Diagnosis and Management of Large Extraosseous Myxoid Chondrosarcoma of the Buttocks: A Case Report.

BACKGROUND Extraskeletal chondrosarcoma is a rare soft tissue sarcoma with no characteristic imaging and clinical manifestations. Therefore, early preoperative diagnosis is difficult and ultimately depends on postoperative pathology and genetic diagnosis. CASE REPORT A 67-year-old man presented with a huge buttock tumor. The maximum transverse section length of the tumor was 40 cm. Due to the large size and long duration of the tumor, the tumor ruptured and invaded part of the sacrum. The preoperative diagnosis was not clear, the tumor was completely removed by surgery, and the wound was repaired. Adjuvant radiotherapy was given after surgery, and the prognosis was good. CONCLUSIONS This case report demonstrates the importance of radical surgical resection and postoperative adjuvant chemotherapy for the prognosis of extraosseous chondrosarcoma. It also suggests that sometimes the early diagnosis of this type of tumor is difficult, depending on postoperative pathology and genetic diagnosis.