Biological Behavior Of Papillary Thyroid Carcinoma Research Articles

Multifocality increases the risk of central compartment lymph node metastasis but is not related to the risk of recurrence and death in papillary thyroid carcinoma.

Multifocality is a distinctive feature of papillary thyroid carcinoma (PTC); however, the biological behavior of PTC and its optimal management strategy remain unclear. The aim of this study was to analyze the clinical features and prognostic differences of multifocal papillary carcinoma and to guide the precise treatment of multifocal papillary carcinoma. The medical records of 1,139 patients with PTC who had undergone total or hemi-thyroidectomy between April and October 2013 at the Tianjin Medical University Cancer Institute and Hospital were reviewed. The number of central compartment lymph node metastasis (LNM), as well as the size, number, and laterality of each tumor focus, along with other possible risk factors were recorded. Patients were followed up until May 2024. According to univariate and multivariable analyses, PTC, multifocality, and male sex were risk factors for level VI LNM. Moreover, the central compartment LNM rate increased proportionally with the number of foci. The LNM rates for patients with unilateral papillary thyroid microcarcinoma (PTMC) having one, two, three, and four foci were 27.8% (146/525), 37.3% (55/142), 40% (14/35), and 57.1% (4/7), respectively; conversely, the LNM rates for patients with bilateral PTC having two, three, four, five, and six foci were 50% (15/30), 62.5% (15/24), 70% (7/10), 83.3% (5/6), and 100% (2/2), respectively. Notably, the LNM rates were comparable for multifocal PTMCs (largest tumor diameter: 6-10 mm) and unilateral unifocal PTCs [44.0% (55/125) vs. 60.8% (59/97); P=0.43 (0.42-0.93)]. Meanwhile, the survival rates and risk of recurrence were comparable for multifocal and unifocal PTCs. Multifocality is indicative of a heightened risk of LNM in PTC but does not increase the risk of recurrence or mortality. Multifocal PTMCs with a tumor diameter of 6-10 mm should undergo thorough preoperative evaluation of the regional lymph nodes as they have a higher risk of developing LNM.

Relationship of biochemically persistent disease and thyroglobulin-doubling time to age at surgery in patients with papillary thyroid carcinoma

In patients with papillary thyroid carcinoma (PTC), detectable serum thyroglobulin (Tg) after total thyroidectomy implies biochemically persistent disease (BPD). We reported that the thyroglobulin-doubling time (Tg-DT) was a potent prognostic indicator in patients with BPD. To identify factors that are related to BPD and Tg-DT, we performed new analyses on the data gathered in our previous study. Using the data of 426 patients with PTC in whom the Tg-DT was computed after total thyroidectomy, multivariate logistic analyses for BPD and Tg-DT were performed. Postoperatively, 142 (33%) patients had BPD. The percentages of BPD patients were significantly higher among the young (<40 years) and elderly (≥60 years) patients compared to the middle-aged patients (41%, 41%, and 27%, respectively). Multivariate analysis showed that cN1b, tumor size ≥4 cm, and Ex2 were significantly associated with BPD. The percentage of patients with Tg-DT <2 years among the BPD patients increased with age: 6% in the young, 15% in the middle-aged, and 47% in the elderly patients. Multivariate analysis of the BPD patients revealed that Tg-DT was associated only with the age at surgery. The current analyses indicate that BPD is significantly correlated with the extent of disease status and that Tg-DT correlates only with patient age at surgery. Although our results clearly indicate that the biological behavior of PTC is age-related, the underlying reason for this remains to be established.