Hereditary Breast-Ovarian Cancer Syndrome
Introduction
Introduction to hereditary breast cancer-ovarian cancer syndrome In families with hereditary breast cancer, breast cancer patients or their first or second blood relatives have two or more ovarian cancer patients, this family belongs to the hereditary breast cancer-ovarian cancer syndrome family, 20th century In the literature of the first epidemic of ovarian cancer in the 1950s, Lynch first described breast-ovarian cancer syndrome in 1972, and defined three distinct hereditary ovarian cancer syndromes in 1992: 1 hereditary non-polyposis Colorectal cancer syndrome (ie Lynch type II). 2 genetic site-specific ovarian cancer syndrome. 3 hereditary breast cancer - ovarian cancer syndrome. The latter is the most common of the three syndromes. basic knowledge The proportion of sickness: 0.00012% Susceptible people: women Mode of infection: non-infectious Complications: ovarian cancer, breast cancer
Cause
Hereditary breast cancer - the cause of ovarian cancer syndrome
(1) Causes of the disease
Hereditary breast cancer-ovarian cancer syndrome is an autosomal dominant inheritance with variable genetic appearance. In 1991, Narod et al confirmed the susceptibility gene of hereditary breast cancer-ovarian cancer and further mapped the gene to 17q12. 23, in 1992, the gene was named BRCA1. The International Breast Cancer Interlocking Group confirmed the relationship between BRCA1 and hereditary breast and ovarian cancer, and limited the BRCA1 gene to 17qD17S25017S588. In July 1994, the Skolnick research group The member completed the localization and cloning of BRCA1. BRCA1 is located at 17q17S1321~D17S1325 and consists of 22 coding exons. It occupies 100kb of genomic DNA, transcript 7.8kb, encoded protein contains 1863 amino acids, and the zinc finger structure of the amino terminus of BRCA1 protein exists. , suggesting a transcriptional regulatory function.
(two) pathogenesis
Clear hereditary breast cancer-ovarian cancer syndrome is mainly composed of serous cystadenocarcinoma in pathological classification. The role and regulation mechanism of BRCA1 in tumorigenesis is still not clear. It is considered that BRCA1 is a tumor suppressor gene. It encodes a tumor suppressor protein, which regulates tumor growth and inhibits tumor growth. However, most early-onset familial breast cancer and ovarian cancer have BRCA1 germ cell gene mutations. BRCA1 carriers develop breast at 50 years old. The risk of cancer and ovarian cancer is 73% and 29%, respectively. Those with BRCA1 gene, when they have oncogene mutations and decreased BRCA1 expression, have a higher risk of breast and ovarian cancer, and are also prone to occur. Class-related cancer.
The actual BRCA1 expression in the East and West population, different geographical factors and ethnic factors, and sex hormones, ovarian tissue and cell growth, development and differentiation are also directly related, so there is a need for further in-depth research.
Prevention
Hereditary breast cancer - prevention of ovarian cancer syndrome
The BRCA1 gene has a large structure, which makes the screening work quite cumbersome. At present, a variety of screening techniques have been combined, such as single-strand conformation polymorphism analysis, gradient gel electrophoresis, heteroduplex nucleic acid molecule determination, chemical cleavage mismatch , Allele-specific oligonucleotide hybridization, protein truncation assay and direct sequencing were applied to the detection of BRCA1 mutation.
Cancer surveillance: Family members with hereditary breast-ovarian cancer syndrome need to have lifelong cancer surveillance. The monitoring includes:
From the age of 118 to 21, the breast self-test is performed once a month; from 25 to 35 years old, the mammary gland is examined by a clinician every year or once every six months; from the age of 25 to 35, the breast is taken once a year.
Pelvic examination, vaginal ultrasonography, serum CA125 determination, color flow Doppler observation of ovarian blood flow from 225 to 35 years old.
Complication
Hereditary breast cancer - complications of ovarian cancer syndrome Complications ovarian cancer
Infection, tissue adhesion.
Symptom
Hereditary breast cancer - ovarian cancer syndrome symptoms Common symptoms Breast mass chest pain abnormal uterine bleeding fatigue
An important feature is that the onset age is early, and according to its definition, the syndrome is manifested as: in a family with a predisposition to breast cancer, two or more ovarian cancer patients with breast cancer patients or their class 1 or 2 blood relatives, and Has the following clinical features:
1 family of breast cancer showed early onset, the general age of onset <50 years;
2 The age of onset of ovarian cancer in the family is also earlier, generally 49.6 to 55.3 years old, with an average age of 52.4 years (the average age of onset of sporadic ovarian cancer is 59 years);
3 families may have other types of cancer patients, such as endometrial cancer, digestive tract cancer, prostate cancer, etc.;
4 The pathological type of ovarian cancer is more common in serous papillary cystadenocarcinoma.
Diagnostic points:
1 detailed family tree analysis, the complete medical records of the family should include the age of onset of malignant tumors such as ovarian cancer, breast cancer, colon cancer, endometrial cancer, pathological reports or death certificates.
2 The age of onset is early, most of the breast cancer is <50 years old, and the average ovarian cancer is 52.4 years old.
3 clinical features of breast and ovarian cancer.
The detection of 4BRCA1 and BRCA2 mutant genes was positive.
Because ovarian cancer is deep in the pelvic cavity, the lesion is not easy to be detected early. Once the cancer grows, the cancer is also growing rapidly. There is no effective early diagnosis method. For example, if the BRCA1 screening can be performed for those with a hereditary family history, the ovarian cancer will be detected early. Waiting for help.
Examine
Hereditary breast cancer-ovarian cancer syndrome examination
1. Vaginal ultrasonography can measure the size and shape of the ovary. Women with HBOCS tend to find ovarian enlargement, which should be paid attention to. If necessary, timely laparoscopic examination and biopsy to detect ovarian cancer early, vaginal ultrasonography is found to be smaller. Asymptomatic ovarian neoplasms are more sensitive.
2. Color Doppler ultrasound blood flow measurement of blood flow after ovarian blood supply, help identify ovarian benign and malignant tumors, mainly to measure the pulse index (PI), with a PI value of 1.0 as the boundary, if less than the value suggests malignant .
3. Serum CA125 determination of ovarian epithelial cancer, especially ovarian serous carcinoma, more than 80% of CA125 increased (>35U / ml), late 90% increased, it is generally recommended to test serum CA125 once a year to improve The rate of discovery of ovarian cancer in women with HBOCS tendencies.
Histopathological examination showed that the mutant genes BRCA1 and BRCA2 were positive.
Diagnosis
Diagnosis and diagnosis of hereditary breast cancer-ovarian cancer syndrome
Intrinsic should be differentiated from non-hereditary positive family history of breast cancer, ovarian cancer, and these families may have scattered breast cancer, ovarian cancer patients, but do not meet the characteristics of hereditary breast cancer-ovarian cancer syndrome, BRCA1 or Most of the BRCA2 mutations were negative.
