The pink ribbon is a global symbol for breast cancer awareness. Image credit: Freepik
The pink ribbon is a global symbol for breast cancer awareness. Image credit: Freepik

Breast cancer is a type of cancer that happens when a malignant tumor grows in the breast tissue. The tumor develops when the genes responsible to regulate healthy breast cell growth get mutated or subjected to abnormal changes, resulting in damage to the cells. Cells are constantly being produced in our bodies to replace dying cells. When the multiplying cell is mutated, more abnormal cells are produced, which come together to form a tumor.

Breast cancer is a type of cancer that predominantly affects women. In fact, breast cancer is the second most commonly occurring cancer in women, after skin cancer. Though rare, breast cancer could also affect men who have high estrogen levels or a familial cancer history. Like all other cancer types, breast cancer is not contagious, meaning it cannot spread from an affected lady to a healthy woman. Also, the cancer isn’t caused by breast implants, underwire bras, mammograms, antiperspirants, plastic items used to serve food, caffeine, cell phones, and/or microwave.

Tumor Types

Breast cancer tumor could be of two types: benign or non-cancerous, and malignant or cancerous. A benign tumor is usually left untouched. If the tumor grows or causes pain, it could be surgically removed. A malignant tumor is comparatively more aggressive and dangerous since it invades and damages surrounding tissues. When people talk breast cancer, they’re actually referring to the malignant tumor.

Tests are usually carried out to determine a malignant tumor’s aggressiveness or severity. When a malignant tumor’s cancer cells break away and spread to another part of the body and form a fresh tumor, the result is metastatic cancer. This cancer type usually spreads to the bones, lungs, brain or liver.

Cause and Growth

Image credit: Flickr
Image credit: Flickr

The exact reason why breast cancer happens is still not clear. This is why preventing breast cancer is so difficult. It’s clear how the cancer happens, which is through a damage to the breast cell’s DNA, but it’s not clear what led to that damage. The cancer grows when the damaged or cancer cells replicate themselves, contributing to tumor growth and making more damaged cells in the process. The damaged cells may seem to replicate at a much quicker rate than healthy cells. But in reality, damaged cells do not stop making copies of themselves. Contrarily, the healthy cells stop recreating themselves once they have created a tissue.

Breast cancer is inherited to a certain extent, but it’s not the major reason why women develop the cancer. In fact, only 5-10 percent breast cancer cases are inherited. The primary reason behind breast cancer is the gene-level abnormalities that occur with age and general life progression. Since “age” is such a broad term, it isn’t possible to accurately determine the cause(s) of breast cancer.

In case of a genetic predisposition, the individual inherits the mutated form of the BRCA1 or BRCA2 gene. BRCA stands for (BR)east (CA)ncer. Both genes are human caretaker genes or genes that suppress tumor. The mutation happens when the DNA making up the gene is damaged somehow. After mutation, the gene is no longer capable of carrying out its function. If one of the parents has a mutated BRCA gene, there’s a 50 percent chance of the mutated gene transferring to the offspring.

There are other tumor suppression genes which if mutated could also lead to the cancer: PALB2, CHEK2, CDH1, PTEN, STK11, and TP53. A very small percentage of the human population carries the BRCA1 or BRCA2 mutated gene.

Signs & Symptoms

Breast cancer signs. Image credit: Wikimedia Commons
Breast cancer signs. Image credit: Wikimedia Commons

Usually, other than the lump itself, there aren’t much breast cancer symptoms or signs. Moreover, not all breast cancers cause a breast lump. However, there are some signs that may denote breast cancer – including nipple redness or discharge, changes in breast skin such as dimpling or puckering (wrinkling), inverted nipple, bloody nipple discharge, sore nipple or breast pain, changes in the shape or size of the nipple or breast, etc. The areola or the colored area surrounding the nipple could peel, scale or flake.

Breast Cancer Stages

There are different breast cancer stages, and knowing what stage you’re in helps devise the treatment and other strategies to contain the disease. Basically, the different stages are defined by the breast tumor size, number of affected lymph nodes, and signs of the cancer’s spread to other body parts. There are several signs that may indicate a particular stage. To be diagnosed with a particular stage of cancer, one need not exhibit all the signs.

Stage 0

Also referred to as carcinoma in situ, stage 0 is not cancer, even though there’s “carcinoma” in the name. The stage basically signals the proliferation of abnormal yet non-invasive cells within the lobules. However, it indicates a woman has the risk of getting breast cancer. Most stage 0 breast cancers do not require treatment. And even if they do, the outcome is usually successful. There are two stage 0 breast cancer types: ductal carcinoma in situ (DCIS), and lobular carcinoma in situ (LCIS). As the names indicate, DCIS is when the cancer grows in the ducts, and LCIS is the cancer cells developing in the lobules.

Stage I

This breast cancer stage indicates the cancer is minor and has affected only the breast tissue or lymph nodes near the breast. Stage 1 breast cancer can be further categorized as stage 1A and stage 1B. Stage 1A basically means the tumor isn’t larger than 2 cm and is within the breast. Stage 1B breast cancer cells are also not more than 2 cm in size; however, the cells could be located in the lymph nodes near the breast.  The treatment for stage I cancer is surgery where the cancerous spot with a normal breast tissue’s border is removed. Post-surgery, radiotherapy is administered for several weeks to other portion(s) of the breast.

Stage II

Also subdivided as stage 2A and stage 2B, stage II breast cancers are invasive in nature where the tumor size can be anywhere between 2 and 5 cm, or even less than 2 cm. Stage 2A means there are no cancer cells in the breast but they could be found in 1-3 lymph nodes near the breastbone or beneath the arm. Stage 2A cancer tumor could be smaller or larger than 2 cm but not more than 5 cm in diameter. Stage 2B could mean the tumor is more than 2 cm in size and larger or not larger than 5 cm.

Stage III

In stage III breast cancer, the tumor generally has a diameter of more than 2 inches (5 cm). This stage can be categorized as stage 3A, stage 3B and stage 3C. Stage 3A could mean no cancer tumor in the breast, but in the lymph nodes (four to nine nodes) near the breastbone or under the arm. The tumor could be found in the breast also, measuring up to 5 cm in diameter. Stage 3B means the cancer could be of any size, and the tumor has extended to the chest or breast wall’s skin. The cancer could be found in nine lymph nodes (maximum) near the breastbone or beneath the arm. All stage 3B traits apply to stage 3C. The only exception being the total number of lymph nodes affected could go up to 10.

Stage IV

Stage 4 is the advanced stage and it means the cancer has affected other body parts such as bones, brain, liver and lung. The tumor size cannot be predicted and the cancer cells may or may not be in the lymph nodes. Also called metastatic or secondary breast cancer, the chances of surviving stage 4 breast cancer is almost zero, but excellent care and treatment could still offer a ray of hope. The treatment choices for the affected individual could vary based on her location and how accessible the medical facilities/specialists are.

Invariably, the patient would have to undergo therapies that still are in their experimental phase, provided she is willing. The treatment would be devised based on past treatments, the cancer’s spread, speed at which the cancer is growing, and other health issues (if any). Usually, the treatment begins with therapies with the least side effects. Hormone therapy is commonly used to treat stage 4 breast cancer. Radiotherapy is resorted to if the bones, brain, and breast or mastectomy-scarred skin have been affected. Chemotherapy is also likely.

Breast Cancer Types

There are different kinds of breast cancer, which are primarily characterized by the abnormal breast cells that multiply uncontrollably. Breast cancers can be categorized based on their origin, growth, impact, and occurrence or rarity. Broadly speaking, a breast cancer can be invasive or non-invasive.

Also called infiltrating breast cancer, an invasive breast cancer entails cancerous cells breaking through normal barriers of the breast tissue and spreading to other body parts via the lymph nodes and bloodstream. Lymph nodes are bean-shaped glands that, along with other lymph system organs, play an important role in the transport of nutrients and waste materials in the body. Unfortunately, most breast cancers are of the invasive type. In the case of non-invasive cancers, the cancerous cells stay in a particular breast location, such as the lobules or ducts, and do not spread to other body parts.

At times, the person inflicted with the cancer could have both non-invasive and invasive cancer cells. This means a portion of the breast cancer has remained within the milk lobules or milk ducts. Such cases, however, would be considered as invasive cancer. A breast cancer could also be “mixed tumor”. This means it would comprise a variety of cancerous lobular (milk lobules) and ductal cells (milk ducts). This cancer type is referred to as “infiltrating mammary carcinoma” or “invasive mammary breast cancer”.

In case there are multiple tumors, the breast cancer would be referred to as either ‘multi-centric’ or ‘multifocal’. A multifocal breast cancer would entail tumors arising from the tumor that occurred first, and all would invariably reside in the same breast section. If the cancer type is multi-centric, it indicates all the tumors were formed individually and are usually in different sections of the breast.

The following is a brief introduction to the different non-invasive and invasive breast cancers:

  • Ductal carcinoma in situ (DCIS) is the uncontrolled cell growth inside the breast ducts. It’s the earliest and common non-invasive breast cancer type that doesn’t spread and is therefore easier to treat or cure.
  • Also called infiltrating ductal carcinoma, invasive ductal carcinoma (IDC) is a type of invasive breast cancer where the cancer has grown inside the breast’s duct and has then spread to the breast’s fatty tissue outside the duct.
  • Also referred to as lobular neoplasia, lobular carcinoma in situ (LCIS) indicates a region or multiple regions with abnormal cell growth, which increases the possibilities of being diagnosed with invasive breast cancer in the future. Technically, LCIS is not cancer.
  • Representing close to 10 percent of all invasive breast cancers, invasive lobular carcinoma (ILB) is most likely to affect both breasts compared to other breast cancer types.

The following are the rare breast cancer types:

  • Inflammatory breast cancer is a rare breast cancer type that begins in the breasts’ soft tissues and blocks the breast skin’s lymph vessels.
  • Male breast cancer develops the same way as breast cancer in women – the only difference being a man is the victim here.
  • Also called advanced or stage IV breast cancer, metastatic breast cancer is a type of breast cancer which spread its wings to other body parts or organs.
  • Named after an English doctor, Sir James Paget, Paget’s disease of the breast or nipple where cancer cells accumulate near or in the nipple, causing noticeable changes to the nipple’s skin.
  • Also called colloid carcinoma, mucinous carcinoma is formed courtesy the mucus-making cancer cells in the breast.
  • Phyllodes tumors of the breast essentially indicate the tumor cells are growing in the shape or pattern of a leaf. The tumors grow quickly, but rarely move outside the breast.

Certain breast cancers could be caused due to the breast cancer cells’ genetic makeup or their sensitivity to the female body’s naturally occurring hormones such as estrogen and progesterone. These cancer cells come with receptors on the exterior of their walls that could trap certain hormones circulating through the body.

  • HER2-positive is an invasive breast cancer that happens when too many HER2 (human epidermal growth factor receptor 2) cells or genes are made, resulting in the production of excessive HER2 receptors.
  • Luminal A is a breast cancer type comprising tumors that are estrogen receptor (ER) positive and progesterone receptor (PR) positive, but HER2 negative. In other words, the cancer is sensitive to both estrogen and progesterone. Hormone therapy and chemotherapy are ideal treatment methods for this breast cancer type.
  • Luminal B entails tumors that are ER positive, HER2 positive, and PR negative. Chemotherapy and hormone therapy could help treat the condition.
  • An invasive breast cancer type, triple-negative starts in breast ducts. Also referred to as basal-type, the cancer cells don’t comprise estrogen, HER2, or progesterone receptors. Generally, chemotherapy is quite effective at treating this cancer type.

This list of the different types of breast cancer is not exhaustive by any means. With ongoing research in the medical field, new variants of the cancer may get discovered and classified. The aforementioned cancer types are universally recognized.

Risk Factors

Before we get on with the risk factors, it’s important to understand that a risk factor doesn’t mean the person is guaranteed to be diagnosed with breast cancer in the future. It only indicates the chances are higher. There are women with high risk factors who do not develop breast cancer at all. Similarly, there are ladies who never had the risk factors but fell victim to the cancer.

Personal/family history: A family or personal history of breast cancer is a likely risk factor. If one of the breasts have been previously diagnosed with cancer, the risks of the other breast developing the cancer are high. Moreover, the same breast could get diagnosed with another cancer.

Dense breast tissue: Women with dense breast tissue have a higher breast cancer risk.

Alcohol: Alcohol could alter how a female body metabolizes estrogen or the female hormone’s work mechanism within the body. This could cause the estrogen levels in the blood to go up, which is why estrogen levels tend to be higher in ladies who consume alcohol compared to estrogen levels in non-drinking females. The higher estrogen levels could in turn increase breast cancer risks.

Longer menstrual cycle: Early period and late menopause mean a slightly higher chance of breast cancer, thanks to their increased estrogen levels. Generally, the onset of a period at or before 12 years of age is considered early.

Late pregnancy: Having kids after 30 years of age also increases breast cancer risks. Having not been pregnant before could also heighten risks of breast cancer.

Postmenopausal hormone therapy: Women on hormone therapy medicines, which combine progesterone and estrogen to treat menopause symptoms and signs, are vulnerable to breast cancer.

Overweight: Obesity could also increase breast cancer risks.

Age: As aforementioned, increasing age is another reason why you may develop breast cancer.


Breast cancer diagnosis is done with a physical test, breast self-examination, ultrasound testing, biopsy, breast magnetic resonance imaging (MRI) and mammography. A breast exam entails the physician checking both the breasts and the armpit lymph nodes for lumps or abnormalities. A mammogram is basically the breast’s X-ray. Mammography can help detect the cancer before the symptoms could show up, but it may also miss some cancers, which doesn’t make mammography a foolproof technique. Ultrasound helps conjure pictures of structures situated deep inside the body.

A biopsy is more invasive, which entails removal of some breast cells for examination. A biopsy is the most definitive or conclusive method to diagnose breast cancer. The breast MRI technique helps create pictures of the breast’s interior. Not all affected women would require to undergo all these tests. The doctor chooses the right tests depending on individual circumstances and symptoms.


The treatment for the cancer is basically dependent on the cancer type and stage, size, and the cancer cells’ sensitivity to hormones. The patient’s general health and treatment preferences are also considered before zeroing in on a specific treatment type. Most women affected by breast cancer undergo surgery, with additional treatment received after or before surgery, which could be hormone therapy, radiation, targeted therapy or chemotherapy.

Hormone therapy: Hormone therapy entails medications that either prevent hormones from sticking to the cancer cells or stop the body from producing estrogen after menopause. It is basically carried out to decrease cancer reoccurrence risks post-surgery.

Radiation: Radiation therapy is usage of high energy rays to destroy cancer cells. The treatment could entail an external radiation beam focusing on the affected region. The need for such radiation is determined based on the type of breast cancer surgery, and which is provided five days every week for at least five weeks and not more than six weeks. Brachytherapy is an alternative technique that delivers radiation using radioactive pellets or seeds, which are implanted within the breast close to the cancer.

Chemotherapy: The therapy is a treatment that entails administering drugs that can access the cancer cells via the bloodstream. The medicines could be given orally or as injections.

Targeted therapy: This therapy is basically a type of chemotherapy that can differentiate between normal and cancer cells. Chemotherapy, on the other hand, could also kill normal cells, which is why the side effects of a chemotherapy are so dramatic.

The breast cancer operation could be lumpectomy (removal of the cancer), mastectomy (removal of the entire breast), sentinel node biopsy (removal of a few lymph nodes), axillary lymph node dissection (removal of many lymph nodes), or removal of both breasts. A breast cancer surgery is not just painful and bloody, but could also be infectious and lead to lymphedema (swelling of the arm). Most women after having done the breast cancer surgery opt for a breast reconstruction surgery.


If the risk factors, such as mutated genes, are detected and treated early, breast cancer can be prevented from developing. Preventive surgery is an extreme option that some women consider to not let the cancer develop at all. The surgery entails removal of one or both breasts, or part(s) of the breasts. Exercise helps lower breast cancer risk since it helps balance the body’s estrogen level and reduce weight.

Breast Cancer and Pregnancy

Breast cancer’s magnitude or aggressiveness isn’t much different from a non-pregnant woman with breast cancer. Most importantly, the cancer would not get transmitted to the baby. But breast cancer detection in a pregnant woman happens at a fairly advanced stage. Pregnant women usually have lumpy and large breasts, which make it difficult to discover fresh lumps in the breasts. As far as treatments are concerned, mastectomy, needle biopsies, scans, etc. are perfectly fine to discover and treat breast cancer in pregnant women. However, radiotherapy and chemotherapy must be avoided since the treatments could adversely impact the growing baby, particularly when the treatment is administered in the initial three months.