Incidental diagnosis of a retroperitoneal schwannoma in a patient with chronic leukemia undergoing prostatic biopsy.

We present a case of retroperitoneal schwannoma incidentally diagnosed in a patient undergoing surgical drainage of a pelvic abscess as a complication of a prostatic biopsy. A 50-year-old male, suffering from lymphatic leukemia, came to our observation due to lichen ruber planus and ejaculatory pain. The patient underwent a trans-perineal ultrasound-guided biopsy of the right seminal vesicle and of a hypoechoic area documented by ultrasonography. 48 hours after the procedure, the patient had developed: cold sores, shortness of breath with dyspnea, and high fever (40°C). The patient was hospitalized, underwent an emergency CT which documented a right presacral and pararectal liquid mass (abscess). The patient underwent emergency laparotomy and drainage of the abscess. The lesion histological examination revealed a retroperitoneal schwannoma with inflammatory phenomena and hyperplasic lymphadenitis. The retroperitoneal schwannoma is a silent disease whose only clinical manifestation coincides with the compression of adjacent anatomical structures. In many cases, the symptoms, even if present, as in this case (ejaculatory pain with compression of the seminal vesicle), are non-specific, thus delaying diagnosis and the therapeutic approach.