A hereditary gene mutation increases a person’s risk of developing colorectal and other cancers, Veterans General Hospital colorectal surgeon Chang Shih-ching (張世慶) told a press conference yesterday.
“Through extensive investigation of a patient’s family medical history, it was found that a gene mutation in the family made them more susceptible to colorectal-related cancer,” Chang said.
Chang said a woman aged 31 who was diagnosed with colorectal cancer had recently undergone surgery to have the tumor removed. Because most colorectal cancer patients are in their 50s or older, the hospital looked for factors that may have contributed to the patient’s developing the cancer.
Chang looked into the woman’s family history and found that among 25 relatives, the patient’s grandmother and uncle were diagnosed with colorectal cancer at ages 75 and 42 respectively and her aunt with uterine cancer at age 50.
Chang said the discovery fit the profile of “Lynch syndrome,” in which more than three members of a family within two generations develop related cancers, with one of the patients developing cancer before the age of 50.
Through a DNA test, Chang found that members of the family had the “MLH1” gene mutation.
“When a cell is created in the body and there is something wrong with it, the MLH1 gene will automatically eliminate it — like an eraser. If this function fails, the person will be at a higher risk — at least 10 times higher — of getting cancer,” he said.
Chang said there were seven kinds of “erasers” in the body and the MLH1 gene was the toughest to deal with when it failed.
“I hope that my discovery will help establish a standard procedure so patients with Lynch syndrome and MLH1 problems will have something to go on.”
Chang said members of families with “Lynch syndrome” should visit a colorectal surgeons every two years after the age of 20.
For others, he recommended a colorectal exam once every three to five years after the age of 50, adding that the incidence of colorectal cancer was expected to increase because of diets with high oil intake.
RSS