Papillary thyroid carcinoma presenting as a functioning thyroid nodule: report of 2 rare cases

Area of Science:

• Endocrinology
• Oncology
• Surgical Pathology

Background:

• Autonomously functioning thyroid nodules (AFTNs) are typically benign, while papillary thyroid carcinomas (PTCs) are usually non-functioning.
• Graves' disease (GD) is the leading cause of hyperthyroidism (HD).
• The simultaneous occurrence of HD, AFTNs, and PTC is exceptionally rare in clinical practice.

Observation:

• Two middle-aged women presented with preoperative diagnoses of HD and AFTNs, with one also diagnosed with PTC.
• Histopathological examination revealed coexisting PTCs and either atypical Marine-Lenhart syndrome or toxic nodular goiter.
• The cases underscore the diagnostic challenges in differentiating benign from malignant thyroid conditions.

Findings:

• Histology confirmed the presence of PTC alongside GD and/or nodular goiter in both cases.
• One patient had atypical Marine-Lenhart syndrome with bilateral PTC, while the other had toxic nodular goiter with PTC.
• These findings emphasize the importance of thorough evaluation for PTC in patients with hyperthyroidism and nodules.

Implications:

• Clinicians must consider the possibility of PTC even in the presence of hyperthyroidism and autonomously functioning thyroid nodules.
• Preoperative or intraoperative biopsy and consideration of total or near-total thyroidectomy are crucial for accurate diagnosis and to avoid reoperation for missed PTC.
• This approach ensures comprehensive management of complex thyroid conditions involving hyperthyroidism, nodules, and malignancy.