# RET fusion and RET mutation

Source: https://onco.cc/biomarkers/ret-fusion/  
OnCo record `ret-fusion` (Biomarker). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)"; commercial use needs a licence.

## TL;DR

RET fusions drive 1 to 2 percent of lung cancers and some thyroid cancers; RET point mutations drive medullary thyroid cancer. Selpercatinib is approved for RET fusions in any solid tumour and for RET-mutant medullary thyroid cancer; pralsetinib for RET fusion lung cancer.

## Summary

RET fusions (KIF5B::RET, CCDC6::RET, NCOA4::RET) are detected by RNA or DNA sequencing and FISH; RET point mutations (M918T, codon 634 and others, germline in MEN2) by sequencing. Selpercatinib (Retevmo) is labelled for RET fusion-positive NSCLC, RET fusion-positive thyroid cancer, RET-mutant medullary thyroid cancer and, since 2022, RET fusion-positive solid tumours after prior therapy, each as detected by an FDA-approved test; pralsetinib (Gavreto) for RET fusion-positive NSCLC. The Oncomine Dx Target Test, FoundationOne CDx and TruSight Oncology Comprehensive are the listed companion diagnostics.

## Fields

- Kind: Biomarker
- Last checked: 2026-09-23
- Also known as: RET fusion; RET rearrangement; RET fusion-positive; KIF5B-RET; KIF5B::RET; CCDC6-RET; RET mutation; RET M918T; RET-mutant medullary thyroid cancer; RET-altered
- Tags: biomarker; fusion

## Sources

- Retevmo prescribing information (DailyMed): https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=7fa848ba-a59c-4144-9f52-64d090f4d828
- Gavreto prescribing information (DailyMed): https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=16edd46e-28b8-f06d-e063-6394a90ae31b

## Connected records

- biomarkers: [ALK fusion (ALK-positive)](https://onco.cc/biomarkers/alk-fusion/), [NTRK1/2/3 gene fusion](https://onco.cc/biomarkers/ntrk-fusion/), [ROS1 fusion (ROS1-positive)](https://onco.cc/biomarkers/ros1-fusion/)
- cancers: [Medullary thyroid cancer](https://onco.cc/cancers/medullary-thyroid-cancer/), [Metastatic cancer (cancer that has spread)](https://onco.cc/cancers/metastatic-cancer/), [Non-small-cell lung cancer](https://onco.cc/cancers/nsclc/), [Papillary thyroid cancer](https://onco.cc/cancers/papillary-thyroid-cancer/), [Thyroid cancer](https://onco.cc/cancers/thyroid/)
- drugs: [FoundationOne CDx / Liquid CDx](https://onco.cc/drugs/foundationone-cdx/), [Oncomine Dx Target Test](https://onco.cc/drugs/oncomine-dx-target-test/), [Pralsetinib](https://onco.cc/drugs/pralsetinib/), [Selpercatinib](https://onco.cc/drugs/selpercatinib/), [TruSight Oncology Comprehensive](https://onco.cc/drugs/trusight-oncology-comprehensive/)
- terms: [Gene fusion](https://onco.cc/terms/gene-fusion/), [Tumour-agnostic (tissue-agnostic) approval](https://onco.cc/terms/tumour-agnostic/), [Tyrosine kinase inhibitor (TKI)](https://onco.cc/terms/tki-term/)
- targets: [RET](https://onco.cc/targets/ret/)

---
JSON: https://onco.cc/api/v1/entities/ret-fusion.json