Bladder Myeloid Sarcoma with TP53 mutated Myelodysplastic Syndrome/Myeloproliferative Neoplasm Overlap syndrome: Response to Decitabine-Venetoclax regimen

Abstract

Myeloid sarcoma (MS) is a rare extramedullary blast proliferation of immature cells of myeloid origin. It is commonly associated with acute myeloid leukemia (AML), myelodysplastic syndrome (MDS), or myeloproliferative neoplasm (MPN), and may precede, coincide with, or follow the diagnosis of a myeloid disorder. MS treatment is controversial, but AML induction like regimens is usually recommended. We present an unusual case of de novo TP53 mutated MDS/MPN overlap with bladder MS. Due to the high-risk nature of the disease, the patient was induced with decitabine and venetoclax combination therapy, resulting in complete remission. The response was further consolidated by an allogeneic hematopoietic stem cell transplantation.

Lymph node myeloid sarcoma with TP53‑associated myelodysplastic syndrome: A case report

“…It has also been reported that a patient with bladder MS with TP53 mutation achieved a significant improvement in symptoms and achieved complete CR in the first cycle of 20 mg decitabine treatment combined with induction chemotherapy. Due to the consideration of high-risk cytogenetics and TP53 mutations, subsequent allo-HCT was performed for consolidation ( 4 ). Similarly, the patient reported in the present study was treated with decitabine combined chemotherapy and achieved CR after the first chemotherapy.…”

“…Decitabine is often used to treat elderly patients with AML or patients with high-risk chemoresistant phenotypes (23). Some studies have confirmed the efficacy of decitabine in the treatment of MS, reporting that it can induce long-term remission (4,24). In a Surveillance, Epidemiology and End Results database analysis, Liang et al (13) found that when using overall survival as an indicator of efficacy, patients with non-isolated MS showed an improved response to cytarabine-based AML chemotherapy regimens.…”

“…Occasionally, MS develops as an isolated lesion, with a wide variation in size and location, accounting for 2 cases per million adults ( 3 ). MS is described in ~9% of patients with AML as an early manifestation of the disease, or is in the relapsed setting, which is observed frequently after allogeneic hematopoietic stem cell transplantation (allo-HCT) ( 4 ). The diagnosis of MS is mainly based on clinical manifestations and cytochemical and/or immunophenotypic factors.…”

“…However, recent whole-genome sequencing analyses have revealed more frequent alterations in TP53, including structural alterations in TP53 intron 1 ( 11 ). TP53 + -MS is often accompanied by complex chromosome karyotypes ( 4 ).…”

“…It has been reported that 70% of osteosarcomas have structural variations or mutations of TP53 ( 10 ). In TP53-mutant AML, decitabine-based hypomethylation chemotherapy has certain advantages ( 4 ). One study showed a 100% response rate in TP53 mut AML and high mutation clearance with a 10-day regimen of decitabine ( 12 ).…”