Initially recognized in the 1980s, primary mediastinal B-cell lymphoma (PMBCL) is a subtype of diffuse large B-cell lymphoma (DLBCL) arising in the thymus. Representing less than 3% of non-Hodgkin lymphoma cases, PMBCL has a skewed age distribution affecting young adults, especially young women. Historically, patients with PMBCL have been treated with mediastinal radiation following chemotherapy based on evidence that chemotherapy alone was insufficient. Despite the high cure rates with this strategy, mediastinal radiation in young patients can be associated with late adverse effects, including premature cardiovascular disease and secondary cancers.
Researchers from the National Cancer Institute (NCI) and their partner institutions recently completed a phase II study of infusional dose-adjusted etoposide, doxorubicin, and cyclophosphamide with vincristine, prednisone, and rituximab (DA-EPOCH-R) with no mediastinal radiation complement. In 51 patients with a median age of 30 years, of which 59% were women, the overall survival rate was 97% at the median 5-year follow-up. From these results, researchers suggested that DA-EPOCH-R therapy obviated the need for radiotherapy in patients with PMBCL.
While these results from this phase II study are encouraging, they will need to be confirmed with further research.