Invasive ductal carcinoma (IDC)

Invasive ductal carcinoma (IDC) is the most common type of breast cancer, accounting for approximately 80% of all breast cancer diagnoses. IDC starts in the milk ducts of the breast and spreads to surrounding breast tissues.

If you’re diagnosed with IDC, our cancer specialists at Advocate Cancer Institute are here for you. From genetic testing to access to clinical trials, we offer the most comprehensive cancer care in Illinois.

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Invasive ductal carcinoma risk factors

Multiple factors contribute to the risk of developing invasive ductal carcinoma, ranging from family history, genetic mutations and lifestyle factors. If you have a family history of breast cancer, genetic testing can help assess your risk, especially for gene mutations associated with increased risk of breast cancer.

Other risk factors include:

• Age: ;While IDC can occur at any age, women over 50 are more likely to develop it.
• Dense breast tissue: Women with dense breast tissue on mammograms face an increased risk of both IDC and invasive breast cancer.
• Hormonal factors: Factors that affect hormone levels, like early menstruation, late menopause, childbirth after 30 and prolonged use of hormone replacement therapy may escalate IDC risk.
• Lifestyle factors: Obesity, excessive alcohol consumption and a lack of exercise can also contribute to a higher IDC risk.
• Personal history of breast cancer: A prior diagnosis of breast cancer in one breast increases your risk of developing IDC in the opposite breast.
• Radiation exposure: Past radiation therapy to the chest, especially during childhood or teenage years, increases the likelihood of IDC later in life.

Invasive ductal carcinoma symptoms

Invasive ductal carcinoma has varying symptoms, although you may not experience any symptoms at all – especially in the early stages.

Common signs and symptoms of IDC include:

• A breast lump
• Changes in the appearance of your breast
• Changes in your nipple
• Breast pain
• Enlargement of your lymph nodes

These symptoms can also be caused by conditions other than breast cancer, such as fibrocystic changes, infections or non-cancerous tumors. If you notice any persistent changes in your breast health or experience any of the symptoms mentioned above, schedule an appointment with your doctor.

Diagnosing invasive ductal carcinoma

If you suspect you have a type of breast cancer, you'll start with a physical exam by your doctor. Your medical history and symptoms will be discussed, and your doctor will perform a breast exam to check for lumps.

Imaging tests such as a mammogram, ultrasound or MRI may be performed to get more detailed images of the breast tissues and identify any suspicious areas.

If a suspicious area is identified on imaging tests or during a clinical examination, a biopsy may be performed to obtain a sample of tissue for further analysis. After a biopsy or the removal of a lump, the tissue that was removed may be tested for:

• Hormone receptors: A hormone receptor is a cell protein that binds to a hormone. The hormones estrogen and progesterone may help some cancer cells grow. If your breast cancer cells have too many hormone receptors for estrogen or progesterone, we can treat those cells with hormone therapy.
• HER-2 status (sometimes referred to as ErbB2): HER-2 is a gene that helps control how cells grow, divide and repair themselves. About one in four breast cancers have too many copies of the HER-2 gene. These cancers tend to grow quickly.

Once a diagnosis of IDC is confirmed, additional tests may be ordered to determine the extent of the cancer and whether it has spread to other parts of your body. Grading and staging your cancer play a crucial role in determining the severity and aggressiveness of breast cancer.

Stages of breast cancer

After a diagnosis, your care team will determine whether the cancer has spread and to what extent. This is known as staging, and it is crucial for knowing how severe the cancer is and developing the right treatment plans.

Breast cancer stages range from stage 0 (carcinoma in situ) to stage IV (metastatic cancer). The lower the stage, the less it has spread. The higher the stage, the more it has spread. Cancers in higher stages have lower survival rates.

What is a invasive ductal carcinoma grade?

Invasive ductal carcinoma is typically defined by its grade. The invasive ductal carcinoma grade provides valuable insights into the behavior and aggressiveness of breast cancer cells. Understanding the grade of your tumor allows your provider to tailor treatment plans to your specific needs and helps predict your prognosis.

The grading system helps predict how quickly cancer may grow and spread. Typically, invasive ductal carcinoma is graded on a scale of one to three, with one being the least aggressive and three being the most aggressive.

• Grade 1 (low grade): Cancer cells closely resemble normal breast tissue cells. They tend to grow and spread slowly, making this grade of IDC less aggressive.
• Grade 2 (intermediate grade): Cancer cells display some abnormal characteristics but are not as different from normal cells. They may grow and spread at a moderate rate.
• Grade 3 (high grade): Cancer cells appear significantly different from normal cells. They are more aggressive, tend to grow and spread rapidly, and have a poorer prognosis.

Understanding the grade of IDC is vital to help your doctor determine the best treatment possible and prognosis.

Treatment for invasive ductal carcinoma

Invasive ductal carcinoma treatment depends on several factors, including the stage and characteristics of your cancer, and your overall health and personal choices.

Treatment typically involves a combination of approaches aimed at removing or destroying the cancer cells and preventing cancer recurrence.

Your IDC treatment plan may include:

• Lumpectomy (breast conserving surgery): This procedure involves removing the cancerous tumor through surgery along with a margin of surrounding healthy tissue while preserving as much of the breast as possible. It’s often followed by radiation therapy to reduce the risk of cancer returning.
• Radiation therapy: Radiation therapy uses high-energy beams to target and destroy cancer cells. It’s often used to kill any remaining cancer cells in your breast or chest wall and reduce the risk of it returning.
• Mastectomy: In some cases, a mastectomy may be recommended, which involves removing the entire breast tissue. Depending on the extent of the cancer and your preferences, a mastectomy may be followed by breast reconstruction surgery.
• Chemotherapy: ;Chemotherapy involves the use of drugs to kill cancer cells or prevent them from growing and dividing. It may be recommended before or after surgery to shrink the tumor, reduce the risk of recurrence or treat cancer that has spread to other parts of the body.
• Hormone therapy: Hormone therapy is used to treat hormone receptor-positive breast cancers, which account for most invasive ductal carcinomas. It works by blocking the effects of estrogen or reducing estrogen levels in the body.
• Targeted therapy: Targeted therapy drugs specifically target certain molecules or pathways involved in cancer growth and progression.

Your care team at Advocate Health Care will use a collaborative approach to provide the best treatment possible. Additionally, supportive care services such as counseling, nutrition therapy, palliative care and physical therapy may be offered to help you manage the physical and emotional challenges of cancer treatment.

What is the prognosis for invasive ductal carcinoma?

The prognosis for invasive ductal carcinoma depends on several factors, including the stage of the cancer, the presence of estrogen and progesterone and the grade of the tumor. Generally, early-stage IDC with low-grade tumors has a better prognosis than late-stage IDC with high-grade tumors.

Which invasive breast cancer has the best prognosis?

Among the various types of invasive breast cancer, hormone receptor-positive tumors tend to have the best prognosis. These tumors are often responsive to hormone therapy and have a lower risk of recurrence compared to other types.