The correct answer is A: RET
Comment: The cause of most medullary thyroid carcinoma cases is unknown. However, some are associated with multiple endocrine neoplasia (MEN). One of these diseases is Sipple syndrome (MEN-2B). It is an autosomal dominant inherited syndrome that includes bilateral C cell (medullary) carcinoma, pheochromocytoma, and hyperthyroidism. Both males and females carrying this gene usually become symptomatic in their thirties. The cancer cell of origin is the C cell which is the producer of calcitonin. Click here for the comparative pathology.
This Image IQ has been provided by the Center for Genomic Pathology
Zhou Z, Flesken-Nikitin A, Levine CG, et al. Suppression of melanotroph carcinogenesis leads to accelerated progression of pituitary anterior lobe tumors and medullary thyroid carcinomas in Rb+/- mice. Cancer Res. 2005 Feb 1;65(3):787-796. PubMed PMID: 15705875.
Matoso A, Zhou Z, Hayama R, et al. Cell lineage-specific interactions between Men1 and Rb in neuroendocrine neoplasia. Carcinogenesis. 2008 Mar;29(3):620-628. Epub 2007 Sep 24. PubMed PMID: 17893233.