Papillary thyroid carcinoma in a 5-year old child, mimicking lymphoma in presentation

Thyroid cancer is very rare in children and papillary thyroid carcinoma (PTC) represents the most common type. Patients are frequently in the second decade of life and complain of painless enlargement of the gland. Pediatric PTC has unique clinicopathologic characteristics that make it different from the adult counterpart. The biologic behavior tends to be aggressive and patients frequently present with advanced disease. Herein, we report a case with an unusual presentation. A 5-year-old child manifested with fever, night sweats, cervical lymphadenopathy, and weight loss for 2 months. He also complained of mild cough and shortness of breath. Clinical suspicion of tuberculosis or lymphoma was raised, but laboratory workup was unremarkable. Cervical lymph node excision was done, and the histopathologic examination showed metastatic PTC. The patient underwent surgical and radioactive therapy and remained in complete remission for 5 years. Unfortunately, the disease ultimately relapsed with disseminated metastasis and the patient passed away.