Among the many risk factors of cancer, “family history” and “heredity” have great influence, and even are the main causes of some cancers. So, when we know that there are cancer patients in our families and relatives, what is the risk of our own disease? How to discover and avoid it in advance?
Zhang Kai, deputy director of the cancer prevention physical examination center of the Cancer Hospital of the Chinese Academy of Medical Sciences, told reporters that the first thing to be explained is that among all cancer patients, “familial genetic tumor” only accounts for 5%, about 20% of the tumor incidence is related to genetic mutation, while about 80% of the cases are caused by non genetic factors. Therefore, having relatives suffering from cancer does not mean that the whole family is a high-risk group.
However, Zhang Kai stressed that some people with family history of cancer should have the awareness of screening earlier than the general population. Colorectal cancer, breast cancer, ovarian cancer, endometrial cancer, gastric cancer and other family genetic cancer are ranked in the top few. People with these family history can refer to the following screening and precautions:
colorectal cancer. The risk of colorectal cancer increased from 1.8% to 3.4% for those over 50 years old with more than one first-degree relative, and to 6.9% if more than two first-degree relatives had colorectal cancer.
for people with family history of colorectal cancer, it is recommended to start preventive screening from the age of 40 or even earlier. The recommended method is colonoscopy or fecal occult blood test, which should be done 1-2 times a year; at the same time, more attention should be paid to diet health than ordinary people, and less high salt and greasy food should be eaten.
breast tumor. Family history of breast cancer, especially the mother and sister are breast cancer patients, the risk of cancer increased by 1.5-3 times, if two close relatives of breast cancer, the prevalence rate increased 7 times. It is suggested that BRCA gene test should be carried out as soon as possible. If BRCA1 / 2 gene mutation is found, the lifetime risk of yellow race people will be as high as 56%. Doctors can be consulted to take measures to reduce the risk. For high-risk population with negative BRCA gene test, screening should be conducted before the age of 40. Ultrasound is the main method before menopause, and ultrasound plus molybdenum target is mainly used in postmenopausal women. The interval of screening is 0.5-1 year.
people with family history of breast cancer should try to reduce the intake of estrogen and various kinds of food containing estrogen to avoid surgical trauma. BRCA mutation carriers also suggest early consideration of marriage and childbearing, because fertility plays a protective role in breast cancer. In addition, drug and even surgical prevention can be considered as soon as possible after birth.
ovarian cancer. The risk of ovarian cancer is about 1% in average women, while the risk of BRCA1 / 2 mutation carriers is 23% – 54%. It is difficult to detect ovarian cancer early. It is suggested that women with family history of ovarian cancer should consider BRCA gene detection. For BRCA mutation carriers, it is recommended that they should take pelvic examination, blood CA125 and transvaginal ultrasound screening from the age of 30 to 35 before they have completed their childbirth.
endometrial carcinoma. Most of endometrial cancer is sporadic, but about 5% – 10% of them are hereditary endometrial carcinoma. The age of onset of the latter is 10-20 years younger than that of the former. It is suggested that people younger than 50 years old with a family history of endometrial cancer or colon cancer should undergo genetic testing and genetic counseling; high risk groups with “familial hereditary tumors” such as Lynch syndrome and hereditary nonpolyposis colon cancer should be screened for hereditary endometrial cancer before the age of 40. Menopause and menopause are the high incidence period of endometrial cancer. Once irregular vaginal bleeding, bloody leucorrhea and other early symptoms appear, we should go to the hospital as soon as possible.
gastric cancer. Those who are over 40 years old and are first-degree relatives of patients with gastric cancer should have gastroscopy screening as soon as possible and regularly. Those who are very reluctant to accept gastroscopy can do serological screening such as serum PG test, HP antibody test, G-17 test, and then according to the above results, the risk score of gastric cancer can be evaluated. When the risk score was high / medium risk group, further gastroscopy was performed.
in addition, the family members of cancer patients need to judge whether their cancer risk is high or not, which is “multiple, rare and young”. Multiple means that one of the close relatives has multiple cancers, or more than one close relative has cancer; rare means that a close relative has very rare cancer, such as the male in the family who has breast cancer; young means that the relative is very young, such as under 30 years old. Those who have these conditions should check their genetic background and consider doing genetic mutation detection to detect the risk as soon as possible. Focus