A Case of Clinical Drug-Induced Thrombocytopenia During Chemotherapy for Colon Cancer

A case of drug-induced thrombocytopenia during chemotherapy for colon cancer is described. A 70-year-old female had been found to have advanced cecal cancer with simultaneous multiple metastases of the lung and paraaortic nodes (T3 N3 M1b Stage IV) 3 years earlier, and received chemotherapy with mFOLFOX6 plus bevacizumab. When she was admitted for the 22nd course of chemotherapy, twelve hours after the start of chemotherapy, gingiva and lip bleeding as well as purpura occurred. A blood exam showed that the platelet count had decreased from 13.7×104/mm3 to 0.2×104/mm3. She was treated with concentrated platelet transfusion and steroids. The bleeding stopped and the results of blood exams normalized. The level of platelet-associated IgG was high (961 ng/107 cells) and the results of drug lymphocyte stimulation tests for bevacizumab, 5-FU, and oxaliplatin were positive. We made a diagnosis of drug-induced thrombocytopenia.