February 5, 2014
News Review From Harvard Medical School -- Cancer Doctors to Seek Shorter Family History
Cancer doctors should ask about patients' family medical history. But two generations are enough, new guidelines say. The American Society of Clinical Oncology released the guidelines. They say that doctors should ask about cancer among patients' first- and second-degree relatives. But going back three generations -- the old advice --- is not necessary. A panel of experts based the changes on a review of evidence. They decided that information about more distant relatives is less likely to be correct. First-degree relatives include parents, children, brothers and sisters. Second-degree relatives include grandparents, aunts and uncles. Nieces, nephews, grandchildren and half-siblings also are considered second-degree. Doctors should ask the relative's type of cancer, age when diagnosed and race or ethnic group, the guidelines say. They also should note whether each person is on the mother's or father's side. And they should ask about relatives' cancer-related genetic testing. Knowing family history can help provide more personalized treatment, the guidelines say. The Journal of Clinical Oncology published the guidelines. HealthDay News wrote about them February 4.
By Howard LeWine, M.D.
Harvard Medical School
What Is the Doctor's Reaction?
Doctors differ on how much detail they ask about family medical history. It can be very time consuming, and often doesn't change advice to the patient or relatives.
But for certain cancers, family history is very important. It helps determine how likely it is that you and other family members have a genetic change that increases cancer risk. This is especially true for breast and colorectal cancers.
This article provides guidance for doctors on how much information to collect about personal and family risks of these two cancers. Based on their research, the authors suggest limiting family history to first- and second-degree relatives.
- First-degree relatives are parents, full siblings and children.
- Second-degree relatives are grandparents, grandchildren, aunts, uncles, nephews, nieces and half-siblings.
Asking about third-degree relatives does not provide added value. These relatives include first cousins, great-grandparents and great-grandchildren.
If a family member has been diagnosed with cancer, doctors ideally need to know:
- The exact type of cancer
- The age at diagnosis, or the date of diagnosis and the person’s current age (or the age at which he or she died)
- The relationship to the patient, noting if the family member is on the mother's or father's side
- Results of any genetic testing done on family members
Regarding breast cancer risk, your doctor will especially want to know if:
- Any male blood relative has had breast cancer
- Any blood relative was diagnosed with breast cancer at age 50 or younger
- Any blood relative has had tests done to look for genes related to a higher risk of breast cancer (if so, the doctor will want to know the test results)
- Two or more blood relatives on the same side of the family have been diagnosed with breast or ovarian cancer
Regarding colorectal cancer risk, your doctor will especially want to know if:
- A first-degree blood relative has had colorectal, ovarian or endometrial cancer diagnosed at age 50 or younger
- Two or more blood relatives on the same side of the family have had colorectal, ovarian or endometrial cancer at any age
These details help guide who should pursue genetic counseling.
What Changes Can I Make Now?
Don't wait for your doctor to ask about family medical history. You should gather details for other diagnoses, too, such as heart disease and type 2 diabetes. Creating a family health tree also helps to determine your risk for these diseases, which are even more common than cancer.
Medical information about first-degree relatives is most important. Try to get as much details as you can about second-degree relatives also.
- Find out what diseases each family member was diagnosed with and at what age. In general, an early age at diagnosis is more likely to be significant for your health than a condition diagnosed at an older age.
- Try to determine the accuracy of the information. Talk with multiple relatives. If you can, get medical records and death certificates.
- Record the health habits and lifestyle factors of family members along with medical diagnoses. For example, if your father is a smoker, it might be the more important reason for an early heart attack. But if your father was a slim, non-smoking, physically active guy, his heart attack might have a genetic basis that you could inherit.
Everyone in your family stands to benefit from a complete and accurate family medical history. So seek the help of your relatives to fill in the details.
You can create your family medical tree online. The website is called My Family Health Portrait. Consider sharing it with the rest of your family.
What Can I Expect Looking to the Future?
A few years ago, there was a big push to have everyone record a family medical history. Not so much recently. But its importance has never diminished.