Risk factors for the development of secondary malignancy after high-dose chemotherapy and autograft, with or without rituximab: A 20-year retrospective follow-up study in patients with lymphoma

Purpose: High-dose chemotherapy with peripheral blood progenitor cell (PBPC) autograft is effective in high-risk lymphoma, particularly with the addition of rituximab; however, it is associated with risk of secondary malignancy. These issues have been addressed in a series of 1,347 patients with lymphoma treated with a high-dose sequential (HDS) program. Patients and Methods: A total of 1,024 patients with B-cell lymphoma, 234 patients with Hodgkin's lymphoma, and 89 patients with T-cell lymphoma were treated with HDS between 1985 and 2005 at 11 Gruppo Italiano Terapie Innovative Linfomi centers. HDS was given as salvage treatment to 707 patients (52%); 655 patients (49%) received a modified HDS, with high-dose cytarabine and two consecutive PBPC harvests. Rituximab-supplemented HDS was given to 523 patients (39%). Results: At a median follow-up of 7 years, the median overall survival (OS) was 16.2 years; in B-cell lymphoma the OS was significantly superior with rituximab HDS compared to HDS alone. The cumulative incidence at 5 and 10 years of secondary myelodysplasia/acute leukemia (sMDS/AL) were 3.09% and 4.52%, respectively, that of solid tumors were 2.54% and 6.79%, respectively. Factors associated with sMDS/AL were male sex and use of the second harvest PBPC for the graft; factors found to be associated with solid tumor were advanced age, post-HDS radiotherapy, and rituximab addition to HDS. Despite the increased risk of solid tumors, rituximab addition to HDS was still associated with survival advantages. Conclusion: This analysis has relevant implications for the design and use of intensive chemoimmunotherapy with autograft. In addition, it offers useful insights toward the understanding and prevention of tumor development.