Oxaliplatin is a third-generation platinum compound widely used to treat gastrointestinal malignancy. One of the major side effects of oxaliplatin is thrombocytopenia, the development of which can limit appropriate treatment. We report a 38-year-old man with advanced gastric cancer who developed severe thrombocytopenia after FOLFOX4 (oxaliplatin, leucovorin, and fluorouracil) chemotherapy. The thrombocytopenia was associated with therapy-related myelodysplastic syndrome after cytotoxic chemotherapy and was confirmed by bone marrow biopsy and genetic study. Therefore, physicians should be aware of therapy-related hematologic complications, especially with an oxaliplatin-based chemoregimen, and might consider the bone marrow study in those patients.

Keywords: Gastric cancer, Oxaliplatin, Myelodysplastic syndrome, Side effect