THYMIC CARCINOMA METASTATIC TO THE ORBIT

PURPOSE: To report a case of small cell carcinoma of the thymus metast atic to the orbit. METHODS: At age 37 years, a man who had been previo usly diagnosed and treated for small cell carcinoma of the thymus was initially examined for vertical diplopia and left proptosis. Computed tomographic scan disclosed a soft tissue mass in the superior aspect o f the left orbit. A fine-needle aspiration biopsy of the mass was perf ormed and submitted for cytopathologic examination. RESULT: The cytopa thology and immunopathology disclosed malignant cells consistent with metastatic small cell thymic carcinoma. CONCLUSION: This is the first reported case of a primary thymus gland tumor metastatic to the orbit.