Orbital metastasis from medullary thyroid carcinoma

Area of Science:

• Ophthalmology
• Endocrinology
• Oncology

Background:

• Multiple endocrine neoplasia type 2A (MEN2A) is a rare genetic disorder.
• Medullary thyroid carcinoma (MTC) is a common manifestation of MEN2A.
• Orbital involvement in MTC is exceptionally rare.

Observation:

• A 46-year-old woman with MEN2A presented with unilateral proptosis and diplopia.
• Clinical and imaging findings suggested thyroid-associated orbitopathy.
• A progressive increase in the size of the left inferior rectus muscle was noted on CT scans.

Findings:

• Excisional biopsy confirmed metastasis of MTC to the left inferior rectus muscle.
• This represents a rare instance of MTC orbital metastasis.
• Unilateral proptosis necessitates investigation for intraorbital or intracranial disease.

Implications:

• Early detection of MTC metastasis is crucial for patient management.
• Surgical debulking can alleviate compressive symptoms and prevent damage to vital structures.
• Multidisciplinary care involving ophthalmology, oncology, and endocrinology is essential for optimizing treatment outcomes in metastatic MTC.