genetic testing, part 1

Last Friday Eric and I had the initial genetic-testing appointment at the oncologist’s practice. It was with their genetic-testing person, who is an oncologist rather than a trained certified genetic counselor. We found the appointment less than we had hoped: first we watched a very basic 30-minute video on genetic testing for breast cancer, then talked to Dr. G., who didn’t seem to have a lot of information she planned to impart to us. We asked a bunch of questions, which she answered…sort of. I guess you could describe it as: she didn’t answer in a teaching sort of way. She answered in a let’s-get-this-question-done-with sort of way. Not that she was impatient, but her answers didn’t really fill in the blanks for us. Nor did the video. However, she did loan Eric a big expensive textbook called THE GENETIC BASIS OF HUMAN CANCER, in which he plans to read the breast cancer chapter. Maybe that will answer some of our questions. Eric says she talked over my questions–I noticed, but didn’t really resent it, since I seem very thick-skinned in the conversational-style department. Eric resented it for me, though.

The upshot was that we went ahead and signed the consent form and I gave a bunch of blood samples for the testing, as I knew I probably would. There is only one company that does this BRCA gene testing. They will first look at three specific locations on the tumor-suppressing genes for the common Ashkenazi mutations (this is called multi-site testing). If there are none, then they’ll look at the whole gene for other mutations. Results of at least the first test will be available in about three weeks.

When we went to see Judy Garber at Dana-Farber (near Boston Harbor) she spread out the following odds for us:

Breast cancer–2-5% chance of having the BRCA1/BRCA2 mutations.
Breast cancer under 35 (which I was the first time)–10% chance.
Breast cancer under 35 with Ashkenazi background–30% chance.
Breast cancer twice under 40 with A. background–“almost 50/50 chance.”

This doctor, though not nearly so precise, said with my list of risk factors (including an aunt with ovarian cancer, which is related) she estimated the chance of me having the mutation at 70 or 80%. Whoah.

And as always, I figure if I don’t have a known mutation I probably just have one that no one is checking for yet. How else to explain this? Surely I don’t have that much need for growth of character.

Once we get the results, we may go back to Dana-Farber or to an actual counselor for discussion of the next steps, which may well include removing the (a.k.a. “my”) ovaries and a bilateral mastectomy, eventually. There is a 70% risk of ovarian cancer over one’s lifetime if one (okay, “I”) has the BRCA mutation(s). Neither Eric nor I feels confident that this doctor that we saw Friday is the person who can help us make those decisions!