Non-Hodgkin's lymphoma after primary Hodgkin's disease in the German Hodgkin's Lymphoma Study Group: Incidence, treatment, and prognosis

Purpose: The cumulative incidence for non-Hodgkin lymphoma's (NHL) after pr imary Hodgkin's disease (HD) ranges between 1% and 6%. to investigate the c ourse of disease for secondary NHL, we retrospectively analyzed patients tr eated within clinical trials of the German P Hodgkin's Lymphoma Study Group (GHSG) since 1981. Patients and Methods: From 1981 to 1998, the GHSG conducted three generatio ns of clinical trials for the treatment of primary HD involving a total of 5,406 patients. Reference histology by an expert panel was obtained for 4,1 04 of the patients. Data on incidence, treatment, and outcome of secondary NHL were updated in March 1999. Results: At first diagnosis of HD, the pathologists rejected 114 (2.1%) of 5,520 cases initially diagnosed as HE and rediagnosed them as primary NHL. Fifty-two (0.9%) of the remaining 5,406 patients developed a secondary NHL. One patient was excluded from further analyses because of insufficient doc umentation. Six patients had no further therapy because of patient refusal (n = 1) or rapidly progressive disease (n = 5). For the remaining 45 patien ts, overall response rate was 43% (36% complete response and 7% partial res ponse). The actuarial 2-year freedom from treatment failure (FFTF) and over all survival (OS) for all patients was 24% and 30%, respectively, and for p atients with diffuse large-cell lymphoma, it was 28% and 35%, respectively. Time of occurrence of secondary NHL after first diagnosis of HD and variab les employed in the age-adjusted International Prognostic Factor Index (IPF I) significantly influenced treatment outcome. Conclusion: In the GHSG, the incidence of secondary NHL with 0.9% is relati vely low compared with previously reported series. The prognosis of seconda ry NHL seems dismal and is significantly influenced by time of occurrence a nd the age-adjusted IPFI. In a subset of patients with secondary NHL, long- term disease-free survival could be achieved. (C) 2001 by American Society of Clinical Oncology.