Choroidal Metastasis from Follicular Cell Thyroid Carcinoma Masquerading as Circumscribed Choroidal Haemangioma

Choroidal metastases from follicular thyroid carcinoma are uncommon and usually present as an amelanotic lesion against a background of known systemic disease. We present the case of a 56-year-old woman with a thyroid metastatic focus with unusual clinical presentation, systemic involvement, and early response to systemic treatment. A review of the literature accompanies this case presentation. 1. Case Presentation A 56-year-old lady was referred to the Ocular Oncology Service with a seven-year history of deteriorating visual acuity in the left eye. Patient had a 15-year history of sarcoidosis associated with recurrent uveitis. Best-corrected visual acuity was at 6/36？OS 6/6？OD. At presentation there was no active uveitis. Posterior segment examination revealed an elevated lesion inferotemporally to the macula of the left eye measuring 6.5 × 6.8？mm that was pale orange in colour and difficult to discern clinically from the surrounding retina (Figure 1(a)). A fundus fluorescein angiogram indicated early hyperfluorescence. B-scan ultrasound demonstrated a dome-shaped lesion with high internal reflectivity measuring 2.7？mm in elevation. A Doppler B-scan ultrasound indicated the presence of internal blood flow. Clinical appearance at presentation was typical of a circumscribed choroidal haemangioma although a metastatic deposit remained within the differential diagnosis. No ocular treatment was performed but review was arranged in 3 months pending ongoing investigations for a thyroid gland mass discovered on a routine CT scan of the neck and chest. Figure 1: (a) Pale orange lesion involving the macula and extending inferotemporally before treatment. Clinical appearance is consistent with a circumscribed choroidal haemangioma. (b) After four months a pale, fibrotic scar has developed in the site of the original lesion following treatment. Thyroid gland biopsy proved the mass was a follicular cell carcinoma of the thyroid and systemic staging revealed stage 4 disease due to the presence of bone metastases in the left iliac crest and in the right femur, the latter causing a pathologic fracture. Patient underwent total thyroidectomy. Excision was incomplete and patient received 2 initial sessions of adjuvant treatment of radioactive iodine (131I) therapy (4.9 and 5.8？GBq, resp.). The pathologic fracture was managed with internal fixation and adjuvant external beam radiotherapy (EBRT) with 35？Gy at 15 sessions in the iliac crest and 20？Gy in the femur. Following radioactive treatment of the thyroid gland the visual acuity reduced to counting fingers. Fundus