Breast Cancer is one of the common
cancers that affect women. Breast cancer occurs due to uncontrolled growth of cells in
the breast. It can occur at any stage of life, but the risk increases as women get older.
Men can also develop breast cancer, but it is more prevalent in women as they are constantly
exposed to the growth-promoting effects of the female hormones estrogen and progesterone.
Breast Cancer in Women
Breasts are made of lobules and ducts; lobules (glands that produce milk) are connected
to ducts which carry milk to nipples. Breast cancer occurs when cells in the breast multiply
uncontrollably; it usually begins either in the cells of the lobules (Lobular carcinoma) or in the ducts (Ductal carcinoma). Breast cancer
can also form in the fatty and fibrous tissues of the breast.
In breast cancer, the cancerous cells invade into the lymphatic system that includes,
the lymphatic vessels which carries the lymph fluid, and the lymph nodes where the
fluid is filtered. This filtered fluid passes through the breast tissues and travels back
into the blood stream. Fluid drained out from lymph nodes located around the breast
is filtered of bacteria and other foreign materials before they can reach the bloodstream.
Breast cancer cells acquire the ability to break off from the initial tumour and travel
to other parts of the body. The presence of tumour cells in the lymph fluid which is
trapped in the lymph node is an indication that cancer has the ability to spread and is
a more aggressive type of breast cancer.
Breast cancer remains high in the list of cancers that are most prevalent among Indian women.
For breast cancer,as with most other cancer types, early detection leads to largely better
treatment outcomes in patients. This necessitates first an awareness about breast cancer.
Although awareness is increasing throughout the world, it is still at risk of being diagnosed
late due to many factors like lack of information regarding its symptoms, signs and follow-up
procedures, fear of cancerdiagnosis, family issues, undergoing alternative therapies, financial
issues, embarresment'among many others.
In the global scenario, breast cancer is the most common cancer among females,
making up a quarter of all cancer cases. Though compared to the western world,
the incidence of breast cancer is lower in India, the mortality continues to be on par.
Indian women also develop cancer a decade earlier than women in the Western
countries, this is a cause for concern since cancer among younger women also tends
to be aggressive.
According to reports, trend of urbanization has led to changes in lifestyle and
eating habits which can be related to higher incidence rate of breast cancer in
major cities across India. Cities with highest reported cases of breast cancer include
Thiruvananthapuram, Delhi, Chennai, and Bangalore. Over the course of four years
(between 2008 and 2012), a 14% increase in mortality rates due to breast cancer
has been observed in India that could be attributed to lack of breast cancer screening
program, diagnosis at advanced stage, and reduced access to well-equipped medical facilities.
How long can you live after being diagnosed with breast cancer?
Breast cancer includes a heterogeneous group of diseases that differ in pathological
features and which need to be evaluated to allow for a better prediction of survival.
Survival in a cancer patient refers to the amount of time taken from diagnosis till the
time of succumbing to the disease. A 5-year survival rate indicates the likelihood of
patient surviving for 5 years following the diagnosis of the disease, although they
may go on to live for many years after this. So if a disease has 50% survival rate,
it would mean that they are half as likely to survive for 5 years, as compared to
a person not affected by the disease.
The 5-year survival rate for breast cancer is closely related to the stage at which it
is diagnosed and treated. Stagel and stage II breast cancers have better survival
rate than cancers diagnosed at stage III or IV. Other characteristics that influence
the survival rate of cancer are whether it is localized (within the same organ that initiated),
regionalized (if they have spread to nearby tissue) and distant or metastasized
(meaning that cancer cells have migrated to different parts of the body). Localized
cancers exhibit the highest survival rate. The 5-year survival rate for breast cancer
in India is 4062%, much lower than what is seen in developed nations. Measuring
survival time for different cancer subtypes is important for evaluating the outcome
of the prescribed treatment. Studying the factors that influence survival rates can
help in improvement of treatment proposals and even define early detection actions.
How Does Breast Cancer occur?
Cancer occurs when cells undergo unregulated division to form a mass that may spread
to other parts of the body and interrupt normal physiological functions necessary for
survival. The breast is composed of two main types of tissues, glandular tissue and
stromal tissue. The stromal tissue consists of fatty and fibrous connective tissues
while the glandular tissue comprises of the milk producing glands (lobules) and the
milk ducts. In addition to these two types, breast also contains lymphatic tissue to
remove cellular waste. Breast cancer arises from tissues of the mammary gland, most
commonly from the inner lining of milk ducts or the lobules which provide the ducts with milk.
What is the tissue origin of breast cancer?
Breast cancer can originate in any of the cells of the mammary gland and based on this,
it can be classified into several types. If the tumor remains restricted to the ducts and
does not invade surrounding fatty tissue, it is called as non-invasive breast cancer.
The most common example of non-invasive breast cancer is ductal carcinoma in
situ (in situ meaning that the cancer has not spread past the site of origin).
If the tumor cells invade the surrounding fatty tissue, it is an invasive breast cancer type.
While most of the malignant breast cancers are carcinomas, different types of sarcomas
may also arise in the breast tissue.
Book CA 15.3 Cancer marker test
Breast Carcinomas
Adenocarcinoma constitute 95% of all breast cancers detected and can largely be
divided into Invasive Ductal Carcinoma (IDC) and Ductal Carcinoma In Situ (DCIS)
Ductal Carcinoma in situ (DCIS)-
Being a carcinoma, DCIS originates from the epithelial cells and remains limited to the
ducts or lobules, although it exhibits tendencies to develop into subsequent invasive
breast cancer. The risk of developing into invasive phenotype correlates with the grade
of DCIS, and may take many years. Risk of death from DCIS is low, but conversion to
invasive type which remains undetected is a cause for concern.
Infiltrating Lobular Carcinoma (ILC)-
ILC begins in the milk glands but subsequently spreads to other regions of the body.
Usually affecting older women, the incidence of ILC is reported to be on the rise particularly
among postmenopausal women, presumably due to hormone replacement treatments.
Lobular Carcinoma in situ (LCIS)-
In LCIS, tumor cells are small, uniform and loosely cohesive. Similar to DCIS, LCIS is non-invasive
but constitutes a risk factor for subsequent development of invasive type of breast cancer.
It can be distinguished by the absence of two proteins, E-cadherin and beta-catenin, which
are both present in DCIS.
Invasive Ductal Carcinoma (IDC)-
IDC is a malignant cancer in which ductal proliferation is accompanied by stromal invasion.
The most common type of breast cancer (80% of all breast cancer diagnoses)," IDC itself has
several subtypes based on tissue characteristics, architectural features and
immunohistochemical profile. These include:
- Tubular Carcinoma
- IDC no specific type (NST)
- Medullary Carcinoma
- Mucinous Carcinoma
- Papillary Carcinoma
- Cribriform Carcinoma
- Micropapillary Carcinoma
Other types of breast cancer include Paget's disease of the breast, inflammatory
breast cancer, Phyllodes tumor of the breast and metastatic breast cancer.
What are the risk factors for breast cancer?
Breast cancer has several risk factors, some among which can be managed while
others are predetermined.
Gender-
The major risk factor for developing breast cancer is gender; especially among females.
This means that breast cancer is also possible in males, but is far more common in women.
Age-
Risk of developing breast cancer increases with age,with the highest risk being in women
between 40 to 59 years of age (1 in every 26 women).
Reproductive Factors-
Several reports indicate reproductive factors like early menarche, history of breast diseases,
number of children,' late childbearing age, and a women's age at menopause (late menopause)
are associated with higher risk of breast cancer.
Family history-
Genetics plays a significant role in the risk for developing breast cancer. Having close
relatives that have suffered from breast cancer can indicate a greater likelihood
of developing the disease. Greater the number of family members who suffer from
cancer, higher the risk chances. Mutations in BRCA1 and BRCA2 genes can confer
as much as 40-85% lifetime risk of breast cancer.
Endangering Factors Obesity-
Obesity, especially among postmenopausal women has been reported to increase
risk of breast cancer. The risk of cancer increases proportionately with BMI and
hip circumference. This could be attributable to insulin resistance and high insulin
levels that are usually associated with obesity. Hyperinsulinemia is also reported
to be an independent risk factor for development of breast cancer.
Alcohol consumption-
Binge drinking has particularly been shown to influence the likelihood of developing
breast cancer.
Radiation exposure-
Radiation exposure can occur due to proximity to highly radioactive substances and
undergoing medical treatments. People who have gone through radiation treatments
for childhood cancers are at higher risk of developing breast cancer later in life.
Breast Cancer Episode
Breast cancer arises from complex interaction between genetic and environmental factors.
Cancer develops when cells are unable to check their growth and proliferate without control.
One of the pathways that prevents such a thing from happening is the pathway that activates
cell suicide (apoptosis). Mutations in the genes that are involved in this pathway can prevent
the cell from dying normally as it should and fueling growth tillit becomes a tumor. Other
pathway that can lead to development of breast cancer include growth factor signaling
pathways. An overexpression of growth factors signals the cell to grow uncontrollably.
Finally, some gene mutations have been detected to be involved in hereditary
breast-ovarian cancer syndrome. These include p53, BRCA1 and BRCA2, which are
involved in DNA repair that is essential for normal cell functioning and whose
disruption can lead to breast cancer.
What are the Symptoms and Signs of Breast Cancer?
Following are the Indicators of of Breast Cancer
- In case of inflammatory breast cancer, clinical presentation
includes itching, pain, warmth and redness of the breast, swelling as well as change
in texture of the skin. Paget's disease of the breast is a type of breast cancer accompanied
- Change in the nipple or nipple discharge
- Skin dimpling in the breast
- One breast being larger or lower than the other
- Constant pain in the breast
with discoloration, redness and flaking of nipple. Phyllodes tumor is characterized by
the presence of hard, movable lumps which comprises of both stromal and glandular tissue.
In case of metastatic cancer, if the cancer has spread to other regions like bone, liver, lung and
brain, symptoms can depend on the site of metastasis and include weight loss, chills, bone pain
and neurological symptoms.
Breast Cancer in Men
Breast cancer in men is rare. In spite of biological differences between male
and female, clinical outcomes on the basis of factors such as age, treatment,
and stage of cancer are similar to that in females. Breast cancer majorly affects
men of older age. Symptoms are painless lump or swelling behind the nipples,
swelling in the armpit and discharge from nipple. Risk factors includes family
history of breast cancer in his female relatives, gene mutation, radiation exposure,
etc. Diagnosis and treatment of cancer in men are similar to that of females,
which includes physical examinations, mammography, biopsies, etc.
Importance of Early Detection
Yes, early detection of breast cancer is the best defence because diagnosis
at initial stage makes them easier to treat and may save a life. It is important
to recognize the warning signs and take prompt action which can help in early
diagnosis. Size of cancer tumour and the extent of spread are the most important
factors that predict the prognosis of an individual. Breast cancer Surgery stages
range from level 0 to 4: Stage 0 and stage 1 are effectively treatable; chemotherapy
is considered for treatment. Stages 2, 3 and 4 involve aggressive treatments
like surgery and Chemotherapy radiation therapy. Individuals with stage 4 breast
cancer are considered to be less curable as tumour cells spread to other parts of
the body, but they can respond to treatm ents that helps extend your life by several
years. Early diagnosis also reduces risk of recurrence, as tumours in early stages do
not have a chance to spread to other areas.
Tests used to diagnose breast cancer includes
Mammogram
Mammograms provide X-ray pictures of the breast region that are
effective for finding tumours.
Breast ultrasound
A device that uses sound waves called sonogram to create detailed
pictures of tissue inside the breast.
Breast Magnetic resonance imaging
This machine uses a powerful magnetic field, radio waves and a computer to
produce detailed pictures of the structures within the breast.
blood tests
Includes BRCA gene detection in blood using DNA analysis to identify harmful
mutations in the breast cells.
Breast Biopsy
A test in which a needle device guided by X-ray is used to extract tissue from suspected
area. A small metal marker can be inserted at the site for further imaging test. Tissue
examination is done to determine whether the cells are cancerous.
What are the Pre-emptive Measures for Breast Cancer?
Screening and Mammography Diagnosis
Considering the dependence of breast cancer prognosis on the detection of the tumor at
an earlier stage,screening methods for breast cancer have gained importance in healthcare
today. In fact adeqate access to organized screening procedues for breast cancer in
the western nations is the western nations is believed to increase survival rates in
breast cancer patients as they are diagnosed at earlier stages." In India, there is a
lack of National or Regional breast cancer screening programs. Moreover, many rural
Indian women report emotional reasons in addition to practical ones behind avoiding
medical help. Nevertheless, at an individual level, screening for breast cancer is possible
through several means. Most of the detection of cancer is done at the stage where it
forms a palpable mass or causes chest wall changes. As a result, self-examination of
the breast is usually the first step in identifying the presence of a lump which may
indicate breast cancer. It also allows women to recognize their normal anatomy and
understand if MRI scans something is different from the usual.
Some masses that develop in the breast may be non palpable (cannot be detected by touch)
and these can be detected by mammography, therefore allowing early on the detection of
breast cancer. In mammography, X-ray pictures of the breast are taken which can help identify
the presence of masses, microcalcifications and other abnormalities of breast tissue.
MRI scans
MRI plays a crucial role in the detection, assessment, staging and management of breast cancer.
for screening .MRI us more sensitive dor detection of cancer in high risk women, although its
specificity is lower.
Ultrasound
Ultrasound is suggested for high risk patients who have dense breast tissue which can
cause false positives to appear in the screening.
In addition to the above, fine needle aspiration also helps to establish the diagnosis.
Biopsy includes either core biopsy or excisional biopsy in which the entire lump can be removed.
What is the first treatment for breast cancer?
Treatment for cancer is multifaceted, and the course of treatment(s) followed usually depends
on the nature of the cancer and the extent of its spread. For non-metastatic cancer, the primary
goal is eradication of the tumor and preventing cancer recurrence.
For non-metastatic cancers, systemic approach for treatment depends upon the
subtypeof cancer. This subtype is based on which receptors are present on the
surface of cancer cells. For instance, patients with ERBB2.positive (a cell surface
protein, also known as HER2) tumors receive ERBB2-targeted antibody or
smallmolecule inhibitor therapy, combined with chemotherapy. Cell surface
proteins are receptors which help distinguish different tumor types. Therefore
hormone receptor positive breast cancer is treated differently than negative
Local therapy for patients with non-metastatic cancers involve surgical removal
of the tumor followed by radiation treatment. Surgery is usually employed among
earlier stages of breast cancer that has not spread much from its initial site. It may
either be to remove the entire breast (mastectomy), or breast conserving surgery
(lumpectomy). In more advanced cancer stages, chemotherapy is done to shrink
the tumor prior to surgery.
Cancer diagnosis is one of hardest things in life one may have to face. While we
cannot control such aspects of our present or future, it is always prudent to be
armed with knowledge and awareness about them so we may catch these
conditions in their path at the earliest possible.
