Medical policy medical policy a-z chapters new policies search    genetic testing for medullary carcinoma of the thyroid (ret proto-oncogene) â  chapter: genetic testing â© blue cross and blue shield of montana â  current effective date: 09/01/2007 original effective date: 09/01/2007 description medullary carcinoma of the thyroid is an uncommon type of thyroid cancer. cheap viagra Three distinct but related familial cancer syndromes together are responsible for approximately one-fourth of the incidence of medullary carcinoma of the thyroid; the remaining three-fourths are sporadic. The 3 inherited syndromes include multiple endocrine neoplasia (men) types 2a and 2b and familial medullary thyroid cancer (fmtc). Men 2a, men 2b, and fmtc are all dominantly inherited. buy viagra online boots Point mutations of the germline ret gene, located on chromosome 10, are associated with inheritance of men 2a, men 2b, or fmtc. Medullary thyroid cancer is curable surgically if detected before it has spread to regional lymph nodes. However, if a thyroid nodule is the first sign of disease, lymph node involvement at diagnosis may be found in up to 75% of patients. buy viagra online Surveillance by annual biochemical monitoring for c-cell hyperplasia has been used to identify those with the inherited disease before it progresses beyond the earliest stages. cheap viagra online Recently, genetic assays for ret mutations have been used as an alternative to annual biochemical testing, in patients with a known family history of men 2a, 2b, or fmtc. Annual biochemical screening can be stopped in those patients who test negative for mutations. generic viagra Patients who test positive may undergo immediate thyroidectomy or postpone thyroidectomy until biochemical tests suggest evolving medullary cancer. Genetic assays have also been used to determine if new cases of medullary thyroid cancer without a family history are truly sporadic in origin. A positive test in this setting should initiate evaluation of family members. viagra triangle chicago hotels In addition, a positive test may prompt screening for pheochromocytoma , a component of men 2a and 2b, in the affected patient. generic viagra safe yahoo Policy prior authorization for genetic testing of medullary carcinoma of the thyroid is recommended. generic viagra safe yahoo To authorize, call blue cross and blue shield of montana (b. viagra pills canada viagra without a dosctor prescription