When Cancer Strikes Close to Home

I saw a very concerned patient last week. Her 59 year old sister had recently been diagnosed with early stage breast cancer on a routine mammogram. All of my patient’s friends were telling her she had better see her doctor right away and get additional testing because she was now at increased risk.

My patient, who is 50 years old, had a normal breast exam and a recent negative mammogram. Her sister had had a negative BRCA test. There was no other family history of breast or ovarian cancer, or any other cancers identified with known gene mutations.

My patient was shocked when I told her that her sister’s breast cancer did not increase her risk of breast cancer high enough to warrant anything other than routine screening. Her sister’s breast cancer, being post-menopausal, the only one in the family and occuring in the absence of a BRCA mutation, was almost certainly a sporadic cancer. I explained that only 10% of breast cancers are genetically-linked.

We went through my patient’s Gail Model predictions together, and I showed her that her sister’s cancer raised her 5 year breast cancer risk infinitesimally, and her lifetime risk from 9 to 15%. But the Gail and other risk assessment models do not take BRCA results into account, and her sister’s negative BRCA result pretty much nullified that increased risk based on family history. Of course there is always a tiny chance that the test was a false negative, but in the absence of any other family history and her sister’s age at diagnosis, I felt that these odds were low. Finally, even if she did have a 15% risk, that risk is not high enough to warrant routine breast MRI at this time.

We looked at her last mammogram report. I explained that I usually order routine sonograms when the radiologist reports that the breasts are of increased density that limits the sensitivity of the mammogram. But my patient’s breasts were described in the report as being “heterogeneously dense”, a very common descriptor in routine mammograms in her age group. I did not see an indication to order routine sonogram.

I gave her my mantra – Everyone who gets a cancer is part of a family, but not all cancers are familial.

She understood but remained worried. Couldn’t we do something?

So we agreed that we would add a sonogram for now. I explained that because it was not clearly indicated, her insurance would most likely decline to pay for it and she was comfortable with that. My plan was definitely not evidence-based and unquestionably a medico-legal punt, but my patient left feeling her fears had been addressed.

I made her repeat the mantra back to me. “Everyone who gets cancer is part of a family, but not every cancer is familial.” I hoped if she repeated it enough it would sink in.

But when cancer strikes so close to home, it’s hard not to worry that your home is the one with a bull’s eye on its roof.