Do I need genetic testing before starting targeted therapy for breast cancer?
Community Member
10 days agoHi all I just wanted to know before you started targeted therapy did they do a genetic test for all in this group. I had a genetic test done in 2023 before I started chemo and Immunotherapy but when i was in remission until October of 2025 and I was told I had HERS positive cancer this time not triple negative as previous but They didn't mention anything about having another Genetic test before starting Targerted Therapy infusion just found out from someone else who said her oncologist said they definitely should do genetic testing before starting targeted therapy for Breast cancer she lives in another state and when she told me this i was like I have genetics test in 2023 but they didn't mention I should redo it again because my Cancer is different and already had surgery when my surgeon find it in october while it 1.4 cm and in stage 1 all margins clear and surrounding tissue was benign but i did four weeks of radiation and now am on Targerted therapy and they did the nuclear stress test for heart before i started as.this medication can cause heart and lung problem Will be getting heart test every 3 months and I do this therapy once every three week will have my third infusion on April 2 and have the nuclear stress test on April 8. The first test was good so i could start the targeted therapy. I am on Trastumzumab.
Community Member
10 days agoGenetic testing practices can vary between oncologists and treatment centers, so it's completely understandable to have questions about whether additional testing might be needed when cancer characteristics change. Since your cancer has changed from triple negative to HER2 positive, this is definitely worth discussing with your oncology team. They can explain their specific approach to genetic testing and whether your 2023 results provide all the information needed for your current treatment plan. It sounds like you're being well-monitored with regular heart function tests, which is important for HER2-targeted therapies. Many others in this community have navigated similar questions about testing protocols, so hopefully others will share their experiences too.
Community Member
6 days agoYes I had my genetic testing done before chemo started. And mine was negative!
Community Member
6 days agoI had mine done before chemo also in 2023 and mine was negative but just wondering if you have a different type of cancer HERS Positive this time that requires targeted therapy Herceptin taking generic brand every three weeks.I was questioning if they had to do different genetic testing I will be asking my oncologist because a friend told me her oncologist said there is a special test before you can started Targeted therapy I know you have to have a heart test to make sure your projectile rate is ok enough to start and have test every three months.Thanks for the response and God bless and walk with each of my pink sisters .
Community Member
5 days agoI had genetic testing. I am BRCA 1 positive.
Community Member
5 days agoYes I had BRCA 1 and 2nd Genetic test in 2023 I was negative and after reading some more on Internet about this I know what type of test her oncologist was talking about I should definitely have it was the Fish and IHC test Done by Pathology Doctor after my surgeon removed the tumor and surrounding tissue in 2025 to Check if i had HERS positive because with first test it was equivocal so he had to do FISH test to confirm I actually had HERS positive Because targerted therapy treatment is for this type of Breast Cancer. May we all have better days ahead and blessings to all.
Community Member
2 days agoMy genetic test was completed after the 1st pathology report. That report initially said that I was hers - 2nd opinion came back positive.
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