Multifocality related factors in papillary thyroid carcinoma

Abstract

Papillary thyroid carcinoma (PTC) is the main type of the well-differentiated thyroid carcinomas. Multifocality is regarded as a poor prognostic factor for PTC. Documents of 777 patients who underwent thyroidectomy were reviewed retrospectively. A total of 305 PTC patients were included. Patients with multifocal PTC were included in Group 1, and patients with unifocal PTC were included in Group 2. There were 165 patients (54.0%) in Group 1 and 140 patients (46%) in Group 2. The pathological mixed variant of PTC was significantly higher in Group 1 (p=0,005). Lymph node metastasis (LNM) was detected at 9.6% and 3.5% in Group 1 and Group 2, respectively (p=0,028). Micro PTC rates were 28.4% and 40.7% in Group 1 and Group 2, respectively (p=0,017). Tumor size and pathologically mixed-type and fine-needle aspiration biopsy (FNAB) results were significantly different between multifocal and unifocal Micro PTC (p<0.05). Multifocality is more frequent in patients with tumors ≥1cm and mixed-type tumors. LNM is found more often in multifocal tumors. The presence of micropapillary tumors can be predicted preoperatively by ultrasound-guided FNAB. Mixed-type pathology is also a predictive factor for multifocality.