Favorable Response to Immunosuppressive Therapy in Severe Aplastic Anemia With Trisomy 8 and BCOR Mutation: Sustained Hematologic Response Despite Evolving Mutational Profile-A Case Report.

Severe aplastic anemia (SAA) is a serious medical condition that is characterized by its abrupt onset, rapid progression of the disease, and alarmingly high mortality rate, making it a significant concern in the field of hematology. Intensive immunosuppressive therapy (IST) is one of the primary therapeutic options; however, some SAA patients do not respond to initial IST treatment. For these patients, salvage treatment remains a significant challenge. Consequently, predicting the efficacy of IST for SAA at initial diagnosis and developing the optimal curative regimen could potentially enhance treatment outcomes. The concurrent presence of trisomy 8 and a BCL6 corepressor (BCOR) mutation in SAA is uncommon and may independently predict the efficacy of IST. In this case report, we presented a SAA patient exhibiting both trisomy 8 and a BCOR mutation at diagnosis. The bone marrow (BM) aspirate showed hypocellular BM and the bone marrow biopsy revealed a severe hypocellular bone marrow (15% cellularity). The patient experienced rapid clinical improvement, evidenced by reduced transfusion requirements and a favorable response to IST. Approximately two year's post-IST, a follow-up biopsy indicated remission, with the volume of hematopoietic tissue increasing to 40%. Cytogenetic analysis showed a normal karyotype, and no BCOR mutation was detected by next-generation sequencing (NGS). Complete blood cell count results also showed improvement. In conclusion, we are the first to report a rare case of SAA characterized by the simultaneous presence of chromosome 8 abnormality and BCOR mutation in detail, which may represent a new distinct entity in SAA.