Laboratory Test Information Guide

Details for Familial Medullary Thyroid Carcinoma

Test Name: Familial Medullary Thyroid Carcinoma
Alternate Name(s): FMTC
Laboratory: Molecular Diagnostics
Specimen Type: Whole blood-3 x 4 mL Lavender EDTA top Vacutainer tube
Collection Information: Blood samples must be maintained at room temperature.
Requisition: MOLECULAR DIAGNOSTIC REQUISITION
Test Schedule: As Required
Monday - Friday
0800 - 1600 h
Turnaround time from when specimen
is received in testing laboratory:
 
Routine
3 months
Stat
 
 
Reference Range: See report
Effective Date:  
Revised Date: 2016-03-21
Critical Value: N/A
Interpretive Comments: Multiple endocrine neoplasia type 2 (MEN2) is an autosomal dominant form of inheritable cancer affecting tissues derived from the neural ectoderm. It is characterised by medullary thyroid carcinoma and phaeochromocytoma. Co-inheritance of activating mis-sense mutations in the RET oncogene with FMTC, MEN 2A and MEN 2B has been demonstrated 1,2,3,4. It has been reported5 that specific RET mutations can predict both phenotypic expression and tumour grade in patients with MEN 2. The lowest risk for MTC has been reported5 to be associated with mutations affecting RET codons 609, 768, 790, 791, 804, and 891, an intermediate level of risk for mutations affecting RET codons 611, 618, 620, and 634, and the highest level of risk for individuals with mutations affecting RET codons 883 and 918. As well we look for the sequence variant (2712C>G:Ser904Ser). The significance of this variant is unknown at this time, though it is noted that it has been reported as a possible genetic modifier of MEN 2A6. If further analysis is indicated, please contact our laboratory.

References

*Sequence according to GenBank RET cDNA seq. Accession #NM_020630. Nucleotide seq. numbered from the initial ATG of the cDNA coding sequence according to the protocol from Dunnen and Antonarakis, Hum Genet, (2001) 109:121-124.


1. Mulligan, L. et al. (1993) Nature 363: 458-460
2. Asai N. et al (1995) Mol Cell Biol 15:1613-1619
3. Santoro M et al (1995) Science 267:381-383
4. Xing S. et al ((1996) Endocrinology 137:1512-1519
5. Yip et al. (2003) Arch Surg.138(4):409-16
6. Robledo et al (2003) Cancer Research 63:1814-1817

Special Processing:  
Comments: For more information click on:

Molecular Diagnostic Laboratory
Method of Analysis: DNA Sequence Analysis
Critical Information Required: Please note that these samples will be subjected to direct mutational analysis. As this is an inheritable disorder, a family pedigree will be required.
Storage & Shipment: Must be received within 5 days of collection, shipped at room temperature by courier/overnight delivery.
System Codes: 
Cerner
 
 
Referred To:  

Questions? Comments? Contact Laura Gopaul