Myxoid liposarcoma. Experience with chemotherapy

Background. Myxoid liposarcoma (ML) is the most common type of liposarcoma. It has been classified as an intermediate grade tumor with a definite metastatic potential but a relatively indolent natural history. Little is known about its sensitivity to chemotherapy. Method. The authors reviewed their experience with chemotherapy in ML from 1986 to 1992. The patient population was identified through a search of the database maintained by the Department of Melanoma‐Sarcoma Medical Oncology of the M. D. Anderson Cancer Center. Results. Forty‐four patients each with a histologically confirmed diagnosis of ML were identified. Twenty one were treated with chemotherapy. The median age was 45 years (31‐69 years); there were 14 men and 7 women. The ML in 19 patients was in the lower extremity, one in the head and neck, and one pelvic. The median size of the primary tumor was 15 cm (range, 7‐48 cm) in maximum dimension. Of the 18 patients who received doxorubicin‐ and dacarbazine‐based chemotherapy as a frontline regimen [median of 3 (2‐9) cycles] and were evaluable for response, 8 (1 completed response, 7 partial responses) achieved an objective response (44%, 95% confidence interval 21‐67%). Two of the remaining three patients who were also treated with a similar regimen were not evaluable for response (one received chemotherapy postoperatively, and the other received concomitant radiation and doxorubicin), and the third patient received ifosfamide as frontline chemotherapy because of a significant cardiac history. Seven patients received chemotherapy in the neoadjuvant setting, 13 for recurrent ormetastatic disease, and 1 postoperatively after complete tumor resection. At the last follow‐up, 10 patients were alive with no evidence of disease, 3 were alive with disease, and 8 had died. The median follow‐up was 51 months (range, 6‐199 months) from diagnosis. Conclusion. The authors conclude that doxorubicin and dacarbazine‐based chemotherapy is effective in the treatment of ML.