A 41-year-old man presents with a 3-month history of chronic watery diarrhea and is found to have a thyroid nodule on examination. Vital signs show BP 148/92 mmHg, HR 102 bpm, RR 18, temperature 37°C, SpO2 98%. His sister underwent surgery for pheochromocytoma. Fine needle aspiration reveals a neuroendocrine tumor derived from parafollicular cells. Serum calcitonin is markedly elevated at 850 pg/mL. There is no palpable lymphadenopathy. Which substance is most likely elevated?
- A)Thyroglobulin
- B)TSH receptor antibodies
- C)Thyroid peroxidase antibodies
- D)Parathyroid hormone
- E)CalcitoninGABARITO
Explicação
Medullary thyroid carcinoma arises from parafollicular C cells and secretes calcitonin. It may occur in MEN 2 syndromes, which also include pheochromocytoma. Amyloid derived from calcitonin can be found in the tumor stroma, and diarrhea may result from hormone... Ver explicação completa e trilha adaptativa →