Breast cancer stages, treatment and treatment side effects

Breast cancer is the most common cancer in females in the UK but also has a high survival rate of 75% after 10 years. 

Diagnosing breast cancer in its early stages improves the chances of successful treatment. Consequently, breast cancer screening (mammogram) is offered to all females in the UK, every three years, between the ages of 50 and 71 years.

Types of breast cancer

There are three main types of breast cancer, which relate to where in the breast the cancer originates. 

The most common type of breast cancer is ductal carcinoma, which starts in the milk ducts of the breast — thin tubes that carry breast milk from the milk-producing lobules to the nipple. Ductal carcinoma can be limited to the ducts (ductal carcinoma in situ) or can spread beyond the ducts (invasive ductal carcinoma). 

The second most common type of breast cancer is lobular carcinoma, which starts in the breast lobules that represent the glandular part of the breast. 

The third type of breast cancer has a mixture of features seen in ductal and lobular carcinoma. 

Whichever type of breast cancer you have, your treatment will involve both medical and surgical interventions, as well as psychological and emotional support. This is because living with breast cancer and coping with treatment can significantly affect your mental health and have an impact on your friendships, family, work and leisure time. 

To ensure you receive all the support and care you need, you will have a multidisciplinary care team, including your GP, a surgeon, an oncologist and a specialist cancer nurse. 

Breast cancer stages and treatment

The progression of breast cancer is divided into four stages.

Stage one

The cancer is small (up to 2 cm) and limited to the breast tissue (ie no spread to the armpit lymph nodes). Surgery to remove the cancer may be enough to treat stage one breast cancer. However, radiotherapy and, sometimes hormone-blocking tablets are also needed. For example, tamoxifen is used to treat oestrogen-responsive breast cancer, which accounts for three-quarters of all cases of breast cancer. 

Chemotherapy is not commonly needed at this stage and is usually only recommended if stage one breast cancer has a specific profile of proteins ie triple-negative or HER2-positive types, which tend to be more aggressive and progress faster. HER2-positive breast cancer accounts for around one in five cases of breast cancer.  

Stage two

The cancer can be slightly larger in the breast tissue and/or may spread to a limited number (1–3) of armpit lymph nodes. This may still be considered an early-stage breast cancer and can be treated very similarly to stage one breast cancer except that surgery to remove the armpit lymph nodes may sometimes be needed and chemotherapy and radiotherapy are more frequently needed, particularly in younger women.

Stage three

The cancer has spread from the breast to the lymph nodes close to the breast, the skin covering your breast or the muscles underlying your chest wall. The cancer in this stage is sometimes called locally advanced cancer.

Treatment may include upfront chemotherapy and additionally or alternatively, targeted cancer drugs or hormone-blocking tablets. This is in order to shrink the cancer before removal. After surgery, you will usually need radiotherapy or further treatment with chemotherapy and/or targeted cancer drugs or hormone-blocking medications. This approach reduces the risk of the cancer returning in the future and significantly improves survival rates.

Stage four

At stage four, the cancer has spread from the breast to other parts of your body (eg your bones, liver and/or lungs). This is advanced breast cancer and is rarely treatable. Instead, treatment uses chemotherapy and/or hormone-blocking drugs to control the growth of your cancer and prolong your life. Treatment aims to strike a balance between your comfort and quality of life and the need to limit the growth of your cancer.

Complications and side effects of breast cancer treatment

Surgery

Every surgery comes with risks, including bleeding, tissue damage, blood clots and infection. Steps are always taken to reduce these risks as much as possible.

For example, the risk of infection is reduced by giving intravenous antibiotics immediately before starting surgery and sometimes for varying periods of time after surgery; Eg if you’re having a breast reconstruction at the same time, you may need a longer course of antibiotics post-surgery. 

The risk of bleeding is reduced by very carefully cutting through the breast tissue as the surgery progresses and immediately dealing with any bleeding when it occurs using cautery or stitches to seal off bleeding blood vessels. 

Chemotherapy

Chemotherapy produces a wide range of side effects, with one of the most widely known being hair loss. This is temporary and after completing your chemotherapy, your hair will grow back, initially slowly but after a few weeks from stopping chemotherapy, the regrowth will occur at a normal pace. You can request an ice (or cold) cap to wear on your head to help reduce hair loss — this works by contracting the tiny blood vessels that supply your hair follicles, reducing the toxic effects of the chemotherapy on them.

Other common side effects of chemotherapy include nausea and vomiting, diarrhoea and fatigue. The intensity of these side effects varies between individuals. 

Radiotherapy

Thanks to advances in radiotherapy technology, the side effects of radiotherapy are mainly localised to the area treated and not systemic (ie affecting the deeper organs). This is because the depth to which radiotherapy penetrates the body can be better controlled to, for example, reduce exposure of the heart and lungs to radiation.

Radiotherapy commonly causes redness and soreness of the skin, which settles down after radiotherapy is completed. However, in the long-term, radiotherapy can cause permanent hyperpigmentation ie darkening of the area of skin where treatment was applied (eg breast skin or mastectomy skin). This is more likely in darker-skinned individuals.

If you have had breast construction surgery, where an implant has been used, subsequent radiotherapy can cause capsular contraction. This refers to the formation of a layer of tissue around the implant (capsule) that can become thickened and deformed. In mild cases, no treatment is needed but in moderate to severe cases, the breast will visibly change shape as the capsule shrinks and surgery is needed to resolve this.