LOS ANGELES—Patients with early-stage diffuse large B-cell lymphoma (DLBCL) have improved long-term disease-free and overall survival if their first-line treatment includes radiation therapy, according to the largest outcomes study to date among this population.

"Despite a handful of published randomized trials for stage I-II diffuse large B-cell lymphoma, there is virtually no long-term outcome information for these patients, defined as greater than 5 to 7 years. Clinical trial design and standard of care treatment typically address all early-stage patients uniformly, presuming that all patients with stage I-II disease have similar relapse risks," Rachel Rabinovitch, MD, explained.

She said that outcome data are virtually nonexistent for discrete, clinically meaningful patient subsets, "and recent clinical trial data have resulted in seemingly contradictory conclusions about the role of radiotherapy, particularly in the elderly."

SEER search

In the study, presented at the 49th annual ASTRO meeting (abstract 27), Dr. Rabinovitch and her colleagues at the University of Colorado searched the SEER database for patients receiving a diagnosis of stage I, Ie, II, or IIe DLBCL between 1988 and 2003 who had follow-up of at least 6 months. A total of 13,240 patients were identified.

"We were surprised that radiotherapy was only delivered in 41% of all early-stage patients," Dr. Rabinovitch commented.

She noted that SEER indicates whether patients received radiation as part of their first treatment course, but lacks other important data, such as lactate dehydrogenase (LDH) level, performance status, comorbidities, and systemic therapy.