The short answer is probably not. Most colorectal cancer develops as we age without any notable family history.

But about one in five people with colorectal cancer will have a close family link.

Getting to know that risk is important.

It may mean earlier or more frequent screening. It definitely means talking to your family, learning about Aunt Mary’s uterine cancer, Dad’s polyps, or Grandmother’s stomach problems when she was 35. It means telling them about your own cancer or polyps.

The National Colorectal Cancer Roundtable has a new website to help you search and share your family history with Family PLZ.

Family PLZ shows you how to put a family health history together and what to do with the information.

Some resources for compiling your family health history gathered by Family PLZ

• The Surgeon’s General’s My Family Health Portrait is an ideal tool to use at family gatherings to build a family health history.
• Genetic Alliance can help you assemble and print a personalized booklet Does It Run In the Family that you can share with your family and doctor.
• Mayo Clinic has tips for getting reluctant family members to share medical history, as well as what information to collect.
• Fight Colorectal Cancer has a list of questions to ask yourself to determine your risk for colorectal cancer.

What Does Your Risk Mean?

• Average risk people have about a 6 percent lifetime risk of getting colorectal cancer. That risk can double or go up as much as four times depending on how many relatives you have colorectal cancer, how close those relatives are to you, and their age when they were diagnosed according to a chart from the American Cancer Society.
• Everyone should be screened beginning at age 50, but family history may mean earlier or more frequent colonoscopy screening. The Colon Cancer Prevention Project has a detailed screening tip sheet that helps make screening plans, intended for doctors, but helpful for patients as well.
• For more information about inherited colorectal cancer which can significantly increase your risk watch Inherited Colorectal Cancer: Does It Run in Your Family, a Fight Colorectal Cancer webinar with Dr. Henry Lynch.

Colon cancer patients with a first-degree relative who also had colon cancer have a significantly better prognosis.

In a recent study, even after all risk factors were taken into consideration, they had less chance of cancer recurring and less chance of dying than people without a close family history.

However, the same thing was not true for rectal cancer.

Researchers in Sweden questioned 318 consecutive colorectal cancer patients about their family cancer history.  They found 31 (10 percent) had at least one first-degree relative who also had colorectal cancer — a parent, sister or brother, or child.  They then followed all of the patients for the next six years, watching for recurrences and deaths.

Two patients met the criteria for Lynch syndrome and were not included in the study.

They found a 63 percent reduction in risk  for recurrence among patients who also had a family member with colorectal cancer and a 75 percent reduction in the risk of dying.  This reduced risk could not be explained by other factors including the patient’s age or sex, the cancer stage, tumor differentiation or invasion of nearby blood vessels.

Helgi Birgisson and her team at Uppsala University in Sweden concluded,

Family history for colorectal cancer in a first-degree relative is an individual prognostic factor in patients with colon cancer and could not be explained by known clinico-pathological factors. The value of family history taking in patients with colon cancer is therefore not only to identify families with hereditary colorectal cancer, but also to add information to the prognosis of the patients.

Another study, published in 2008 in the Journal of the American Medical Association, found a smaller but similar association between family history and stage III colon cancer recovery.  In that review of 1,087 patients with stage III colon cancer, 195 (17.9 percent) had a first-degree relative with colorectal cancer.  Following them for a median of five and a half years, researchers found that disease-free survival, recurrence-free survival, and overall survival were significantly better for patients who had a close family member with colorectal cancer.

Other than the fact that patients with a family history were less likely to have had a bowel obstruction when they were first diagnosed, there were no significant differences between people with close family histories of colorectal cancer and those without them.  Sex, race, age, tumor characteristics, smoking history, diet, and exercise were all similar.  Microsatellite instability or DNA mismatch repair status didn’t appear  to affect the lowered risk.

Overall, patients with a first-degree relative with colorectal cancer had a 28 percent reduced risk of having cancer return or dying of the disease.  This improved outcome was even stronger when there was more than one close relative.  Among these stage III colon cancer patients, all of whom received chemotherapy, 29 percent experienced recurrence or death compared to 38 percent of those who had no family history.

Jennifer Chan, MD, MPH, and her colleagues analyzing the CALGB 89803 clinical trial concluded,

Among patients with stage III colon cancer receiving adjuvant chemotherapy, a family history of colorectal cancer is associated with a significant reduction in cancer recurrence and death.

SOURCES: Birgisson et al., Familial Cancer,Volume 8, Number 4, December, 2009.

Chan et al, Journal of the American Medical Association, Volume  299, Number 21, June 4, 2008.

Keeping Track of Family Health History

Today while you’re digesting turkey or washing the Thanksgiving dinner dishes, take time to talk about your family’s health history.  Steven K. Galson, M.D., M.P.H., the acting Surgeon General, has declared Thanksgiving 2008 the fifth annual National Family History Day.

Families are encouraged to share health information to identify diseases that might be inherited or lifestyles that may contribute to medical problems.  Family histories can lead to a discussion with your doctor about tests you may need or changes you should make to prevent cancer and other diseases.

My Family Health History, a tool developed by the Surgeon General, can help you make a drawing of your family tree and a chart of your family’s health history.  They both can be printed out and shared with others in your family and with your doctor.

Dr. Galston points out,

Talking about and sharing your own family health history is something you can do right now in order to gain an understanding of your health and the health of family members. It’s a starting point for taking fuller charge of your own health future. Tracing the illnesses your grandparents, parents, and additional blood relatives have suffered from can help your health care provider predict diseases and disorders from which you could be at risk.

About 20 percent of colorectal cancer has a family connection. Knowing if there is a history of colorectal polyps or cancer in a close relative, in more than one relative, or in two or more generations is important to decide on a personal prevention strategy.  People who were diagnosed under the age of 60 are especially important to note.

People with a family history of colon or rectal cancer may have a smaller risk of having the cancer return or of dying from the disease according to a new study published this week in the Journal of the American Medical Association.

Researchers followed nearly 1,100 patients with stage III colon cancer who were being treated with chemotherapy, 195 of whom had at least one close family member who also had been diagnosed with colorectal cancer.  Fifty-seven of them had a cancer recurrence or died (29 percent).  Among the 892 patients with no family history, 343 died or had cancer return (38 percent.)

Patients with one family member with colorectal cancer had about a 25 percent reduced risk of recurrence or death than those with no family history.  When there were two or more affected close relatives, risk of dying or having cancer return was cut in half.

The scientists tested tumors for microsatellite instability (MSI) and for proteins associated with mismatch repair genes, two molecular factors that are associated with better survival.  However, family history was independent of MSI and mismatch repair.

Close family members were first-degree relatives — parents, siblings, or children.

Jennifer A. Chan, MD, MPH and her colleagues wrote,

Among patients with stage III colon cancer receiving adjuvant chemotherapy, a family history of colorectal cancer is associated with a significant reduction in cancer recurrence and death

Watch a video report about the research.

SOURCE: Chan et al,, Journal of the American Medical Association, Volume 299, Number 21, June 4, 2008.