Proptosis of eye: an atypical presentation of prostatic malignancy

Orbital metastasis is a rare occurrence found only in about 3 - 10% of all prostate cancers. A 72 years male presented with proptosis of the left eye associated with pain, blurred vision and frequent headaches for the past 8 months. Past medical history had symptoms of bladder outflow obstruction for 3 years. MRI brain and orbit with contrast was consistent with a large soft tissue mass in the left frontal region. The mass was surgically excised in order to achieve palliation. Histopathology revealed poorly differentiated malignant neoplasm with immunohistochemistry favoring metastatic prostate carcinoma. Postoperative radiotherapy was administered with a palliative intent. CT scan identified an enlarged prostate with a nodular lesion, abdominal lymphadenopathy and soft tissue density lesion in the apical segment of left lung. Serum PSA level was 149 µg/L. Bone scan was also consistent with metastatic disease.