Is multifocality a risk factor in low-risk papillary thyroid cancer?

Area of Science:

• Endocrinology
• Oncology
• Pathology

Background:

• Multifocality is a frequent occurrence in papillary thyroid cancer (PTC), with reported rates varying widely.
• The factors influencing intrathyroidal spread and the prognostic significance of multifocal PTC remain incompletely understood.
• This study investigates the characteristics and clinical outcomes associated with multifocal PTC.

Purpose of the Study:

• To identify histopathological and clinical features associated with multifocal papillary thyroid cancer.
• To assess the impact of multifocality on the long-term clinical outcome of PTC patients.
• To clarify the relationship between multifocality, patient demographics, tumor characteristics, and lymph node metastasis.

Main Methods:

• Analysis of a consecutive series of 2814 PTC patients who underwent total thyroidectomy.
• Patients were categorized into unifocal and multifocal groups.
• Follow-up included clinical assessment, biochemical markers (thyroglobulin, anti-thyroglobulin antibodies), neck ultrasonography, and radioiodine therapy when indicated.

Main Results:

• Multifocal PTC was more prevalent in older patients (median age 46.4 vs. 44.5 years) and had a lower female-to-male ratio (3.7:1 vs. 4.7:1).
• Multifocality was less common in larger tumors (T2) but more frequent in cases with N1b lymph node metastasis.
• The overall clinical outcome was similar between unifocal and multifocal PTC groups, with high rates of cure in both.

Conclusions:

• Multifocality in papillary thyroid cancer is associated with older age, male gender, smaller tumor size, and N1b lymph node involvement.
• Despite these associations, multifocality itself was not found to be an independent predictor of worse clinical outcomes in this cohort.
• These findings suggest that multifocality should be considered in the context of other prognostic factors in PTC management.