Cutaneous and subcutaneous Ewing's sarcoma: An indolent disease

Purpose: The occurrence of extraosseous Ewing's sarcoma (ES) in deep soft t issues has been well described, but cases in which this tumor occurs in a p rimary cutaneous or subcutaneous site have rarely been reported. The superf icial variant may be less aggressive than are the more common bony and deep soft tissue counterparts with an apparently favorable outcome. A retrospec tive review of patients with cutaneous or subcutaneous ES was conducted to analyze outcome and patterns of failure, Methods and Materials: Between July 1985 and March 1997, 14 patients with c utaneous or subcutaneous ES were treated at St, Jude Children's Research Ho spital. The median age at presentation was 16 years (range 7-21 years). Ana tomic locations included trunk and pelvis (7), upper or lower extremity (4) , and head and neck (3). The median size of the lesion was 3 cm (range, 1-1 2 cm), Thirteen had definitive surgical resections, and one had biopsy of t he mass at the time of referral. They were enrolled on institutional (12) o r cooperative group (2) protocols. All patients received chemotherapy, comp osed of vincristine, doxorubicin, cyclophosphamide, ifosfamide, etoposide, and dactinomycin. Patients on institutional protocols received radiation (3 6 Gy) to the operative bed (150-180 cGy/fraction/day). Postoperative radiot herapy was omitted for 2 patients who had complete resection on the coopera tive group study. Results: No patients had metastatic disease at presentation. Thirteen patie nts had wide local excision of the primary tumors prior to enrollment on ch emotherapy; surgical margins were negative (10), microscopically positive ( 2), and indeterminate (1). Eleven patients received radiotherapy to the tum or bed; 2 with clear surgical margins were treated without irradiation. The patient who had biopsy only received induction chemotherapy followed by de finitive surgical resection and postoperative radiotherapy, The median foll ow-up was 77 months (range 17-111 months). None of the patients has develop ed local recurrence or distant metastasis. Several of the patients develope d treatment-related sequelae, including veno-occlusive disease of the lung and hemorrhagic cystitis (1), myelodysplastic syndrome (1), chemotherapy-in duced ovarian failure (1), moist desquamation (1), and dermatofibroma withi n the radiotherapy volumes (1). Conclusions: Cutaneous and subcutaneous ES are associated with an indolent course and a favorable prognosis when treated with combined modality therap y. Elimination of radiation therapy following complete resection has been t ested in the POG 9354 trial. The high rate of local control, low rate of me tastatic disease, and excellent overall outcome may suggest a role for less intensive chemotherapy, as well as tailoring to diminish or avoid radiatio n therapy in completely resected cases, with a goal to minimize toxicity wh ile maintaining a high cure rate. (C) 2000 Elsevier Science Inc.