The differences between unilateral multifocality and bilateral multifocality in papillary thyroid carcinoma: a...

Area of Science:

• Endocrinology
• Oncology
• Pathology

Background:

• Papillary thyroid carcinoma (PTC) multifocality presents as unilateral (UMPTC) or bilateral (BMPTC).
• Understanding the distinct clinical behaviors of UMPTC and BMPTC is crucial for patient management.

Purpose of the Study:

• To investigate and compare clinicopathological differences between unilateral multifocal PTC (UMPTC) and bilateral multifocal PTC (BMPTC).

Main Methods:

• Retrospective analysis of 503 patients who underwent complete thyroidectomy for PTC.
• Patients were categorized into UMPTC and BMPTC groups, with BMPTC further classified into N1-BMPTC and N2-BMPTC subgroups based on lesion distribution.

Main Results:

• BMPTC and its subgroups (N1-BMPTC, N2-BMPTC) showed larger maximum tumor diameters than UMPTC.
• The N1-BMPTC group had a higher recurrence rate and lower disease-free survival (DFS) compared to UMPTC.
• No significant differences were observed in gender, age, BMI, Hashimoto's thyroiditis, nodules, capsular invasion, extrathyroidal extension, or AJCC staging between groups.

Conclusions:

• The N1-BMPTC subgroup, defined by specific lesion distribution across both thyroid lobes, is associated with increased lymph node metastasis and tumor recurrence.
• Patients with N1-BMPTCs face a higher risk of recurrence than those with other forms of multifocal PTC.