Breast Cancer Explained: From Early Warning to Diagnosis

By Dr Jera (MD)

Disclaimer: Readers are strongly advised to consult a qualified and registered healthcare professional for any health concerns before making changes to their diet, lifestyle, or treatment.

Breast cancer can be frightening, particularly when medical terms such as DCIS and IDC appear on a report for the first time. Understanding what those terms mean can help patients ask better questions and make informed decisions with their healthcare teams.

PART 1: DCIS — Cancer Cells Still in Place

Ductal Carcinoma In Situ (DCIS) refers to abnormal cells found within the lining of the breast ducts. The cells have not broken through the duct wall into surrounding breast tissue. DCIS is therefore described as non-invasive breast cancer or Stage 0, although some medical authorities also describe it as a precancerous condition because some cases can progress to invasive cancer.

Importantly, doctors cannot currently predict with certainty which cases of DCIS will become invasive. DCIS usually causes no symptoms and is often detected through mammography, particularly as tiny calcium deposits known as calcifications. More than 90% of DCIS cases are diagnosed by mammography alone in some screening populations. It can sometimes be associated with a breast lump or nipple discharge, but many women will not feel anything unusual.

How is DCIS treated?

Treatment depends on factors such as the extent and grade of the DCIS, whether it is present in one or multiple areas, and the individual's circumstances. Treatment may include:

• Breast-conserving surgery (lumpectomy) to remove the abnormal area.

• Radiotherapy, which may be recommended after breast-conserving surgery.

• Mastectomy, particularly when the affected area is extensive or involves multiple areas of the breast.

• Hormone therapy, which may be considered when the DCIS is hormone-receptor positive.

The appropriate combination is determined by the treating team. The prognosis for DCIS is generally excellent. The National Cancer Institute reports that more than 98% of people diagnosed with DCIS are alive five years after diagnosis. However, a survival statistic is not a guarantee for an individual patient.

PART 2: IDC — When Cancer Becomes Invasive

Invasive Ductal Carcinoma (IDC) is the most common type of invasive breast cancer.

It begins in a milk duct but breaks through the duct wall and grows into the surrounding breast tissue. Once breast cancer becomes invasive, cancer cells can potentially enter lymphatic or blood vessels and spread to lymph nodes or other parts of the body. That is why identifying breast cancer before it becomes invasive can be important.

But breast cancer is not one disease with one outcome. The prognosis and treatment of invasive breast cancer depend on several factors, including the tumour's size and grade, lymph-node involvement, whether it has spread elsewhere, and biomarkers such as hormone-receptor and HER2 status.

PART 3: How Is Breast Cancer Diagnosed?

There is no single test that diagnoses every breast abnormality. Doctors may use a combination of clinical assessment, imaging and tissue sampling depending on what they find. This approach is sometimes described as the Triple Test:

1. Clinical assessment

A trained healthcare professional examines the breast and surrounding areas, looking for a lump or other changes.

2. Imaging

Imaging may include ultrasound, mammography or, in selected circumstances, MRI. The choice depends on factors including the patient's age, symptoms, clinical findings and individual risk. Mammography can detect some breast cancers before they produce symptoms and remains the standard screening test for most women for whom routine mammographic screening is recommended. A woman who has a breast symptom is not necessarily undergoing “screening”. She may instead require diagnostic imaging to investigate the specific abnormality.

3. Biopsy

If imaging or examination identifies a suspicious abnormality, a biopsy may be needed. A biopsy allows a pathologist to examine cells or tissue under a microscope. Different biopsy methods include: Fine-needle aspiration (FNA): A thin needle is used to remove fluid or cells. It can be useful in selected situations, including some cystic breast abnormalities.

Core-needle biopsy: A larger needle removes small cylinders of tissue for examination. It is commonly used to diagnose suspicious solid breast abnormalities and can be performed with imaging guidance.

Excisional biopsy: Surgery is used to remove an entire lump or abnormal area. It may be considered when a needle biopsy cannot establish the diagnosis or when there are other clinical reasons for surgical removal. A biopsy is the only definitive way to confirm breast cancer. Imaging alone cannot establish the diagnosis.

DCIS Is Not the Same as IDC

Think of the breast duct as a boundary. With DCIS, abnormal cells remain inside that boundary. With IDC, the cells have broken through it and entered surrounding breast tissue.

But the important message is not to live in fear of either term. The important message is to seek medical assessment when a breast change is persistent or concerning and to follow recommended screening appropriate to your age and risk.

A lump does not automatically mean cancer, and breast cancer does not always produce a lump. Mammography can detect some cancers before they become noticeable through symptoms.

Screening Is About Information, Not Fear

Breast cancer screening is intended to find cancer in people who do not yet have symptoms.

When breast cancer is found at an earlier stage, it may be easier to treat, and screening has been shown to reduce deaths from breast cancer. In Zimbabwe, breast cancer remains a major health concern. GLOBOCAN 2022 recorded 1,807 new breast cancer cases among women in Zimbabwe, making it the country's second most frequently diagnosed cancer among women after cervical cancer.

So do not ignore a persistent breast change.

Do not assume that the absence of pain means everything is fine.

And do not assume that every breast lump is cancer.

Ask questions. Get assessed. Follow the advice of a qualified healthcare professional.

Screening is not fear.

It is information, and information gives you choices.

breast cancer explained