Multifocality and bilaterality of papillary thyroid microcarcinoma

Area of Science:

• Endocrinology
• Oncology
• Surgical Pathology

Background:

• Papillary thyroid carcinomas (PTCs) commonly present as multifocal disease.
• Multifocal tumors are frequently missed during preoperative radiologic evaluations, potentially leading to residual disease.
• Papillary thyroid microcarcinomas (PTMCs) are defined as PTCs measuring ≤1 cm.

Purpose of the Study:

• To investigate the incidence of multifocal PTMCs.
• To assess the diagnostic accuracy of preoperative radiologic evaluations for multifocal PTMCs.
• To identify predictive factors for multifocal and bilateral PTMCs.

Main Methods:

• Retrospective review of medical records, pathology reports, and radiological reports.
• Analysis of data from 277 patients who underwent total thyroidectomy for PTMC.
• Statistical analysis to determine incidence, diagnostic accuracy, and predictive factors.

Main Results:

• Multifocal PTMCs were identified in 36.1% of patients.
• Additional tumor foci were significantly smaller than primary tumors.
• Preoperative sonography sensitivity for multifocal and bilateral tumors was low (42.7% and 49.0%, respectively).
• Nodular hyperplasia was the only significant predictor of multifocal PTMCs.

Conclusions:

• The incidence of multifocal PTMCs is substantial.
• Undetected, small additional tumor foci pose a challenge for preoperative diagnosis.
• Multifocal PTMCs are associated with a high risk of bilateral involvement, necessitating tailored surgical or follow-up strategies.