Rare Onset of Ocular Choroidal and Pituitary Metastases From Differentiated Thyroid Cancer
Posted: Thursday, April 1, 2021
Heather Lochnan, MD, of The Ottawa Hospital, Canada, and colleagues presented reportedly the first known case of simultaneous manifestation of ocular choroidal and pituitary metastases from differentiated thyroid carcinoma in the Journal of Clinical and Translational Endocrinology: Case Reports. This occurred in a patient who previously had undergone total thyroidectomy but demonstrated abnormally high thyroid-stimulating hormone (TSH) stimulated thyroglobulin levels 4 years after treatment.
A 58-year-old man presented with TSH stimulated thyroglobulin levels of 10.8 pmol/L. The goal level for patients who underwent thyroidectomy and ablation was undetectable, with concerning levels reaching 2.0 pmol/L. Scans did not reveal localized disease. A year later, these levels rose to 85.4 pmol/L, with positive CT and PET scans. Mediastinal lymph nodes metastasis was diagnosed and a second dose of 202 mCi radioiodine ablation therapy brought the stimulated and unstimulated levels down to 12.1 pmol/L and 9.7 pmol/L after 4 months, respectively.
Likely metastatic mediastinal and cervical lymph nodes were removed when the patient’s TSH unstimulated thyroglobulin level reached 22.71 pmol/L. Classic-type papillary thyroid mediastinal metastasis and a component of poorly differentiated thyroid carcinoma were identified via surgical report. The patient declined external-beam radiation therapy.
The patient’s unstimulated thyroglobulin level did not cease to rise. A CT scan revealed a pulmonary nodule, and ultrasound-guided fine-needle aspiration confirmed its malignancy. The patient underwent left-side and right-side neck dissection of the cervical lymph node and a third round of 210 mCi radioiodine ablation therapy, yet unstimulated thyroglobulin levels continued to rise.
FDG-avid hepatic and lymph node metastases were found, with multiple bilateral lung nodules. The patient experienced headaches and visual changes when the thyroglobulin levels reached 1,578 pmol/L, confirming a left retinal abnormality compatible with intraocular metastasis. A brain MRI showed a left ocular globe–enhancing lesion, and the patient was started on lenvatinib. Months later, CT and MRI demonstrated shrinkage of all nodules in response to lenvatinib treatment.
Disclosure: The study authors reported no conflicts of interest.