Abstract
The role of involved field radiation therapy (IF‐RT) after high dose chemotherapy (HDC) with autologous stem cell transplantation (ASCT) for non‐Hodgkin's lymphoma (NHL) has not been conclusively defined. It has been hypothesized that HDC might obviate the need of consolidative IF‐RT. A retrospective matched‐pair analysis of patients undergoing HDC and ASCT with or without consolidative IF‐RT has been performed. Fifteen patients treated with IF‐RT after ASCT were compared with 15 patients without IF‐RT, identical for histology, stage and treatment response to HDC/ASCT as well as comparable for international prognostic index (IPI) score, age and gender. After a mean follow‐up time of 65 ± 45 months, none of the patients with consolidative IF‐RT following HDC and ASCT relapsed within the involved field compared to six patients without consolidative IF‐RT (IF‐failure risk at 5 years: 0% vs. 40%; p < 0.005). In most of the cases, local relapse was seen in patients with bulky disease. The 5‐year risk for loco‐regional failure was 7% after consolidative IF‐RT and 38% in patients without IF‐RT (p = 0.02) while the 5‐year risk for developing distant recurrences was similar in both groups (30% with IF‐RT vs. 35% non‐IF‐RT; p = 0.7). Overall survival at 5 years was similar with 79% (IF‐RT) and 65% (non‐IF‐RT), respectively (p = 0.2). Acute toxicity due to consolidative IF‐RT was mild in most cases and severe acute toxicity was noticed in only one patient (7%). Long‐term toxicities observed after IF‐RT were coronary artery disease, secondary malignancy unrelated to the RT‐field, angina abdominalis, hypothyroidism and teeth decay. Recurrence of NHL at sites of macroscopic disease remains common despite HDC. IF‐RT achieves excellent local regional control and consolidative IF‐RT after ASCT seems indicated, particularly in patients with bulky disease. In the absence of a prospective randomized trial and proven impact on survival rates, IF‐RT can be recommended as an option post‐ASCT to enhance local disease control. Copyright © 2007 John Wiley & Sons, Ltd.