Therapy-related myeloid neoplasm with bone marrow involvement, myelosarcoma, and a t(8;16)(p11.2;p13.3)-a case report.

Therapy-related leukemia is a well-documented complication of conventional therapy for cancer. Therapy-related acute myeloid leukemia (t-AML) is grouped along with therapy-related myelodysplastic syndrome (t-MDS) and therapy-related myelodysplastic syndrome/myeloproliferative neoplasms (t-MDS/MPNs) as therapy-related myeloid neoplasms (t-MNs) by the 2008 World Health Organization classification system. Therapy-related myeloid neoplasms differ clinically from their de novo counterparts in terms of response to therapy, aggressiveness of disease, and associated poor prognosis. The occurrence of extramedullary myeloid sarcomas with bone marrow involvement has been shown to be a poor prognostic indicator for patients with t-MN. The karyotype of leukemic blasts has also been reported to have a significant impact in t-MN and may predict survival and outcomes in patients. The t(8;16)(p11.2;p13.3) is a rare, balanced translocation that is frequently associated with the M4/M5 subtype of de novo acute myeloid leukemia. It has also been reported in patients with t-MN, typically in those with poor outcomes. Here we report a case of t-MN with myeloid sarcoma and bone marrow involvement in an adult patient with a karyotype of 47,XY,t(8;16)(p11.2;p13.3),+21 after rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) chemotherapy for follicular lymphoma.