Clinicopathology of Papillary Thyroid Microcarcinomas

Abstract

Objective: The widespread use of ultrasonography is the main reason for the increase in the detection of papillary thyroid microcarcinomas (PTMs). We evaluated the clinicopathological features of cases diagnosed with PTM in our clinic.

Materials and Methods: In this retrospective study, 354 cases were evaluated. Cytological diagnoses were classified using the 2017 Bethesda System. Statistical analyses were made using IBM SPSS Statistics v. 22. Comparisons between the groups were analyzed with the chi-Square test, Fisher exact chi-square test, Student’s t-test, and Mann-Whitney U test.

Results: Forty-eight percent of the cases were diagnosed with PTM and 47.1% with incidental papillary thyroid microcarcinoma (IPTM). The rate of female patients was higher in the IPTM group than in the papillary thyroid carcinoma (PTC) group, and the difference was statistically significant (p<0.001). The co-occurrence of chronic lymphocytic thyroiditis (CLT) was higher in the PTM cases than in the PTC group (41.2% and 36.9%, respectively). The mean TSH value was higher in the PTM group than in the PTC group. Capsular invasion was seen at a higher rate in the PTC group than in the PTM group (p<0.001).

Conclusion: In our study, we observed lower TSH values in cases with IPTM compared to those with PTC at a younger age and in the female gender. We consider that due to the small tumor diameter of IPTMs, their metastasis ability is lower, and therefore they have a good prognosis.