The holidays are a great opportunity to ask family members about their health history.

Learning about your family’s health history can help you answer your doctor’s medical history questions. It can even help your doctor determine if you may be at risk for an inherited cancer like breast, colorectal, ovarian, prostate or endometrial cancer, which sometimes run in the family.

Keep in mind that just a small portion of cancers – about 5 to 10% – are actually inherited from a parent. More cancers – about one-third – are related to lifestyle choices like smoking, not exercising and making bad food choices.

Map out your family medical history

Here’s how to create your medical family tree.

1. Find out your ancestry. Include the country or countries where you ancestors came from originally. Some ancestries, like Jews of Ashkenazi (Eastern European) descent, have a higher risk for certain cancers.

2. List blood relatives. Include your first- (parents, siblings, children) and second- (nieces, nephews, aunts, uncles, grandparents) degree relatives. Add the current age of each or the age when they died.

3. Add cancer diagnoses, if any. Include the age when they were diagnosed with cancer, if you can find that out. List details, such as the part of the body where the cancer started and how the cancer was treated (chemotherapy, radiation therapy, surgery).

4. Include any birth defects or genetic disorders that you learn about.

Use the Surgeon General’s Office Family Health Portrait. This online tool helps track all family-related diseases, not just cancer.

Dig deeper for details

Hit a dead end while mapping out your tree? Try these tips to get more information:

• Speak with older relatives. They are usually good sources for information.
• Gather hospital records when there is some uncertainty.
  • Hospitals can release records directly to the patient.
  • Has a relative died? Hospitals can release records to the next of kin, the closest relative(s) entitled to the deceased individual’s property.

Watch out for “red flags”

After completing your family tree, review your findings and look for these “red flags.”

• Family member diagnosed with cancer before age 50.
• Family member who has had two or more different cancers.
• Two or more family members who have had the same type of cancer. Look specifically for breast, ovarian, colorectal, prostate or endometrial cancers.

If you find some of these “red flags,” speak with your doctor. He or she can help determine if you are at risk for hereditary cancer and may recommend that you speak with a genetic counselor.

A genetic counselor can help you decide if genetic testing is right for you. Genetic testing involves looking for abnormal genetic changes in a person’s blood sample.

Your doctor also can suggest changes you can make to prevent cancer and the screening exams you need to find the disease as early as possible.

Make your family medical tree a priority this holiday season. It may help ensure that you enjoy many more holidays with your loved ones.

Karen Lu is a professor in the Department of Gynecologic Oncology at The University of Texas MD Anderson Cancer Center in Houston, Texas.

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