Extraskeletal myxoid chondrosarcoma. Long-term experience with chemotherapy.

Extraskeletal myxoid chondrosarcoma (EMC) is a rare low-grade soft tissue sarcoma that has been reported to have an indolent nature history, and relatively good prognosis. The majority of primary tumors are located in the extremities and they tend to be bulky at presentation. Studies with long-term follow-up have revealed the development of distant metastases in virtually all patients, eventually resulting in death. We reviewed our experience with EMC over the last three decades. The patient population was identified through a search of the database maintained by the Departments of Patient Studies, Pathology, and Melanoma-Sarcoma Medical Oncology. Eleven patients with histologically confirmed diagnosis of EMC were identified. The median age was 59 (37-81 years), and there were nine males and two females. Nine patients had an extremity location and the remaining two had a chest wall and abdominal wall primary, respectively. The median size of the primary tumor was 10 cm (range: 4-17 cm) in maximum dimension. Ten of the eleven patients received chemotherapy, mainly with doxorubicin- and dacarbazine-based regimens. One patient is currently on beta-interferon. No objective responses were noted, to a median of 4 (2-6) cycles of chemotherapy. Three patients were treated with ifosfamide as a second-line chemotherapy without any benefit. Three patients have expired, two patients are alive with no evidence of disease, and six patients are alive with disease. The median follow-up is 5 years (range: 1.33-17 years) from diagnosis. Although small numbers preclude adequate assessment, there is no evidence of efficacy of standard soft-tissue sarcoma chemotherapy in patients with EMC.