Thyroid Gland
Medullary carcinoma of thyroid gland: Microscopic medium power of the tumor cells and large amounts of amoprhous homogeneous hyaline substance (amyloid substances).

This case from a 36-year-old thai male presented with neck mass for 3 to 4 years duration. He had not had hoarseness of voice or hard breathing. Respite of taking antithyroid drugs for a period of time, the neck mass did not responded well. The 4-cm-in-diameter mass was surgically removed.