Soft Tissue Sarcoma with Platelet Transfusion Refractoriness due to Production of Anti-HLA Antibodies

Abstract

We report a case of soft tissue sarcoma involving a patient with refractoriness to platelet transfusion (PTR) due to the production of anti-HLA antibodies. The patient was a 49-year-old pregnant woman who had a huge mass with pain in the right thigh. Biopsy was performed and pathological diagnosis was synovial sarcoma. Since the tumor was very close to major nerves and involved major blood vessels, we performed radio-hyperthermo-chemotherapy (RHC) before surgery. After five courses of RHC, tumor cleary shrinked. We then performed marginal resection, and histlogical necrosis on the large cut section was over 95%. She was administered with a couple of blood transfusions during the operation. One month after operation, we performed adjuvant chemotherapy consisting of ifosfamide and etoposide. Pancytopenia gradually developed. On day 12, platelet transfusion was needed for thrombocytopenia. However, the corrected platelet count increment (CCI) was only 2×103/ul, indicating the development of PTR. Anti-HLA antibody was detected by the AHG-LCT and FlowPRA methods, and HLA-matched platelet transfuions were successful in boosting platelet level of the patient. Anti-HLA antibodies, which are produced during pregnancy and blood transfusion, often cause PTR. Although HLA-compatible platelet transfusion is the only way to counteract PTR, it is difficult to prepare HLA-matched concentrated platelets immediately. Therefore, we concluded that it may be necessary to perform anti-HLA screening before high-dose chemotherapy, especially for pregnant women.