Radiation therapy

Long-term disease control within radiation fields can be achieved in a significant number of patients with indolent stage I or stage II NHL by using radiation therapy. This requires dosages of radiation that usually range from 25 Gy to 40 Gy to involved sites or to extended fields that cover adjacent nodal sites.[1,4-6] Almost one-half of all patients treated with radiation therapy alone will have out-of-field relapse within 10 years.[1,6,7]

A retrospective review of 512 patients from an international consortium evaluated patients with early-stage follicular lymphoma who received at least 24 Gy of localized radiation therapy at initial presentation. With a median follow-up of 52 months, 29.1% of patients developed recurrent lymphoma at a median of 23 months (range, 1−143 months).[8] With a median follow-up of 33 months after relapse, the 3-year OS rate was 91.4% after patients received subsequent systemic chemotherapy that involved rituximab.[8]

Very low-dose radiation therapy with 4 Gy (2 Gy × 2 fractions) can result in 50% remission rates for patients who cannot tolerate higher doses.[9] In a multicenter, randomized, prospective trial, 548 patients with follicular or marginal zone lymphoma received radiation therapy, either 4 Gy in 2 fractions or 24 Gy in 12 fractions.[10]