Multifocality related factors in papillary thyroid carcinoma

Area of Science:

• Oncology
• Surgical Pathology

Background:

• Papillary thyroid carcinoma (PTC) is the most common type of well-differentiated thyroid cancer.
• Multifocality in PTC is recognized as a negative prognostic indicator.

Purpose of the Study:

• To investigate the clinicopathological differences between multifocal and unifocal papillary thyroid carcinoma.
• To identify predictive factors for multifocal PTC.

Main Methods:

• Retrospective review of 777 thyroidectomy cases, including 305 with PTC.
• Patients were divided into Group 1 (multifocal PTC) and Group 2 (unifocal PTC).

Main Results:

• Multifocal PTC (Group 1) showed a higher incidence of the pathological mixed variant (p=0.005) and lymph node metastasis (LNM) (9.6% vs 3.5%, p=0.028).
• Micropapillary PTC rates were higher in unifocal cases (40.7% vs 28.4%, p=0.017).
• Tumor size, mixed-type pathology, and fine-needle aspiration biopsy (FNAB) results differed significantly between multifocal and unifocal micro PTC (p<0.05).

Conclusions:

• Multifocality is more prevalent in tumors ≥1 cm and mixed-type PTC.
• Lymph node metastasis is more frequent in multifocal PTC.
• Ultrasound-guided FNAB can predict micropapillary tumors, and mixed-type pathology predicts multifocality.