Key Points
• Source: Journal of Thoracic Oncology
• Conclusion: “Patients with RET+ NSCLC have mainly thoracic and bone disease, and low TMB and PD-L1 expression. RETi significantly improve survival, while ICB may be active in selected patients.”
• In the current retrospective multi-center study, European researchers included patients with any-stage RET+ NSCLC from 31 cancer centers. Molecular profiling included DNA/RNA sequencing with or without FISH analyses. Other characteristics that were assessed included clinico-biological features and treatment outcomes with surgery, chemotherapy, immune-checkpoint blockers (ICB), chemotherapy-ICB, multi-tyrosine kinase inhibitors (MTKi), and RET inhibitors (RETi) .
• This RET-MAP study is the largest cohort to date (n=218) that analyzes the clinical and biological features, treatment outcomes, and natural history of those with RET+ lung cancer in a real-world setting.
• Limitations of the current study include no central information of the RET fusion and no data regarding heterogeneity in molecular testing, as well as the absence of uniform imaging workup.
• “Patients with RET+ NSCLC frequently had a smoking history and only in rare cases they exhibited other histology types than adenocarcinoma,” the authors concluded. “RET+ NSCLC displayed elements of cold tumors with generally low TMB and PD-L1 levels. However, selected patients did respond to ICB showing long benefit, and therefore patients with RET+ NSCLC should not be excluded from ICB treatment at some point during their disease evolution. Predictive biomarkers of response to therapy and the optimal therapeutic sequence between RETi and ICB with or without chemotherapy merits further investigation in this population.”