Posted Tuesday, November 16, 2004 by arjuna
TARA PARKER-POPE, The Wall Street Journal
Tuesday, November 16, 2004

(11-16) 08:00 PST (AP) --

Cancer risk can lurk in some surprising places in the family tree.

About 10 percent of common cancers are the result of heredity, but sometimes the risk isn't obvious. Many women, for instance, think they are at risk only if their mother's family had breast cancer and don't realize paternal risk plays just as much of a role. Similarly, if a man's family has a high incidence of breast cancer, it could increase his risk for prostate cancer. A family history of ovarian cancer may also increase a man's risk for melanoma, prostate or colon cancer.

Indeed, many seemingly unrelated cancers -- such as melanoma and pancreatic cancer or colon and endometrial cancer -- sometimes share a common genetic thread. But despite the revolution in genetics under way, hereditary risk for cancer often goes undetected. Fewer than one-third of patients have assessed their family health history, according to a report published last week by the Centers for Disease Control. In a bid to increase awareness of the link between family history, cancer and other diseases, the surgeon general has declared Thanksgiving Day "Family History" day, urging families to talk about their health in between helpings of turkey and pumpkin pie.

Even though most cancer isn't genetic, tracking down the people who do have genetic risks will go a long way toward catching and even preventing many cancers earlier, because people at known risk will be able to seek more aggressive screening and monitoring. Even a single case of cancer at an early age in the family, such as breast cancer before 45 or colon cancer before 50, should prompt a trip to a genetic counselor.

Genetic risk is so complex and confusing that even many doctors get it wrong. That was the case with 69-year-old Samuel Tauster, a Manalapan, N.J., chemist whose mother and cousins all died of breast cancer at an early age. After doctors told family members that breast-cancer risk could be passed only from mother to daughter, he didn't think his own children had to worry.

Later, he learned the doctor had been wrong. As a result, earlier this year, Mr. Tauster, his brother and sister were all tested for BRCA, a genetic mutation that triggers breast cancer in 50 percent to 85 percent of women who carry it. Mr. Tauster and his brother both tested positive for the mutation, and later so did his two daughters and his niece.

All three women opted for surgery to remove both breasts and ovaries as a preventive measure. "If I knew I was at high risk I would have been getting checked more often," says Mr. Tauster's 44-year-old daughter, who asked not to be named. "But nobody thought I was at risk because it was on my father's side."

BRCA mutations have been linked with melanoma, prostate, gall-bladder, colon, pancreatic and male breast cancers. Alison Estabrook, chief of breast surgery at St. Luke's Roosevelt Hospital in New York, says she recently saw a 36-year-old patient whose father and paternal grandfather both died of prostate cancer. The woman, as well as her two sisters, tested positive for BRCA. "If your father had colon or prostate cancer in his 40s, that might be a reason to be tested," says Dr. Estabrook. "But most people wouldn't link that with breast or ovarian cancer."

Researchers have identified several other hereditary links to cancer, although most are relatively rare. At least six genetic mutations are linked with hereditary risk for colon cancer, but families with the genes may also have higher rates of endometrial, ovarian, stomach, kidney, thyroid and childhood liver cancer. Rarely, pancreatic cancer may be linked to one of four genes that increase risk for melanoma. A family history of sarcoma can signal a genetic risk for melanoma, leukemia, breast, brain and adrenal cancers.

Figuring out whether there's a genetic link between cancers in your family is virtually impossible to do on your own. Seemingly obvious patterns, such as a high occurrence of melanoma in one family, may be misleading. While skin cancer appears to run in families, the reason often isn't genetic. The pattern instead may be due to the fact that the entire family regularly spent summers at the beach and everyone was exposed to the same harmful rays, says Peggy Cottrell, a New York genetic counselor who works with Dr. Estabrook.

To be sure that cancer isn't in your genes, the best bet is to talk with a genetic counselor. A risk assessment costs between $125 and $300 and likely will be covered by insurance with a doctor's referral. In addition to early-age cancer in the family, other reasons to discuss risk for carrying a gene include male breast cancer, ovarian and breast cancer in the same family, or any unusual cancers or clusters of a single type of cancer.

A genetic counselor will also want details about how the disease affected family members and where it occurred. Cancer found in both breasts or both kidneys, for instance, may be more significant than an occurrence on one side of the body. A melanoma lesion on the tip of the nose suggests the disease is due to sun exposure, while melanoma on the sole of the foot may signal a hereditary syndrome, triggering further testing.

Many people who seek genetic counseling are reassured that their risk is the same as everyone else's. But for those who go on to get tested for a cancer gene, insurance typically pays for the blood work, which can cost between $750 and $3,000, depending on the gene being studied. Even if a gene isn't identified, it's possible that a genetic risk still exists but the unique mutation wasn't found by the test. As a result, those who test negative for a cancer gene are often advised to undergo regular screening and monitoring, says Dawn C. Allain, ex-president of the National Society of Genetic Counselors and a genetic counselor at Waukesha Memorial Hospital in Waukesha, Wis.

As part of the surgeon general's initiative on family health history, the Department of Health and Human Services has launched a new Web tool at www.hhs.gov/familyhistory that allows you to track family health patterns that might signal higher risk for cancer or other diseases. The National Society of Genetic Counselors offers a database at www.nsgc.org/resourcelink.asp that helps you find a genetic counselor in your area.