the study, the 425 patients treated during the 1980s with ProMACE-MOPP, an eight-drug, combo-chemotherapy regimen, had a 79-percent survival rate at the four-year point.
The third group of 356 patients received CHOP plus immunostimulant therapies during the 1970s; their four-year survival rate was 69 percent.
"This data gives doctors and patients real evidence that initial treatment decisions have significant impact on the length of survival," Fisher said.
Fisher has studied CHOP therapy and other combinations with the Southwest Oncology Group, one of the largest research cooperative groups, for the last three decades. He has led studies that demonstrated its effectiveness as a treatment for aggressive lymphomas.
The Wilmot Cancer Center has established one of the Northeast's largest hematologic malignancies teams, specializing in the multidisciplinary treatment of lymphomas and leukemias. Wilmot hematologists are currently comparing the two most effective therapies: CHOP plus rituximab and CHOP plus iodine-131 tositumomab.