What is the RET gene mutation in stage 4 NSCLC at 65?

Question

Hello doctor,

My mother is 65 years old and was recently diagnosed with stage 4 non-small cell lung cancer, and after the comprehensive genomic profiling, her report came back showing a RET gene fusion mutation. We had never heard of this before, and the oncologist mentioned something about Selpercatinib, but spoke very fast, and we could not understand much. Her CEA levels are at 8.7 ng/mL, and she already has small metastases in her liver and adrenal gland. She is a non-smoker, and otherwise her heart and kidney function are fine.

She is on blood pressure medication, Amlodipine 5 mg daily, and we are worried about drug interactions. The report also mentions a PD-L1 expression of 15 %, and we do not understand if that means immunotherapy like Pembrolizumab would also work, or if the RET mutation treatment is separate.

What exactly does the RET gene mutation mean in stage 4 non-small cell lung cancer, and does having this mutation at her age change the prognosis significantly?
Is targeted therapy safer than chemotherapy for her?

Please help.

Thank you.

Answer 1

Hello,

Welcome to icliniq.com.

I understand your concern.

RET (rearranged during transfection) gene fusion means there is a change in the cancer cell’s DNA (deoxyribonucleic acid), which makes the cells grow continuously. This type of mutation is important because it can be specifically targeted with special medicines. In stage 4 lung cancer, the disease has spread to other organs like the liver and adrenal gland. But the presence of a RET mutation is a positive point because it gives an effective treatment option.

Selpercatinib is a targeted therapy that blocks this abnormal RET signal. It is taken as a tablet and usually works better than chemotherapy in such cases. This medicine is generally safer than chemotherapy. Side effects are usually mild, like increased blood pressure, tiredness, or liver test changes, and are manageable. Amlodipine can be continued, but blood pressure (BP) should be monitored regularly because Selpercatinib can increase BP.

A PD-L1 level of 15 % means immunotherapy is possible, but in RET mutation cases, targeted therapy is preferred first. Immunotherapy is usually used later if needed. The CEA (carcinoembryonic antigen) level is just a marker to monitor the disease. High value shows disease activity but does not change treatment directly. At age 65, if overall health is good, treatment response can still be good. Age alone does not worsen prognosis significantly.

Overall, targeted therapy like Selpercatinib offers better control of the disease with fewer side effects and improved quality of life.

I hope this information helps you.

Revert in case of queries.

Regards.