Colon Cancer in Your Family? It May Be an Inherited Syndrome

June 28, 2006 — -- Earlier this year, Gina Canada was stricken with a long bout of exhaustion and then vomiting. She thought it might be appendicitis but tests eventually revealed something far more pernicious -- colon cancer.

She was just 37 years old. To save her life, more than 40 percent of her colon had to be removed.

Soon after surgery, her physician, Dr. C. Richard Boland, approached her about her family's extensive experience with cancer -- her father, paternal aunts, brother and sister all have had cancer or died from it.

"Dr. Boland said because of the cancer in my family, it looked like it was a genetic problem," said Canada, who lives in Emory, Texas. "He tested me and confirmed ... that I have Lynch syndrome."

Normally, it can take a decade or longer for normal benign polyps to become cancerous, but for those with a genetic condition known as Lynch syndrome, the change can occur in as little as six months to two years.

Lynch syndrome is the leading hereditary cause of colon cancer, accounting for 4 to 5 percent of cases. It's estimated that every one to two people out 1,000 have the syndrome, and it affects all races equally.

Thankfully, new research from Scotland has provided an easier method for identifying patients at risk. The researchers studied the genes of 870 patients under age 55 who had colon cancer, looking carefully for specific mutations linked to Lynch syndrome. They published their findings in today's issue of the New England Journal of Medicine.

"The average age for an American to get colon cancer is 70, but for Lynch syndrome it's much younger, somewhere in the 40s," said Boland, chief of gastroenterology at Baylor University Medical Center in Dallas. He wrote an editorial on the findings.

The Scottish researchers created a Web site (http://www1.hgu.mrc.ac.uk/Softdata/MMRpredict.php) that allows doctors to determine patient risk for the mutations that cause Lynch syndrome. This tool can be used to decide whether to order a genetic screening or other medical interventions.

"And it's fairly easy," said Boland. "You don't need a lot of details."

Carrying the gene means the entire family is at risk, he said, and it is also important to know if a patient carries the gene when deciding on a treatment, since people with Lynch syndrome and colon cancer need a special operation on their colon.

Curable If Caught Early

Also, women with Lynch syndrome should be considered for uterine and ovarian removal surgery because they are also at very high risk to get cancer.

Since the polyps become cancerous more quickly for those with Lynch syndrome, patients need to be screened every two years instead of every 10 years, which is the recommendation for the rest of the population older than 50.

Canada will initially be screened with colonoscopies and CAT scans every six months. If her three children test positive for Lynch syndrome, they will also need more frequent colon cancer screenings.

"Colon cancer is so curable if caught early," Canada said. "And that's hopeful to me, for my children, my grandchildren down the line."

She is relieved to know about the syndrome.

"It was really hopeful to me," she said. "I was sick for several months and had no idea what it was. Now I know what I'm facing, I know what my children will be facing."