RET Codon 918 Mutation Analysis
Indication
Germline RET codon 918 mutation substituting methionine for threonine (p.M918T) is an activating point mutation found in approximately 95% cases of multiple endocrine neoplasia Type 2B (MEN2B), a group of familial cancer syndromes characterized by medullary thyroid carcinoma, pheochromocytoma, parathyroid hyperplasia and ganglioneuromatosis of the gastroenteric mucosa.
Additionally, somatic mutations of RET are reported in 20-80% of sporadic medullary thyroid carcinomas and rare cases of apparently isolated intensional ganglioneuromatosis, with vast majority affecting codon 918. The tumors with p.M918T mutation are reported to display a more aggressive phenotype. The assay offered by our laboratory detects activating mutations in codon 918 in exon 16 of RET and aids in the assessment of patients in appropriate clinicopathologic settings.
Methodology
PCR-based DNA Pyrosequencing. The assay is also available on a next generation sequencing platform for solid tumors.
Test Parameters
This assay will detect mutations in codon 918 in exon 16 of the RET gene. The sensitivity of detection is approximately one mutated cell per ten total cells in the sample (10%).
Turnaround Time
10 days
Sample Requirements
Formalin-fixed, paraffin embedded tissue blocks or 10 unstained slides containing adequate amounts of tumor to be analyzed (see above sensitivity), with areas to be tested clearly indicated on the slides/block. Comparison of normal and tumor, or several different areas of tumor can be done, for additional charge.
Please provide a copy of the corresponding pathology report.
CPT Codes
81404
Additional charges may apply for tissue extraction.
The CPT codes provided are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payer being billed.

