Orbital metastasis as a first indication of prostate cancer: a case report.

Prostatic carcinoma accounts for only 3.6% of orbital metastases encountered in clinical practice. We report the clinical presentation and response to treatment of a patient with metastatic prostatic carcinoma to the sella turcica. A 73-year-old man presented with a three-months history of progressive right proptosis associated with increasing diplopia in down-gaze and slightly decreased visual acuity. Gadolinium-MRI scans of the head revealed a left osteoblastic intrasellar mass, displacing the pituitary gland. Laboratory testing revealed a serum PSA level of 22 ng/ml. Transrectal ultrasound-guided biopsy revealed prostatic adenocarcinoma (Gleason score 4+3) in both lobes of the prostate. A bone scan was performed showing that the patient had multiple secondary bony lesions. Total androgen blockade was initiated. Moreover, he was referred for radiotherapy of this metastatic lesion to the sella turcica. The visual complaints regressed dramatically within the first month of the treatment. A follow-up MRI scan at 6 months showed almost complete involution of the orbital metastatic process. However the disease subsequently progressed and the patient died 22 months after diagnosis.