breast cancer and further risks from radiation

[katarina777]

Dr. Paul, you just responded to a woman on this topic. When you have been diagnosed with bc, and have had chemo and radiation, how great is the risk of the therapy itself leading to another cancer, and what kinds? Also, my 18 year old son has had many x-rays because he often injures himself. His father died of colon cancer, and I had it, even if we were the first in our families. how great is my son's risk?

[katarina777]

Thank you so much for your comprehensive answer.
I hope you know just how much you are appreciated here. kat

[PaulMD]

Chemotherapy and radiation therapy for breast cancer may indeed increase the risk of developing a second malignancy, mostly hematologic ones (like leukemia).  However, the risk of developing these is significantly lesser than the risk of the breast cancer returning or spreading if the patient opts not to receive chemo and radiation.  From the treatment, it is expected that the risk of second malignancy is less than 2 or 3% in the next 10 to 15 years, which is markedly lower than the 40-50% breast cancer recurrence rate in 10 years if chemotherapy and radiation is not given.

It is very hard to give a numerical value to your son's risk of developing cancer, and even the many x-rays that he had may not increase his risk.  The family history of cancer is more significant and he may benefit from early surveillance work-ups such as colonoscopy, fecal occult blood, or sigmoidoscopy.  these can be done 10 years ahead of the earliest documented colon cancer in the family (like if his dad was diagnosed with colon cancer at 40 years, he should undergo surveillance at 30 years), or at age 40, whichever is earlier.

Regards.