Medullary thyroid carcinoma. Genetic screening and prophylactic thyroidectomies

Area of Science:

• Endocrinology
• Oncology
• Genetics

Background:

• Medullary thyroid cancer (MTC) is a rare neuroendocrine tumor originating from C-cells.
• Calcitonin (TC) and CEA are key bioactive substances secreted by MTC, with TC serving as a crucial tumor marker.
• MTC can be sporadic or hereditary, linked to specific genetic mutations.

Purpose of the Study:

• To highlight the role of calcitonin (TC) as a tumor marker for early diagnosis, patient follow-up, and treatment evaluation in MTC.
• To emphasize the utility of the calcium/pentagastrin stimulation test for accurate TC determination and biochemical family screening.
• To underscore the importance of genetic screening for RET proto-oncogene mutations in hereditary MTC syndromes (MEN 2A, MEN 2B, FMCT).

Main Methods:

• Utilizing calcitonin (TC) and CEA as biomarkers for MTC diagnosis and monitoring.
• Employing calcium/pentagastrin stimulation tests for enhanced TC assessment and family screening.
• Conducting genetic screening for RET proto-oncogene mutations to identify individuals at high risk for MTC.

Main Results:

• Calcitonin (TC) is an effective marker for early MTC diagnosis, patient monitoring, and treatment assessment.
• Genetic screening identifies RET mutations, predicting a high likelihood (95% penetrance) of MTC development in affected individuals.
• Preventive total thyroidectomy (TT) with or without central neck dissection (CND) is recommended for individuals with high-risk RET mutations.

Conclusions:

• Early detection and intervention, including genetic screening and prophylactic surgery, are critical for managing MTC.
• Surgical treatment offers the potential for cure in C-cell hyperplasia and early-stage MTC.
• Prophylactic thyroid surgery prevents MTC but does not prevent other associated MEN 2 syndromes like pheochromocytoma or hyperparathyroidism.