Hi @brighterdays, my oncologist ordered the test to specifically test the CYP2D6 enzyme to see if I was a good fit for Tamoxifen. It was either a blood or saliva test. Insurance covered it since I had breast cancer.

Later when my son turned 35 and needed to test because of my BRCA2 mutation, my breast surgeon recommended Color Genomics http://www.color.com for him so we used that. We ordered the extended package that included 30 cancer genes, some cardiac and other stuff, plus a whole list of enzymes needed to metabolize meds. I ordered a kit for myself too since it had the enzymes and many other cancer tests I didn't have before. The current price for the extended package is $249 for all that or $199 if a family member has a cancer mutation. Not covered by insurance at that time. Not sure about now. It also included discussing the results with a genetic counselor. We did it four years ago and at that time it required a doctor's order or a copy of the lab report showing a relative had a mutation (we submitted my lab report). I discovered another cancer mutation and that I was a poor metabolizer for lots of enzymes. I felt vindicated for all the times I told doctors so many meds did nothing for me (like pain meds) but had extreme side effects and they rolled their eyes.

10 years ago, my BRCA1/BRCA2 testing was only covered by insurance 10 years ago because I had an aunt and cousin with breast cancer. Things may have changed. Ask your breast cancer team to order whatever is covered.

Now when a doctor suggests a new med to me, the first thing I do is is google it by entering both the drug name followed by "metabolic pathway" in the search bar so I can see which enzymes are needed to metabolize that med. For example, try "tamoxifen metabolic pathway" and when you scroll down through the results you'll see "tamoxifen is metabolized via CYP2D6." Very helpful to me. Best of luck with any testing. 🙂