Rare Presentation of Follicular Thyroid Carcinoma with Retrosternal Goiter: A Case Report and Literature Review

Abstract

Follicular thyroid carcinoma (FTC) with retrosternal goiter is a rare clinical scenario, posing significant diagnostic and therapeutic challenges. These cases require detailed differentiation between intrathyroidal extension and distant metastasis. We present a 55-year-old female who presented with a longstanding neck and chest mass, initially noted in adolescence and previously operated on 20 years prior. Recent investigations were prompted by new-onset hypertension. Chest radiography revealed a persistent mediastinal mass, prompting referral for further evaluation. CT-guided core biopsy confirmed retrosternal goiter, and FNAB indicated a follicular neoplasm. Physical examination showed a 2x3 cm immobile, firm, and tender mass at the xiphoid region. Laboratory tests only demonstrated elevated TSH levels. Thoracic and cervical CT with contrast, revealed a heterogeneous, solid mass with necrotic areas in the anterior mediastinum, adherent to the aortic arch and compressing both upper lung lobes, along with multiple peritumoral lymph nodes and left lower lobe pneumonia. The thyroid gland displayed a lobulated mass extending into the thoracic inlet and retrosternal region. The patient underwent a combined pro-thyroidectomy retrosternal via sternotomy and completion thyroidectomy with central compartment clearance. Postoperative recovery was uneventful, and histopathological examination confirmed the diagnosis of follicular thyroid carcinoma. Follow-up imaging showed no residual tumor or further metastasis. This case highlights the diagnostic complexity of FTC with retrosternal extension, necessitating a multidisciplinary approach for accurate diagnosis and effective surgical management. Our literature review underscores the rarity of such presentations and emphasizes the need for heightened clinical vigilance in similar cases.