Photo by The Daily Courier.
Originally Published: October 9, 2016 10:13 a.m.
Tracing your family medical history makes sense when one or more members of a family face a cancer diagnosis of any kind. But it is particularly important when the diagnosis is made at a young age – before 50. One way to track the disease’s path is through a pedigree, or genealogy, chart.
In your genes
If you’ve had one first-degree female relative (sister, mother, daughter) diagnosed with breast cancer, your risk is doubled. If two first-degree relatives have been diagnosed, your risk is five times higher than average. (From Breastcancer.org)
Breast density can be inherited, so if your mother has dense breasts, it’s likely you will, too. Research has shown that dense breasts can be six times more likely to develop cancer. They also can make it harder for mammograms to detect breast cancer.
How to build a health history for your family
Find death certificates.
Search for obituaries.
Examine cemetery and funeral records.
Check mortality schedules.
Look for insurance records.
Find military service and pension records.
Research hospital and other medical records.
Learn about previous genetic testing in your family.
This record can be a useful tool in helping to identify whether you have higher risk for some health issues, including breast cancer, and will help your doctor recommend ways to reduce your risks. Heredity and genetics can play a role in early cancers (about 5 to 10 percent of breast cancers are thought to be hereditary, caused by abnormal genes passed from parent to child), while age and environmental factors such as smoking, diet, and dense breasts, can contribute to cancers in older family members.
The first step to charting disease is to collect as much medical information from family members as you can. Nancy Ledoyen, clinical navigator at the BreastCare Center at Yavapai Regional Medical Center East Campus, will help patients draw the family tree by hand. Sometimes she uses an online tool.
“I find it helpful to draw because people don’t remember some aspects,” she said, adding that seeing ancestors and disease diagramed on paper can trigger one’s memory about other family members and circumstances.
She asks: Who else has cancer in your family? Are they close relatives – first-degree relatives? Is cancer on the same side of the family?
If cancer appears in half the cases on the mother’s side and half on the father’s, more testing might be indicated, Ledoyen said. Also important is the age at which cancer is diagnosed.
“When cancer occurs at young ages where you wouldn’t expect, that’s always a red flag. We are looking for the patterns of cancers, what kinds of clusters, combination, age and who it is,” she said.
Cancer can be a disease that comes with aging, with multiple events happening, mutations that a person can’t overcome that could turn into cancer, Ledoyen explained. But a cancer diagnosis for someone in their twenties is a rare event. When it also has occurred in past generations, that’s when doctors may suggest further testing for an inherited gene.
Peeling back the layers is challenging, Ledoyen said. “We learn more and more about patterns and what we should be looking for. For instance, genes pass down equally; you have to look at both sides of the family.”
Even if an inherited gene mutation isn’t indicated, a higher than normal incidence of any kind of cancer could prove a good reason to be screened regularly, whether that means mammograms or colonoscopies, before something develops into cancer.