Genetic testing

[SC19]

Hello all. My dad has just completed 10 x cabazitaxal and is stable but I am looking ahead at what to do next. We have not had genetic testing done yet so think this is the next plan. I wanted to know a bit more about it. I know that if BRCA 1/2 or ATM show up then he can have oliparib but I understand that this is the case in only approx 25% of patients? I wanted to know if there were other mutations they look for too, and if so can they be targeted with anything? Thanks in advance.

[dentaltwin]

I'm not sure specifically the answer to your question. Looking at the drug information it appears that the indication is mutation in BRCA gene--whether inherited (germline) or in the tumor itself (somatic).

There are a lot of other genes that can be tested for. On Tall_Allen's kind suggestion, I had genetic testing done a couple of months back, and they tested for many mutations that have been associated with an increased risk of prostate cancer. In my case I tested negative, despite the fact that my dad, me, and both of my brothers have had prostate cancer.

I should say that just because one has a mutation associated with prostate cancer, that does not mean there is a targeted therapy for that mutation (some of these mutations can be pretty specific--not only what gene is mutated but also HOW they are mutated). Also, most of the information I see about olaparib (Lynparza) is aimed at advanced ovarian cancer; the indications for prostate cancer may or may not be the same.

[cancervictim]

I find it interesting that this major study included men with mCRPC regardless of HRR status. They found that those with HRR had significant benefit but those without also benefitted. I wish they'd done a subgroup analysis on that cohort. For example, did men with a higher Gleason score or shorter doubling time benefit more than others? I understand that men with very aggressive cancer likely do have a genetic issue, it's just that it's more rare than those that have been identifed such as BRCA 1/2 , ATM etc.

evidence.nejm.org/doi/full/...

[Benkaymel]

Are you under the NHS? Did you have to self-pay for the genetic test or did the NHS provide it?

[SC19 in reply to Benkaymel]

Yes NHS and yes they provided it. I believe his blood test /liquid biopsy was sent off to the US to be tested and has now come back with a match to a trial.

[Benkaymel in reply to SC19]

Interesting. My MO has told me the NHS will not fund a genetic test for me. Which trust are you in? I'm in University Hospitals Sussex.

[SC19 in reply to Benkaymel]

He’s under The Christie in Manchester. It was offered after he finished cabazitaxal.