Tumor biomarker analysis or NGS analysis

[Ina3]

Hi everyone. Hope you are all healthy and safe during this time.

My dad who was doing very good , being on Keytruda for 18 months , last PET in January showed no brain mets, shrinking tumor in Lungs, but last week he did MRI and we were told that he has Leptomeningeal mets.

We were advised to do tumor biomarker analysis or NGS analysis of DNA for mutations that is done at Caris Life Sciences. At this point we have a tumor sample that was taken 2 years ago and we cannot get the new one. If tumors mutate, I was wondering how efficient it is to do these analysis on an older sample, especially some of the analysis was already done initially using the same sample , will we get any new information? Would doing it on Blood be a better option?

Caris Life Sciences only does this analysis and service on tumor samples only. Any other place that does the similar service for international patients using blood?

thanks

Ina

[Denzie Moderator Volunteer]

He needs to have a spinal tap to confirm leptomeningal disease. Did he ever have chemotherapy? If yes then there’s a strong possibility that the tumor has mutated around that. If his tumor has found a way to get around the Keytruda it has definitely mutated further but that only addresses the PDL1 levels not the genomic mutations.

In the meantime ask about pulsed tarceva. It gave Valerie Harper an additional 6 years.

[Ina3 in reply to Denzie]

Dear Denzie,

They suggested contrast MRI of the spine , is this same as Spinal tap?

He had Chemo initially, Pemetrexed, Zometa, Carbo but stopped around 6 months ago and continued only Keytruda.

So, checking genomic mutations on tumor sample still a good idea? Would Blood genomic test be preferable or not?

[Denzie Moderator Volunteer]

A spinal tap draws fluid from the meninges that’s surround the brain and spine. With any cancer you don’t know what you’re dealing with until you test the actual cancer. An MRI might confirm that it is suspicious for leptomeningal but without tumor cells you can’t be sure what you’re dealing with.

After having had carbo and pemetrexed he should have a new genomic testing. In the US it’s approved for Medicare because it saves giving some patients treatment that it is known to not respond to. A cancer grows because it has found a way around the chemotherapy it had.

You mention international patients. What country are you in? You might contact Foundation Medicine and see if they offer international testing. foundationmedicine.com

[Denzie Moderator Volunteer]

Further thought, the MRI may show a completely cloudy meninges but you need some of those cells to know what you’re dealing with.

[Ina3]

Denzie, thank you. Just called them and they will get back to me. My dad is in Georgia.

As for the spinal draw, if we do it and its not confirmed that its leptomeningal are there much options that WBRT? what I gathered, there are not many options when it comes to bran, especially the doctor said from MRI results that they way its ditsributed, it cannot be controlled by Megga knife.

Would Tarcive be still work if he doesn't have any EGFR?

Thank you so much for your responses and help and apologies for asking soo many questions but I am in a very desperate situation and don;t want to miss anything.

[Denzie Moderator Volunteer]

At this time there are few options. Whole brain radiation would be very important. There was a study that showed 10% of those who do not have EGFR redoing to Tarceva. My doctor said that’s only done in one study so I don’t know if the results are reproducible.

[txcowpatty]

If possible, a new biopsy would be better. My original results showed no PDL1 but a 2nd biopsy, after my lung cancer went to my kidney, showed a 5% PDL1. I'm not sure how accurate blood testing is. Worth a conversation with your oncologist.