RESUMEN
Ewing's sarcoma/primitive neuroectodermal tumor is rare and aggressive with a poor prognosis. Intraabdominal metastases are an uncommon condition. Metastasis in the lesser sac is an exceptional occurrence. To the best of our knowledge, this location has not been described previously. We report a case of a 15-year-old patient treated for Ewing's sarcoma of the left arm 6 years back. She had developed a suspicious mass in the lesser sac 6 years following her primary tumor. The histopathologic exam revealed a tumor with "small round cells" that were positive for CD99, confirming the relapse of Ewing's sarcoma. The relapse was successfully managed with chemotherapy and surgery. Intraabdominal, extraintestinal masses in patients treated previously for Ewing's sarcoma should be considered as Ewing's sarcoma relapse in the differential diagnosis. We fully describe the management of this atypical relapse, with different components of clinical, radiological, and histological findings.
RESUMEN
Dermatofibrosarcoma protuberans (DFSP) is a rare sarcoma of soft tissue representing about 1% of all tumors. In addition, DFSP occurs commonly on the trunk and extremities, and only a few cases of DFSP have been observed on the breast. In men, only 11 cases, including this case, have been reported. In this article, we present a case of left breast DFSP that occurred in a 44-year-old man. The physical examination revealed a left breast tender mass, which invaded the skin. The tumor was staged as T4b N0 M0. Mammography and sonography showed a suspect mass of the left breast. The biopsy and immunochemistry permitted the diagnosis of DFSP of the left breast. The patient had a left mammectomy, with free margins. He presents no evident sign of recurrence 7 months later.