The Colon Club

Is anyone familiar with EXaCT1 testing or other Whole Exome Sequencing?

Did you have it done? What did it tell you that you already didn't know about your cancer? How did it help guide you through treatment options?

Here is what is on Weill-Cornell's website about it:

Whole Exome Sequencing by Next Generation Sequencing (NGS) has emerged as an efficient strategy to selectively sequence the coding regions of the genome as a more-cost effective alternative to whole genome sequencing. This new approach allows for the identification of numerous gene variations that may yield information about your cancer's development, prognosis and any potential targeted therapies that currently exist.

Unlike focused tests, typically called panel sequencing, the EXaCT-1 assay takes an unbiased, exploratory look at more than 20,000 genes in both healthy and malignant cells, allowing molecular pathologists to find alterations in the cancer-development process in unexpected regions of the exome. This type of test, known as whole exome sequencing, can be effective in advanced-stage patients for whom other treatments have failed because it uncovers mutations that the less comprehensive tests miss. In practice, this means, for example, that a patient with bladder cancer whom EXaCT-1 shows to share a mutation associated with breast cancer might benefit from a drug typically prescribed to fight the latter type of tumor.

I had Next Gen sequencing on the biopsied tissue of my tumor. The results provided the mutation profile of my tumor and the percentage of cells that had any specific mutation. The most significant find was the KRAS G12C mutation. This told the oncologist that certain EGFR targeting chemotherapy drugs would not work, and it was also necessary for applying for certain clinical trials that target specific mutations.

Hope this helps.

I looked it up as the name isn't necessarily descriptive.

It is genetic testing (not genomic testing on the tumor) and looks for genetic coding and variants or mutations that may be of use in treatment. I saw that there are research papers on this but I didn't read any of them. They would probably be a good place to look to determine how useful this testing is.

https://en.wikipedia.org/wiki/Exome_sequencing

I like how Whole Exome Sequencing finds mutations that less comprehensive tests miss. If, for example, EXaCT-1 shows my husband's liver met (I assume Weill-Cornell is testing the met to the liver because I made the slide request to MSK) shares a mutation associated with breast cancer, he might benefit from a drug typically prescribed to fight the latter type of tumor. Because of this, I can see why the description says that the test "can be effective in advanced-stage patients for whom other treatments have failed." My husband is nowhere near treatment failure as so far, none of his treatments can be said to have failed, but I am glad that we will have as much information as technologically possible.