Primary breast diffuse large B-cell lymphoma in the rituximab era: A retrospective study of the Chinese Southwest Oncology Group.

BACKGROUND: Primary breast diffuse large B-cell lymphoma (PB-DLBCL) is a rare subtype of extranodal DLBCL, and the standard treatment remains controversial. In this study, we aimed to define the optimal treatment management in the rituximab era. METHODS: A total of 5089 newly diagnosed DLBCL patients treated with rituximab-containing immunochemotherapy between 2008 and 2019 from the Chinese Southwest Oncology Group-affiliated institutes were identified, of whom 135 diagnosed with PB-DLBCL were eligible for this analysis. RESULTS: PB-DLBCL accounted for 2.7% of all DLBCLs. With a median follow-up of 4.2 years, the 5-year overall survival and progression-free survival rates were 84.8% and 71.6%, respectively. Breast and central nervous system (CNS) relapses were the main cause of treatment failure. We observed that consolidative breast radiotherapy (RT) significantly decreased breast relapse risk (5-year risk, 2.9% vs. 20.1%, p = 0.007). The CNS relapse risk was lower for patients who received high-dose methotrexate (HD-MTX) than for patients who did not (5-year risk, 0% vs. 15.2%, p = 0.015). We further screened the genetic mutation profile of 20 patients from two institutes, and found that MYD88 (25%) and CD79B mutations (25%) frequently occur in PB-DLBCL. In addition, four patients with MYD88 and/or CD79B mutations experienced CNS relapse, while three patients with MYD88 and/or CD79B mutations who received HD-MTX did not experience CNS relapse. CONCLUSION: Collectively, our results indicate combined modality therapy including rituximab-containing immunochemotherapy and consolidative breast RT is a promising approach for PB-DLBCL, while HD-MTX is useful for preventing CNS relapse.

Hematopoietic Stem Cell Transplantation in Nepal: International Partnership, Implementation Steps, and Clinical Outcomes.

Blood and marrow transplantation (BMT) is rarely available in many low- to middle-income countries (LMICs). In 2012, Civil Service Hospital, a government hospital in Kathmandu, partnered with the University of Illinois at Chicago to consult on the establishment of BMT in their hospital, train staff, and promote educational activities. The implementation of BMT occurred in 3 phases over 4 years and included regular onsite visits, training of personnel in Chicago, continuous remote communication, and co-organization of educational events in Kathmandu. The Nepalese government funded the construction of a state-of-the art BMT unit and stem cell laboratory inside Civil Hospital. Autologous (auto) hematopoietic stem cell transplantation (HSCT) was started in 2016, and allogeneic (allo) HSCT from matched related donors (MRDs) or haploidentical (haplo) donors was initiated in 2017. The cost of transplantation was $5200 for auto-HSCT, $10,000 for MRD HSCT, and $13,300 for haplo HSCT. The major socioeconomic determinants reported by Nepalese BMT providers were the cost of transplantation, loss of revenue of the patient and/or caregiver, and cost of transportation. All patients (n = 66) received peripheral blood stem cell grafts, and all allo-HSCT recipients were given post-transplantation cyclophosphamide as graft-versus-host disease (GVHD) prophylaxis. Among recipients of auto-HSCT (n = 30), with a median follow-up of 1029 days (range, 130 to 1653 days), 87% were alive, and transplantation-related mortality (TRM) was 10%. Among allo-HSCT recipients (n = 36), all patients engrafted, and at a median follow-up of 204 days (range, 12 to 1131 days), 75% of them were alive (MRD, 71%; haplo, 83%), with a TRM of 19%. Only 3 of 36 patients developed acute GVHD grade II-IV. The median overall survival in auto-HSCT recipients was 1610 days and was not reached in allo-HSCT recipients. The long-lasting partnership with University of Illinois at Chicago helped build capacity and allowed the Civil Service Hospital team to establish a BMT program in Nepal that has high quality standards at an affordable cost for the majority of patients.