Durable Hematologic Response in Therapy-Related Myelodysplastic Syndrome During Nivolumab Treatment for Metastatic Melanoma: A Case Report.

Immunotherapy is the standard first-line palliative treatment for metastatic melanoma; however, its role in myelodysplastic syndrome (MDS) remains uncertain. We report a case in which nivolumab, administered for metastatic melanoma, was associated with a marked improvement in concurrent treatment-related MDS. A 67-year-old man with a history of oligosecretory multiple myeloma developed transfusion-dependent MDS following autologous stem cell transplantation, requiring twice-weekly blood transfusions. He subsequently developed metastatic melanoma and was treated with single agent nivolumab to minimize treatment-related toxicity. Nivolumab effectively controlled the melanoma, and during treatment the patient experienced a durable hematologic response with sustained transfusion independence. At approximately two years of follow up, he remained transfusion-independent with stable peripheral blood counts, supporting the durability of the hematologic response. Although checkpoint inhibitors are not established therapies for therapy-related MDS and a causal relationship cannot be confirmed from a single case, the timing and sustained nature of the response are noteworthy. The patient experienced a significant improvement in quality of life with minimal adverse effects. This case adds to the limited literature on checkpoint inhibition in MDS and supports further investigation of its potential effects on hematologic recovery.