[Predictive malignancy factors in thyroid nodular disease]

Nodular thyroid pathology is frequent and remains a controversial issue when it comes to establishing an ideal endocrine surgical strategy. We studied clinical and complementary data predictive of malignancy using a large retrospective analysis of 366 cases operated for nodular pathology of the thyroid gland between January 1995 and December 1997 in our Head and Neck Surgery Unit of the Pasteur Hospital in Nice, France. The incidence of malignancy was 12.8% with the usual histologic findings (83% of well-differentiated tumors: 70% papillary, 13% vesicular, 9% medullar, 6% oncocytic and 2% anaplastic). Statistical analysis did not conclude on the predictive value of several items in terms of their relationship to high risk of malignancy (p > 0.05): size of nodules, signs of local compression, biological findings, presence of calcifications, mixed ultrasound aspect, no hypoechogenic halo, scintigraphic aspect. This retrospective work did however identify items predictive of malignancy when appearing in patients with nodular thyroid disease: male sex (odds ratio 2.4; 95%CI [1.17-4.88]; p=0.13), age (less than 40 yr or more than 70yr) (p=0.003), hard nodule consistency (odds ratio 7.40; 95%CI [3.99-13.52], p<0.001), invasion of lymphatic nodes noted prior to surgery (p=0.031), hyperechogenicity on ultrasound exam (p=0.013). We were able to confirm the highly negative predictive value (92%) of fine needle aspiration, emphasizing its value in endocrine thyroid nodular disease diagnosis.