Lymph node metastases in pediatric medullary thyroid carcinoma

Area of Science:

• Oncology
• Pediatric Endocrinology
• Surgical Oncology

Background:

• Pediatric medullary thyroid carcinoma (MTC) is predominantly hereditary, unlike adult MTC.
• Genetic drivers of pediatric MTC differ, but clinicopathologic distinctions remain unclear.
• Understanding these differences is crucial for determining appropriate treatment, such as elective neck dissection.

Purpose of the Study:

• To compare clinicopathologic features and outcomes of pediatric MTC with adult MTC.
• To identify risk factors for nodal metastases in pediatric MTC.
• To inform the selection of pediatric MTC patients who may benefit from elective neck dissection.

Main Methods:

• Retrospective analysis of the National Cancer Database (2004-2016).
• Inclusion of patients aged 0-19 diagnosed with medullary thyroid carcinoma.
• Comparison of clinicopathologic factors, treatments, and outcomes between pediatric and adult MTC cohorts.

Main Results:

• Pediatric MTC patients (n=125) had smaller tumors and lower nodal metastasis rates than adults (n=5086).
• Pediatric MTC exhibited higher rates of multifocal tumors (59.3% vs 29.9%).
• Older children (6-19 years) had a considerable risk of occult nodal metastases (21.4%), similar to adults (25.8%).

Conclusions:

• Pediatric MTC generally has lower lymph node metastasis rates than adult MTC.
• Youngest children (<5 years) have a low risk of nodal disease.
• Older children (6-19 years) are at significant risk for occult nodal metastases, warranting consideration for elective neck dissection.