Patients with an early-stage, indolent form of lymphoma are increasingly being given no treatment, chemotherapy or targeted drug therapies despite strong clinical evidence that shows radiation therapy can have better outcomes, according to a study by University of Pittsburgh School of Medicine researchers that is being presented at the 57th Annual Meeting of the American Society for Radiation Oncology (ASTRO).
Guidelines from the National Comprehensive Cancer Network and the European Society for Medical Oncology both list radiation therapy as the preferred treatment for low-grade follicular lymphoma, which is a common type of non-Hodgkin lymphoma that grows slowly. It is most likely to occur in people age 60 and older.
Radiation therapy is the use of high-energy x-rays to treat cancer, and was the first curative therapy for lymphoma. Radiation therapy has a long history as the preferred treatment in early-stage follicular lymphoma; however, despite strong supporting evidence, it has been replaced by alternative management strategies including observation without initial treatment and novel systemic therapies.
"Our study highlights the increasing omission of radiation therapy in non-Hodgkin's lymphoma and its associated negative effect on overall survival at a national level. This increasing bias towards the omission of radiation therapy is despite proven efficacy and increasing adoption of lower radiation therapy doses and more modern radiation therapy techniques which decrease risk of side effects," said Austin Vargo, M.D., a radiation oncologist at UPMC CancerCenter, partner with the University of Pittsburgh Cancer Institute, and lead author of the study. "More patients should be offered this effective yet underused treatment."
Researchers analyzed patterns of care and survival outcomes for 35,961 patients diagnosed with early-stage follicular lymphoma as listed in the National Cancer Data Base. The study found that the use of radiation therapy in these patients decreased from 37 percent in 1999 to 24 percent in 2012 while there were increases in the use of single-agent chemotherapy and observation without any initial treatment. Patients who received radiation therapy had five-year and 10-year survival rates of 86 percent and 68 percent, respectively; those who did not have radiation therapy had rates of 74 percent and 54 percent.
"Survival with radiation therapy in these cases are higher and we think that an evidence-based approach should be used by more oncologists when discussing treatments for their patients," said Dwight E. Heron, M.D., FACRO, FACR, director of radiation services, UPMC CancerCenter, and professor of Pitt's Department of Radiation Oncology, Otolaryngology and Head & Neck Surgery.
Collaborators on the study were Beant S. Gill, M.D., of the University of Pittsburgh Cancer Institute; Goundappa K. Balasubramani, Ph.D., of the University of Pittsburgh Graduate School of Public Health; and Sushil Beriwal, M.D., Department of Radiation Oncology, Magee-Womens Hospital of UPMC.