BACKGROUND AND OBJECTIVE: Retroperitoneal sarcoma constitutes 3-5% of all soft-tissue sarcomas and is often detected around 50 years of age. Soft-tissue sarcomas are categorized into four different types of well-differentiated, undifferentiated, myxoid and pleomorphic cells. Myxoid cells tend to cause lower-extremity involvement. In this study, we present a case of sarcoma of the right side of adrenal gland in a 46-year-old woman as a rare and important differential diagnosis of adenoma.

CASE REPORT: A 46-year-old woman referred to the Endocrine Clinic of Ayatollah Rohani Hospital of Babol to examine a 13 cm mass, which was randomly detected on the right side of adrenal gland via abdominal sonography. Sonography was requested due to flank pain, accompanied by night fever. Hormonal evaluation was negative and surgery was performed due to the large size of tumor mass. Pathological reports were indicative of a low-grade myxoid tumor. During four months of follow-up, the patient experienced no particular complications and underwent radiotherapy on a regular basis.

CONCLUSION: According to the results of this study, retroperitoneal masses can be posed  in the rare differential diagnosis of adrenal tumors