Outcomes and Pathological Features of Total Thyroidectomy in Patients with Multifocal Papillary Thyroid Carcinoma

Aim: The incidence of thyroid cancer has increased dramatically in recent decades. Multifocality is considered a poor prognostic factor for papillary thyroid carcinoma (PTC). Patients with multifocal PTC (MPTC) are at high risk for local recurrence, as well as lymphatic and distal metastases. This study examined the features and outcomes of MPTC. Material and Methods: This retrospective study was conducted on 300 patients with PTC. Patients were classified into a multifocal group and a unifocal group. The pathological features of the PTC and the patients' outcomes were analyzed and compared. Results: The multifocal group included 146 patients (48.7%), while the unifocal group included 154 patients (51.3%). The occurrence of multifocality was higher in females than in males (Odds ratio, OR: 2.37, 95% confidence interval, CI: 1.20-4.67, p=0.015). Tumor size of >1 cm in the multifocal group was larger than in the unifocal group (2.5 and 2.2 cm, respectively, p=0.021). Moreover, in multifocal group higher moderate risk of recurrence was detected than in the unifocal group (OR: 1.63, 95% CI: 1.01-2.60, p=0.044). At follow-up after treatment, MPTC patients had higher lymph node metastasis (OR: 2.89, 95% CI: 1.23-6.80, p=0.014). In addition, significantly higher thyroglobulin plasma levels (p=0.026) and disease recurrence (OR: 2.41, 95% CI: 1.05-5.52, p=0.037) were found in the multifocal group compared to the unifocal group. Conclusion: Patients with MPTC had a higher risk of disease recurrence, and multifocality was concluded to be an independent prognostic factor for overall disease recurrence.