What is Breast Cancer? A Complete Guide for Patients and Families

Breast cancer is the most commonly diagnosed cancer among women worldwide, and can also affect men. The good news is that early detection of breast cancer offers a nearly 100 percent 5‑year survival rate. Unfortunately, many people delay screenings or dismiss warning signs such as unexplained skin dimpling or changes in nipple appearance, which leads to delayed diagnoses, narrowing treatment options and affecting care outcomes. In this blog, we’ll explain what breast cancer is, who is at risk, the symptoms to watch for, diagnostic and treatment approaches, and simple steps to lower the risk. Let’s start with the basics. 

What is Breast Cancer?

Breast cancer is a type of cancer that starts when cells in the breast begin to grow abnormally. These cells can multiply quickly and form a lump or mass, which may be felt during a physical exam or seen on an imaging test. In many cases, the cancer begins in the milk ducts (ductal carcinoma), but it can also start in the lobules (lobular carcinoma) or other parts of the breast.

It can spread beyond the breast to nearby lymph nodes and, in advanced stages, to other parts of the body such as the bones, liver, or lungs. This process is known as metastasis.

Breast cancer affects both women and men, though it is far more common in women. Risk factors include age, family history, certain genetic mutations (like BRCA1 and BRCA2), and lifestyle habits.

What are the Types of Breast Cancer?

Breast cancer can be classified into different types based on where it starts, how it behaves, and whether it responds to certain hormones. The two main categories are non-invasive (in situ) and invasive breast cancers. Here's a breakdown:

1. Ductal Carcinoma In Situ (DCIS)

Ductal Carcinoma In Situ (DCIS) is a non-invasive or pre-invasive form of breast cancer. It begins in the cells lining the milk ducts and stays confined there, meaning it hasn’t spread to nearby breast tissue. Although not immediately life-threatening, it can turn into invasive cancer if left untreated. It is often detected during routine mammograms.

2. Invasive Ductal Carcinoma (IDC)

IDC is the most common type of breast cancer, accounting for about 70–80% of all cases. It starts in the milk ducts and breaks through into the surrounding breast tissue. From there, it can spread to lymph nodes and other parts of the body. Symptoms may include a lump, nipple discharge, or changes in breast shape.

3. Invasive Lobular Carcinoma (ILC)

ILC begins in the lobules, which are the glands that produce milk. Like IDC, it is invasive and can spread to nearby tissues and other organs. It can be harder to detect through imaging because it tends to grow in a more scattered pattern, without forming a distinct lump.

4. Inflammatory Breast Cancer (IBC)

IBC is a rare and aggressive form of breast cancer. Instead of forming a lump, it causes the breast to become red, swollen, and warm due to cancer cells blocking lymph vessels in the skin. The skin may look pitted, like an orange peel. It tends to spread quickly and requires urgent treatment.

5. Triple-Negative Breast Cancer (TNBC)

This type of breast cancer does not have oestrogen receptors, progesterone receptors, or excess HER2 protein. As a result, it doesn’t respond to hormone therapy or HER2-targeted drugs. TNBC tends to grow and spread faster than other types and is more common in younger women and those with BRCA1 gene mutations.

6. HER2-Positive Breast Cancer

This cancer has high levels of HER2 protein, which encourages cancer cells to grow. HER2-positive cancers tend to be more aggressive but often respond well to targeted therapies. Early diagnosis improves outcomes significantly.

7. Hormone Receptor-Positive Breast Cancer

These cancers grow in response to hormones such as oestrogen (ER-positive) or progesterone (PR-positive). They are among the most common types and often have better treatment outcomes, as they can be managed with hormone-blocking medications like tamoxifen or aromatase inhibitors.

8. Paget’s Disease of the Nipple

This rare form of breast cancer starts in the milk ducts and spreads to the skin of the nipple and areola. It may cause symptoms like redness, flaking, itching, or discharge. It is often associated with DCIS or IDC deeper within the breast.

9. Phyllodes Tumours

These are rare connective tissue tumours that develop in the breast’s stromal (supportive) tissue. They can be benign, borderline, or malignant. Phyllodes tumours tend to grow quickly and may require surgical removal, even if they’re not cancerous.

10. Male Breast Cancer

Although rare, men can develop breast cancer, most often in the form of invasive ductal carcinoma. Risk factors include age, family history, and genetic mutations. Because breast cancer in men is often diagnosed at a later stage, awareness is crucial for early detection.

What Causes Breast Cancer and Who is at Risk?

Breast cancer develops when cells in the breast grow uncontrollably and form a tumour. In most cases, the exact cause of this uncontrolled growth isn’t fully understood. However, research shows that breast cancer results from a combination of genetic, hormonal, and environmental factors.

Genetic Mutations

Some breast cancers are caused by inherited changes in specific genes, especially BRCA1 and BRCA2. These mutations interfere with the body’s ability to control cell growth, which can lead to cancer. People with a family history of breast or ovarian cancer are more likely to carry these gene mutations.

Hormonal Influence

Oestrogen and progesterone play an important role in breast development, but prolonged exposure to these hormones may increase cancer risk. This can happen due to early periods, late menopause, or long-term hormone therapy after menopause.

Age-Related Cell Damage

The risk of cell damage increases with age. Over time, changes build up in breast cells, and some of these can lead to cancer. This is one reason breast cancer is more common in older individuals.

Lifestyle and Environmental Factors

Certain behaviours and exposures may contribute to cancer risk. These include alcohol intake, being overweight, smoking, low physical activity, and exposure to radiation to the chest.

Previous Breast Conditions

A history of breast cancer or certain non-cancerous breast changes, such as atypical hyperplasia, can increase the chance of developing breast cancer again.

Certain lifestyle and environmental factors may further increase the risk. These include alcohol use, obesity (especially after menopause), smoking, limited physical activity, and prior radiation exposure to the chest. A personal history of breast cancer or some non-cancerous breast conditions, such as atypical hyperplasia, also makes a future diagnosis more likely.

Other factors that may increase the risk include:

• Age above 50
• Family history of breast or ovarian cancer in a close relative
• Inherited BRCA1 or BRCA2 gene mutation
• Dense breast tissue
• Starting menstruation before age 12
• Menopause after age 55
• Having the first child after age 30 or not having children
• Long-term use of hormone replacement therapy
• Previous radiation therapy to the chest
• Alcohol consumption
• Physical inactivity
• Smoking

Although these factors raise the chance of developing breast cancer, not everyone with one or more of them will get the disease. 

What are the Signs and Symptoms of Breast Cancer?

Breast cancer does not always cause noticeable symptoms in its early stages. However, as it develops, certain physical changes may become visible or felt. Paying attention to these signs and reporting them early can help improve outcomes. Some of the most common symptoms include:

• Breast or underarm lump: A firm or hard mass that may feel different from the rest of the breast tissue. It might be fixed in place or move slightly under the skin. These lumps are usually painless but should always be evaluated.
• Change in breast size or shape: One breast may appear larger, fuller, or differently contoured compared to the other. This change may happen gradually and is often noticed during regular self-checks or when dressing.
• Nipple or breast pain: Discomfort that feels sharp, aching, or persistent, affecting one area of the breast or the nipple. This pain is not usually linked to the menstrual cycle and may worsen over time.
• Skin dimpling or puckering: The skin on the breast may start to pull inward or appear wrinkled in a localised area. This can occur when a tumour pulls on the tissue beneath the skin and may give the skin an uneven or dimpled texture.
• Redness or warmth of the breast: Inflammation of the breast skin, often with visible redness, increased temperature, or swelling. These may suggest an infection or an aggressive form of cancer like inflammatory breast cancer.
• Nipple inversion or flattening: The nipple may start to point inward or lie flat against the breast surface. A sudden change in nipple appearance should be checked, especially if only one side is affected.
• Nipple discharge: Fluid leaking from the nipple without squeezing or stimulation. It may be clear, milky, yellow, or bloody. Any discharge that appears spontaneously, especially from one nipple, needs medical evaluation.
• Skin changes on the breast or nipple: Flaking, peeling, thickening, or scaling of the skin around the nipple or elsewhere on the breast. These may resemble eczema but should not be ignored if they persist.
• Swelling of part or all of the breast: The breast may appear visibly enlarged, feel heavy, or become firm. This can occur with or without a distinct lump and may be accompanied by tight or stretched skin.
• Swollen lymph nodes near the collarbone or armpit: Small, firm lumps in these areas may be the first sign that cancer has spread beyond the breast. These nodes may not be painful but can be felt during a physical examination or self-check.

Any new, unexplained change in the breast or nipple should prompt a visit to a healthcare provider, even if there is no pain. 

How is Breast Cancer Diagnosed?

Breast cancer diagnosis involves a combination of physical examination, imaging tests, and tissue analysis.

Imaging Tests

If anything abnormal is found, imaging tests are done to examine the breast tissue more closely.

• Mammography is usually the first test. It uses low-dose X-rays to identify suspicious areas, even before symptoms develop.
• Ultrasound helps distinguish between solid lumps and fluid-filled cysts and is often used alongside a mammogram.
• MRI (Magnetic Resonance Imaging) provides a more detailed view, especially for people with dense breast tissue or a higher risk of breast cancer. It may also be used when other test results are unclear.

Biopsy

If imaging shows an area of concern, a biopsy is needed to confirm whether cancer is present. During this procedure, a small sample of breast tissue is taken and examined under a microscope.

Types of biopsy include:

• Fine-needle aspiration: uses a thin needle to collect fluid or cells.
• Core needle biopsy: removes a small cylinder of tissue.
• Surgical biopsy: used when a larger or more complex tissue sample is needed.

Hormone Receptor and HER2 Testing

If cancer is detected, further testing is done on the tissue sample to check for hormone receptors (oestrogen and progesterone) and HER2 protein levels. These results help determine the type of breast cancer and guide treatment choices.

Lymph Node Assessment

To check if the cancer has spread beyond the breast, nearby lymph nodes, especially in the underarm, may be evaluated. This may involve imaging or a needle biopsy, depending on the situation.

What are the Stages of Breast Cancer?

Breast cancer staging is based on the tumour size, lymph node involvement, and whether the cancer has spread to other parts of the body. Doctors use these stages to plan treatment and understand how far the cancer has progressed.

Stage 0 (Carcinoma in Situ)

This is a very early form of breast cancer where abnormal cells are found but have not spread beyond the ducts or lobules into the surrounding breast tissue. It is non-invasive and usually has a good outlook with proper treatment.

Stage I

The cancer is invasive, meaning it has spread into surrounding breast tissue, but remains small in size. It may have reached a very small number of nearby lymph nodes or none at all. At this stage, the disease is usually still treatable with surgery and possibly additional therapy.

Stage II

The tumour is either larger or has spread to nearby lymph nodes. The cancer may still be within the breast or in a small number of lymph nodes under the arm. Although more advanced than stage I, many cases are still highly treatable with a combination of surgery, chemotherapy, radiation, or hormone therapy.

Stage III

This stage is often referred to as locally advanced breast cancer. The tumour may be quite large and may have grown into the chest wall or skin. It usually involves more lymph nodes, including those under the arm and around the collarbone. Treatment is typically more intensive and may involve a mix of chemotherapy, surgery, and radiation.

Stage IV

Also known as metastatic breast cancer, this stage means the cancer has spread beyond the breast and nearby lymph nodes to other parts of the body such as the bones, liver, lungs, or brain. It is considered incurable but can often be managed with ongoing treatment to control symptoms and slow progression.

What Treatment Options are Available for Breast Cancer?

Breast cancer is treated using one or more types of therapies depending on the type of cancer, how far it has spread, and the person's overall health. Treatment is usually planned after considering hormone receptor status, HER2 status, tumour size, and lymph node involvement. Here are the main treatment options:

Surgery

Surgery is often the first step in treating breast cancer. The aim is to remove the tumour and, if needed, nearby tissues. Two common types include:

• Lumpectomy: The tumour and a small amount of surrounding healthy tissue are removed. This is usually followed by radiotherapy.
• Mastectomy: The entire breast is removed. Some patients also need removal of nearby lymph nodes to check if the cancer has spread.
  In some cases, breast reconstruction may be done immediately after mastectomy or at a later stage.

Radiotherapy

Radiation uses high-energy X-rays to destroy any cancer cells that may remain after surgery. It’s usually given after a lumpectomy and sometimes after a mastectomy, especially if there’s a high risk of recurrence. Radiation is directed at the breast, chest wall, or lymph node areas, and typically lasts a few weeks.

Chemotherapy

Chemotherapy involves strong anti-cancer medicines that travel through the bloodstream. It may be given:

• Before surgery (neoadjuvant) to shrink the tumour and allow breast-conserving surgery.
• After surgery (adjuvant) to kill any remaining cancer cells and reduce the risk of recurrence. It is also used for advanced or metastatic breast cancer. Chemotherapy can have side effects like hair loss, tiredness, and an increased risk of infection.

Hormone Therapy (Endocrine Therapy)

Used for hormone receptor-positive cancers, this therapy blocks the effect of oestrogen or reduces its levels in the body, slowing the growth of hormone-sensitive tumours. Common forms include:

• Medicines that block oestrogen receptors
• Medicines that stop the body from making oestrogen (in postmenopausal individuals)

Hormone therapy is usually taken for five years or more after initial treatment.

Targeted Therapy

This treatment is aimed at specific proteins or genes that help cancer cells grow. One of the most common targets in breast cancer is HER2, a protein found in some aggressive cancers. Targeted therapy drugs work by attaching to HER2 receptors and blocking cancer cell growth. These therapies are often combined with chemotherapy.

Immunotherapy

This treatment helps the immune system detect and destroy cancer cells. It is currently used in certain cases, such as triple-negative breast cancer that expresses specific markers. Immunotherapy may be combined with chemotherapy to improve its effectiveness.

Can Breast Cancer be Prevented?

There is no sure way to prevent breast cancer, but certain habits and measures may help reduce the risk:

• Maintain a healthy weight: Being overweight, especially after menopause, increases breast cancer risk. A balanced diet and regular activity can help maintain a healthy body weight.
• Stay physically active: Engaging in moderate exercise for at least 30 minutes on most days may lower hormone levels linked to breast cancer and support overall health.
• Limit alcohol intake: Alcohol can increase oestrogen levels. Limiting intake to no more than one drink per day, or avoiding it, may reduce the risk.
• Avoid smoking: Tobacco use has been linked to many cancers, including breast cancer, especially in younger women.
• Breastfeed, if possible: Women who breastfeed for several months may have a slightly lower risk of breast cancer, possibly due to hormonal changes during breastfeeding.
• Limit hormone therapy after menopause: Combined hormone therapy over long periods raises breast cancer risk. If needed, it should be used at the lowest dose for the shortest time under medical advice.
• Be aware of family history: A strong family history or inherited gene mutations (like BRCA1 or BRCA2) can significantly raise risk. Genetic counselling and testing may be recommended.
• Consider risk-reducing measures if high-risk: Those at high genetic risk may benefit from medications (such as hormone-blocking drugs) or preventive surgeries. These options should be discussed thoroughly with a specialist.
• Go for regular screening tests: Routine mammograms and clinical breast exams can help detect changes early, when treatment is more likely to be successful.
• Watch for any changes in your breasts: Being familiar with how your breasts normally look and feel makes it easier to notice changes like lumps, skin changes, or nipple discharge. Report these to a doctor promptly.

Consult Today

Facing the possibility of breast cancer can be overwhelming, but timely care from the right medical team can make a real difference. At Max Hospital, patients have access to dedicated oncologists and breast cancer specialists who are experienced in handling complex cases with attention to both physical and emotional wellbeing. If you or a loved one has noticed any symptoms or needs further evaluation, it’s best to book an appointment with us as soon as possible.