Potential Benefit of Involved-Field Radiotherapy for Patients With Relapsed-Refractory Hodgkin's Lymphoma With Incomplete Response Before Autologous Stem Cell Transplantation.

INTRODUCTION: We investigated for a possible role for peritransplantation involved-field radiotherapy (IFRT) by comparing patients who received IFRT before after autologous stem cell transplantation (ASCT) and patients who received salvage chemotherapy (CT) alone. PATIENTS AND METHODS: We retrospectively evaluated 73 consecutive patients with Hodgkin lymphoma treated with ASCT between 2003 and 2014. Twenty-one patients (28.8%) received peritransplantation radiotherapy. A Cox regression analysis (multivariate analysis; MVA) was performed to evaluate the prognostic role of any risk factor. Overall survival (OS) and progression-free survival (PFS) were calculated from the date of ASCT. Response to CT and ASCT were evaluated with positron emission tomography (PET) scan. RESULTS: Median follow-up was 41 months (range, 1-136 months). Overall, no significant difference appeared between patients who received IFRT and patients treated with CT alone; however, patients who were treated with IFRT had worse prognostic factors. In the MVA, advanced stage at relapse and persistent disease before ASCT (evident on PET scan [PET+]) were related to worse PFS and OS. In patients with limited stage disease at relapse and PET+, peritransplantation radiotherapy showed higher 3-year OS rates (91.7% vs. 62.3%) and PFS rates (67.5% vs. 50%) compared with patients treated with CT alone, although this difference was not significant (P = .14 and P = .22, respectively). CONCLUSION: IFRT used before or after ASCT might partially compensate for worse prognostic factors among the overall population; subgroup analysis showed a trend for survival benefit at 3 years in patients with limited stage disease at relapse and PET+ before ASCT.