Comparison of Papillary Thyroid Microcarcinoma and Carcinoma - Original Article

Abstract
Objective: The aim of this study is to evaluate some preoperative and postoperative clinical and histopathological characteristics of patients with papillary thyroid microcarcinoma (PTMC). We also compared these features with papillary thyroid carcinoma greater than 1 cm (PTC). 
Materials and Methods: We reviewed the clinical data of 224 patients who were diagnosed and treated for papillary thyroid carcinoma. Both the preoperative and postoperative features of patients were assessed. There were 132 patients with PTMC and 92 patients with PTC.
Results: The mean age and the incidence of hyperthyroidism were higher in patients with PTMC compared to patients with PTC. There were also a higher number of patients operated for benign lesions in PTMC group. In histopathologic examination, mean tumor diameter was 5.8±2.8 mm in PTMC patients. Although, we found capsular invasion in 17.4%, vascular invasion in 1.5%, extrathyroidal extension in 3%, lymph node involvement in 3.8% and multifocality in 18.9% of PTMC patients, these percentages were significantly lower than in PTC patients. Tumor was detected incidentally in 37.1% and nonincidentally in 62.9% of PTMC patients. No significant difference was present between incidental and nonincidental PTMC in terms of age, sex, and histopathological findings. Anyway, tumor diameter was greater in nonincidental PTMC compared to incidental PTMC.
Conclusions: Histopathological features of incidental and nonincidental PTMC did not differ, while there was a significant difference between PTMC and PTC in terms of tumoral characteristics. However, particularly multifocality and capsular invasion were present in a considerable number of PTMC patients. We suggest that patients with PTMC should also be managed like patients with PTC.