Category Archives: Medullary Thyroid Cancer

What is the RET proto-oncogene?

October 27, 2013Cancer, Medullary Thyroid Canceroncogene, proto-oncogene, retCalvin Lee, MD

RET Proto-Oncogene

Encodes a receptor tyrosine kinase
RET loss of function mutations are associated with Hirschsprung’s disease
RET gain of function associated with the development of various types of human cancers including medullary thyroid carcinoma, multiple endocrine neoplasias types 2A and 2B (MEN 2a and MEN 2b), pheochromocytoma and parathyroid hyperplasia

From an insurance standpoint on RET proto-oncogene testing for MTC – found on the internet:

Aetna considers diagnostic testing for germline point mutations in the RET gene medically necessary for members with apparently sporadic medullary thyroid carcinoma.

What is a proto-oncogene?

A proto-oncogene is a normal gene which can become an oncogene due to mutations or increased expression.

Ectopic ACTH production

October 14, 2013Cancer, Cushing's Syndrome, Ectopic ACTH, Lung, Medullary Thyroid Cancercushings disease, ectopic, lungCalvin Lee, MD

Ectopic ACTH Syndrome

Also known as EAS

Sources of Ectopic ACTH production.

Lung = most common cause.
Thymus
Thyroid – Medullary carcinoma
Ovary
Adrenal Gland – pheochromocytoma
Liver
Pancreas
Other neuroendocrine cancers

Difference between Cushings syndrome and Cushings disease

Cushings syndrome is cortisol excess from any cause.
Cushings disease is cortisol excess by pituitary ACTH over-secretion

Presentation found on the internet regarding Ectopic ACTH production:

http://www.med.unc.edu/medicine/web/ectopicacth.pdf