[Choroidal metastasis from follicular thyroid carcinoma: a rare case]

Choroidal metastases are, with melanoma, the most frequent malignant eye neoplasms. Breast carcinoma for women and lung carcinoma for men most commonly metastasize to the eye. We report a rare case of choroidal metastasis from follicular thyroid carcinoma.

A 75-year-old man, with metastatic follicular thyroid carcinoma, presented a decline in visual acuity of the left eye lasting one month. The best corrected visual acuity was 3/10 in his left eye. Biomicroscopic examination of the anterior segment did not reveal anything abnormal. Funduscopic examination showed an amelanotic choroidal mass located at the posterior pole with serous retinal detachment. Tomoscintigraphy with computed tomography confirmed the thyroid origin by uptake of radioiodine in the choroidal mass. External radiotherapy was then proposed.

Although it is exceptional, diagnosis of choroidal metastases should be considered in any decline in visual acuity in patients with thyroid cancer. The treatment is difficult because metastases from thyroid cancer are very poorly sensitive to radiotherapy and chemotherapy.