Breast Cancer Diagnosis

Diagnosing breast cancer accurately and early is crucial for effective treatment and better outcomes. The process involves several steps, each designed to assess symptoms, evaluate risks, and confirm the presence of cancer cells.


How Is Breast Cancer Diagnosed?

Diagnosing breast cancer involves a series of steps designed to detect the disease early and accurately. Each diagnostic tool contributes crucial information that helps healthcare providers offer the best treatment. Understanding this process can alleviate some of the anxiety associated with breast cancer diagnosis and prepare patients and their families for the journey ahead.


Initial Evaluation

The diagnostic process often begins when a person notices symptoms (like a lump in the breast or changes in breast shape or texture) or during a routine screening. The most common first steps include:

  • Self-examination and Clinical Breast Exam (CBE): During self-examination, individuals may discover lumps or abnormalities, prompting a visit to a doctor.
  • Medical History Review: The doctor will discuss the patient's personal and family medical history, focusing on any risk factors for breast cancer.


What is a Clinical Breast Examination?

A CBE is a physical exam performed by a doctor trained to recognise various breast conditions. It plays a role in identifying breast abnormalities that may require further investigation. During a CBE, the doctor:

  • Inspects the Breasts: The patient will be asked to sit or stand with her arms in different positions, such as above her head and on her hips. The provider looks for changes in breast shape, skin texture, and any signs of dimpling or puckering.
  • Palpates the Breasts: Using the pads of the fingers, the doctor examines the entire breast, underarm, and collarbone area for lumps or abnormalities. The examination is done systematically, covering all areas of the breast. Both the left and right breasts are examined for comparison.
  • Assesses Nipple Discharge: If there is any discharge from the nipples, the doctor may collect a sample for analysis.


CBE is recommended every three years for women in their 20s and 30s and annually for women 40 and older as part of a regular health exam.


Imaging Tests

If initial examinations suggest abnormalities, imaging tests are used to visualise the inside of the breasts:

  • Mammography: The most common screening test for breast cancer, mammography uses low-energy X-rays to examine breast tissue. It can detect tumours that cannot be felt and find microcalcifications (tiny deposits of calcium) that sometimes indicate the presence of breast cancer.
  • Ultrasound: This test uses sound waves to produce images of structures inside the body. It can help determine if a breast lump is solid (potentially cancerous) or fluid-filled (like a cyst, usually benign).
  • Magnetic Resonance Imaging (MRI): MRI of the breast is used in certain cases, especially for those with high risk of breast cancer or dense breast tissues, to provide a more detailed image.


Biopsy

A biopsy is the only definitive way to diagnose breast cancer. During a biopsy, a doctor removes a small amount of tissue from the suspicious area, which a pathologist examines under a microscope. There are several types of biopsies:

  • Fine-needle aspiration (FNA) biopsy: Involves using a thin needle to remove a small sample of cells.
  • Core needle biopsy: Uses a larger needle to remove a core of tissue.
  • Surgical biopsy: Either part (incisional biopsy) or all (excisional biopsy) of a lump or suspicious area is removed and tested.


Fine Needle Aspiration (FNA)

FNA is a type of biopsy procedure used to diagnose breast lumps or abnormalities. A thin needle is inserted into the lump or suspicious area to withdraw cells or fluid. This can be performed with palpation or imaging techniques like ultrasound.


FNA is less invasive than other biopsies. It does not usually require stitches or leave a scar. It is quicker and has fewer complications. However, FNA may not obtain enough tissue for an accurate diagnosis, leading to a need for a follow-up biopsy.


Pathological Testing

After a biopsy, the extracted tissue undergoes a detailed examination. Pathologists look for cancer cells and, if present, determine the grade and type of cancer. Additional tests on the cancer cells, such as hormone receptor tests and HER2/neu tests, can help guide treatment options.


Breast Cancer Grade

Cancer cells are graded according to how different they are from normal breast cells and how quickly they grow. 

Grade 1 - Low Grade

Cancer cells look a little different from normal cells. They are usually slow-growing.


Grade 2 - Intermediate Grade

Cancer cells do not look like normal cells. They are growing faster than grade 1 cancer cells.


Grade 3 - High Grade

Cancer cells look very different from normal cells. They are fast growing. 


Breast Cancer Types

Histological Subtypes

Breast cancer can be classified according to histological subtypes based on how the cancer cells look under the microscope.


Invasive ductal carcinoma (IDC) accounts for 80% of breast cancers. Cancer cells form in the breast ducts and spread into the surrounding breast tissue. IDC tend to grow together in a mass, making them easier to find. 


Invasive lobular carcinoma (ILC) accounts for 10% of breast cancers. Cancer cells form in the breast lobules and spread into the surrounding breast tissue. ILC tends to grow in more than one breast area in a sheet-like pattern, making them more difficult to detect.


Other rare histological subtypes include tubular, cribriform, mucinous, medullary, papillary, micropapillary, apocrine and metaplastic carcinomas. 


Molecular Subtypes

Breast cancer can also be classified into molecular subtypes, depending on the presence of certain receptors on the cancer cells. Receptors are molecules that cancer cells produce on their surface, which can interact with specific proteins and hormones in the body that allow the cancer to grow and spread.   


Hormone receptor positive breast cancer (70-80%) has cells with receptors for female hormones oestrogen and/or progesterone, which stimulates the cells to grow. These cancers respond to endocrine treatment that limits the body’s production of oestrogen and progesterone or stops the receptors from recognising the hormones. 


HER2-positive breast cancer (15-20%) has cells with much higher levels of HER2 receptors than normal. HER2 is a protein that promotes cell growth and is found on the surface of all breast cells. About 50% of HER2-positive breast cancers are also hormone receptor-positive. Targeted therapy and chemotherapy are usually recommended for these cancers. 


Triple-negative breast cancer (10-20%) does not have hormone or HER2 receptors. These cancers do not respond to endocrine therapy or targeted therapy aimed at HER2 but generally respond to chemotherapy. 


Special Types

Special or unusual traits group some breast cancers.


Paget’s disease of the nipple is an uncommon type of breast cancer in which cancer cells grow in the nipple-areolar complex. This causes the nipple skin to become red, painful, scaly and sometimes ulcerated, and it may be associated with blood-stained or clear nipple discharge. Many people with Paget’s disease also have either in situ or invasive carcinoma somewhere else in the breast. Treatment for Paget's disease is similar to treatment for other types of breast cancer, except surgery (either lumpectomy or mastectomy) requires removal of the nipple-areolar complex.


Inflammatory breast cancer is a rare and aggressive form of breast cancer in which cancer cells block the lymph vessels in the breast. This causes the breast to become swollen, red and tender. Inflammatory breast cancer is often triple-negative or HER2-positive. Treatment for inflammatory breast disease involves a combination of chemotherapy, surgery and radiotherapy. Surgery usually consists of a mastectomy and axillary dissection. 


Staging

Once breast cancer is diagnosed, staging tests are performed to determine the extent of the disease. 


Tests to Stage Breast Cancer 

CT Scan 

A CT scan uses x-ray beams to create detailed, cross-sectional pictures of the inside of your body. You will have a CT scan of your brain, chest, abdomen and pelvis. To prepare for a CT scan, you will be asked not to eat for some time. Before a CT scan, you may have an injection of dye and/or be asked to drink a liquid dye. The dye, known as contrast, helps ensure that anything unusual can be seen more clearly. You must then lie still on a table while the scanner takes pictures. The scan itself will take around 15 minutes. 


Bone Scan 

A bone scan may be done to see if the breast cancer has spread to your bones. Before the scan, you will be injected with a small amount of radioactive material. This material is attracted to areas of bone where there is cancer. You will be asked to return 2 to 3 hours later and then be scanned. 


PET-CT Scan 

A PET scan combined with a CT scan provides more detailed and accurate information than a CT scan. To prepare for a PET–CT scan, you will be asked not to eat or drink for some time. Before the scan, you will be injected with a glucose solution containing a small amount of radioactive material. Some cancer cells may appear brighter on the scan because they take up more glucose solution than normal cells. You will be asked to sit quietly for 30 to 90 minutes as the glucose spreads through your body, and then you will be scanned. The scan itself will take around 30 to 60 minutes.


The stage of cancer, which ranges from 0 to IV, is critical for choosing the best treatment approach. It describes the size of the cancer and how far it has spread. Stage I and II are referred to as early breast cancer. Stage III is referred to as locally advanced breast cancer. Stage IV breast cancer means it has spread to other parts of the body and is referred to as advanced or metastatic breast cancer.


Multidisciplinary Team Review

The results from all tests are typically reviewed by a multidisciplinary team that includes oncologists, radiologists, pathologists, and surgeons. This team collaborates to form a comprehensive treatment plan based on the diagnosis and staging results.


Genetic Testing

For some individuals, especially those with a family history of breast cancer or other cancers, genetic testing for mutations in genes like BRCA1 and BRCA2 may be recommended. The results can influence treatment choices and preventive measures.

Understanding these components of breast cancer diagnosis helps in managing the detection and treatment process effectively, providing critical support for patients navigating their medical care.

Share by: