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What is All of the following are helpful for diagnosis of medullary Ca thyroid except - and explain in detail?
Important Diagnostic Features of Medullary carcinoma are :
Acellular amyloid deposition.
Calcitonin secretion by tumour cells.
Microscopically polygonal to spindle cell may form nests, trabeculae and even follicles.
Electron Microscopy showing variable no. of electron-dense granules (Membrane-bound) within the cytoplasm.