Endocrine Abstracts

Introduction: Thyroid cancer is the most common endocrine neoplasia, with papillary thyroid carcinoma (PTC) being the subtype that represents 75 - 80% of cases; with an indolent character and a 10-year survival rate greater than 90%. Vascular infiltration is very rare in this type of tumors, which usually spread through the lymphatic route. The treatment of choice continues to be surgery with adjuvant radioiodine based on the risk stratification of recurrence and radiotherapy in very selected cases.

Case Presentation: We present the case of a 78-year-old male patient with a grade III goiter at the expense of the left thyroid lobe with an intrathoracic component and Bethesda IV FNAC, anticoagulated for left jugular vein thrombosis. Presented in a multidisciplinary committee, a total thyroidectomy was decided. During surgery, a 10 cm locally advanced tumor mass was observed that infiltrated the esophagus and was closely adhered to the internal jugular vein. During the process, there is a loss of signal from the recurrent laryngeal nerve (RLN), so the total thyroidectomy is not completed while awaiting the definitive pathological result. The final pathology confirmed infiltrative follicular variant papillary carcinoma with extrathyroidal extension and vascular and lymphatic infiltration (pT3b). Subsequent surgery involved a totalizing right lobectomy and adjuvant 1131 treatment. Follow-up showed increased thyroglobulin, cervical remnants with a left internal jugular vein tumor thrombus, and suspicious lymph nodes in the left compartment ll. An exploratory cervicotomy revealed a large tumor thrombus affecting the entire cervical extension of the left internal jugular vein, requiring resection with spinal nerve preservation. Intraoperatively, a tumor mass infiltrating the pharyngoesophageal junction was observed, necessitating debulking surgery, leaving a small tumor due to the risk of pharyngeal fistula, excision of pathological lymphadenopathy at the level of compartment II. Subsequently, the tumor bed was marked with clips for adjuvant radiotherapy.

Discussion: Surgery remains crucial in managing recurrent thyroid cases unresponsive to radioactive iodine treatment. Locally advanced thyroid neoplasms are rare, requiring individualized management in clinical committees and specialized centers with experienced endocrine surgeons.