Background and aim: Papillary thyroid carcinomas (PTCs) with a diameter <1 cm are referred to as papillary microcarcinomas (PTMCs). They are being diagnosed with increasing frequency. Within this type of tumour some clinical and histological characteristics with prognostic and therapeutic impact have been proposed. In the present study we describe the clinical and pathological presentation of PTMCs and compare them with papillary thyroid carcinomas of larger size.
Methods: Clinical and histopathological variables, such as gender, age, multifocality, lymph node metastases, and mode of diagnosis were studied in 152 PTCs, including 74 PTMCs and 78 PTCs of larger size.
Results: PTMCs were associated with less multifocality (P=0.046) and bilaterality (P=0.003), fewer lymphadenectomies (P<0.001), and a decreased rate of nonincidental tumours (P<0.001). Patients with a low aggressive profile were significantly older that the remaining patients (54±13.7 vs 45.8±13.1 years; P=0.001). This low aggressive profile was observed in 28 (36.8%) of 76 patients older than 45 years and only in 12 (17.9%) of 67 patients younger than 45 years (P=0.006).
Conclusions: PTMCs show significant differences in the form of presentation, though, a subset of PTMCs exhibits aggressive features that may be associated with signs of poor prognosis. Furthermore, it is possible that classical risk factors well validated in PTCs, such as age, must be cautiously interpreted in the current increasing subgroup of PTMCs.
Prague, Czech Republic
24 - 28 Apr 2010
European Society of Endocrinology