Carcinoma papilar difuso de tiroides: Microcalcificaciones fuera del nodulo tiroideo

Abstract

Abstract INTRODUCTION: The incidence of thyroid papillary cancer (PTC) has increased from 1975 to 2015. Ultrasound is effective for predicting thyroid malignancy based on published criteria. All of these criteria focus on thyroid nodules but also 2% of the cases may appear as diffuse punctuate echogenic foci without an identifiable nodule. CASE: A 17-year-old female with a 3-month history of a palpable mass on the right anterior side of the neck without any further symptoms. Neck ultrasound revealed multiple punctuate echogenic foci scattered along the thyroid parenchyma with a 6 mm nodule TI-RADS 5 on the left lobe, lymph nodes with cystic and solid components, loss of echogenic hilum and punctuate echogenic foci. The patient underwent a total thyroidectomy with bilateral lymphadenectomy. The pathology report revealed diffuse distribution of papillary cancer with a nodule on the left lobe and metastatic disease on the lymph nodes. DISCUSSION: Microcalcifications are highly suggestive of PTC. Punctuate echogenic foci correlate in pathology with a form of dystrophic calcifications, called Psammoma bodies, which are deposited in nonviable tissue. Chronic thyroiditis may also present dystrophic calcifications. Thus, a normal thyroid parenchyma with microcalcifications should encourage the radiologist perform a fine-needle aspiration biopsy (FNAB). Recent studies suggest that lobectomy is a viable option and should be pursued in the setting of localized PTC (<2cm). A lobectomy should not be performed in patients with diffuse microcalcifications since it would result in an unfavorable outcome. CONCLUSIONS: Diffuse microcalcifications should immediately make the radiologist to suspect diffuse PTC as a first diagnostic option. Key words: Thyroid papillary cancer (PTC), Ultrasound (US), Psammoma, Chronic thyroiditis