• Origin: From parafollicular C cells; characterized by amyloid substance in the stroma.
  • Etiology: Sporadic or familial (MEN II) hyperparathyroidism, pheochromocytoma & medullary carcinoma.
  • Presentation: Secretion of calcitonin, prostaglandins, serotonin in the blood leading to diarrhea, flushing & bronchospasm.

Investigations

  • As before + for screening in familial type: calcitonin (if high in patient, used as a tumor marker).

Treatment

  • Thyroid: Total thyroidectomy & block dissection of lymph nodes.
  • Parathyroid: If sporadic, preserve all parathyroid glands; if familial, preserve only 1/2 parathyroid gland.