Long-term complication in follicular lymphoma: assessing the risk of secondary neoplasm in 242 patients treated or not with 90-yttrium-ibritumomab-tiuxetan.

BACKGROUND: Non-Hodgkin lymphoma patients have a 25% increased risk of secondary primary neoplasms (SPNs). Regarding the controversy about the increased risk of SPN in patients exposed to radioimmunotherapy (RIT), we have analyzed this issue in a cohort of follicular lymphoma (FL) patients treated with/without RIT.

PATIENTS AND METHODS: A retrospective study including all consecutive FL patients diagnosed since 2001 was performed. Demographic, clinical data including the incidence of any kind of neoplasm (excluding basocellular skin carcinoma) were recorded.

RESULTS: A total of 242 patients were registered, male/female: 103/139, mean age: 59.9 yr (15-86), stage IV (57.8%), and Follicular Lymphoma Prognostic Index (FLIPI) low-risk (62.15%) predominance. Ninety-six patients (39.7%) were treated with 90Y-IT. The median follow-up for patients treated or not with 90Y-IT was 61 (8-273) and 38 (1-171) months. With respect to SPN incidence, 38 (15.6%) patients have at least two cancers, in 17 (44.7%), FL was the SPN; for the rest (226), the global incidence of SPNs was 9.3% (21), but there were no differences related to the exposition or not to 90Y-IT (P = 0.26). In seven patients, more than two (2-6) different therapies were registered; four were exposed to fludarabine-based therapy, three to radiotherapy and two to autologous stem-cell transplantation, and in the RIT cohort, two patients developed myelodysplastic syndrome.

CONCLUSION: This is one of the largest single institution reports assessing the risk of SPN in FL patients treated (96) or not (146) with 90Y-IT. It seems that 90Y-IT does not increase significantly the risk of SPN but avoiding its use after fludarabine and other intense cytotoxic schemes is recommended.