Carcinoma breast etiology
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Transcript of Carcinoma breast etiology
ETIOPATHOGENESIS OF BREAST CANCER
By: Partha Pratim MandalMedical College kolkata
Risk Factors
• Alcohol drinking• Being overweight• Never having children• 1st child >30yrs of age• Hormone Replacement
therapy• Birth control pills• Being exposed to large
amounts of radiation• Smoking
Controllable
• Getting older• First degree relative with
breast cancer• A previous breast biopsy
showing atypical changes• Being young (<12) at the
time of menses• Starting menopause after
age 55• Having an inherited
mutation in the breast cancer genes (BRCA 1 or 2)
Uncontrollable
Age
The risk of getting breast cancer
increases with age
More common at middle age but can
occur at any age group after 20 years
A woman is likely to develop breast
cancer in her 60s than in her 20s
Age as a risk factor
By age 30 1 out of 2,000
By age 40 1 out of 233
By age 50 1 out of 53
By age 60 1 out of 22
By age 70 1 out of 13
By age 80 1 out of 9
Lifetime risk 1 out of 8
Gender
Breast cancer occurs nearly 100 times more often in women
than in men.
In a few African countries, which represent the highest
incidence of male breast cancer, men account for 5–15% of
breast cancer cases
Because awareness among men is less and they are less likely to assume a lump is breast cancer,
which can cause a delay in seeking treatment.
Family History and Genetic Factors
Only 5-10% of breast cancers are inherited.
Families that do have genetic defects in one of two genes, breast cancer gene 1 (BRCA1) or breast cancer gene 2 (BRCA2), have a much greater risk of developing both breast and ovarian cancer.
BRCA1 & BRCA2 MUTATION
Both BRCA1 (located on long arm of chromosome 17) & BRCA2 (located on long arm of chromosome 13) function as a tumor suppressor genes, and for each genes loss of
both alleles is required for the initiation of cancer.
BRCA1 having more risk(35%-45%) than BRCA2 mutation.
Commonest mutation of BRCA1 are 185delAG & 5382insC
HER2 OVEREXPRESSION
HER2. Amplification or overexpression of this oncogene increase development and progression of certain aggressive
types of breast cancer.
It is located at the chromosome 17q12.
Other genes mutation
Occasionally mutation of BRCA3 & p53suppressor also involved.
Non-BRCA1 and non-BRCA2 breast tumors may be associated to rare syndromes, of which breast cancer is only one component. Such syndromes result notably from mutations in TP53 (Li-Fraumeni syndrome), ATM (Ataxia Telangiectasia), PTEN (Cowden syndrome)
RAB11FIP1, and rs4973768 are also associated with increased risk of breast cancer. rs6504950 is associated with lower risk of breast cancer
Early menstruation. Risk increases if
menstruation begin before age 12.
Late menopause. Menopause after age 55, increases
risk.
HORMONESEstrogen. Persistently increased blood levels
of estrogen are associated with an
increased risk of breast cancer.
estrogen does not appear to directly cause
the DNA mutations
Controllable Risk factors
Weight. Being overweight, with excess caloric and fat intake, increases risk, especially after menopause due to conversion of androstenedione to
estrone by adipose tissue.
Age at childbirth. Having first child after age 35 or never having children
increase risk.
Dietary factors
Alcohol. Consumption of alcohol is linked to increased risk of developing breast cancer. Consume 2 to 5 drinks daily have about 1.5 times risk.
Fat . Low fat diet may significantly decrease the risk of breast cancer as well as the recurrence of breast cancer.
Calcium. A high dietary intake of calcium lower the risk of breast cancer.
Dietary factors
Vitamin D. Vitamin D is related to reduced risk of breast cancer and disease prognosis.
Specific dietary fatty acids. Very high consumption of omega-6 fatty acids (PUFAs) increase the risk breast cancer in postmenopausal women.
Hormonal contraception. Hormonal contraceptive with estrogen content may produce a slight increase in the risk of
breast cancer. women who began using hormonal contraceptives before the age of 20 or before their first full-
term pregnancy are at increased risk for breast cancer
Hormone replacement therapy. Taking combined hormone replacement therapy, as prescribed for menopause, can
increase your risk for breast cancer and increases the risk that the cancer will be detected at a more advanced stage.
Selective estrogen receptor modulators (SERMs). they selectively stimulate or inhibit the estrogen receptors of
different target tissues.
Factors in the physical environment
Tobacco. Exposure to tobacco smoke is most problematic between puberty and first
childbirth . The reason is that breast tissue appears most
sensitive to chemical carcinogens breast cells not fully differentiated
until lactation
Passive smoking. it increases breast cancer risk by 70% in
younger, primarily pre-menopausal women.
Radiation. Women who have received high-dose radiation to the chest have a relative risk of breast
cancer between 2.1 to 4.0.Radiation exposure during
adolescence, magnifies deleterious effect.
Factors in the physical environment
Ethylene oxide. A direct correlation between breast cancer rates and exposure to ethylene oxide during medical sterilization processes.
Benzene. High level of benzene exposure can lead to mammary cancer.
DDT. Exposure to DDT before puberty increases the risk of breast cancer later in life.
Factors in the physical environment
Dioxins. Dioxin level exposure in a woman's body correlated with a
more than double chance of developing breast
cancer.
Aromatic amines. More exposure to heterocyclic amines, have also been diagnosed with more
post-menopausal breast cancer.
Polycyclic aromatic hydrocarbon. PAH's
bioaccumulate easily and can copy the estrogen hormone & they have
the ability to harm DNA
Factors in the physical environment
Xenoestrogens . Increasing prevalence of these substances in the environment may explain the increasing incidence of breast cancer
Light at night & disturbance of circadian rhythm. Artificial light during the night can be a factor for breast cancer by disrupting melatonin levels
RACIAL FACTORS
White women are more likely to be diagnosed with the disease.
Black women are more likely to have estrogen receptor negative breast cancers.
Mortality higher among black women.
Factors with minimal impact
Abortion. First-trimester abortion increases the risk of developing breast cancer.
Deodorants. Aluminum-containing underarm antiperspirants underarm increased risk of breast cancer .
Viruses. Human papilloma virus, human cytomegalovirus and the Epstein-Barr virus are suspected to play a role or cause breast cancer
Factors with inconclusive research
Tea. moderate green or black tea consumption (three or
more cups per day) can reduce breast cancer risk.
Mammographic density. High mammographic density is
associated with a higher risk of developing breast cancer.
Red no 3. human breast cell DNA was found positive for
damage when put into contact with Red No. 3
Mammographic density
Thank you……