A phase II trial of adjuvant low-dose total body irradiation in non-hodgkin's lymphoma patients following standard CHOP

Abstract

Because survival results achieved in aggressive NHL with the standard CHOP are not very satisfactory, we investigated adding adjuvant low-dose total body irradiation (LTBI) to standard CHOP in a phase II trial. Thirty-six patients were included between September 1999 and September 2001. All patients were in documented complete remission (CR) after the end of their standard CHOP. LTBI started 4–6 weeks following the last CHOP course and was given in two courses, each with 4 daily fractions of 0.2 Gy, separated by 2 weeks of rest. Patients with bulky disease received involved-field radiotherapy on initial bulky sites starting 4–6 weeks after the last LTBI fraction. Primary end points were disease-free survival (DFS) and overall survival (OS) and the secondary end point was toxicity. The toxicities of LTBI were temporary thrombocytopenia and leucopenia (requiring no transfusions or treatment with growth factors). The 3-year DFS was 61%±9% and the overall survival was 87±6%. Univariate analysis showed time to achieve CR, and whether the patient got LTBI-induced haematological toxicity to be 2 significant prognostic factors affecting DFS. The use of adjuvant LTBI in patients with aggressive NHL in CR after standard chemotherapy is a feasible, non-toxic treatment that is worthy of testing in a future phase III trial.