Evaluation of papillary thryoid carcinoma and its variants: multifocality in thyroid lobectomy and completion thyroidectomy - a single tertiary center retrospective study

Aims. The American Thyroid Association (ATA) updated guidelines for the treatment of thyroid cancer, leading to a less aggressive approach depending on clinical-pathological features. As a result, the possibility to perform lobectomy versus total thyroidectomy has significantly increased. The majority of thyroid cancers are indolent with an excellent prognosis, while only 15% of patients with well-differentiated carcinoma, including papillary thyroid carcinoma (PTC), have locally advanced thyroid cancer (LATC) at diagnosis. We reviewed our practice in treating thyroid carcinoma over the last decade. Methods. From January 2010 to December 2020, 1057 patients with uninodular benign and malignant thyroid lesions were reviewed. Results. Among these cases, 77% were women with a median age of 49.3 years. The series involved 307 malignant diagnoses (29.05%) including 196 (61.6%) classic PTC and 38 (12%) aggressive variants of PTC, mostly tall cell variant (30 cases, 9.4%). Among malignant cases, multifocality was microscopically documented in 84 cases (26.4%). Using the ATA distribution of risk, there were 239 cases in the low risk and 68 in the intermediate risk categories. Second surgery was assessed in a total of 150 cases, showing 42 cases with additional thyroid cancer foci in the other lobe (26 single vs 16 multiple foci). Ten cases had metastatic perithyroidal lymph nodes. Conclusion. Our data could be the basis for performing a longitudinal study in order to establish which risk factors can predict bilateral involvement and to suggest a tailored surgical approach.