Domínguez José Miguel, Baudrand René, Arteaga Eugenio, Campusano Claudia, González Gilberto, Mosso Lorena, Cavada Gabriel, Cruz Francisco, Torres Javiera, Solar Antonieta, Arias Tatiana, Pizarro Alejandra, Gómez Marcelo, Fardella Carlos
Departamento de Endocrinología, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile.
Rev Med Chil. 2009 Aug;137(8):1031-6. Epub 2009 Nov 4.
Thyroid nodules are common and associated to a low risk of malignancy. Their clinical assessment usually includes a fine needle aspiration biopsy (FNAB).
To identify ultrasonographic characteristics associated to papillary thyroid carcinoma (PTC) and generate a score that predicts the risk of PTC.
Retrospective review of all fine needle aspiration biopsies of the thyroid performed in a lapse of two years. Biopsies that were conclusive for PTC were selected and compared with an equal amount of randomly selected biopsies that disclosed a benign diagnosis.
One hundred twenty two biopsies of a total of 1,498 were conclusive for PTC. Univariate analysis showed associations with PTC for the presence of micro-calcifications (Odds ratio (OR) 49.2: 95% confidence intervals (CI) 18.7-140.9), solid predominance (OR 25.1; 95% CI 6-220), hypoechogenicity (OR 23.5, 95% CI 6.5-122.6), irregular borders (OR 17, 95% CI 7.2-42.9), lymph node involvement (OR 12.3, 95% CI2.7-112), central vascularization (OR 12.2, 95% CI 4.8-33.3), local invasion and hyperechogenicity (OR 0.2; CI 95% CI 0.03-0.6). Multivariate analysis disclosed microcalcifications (OR 28.1; CI 95% 8.9-89), hypoechogenicity (OR 9.4; 95% CI 1.5-59.5) and irregular borders (OR 4.7; CI 95% 1.5-15) as the variables independently associated with the presence of PTC. The prevalence of PTC in the presence of the three variables was 97.6% (Likelihood ratio (LR) 45) and 5.4% in their absence (LR 0.06).
This scale predicts the presence or absence of PTC using simple ultrasound characteristics.
