Sexual dimorphism in medullary thyroid cancer aggressiveness

Area of Science:

• Endocrinology
• Oncology
• Cancer Biology

Background:

• Medullary thyroid cancer (MTC) exhibits a female predominance, yet men often present with more aggressive disease.
• Understanding sex-specific differences in MTC is crucial for targeted treatment and prognosis.

Purpose of the Study:

• To quantify sex-specific differences in medullary thyroid cancer (MTC) spread.
• To analyze these differences in relation to primary tumor size.

Main Methods:

• Retrospective analysis of 565 patients with unilateral solitary MTC undergoing initial neck surgery.
• Stratification by sex and tumor size to assess differences in calcitonin levels, extrathyroid extension, node metastasis, and biochemical cure rates.

Main Results:

• Men with MTC had higher calcitonin levels, more frequent extrathyroid extension and node metastasis, and fewer achieved biochemical cure compared to women.
• Sex disparities were evident in tumors 5.1-40 mm but diminished in larger tumors (>40 mm).
• Node metastasis showed the strongest sex disparity (24.0% overall difference).

Conclusions:

• The male predominance in MTC aggressiveness is likely biologically driven.
• Further research into the biological mechanisms underlying sex differences in MTC is warranted.