An uncommon case of coexistence of thyrolipoma and angioinvasive follicular thyroid carcinoma with a background of lymphocytic thyroiditis: Clinical case report.

INTRODUCTION AND

IMPORTANCE

Angioinvasive type of FTC, characterized by vascular invasion with poor prognosis. Thyrolipoma may manifest as a single thyroid lesion or, in conjunction with multiple thyroid lesions. Approximately 5 to 10 % of thyroid nodules are malignant. The coexistence of angioinvasive FTC with a thyrolipoma, further complicates the clinical scenario and may affect the diagnosis of such aggressive disease.

CASE PRESENTATION: We report a case of a 43-year-old female who presented with thyroid enlargement. Imaging revealed a multinodular goitre, and fine needle aspiration cytology from the right thyroid nodule was suspicious for follicular neoplasm (Bethesda IV). The patient underwent total thyroidectomy, and the histopathological studies confirmed the presence of right thyroid lobe angioinvasive FTC with three foci of vascular invasion with background of lymphocytic Thyroiditis (LT). Interestingly, an incidental finding of thyrolipoma was identified in the left lobe.

CLINICAL DISCUSSION: Vascular invasion is a known indicator of aggressive diseases and a strong predictor of distant metastasis in FTC, especially when it involves multiple locations. Recurrence rates are highly correlated with the degree of vascular invasion. Thyrolipoma can happen alongside malignant nodules from follicular or papillary thyroid tumours. LT is thought to increase the risk of papillary thyroid tumours and thyroid lymphoma. <5 % of thyroid cancers in LT are FTC.

CONCLUSIONS

This case presents a rare combination of thyrolipoma, angioinvasive FTC and LT that were first to be appraised in the literature. Diagnosis hinges on postoperative histopathology, and management must focus on the aggressive FTC component.