Background: The "proximal-type" epithelioid sarcoma (PES) is a rare variant of conventional epithelioid sarcoma. It has been described in older patients in the proximal portion of the extremities with a predilection for the pelvis and perineum. It is clinically more aggressive, showing a higher incidence of recurrence, metastasis, resistance to chemotherapy and a higher mortality. We report the case of a patient with a PES of the pubic region and we review the previous literature.
Clinical case: We report the case of a 57-year-old female with a painless, progressively growing mass in the region of the pubis. We performed surgical resection of the lesion with clear margins and histological and immunohistochemical study allowed the definitive diagnosis of PES. After 4 disease-free years, the patient had a tumor recurrence at the same location. We performed en bloc resection of the lesion and immunohistochemical study confirmed the recurrence of PES. The patient refused adjuvant therapy. Today, after 4 years of follow-up, the patient remains asymptomatic and without evidence of recurrence or distant disease.
Conclusions: Diagnosis of PES is complex because histological findings may be confused with multiple tumors; therefore, immunohistochemical study is definitive. PES shows positivity for epithelial markers (cytokeratin and EMA), mesenchymal markers (vimentin) as well as CD34. According to what has been reported in the literature, surgical treatment with free margins is indicated, with adjuvant therapies when the risk of recurrence is high.