Ductal Carcinoma in Situ (DCIS) Treatment

Ductal Carcinoma in Situ is an abnormal growth of cells inside the milk ducts. It is considered a very early form of breast cancer and is referred to as non-invasive, pre-invasive, or stage 0 breast cancer. DCIS is one of the most treatable forms of breast cancer and can be treated with surgery or radiation therapy. However, if not diagnosed in time, it can spread to lymph nodes and then to other parts of the body, converting into invasive ductal carcinoma.

These mutations may result from a combination of genetic predisposition and environmental factors. Factors such as lifestyle, environment, and family history play a role in causing DNA mutations. However, no exact cause is not yet known, and research is still ongoing to find the reason behind these mutations. 

Several factors are associated with the development of DCIS. These include: 

• Family or personal breast cancer history: If there is a family or personal history of breast cancer, the risk of developing DCIS increases.
• Early menstruation or late menopause: Starting menstruation before the age of 12 or reaching menopause after the age of 55 increases the chances of developing breast cancer.
• Gender: Both males and females have breast tissue, but women are more prone to developing DCIS than men.
• Dense breast tissue: Dense breast tissue increases the chances of developing DCIS.
• Having children at an older age: Having children at an older age, particularly after 30 is associated with a higher risk of developing DCIS.
• Obesity: Being overweight also increases the risk of developing DCIS.
• Radiation therapy:  Receiving radiation to the chest area may elevate the risk of developing DCIS later in life.

DCIS does not usually cause any symptoms and is generally detected on a mammogram as tiny flecks of calcium in the breast tissue. These calcium deposits, known as microcalcifications, are often the first indicator of DCIS.

Some people may still experience the following symptoms:

• Lumps in the breasts
• Itchy skin in the breast area
• Nipple discharge (bloody)

DCIS diagnosis involves imaging tests and biopsy:

Mammogram

A mammogram provides higher-resolution images. It helps the doctor have a closer look at the calcium deposits in the breast tissue. These calcium deposits can sometimes turn cancerous.

Breast Ultrasound

Following a mammogram, a breast ultrasound may be ordered, which with the help of sound waves, provides clearer images of the breast tissue. Although not always required, an ultrasound can provide additional imaging information.

Biopsy

If any abnormalities are seen on imaging, the next procedure is generally a biopsy.

There are two types of biopsies: needle biopsy, in which a small tissue sample is taken using a needle, and surgical biopsy, where the sample is taken through a minor surgery. A pathologist then examines the cells under a microscope to determine if DCIS is present and, if so, what type it is.

DCIS is divided into three grades that directly reflect on the appearance and behaviour of the cancer cells:

Low Grade

The cancer cells in low-grade DCIS are slow-growing and only slightly different in appearance from normal cells. They are generally considered less dangerous and much less likely to become invasive carcinomas. Regular monitoring and treatment are still recommended to prevent progression. Low-grade DCIS may also show less abnormal cell activity seen in cancer.

Intermediate Grade

In this grade, the cancer cells grow at an average rate. Intermediate-grade DCIS has a moderate risk of invasion if left untreated; hence, prompt treatment is advised.

High Grade

High-grade DCIS cells look very different from normal cells and are more likely to divide and spread more rapidly than low-grade DCIS cells, making them a more serious type of cancer. Prompt intervention is essential to address the higher risk of progression to invasive cancer.

Surgery

Surgery is the primary treatment for DCIS and involves the removal of abnormal cells from the breast. There are two types of surgery for DCIS:

• Lumpectomy:Also known as breast-conserving surgery, this involves the excision of the DCIS along with an additional portion of surrounding healthy tissue to ensure the complete removal of abnormal cells. Radiotherapy may be subsequently administered after lumpectomy to reduce the chances of recurrence.
• Mastectomy: A mastectomy (removal of the entire breast) may be advised when DCIS is extensive or affects multiple breast regions. As DCIS is non-invasive, lymph node removal is typically not necessary during a mastectomy. Following a mastectomy, some patients may choose to have breast reconstruction, either during or after the procedure.

Radiation Therapy

Adjuvant radiation therapy is often prescribed after lumpectomy to destroy any remaining malignant cells in the breast tissue and lower the risk of DCIS recurrence. Radiation therapy is normally administered externally in small daily doses over several weeks. Modern advancements like intensity-modulated radiation therapy (IMRT) may help minimise side effects. Although radiation therapy reduces the risk of DCIS recurrence, it is not always required after mastectomy if the likelihood of its return is low.

Hormonal Therapy

Adjuvant systemic therapy may be recommended if the DCIS is hormone receptor-positive, meaning the cancer cells are stimulated by hormones like oestrogen. This therapy reduces the likelihood of DCIS recurrence and also lowers the risk of developing other types of breast cancer. Medications like tamoxifen or aromatase inhibitors are commonly prescribed for this purpose.

If left untreated, ductal carcinoma in situ can develop into invasive ductal cancer. It's critical to begin therapy as soon as possible after DCIS diagnosis.

People diagnosed with DCIS may be at higher risk of developing other health conditions, such as heart disease, high blood pressure, and osteoporosis. This is often due to shared risk factors or side effects of certain treatments like hormonal therapy.

Making modifications in everyday routine may help reduce the chance of ductal carcinoma in situ. These changes can include:

• Breast Self-Exam: By performing regular breast self-examinations, it may be possible to detect changes, lumps, or unusual symptoms. A breast exam cannot prevent breast cancer but it can aid in early detection if abnormalities are present. Although not a substitute for professional screenings, regular self-exams increase awareness of breast health.
• Regular Screening: Consult with a physician to determine the appropriate time to begin breast cancer screening. Enquire about the advantages and disadvantages of screening. Regular screening can help ensure that DCIS gets detected in time.
• Healthy Diet and Exercise: Maintain health and fitness by regular exercise and a balanced diet. Aim for at least 30 minutes of exercise on most days of the week. Consume a diet rich in fibre and protein, and low in sugars, saturated fats, and processed foods.
• Limit Hormone Therapy: Hormone therapy is often used to relieve menopausal symptoms. One of the downsides to hormone therapy is breast cancer risk. To lower the risk of breast cancer, use the shortest duration and lowest dose necessary. Always consult with a healthcare provider to weigh the benefits against potential risks.

Can altering one's lifestyle lower the chance of a DCIS recurrence following treatment?

A good diet, frequent exercise, reducing alcohol consumption, and quitting smoking can all improve breast health and lower the risk of DCIS recurrence. However, no lifestyle change can guarantee that it will not recur. Regular medical follow-ups remain essential for monitoring.

What effects does treatment for DCIS have on breast appearance, and are there options for reconstruction?

Breast appearance may be impacted by procedures like mastectomy or lumpectomy. Options such as nipple-sparing mastectomy and partial reconstruction can help improve aesthetic outcomes. For those undergoing a mastectomy, breast reconstruction can often be performed during the same procedure or later, depending on individual preferences and health considerations.

What is the healing period following DCIS surgery, and are there any particular guidelines for post-operative care?

The length of recovery varies based on personal health conditions and the type of surgery (mastectomy or lumpectomy). Many patients return to normal activities within a few weeks. Light activities like walking can often be resumed within a few days, but strenuous exercises should be avoided until cleared by the doctor. Following post-operative care instructions, such as proper wound care, activity restrictions, and attending follow-up appointments, is crucial for optimal recovery.

How is DCIS monitored following treatment to prevent progression and recurrence?

Physical examinations, routine mammograms, and, occasionally, imaging tests are all part of follow-up care. Lifestyle changes and adherence to prescribed medications, such as hormone therapy, may also be part of a comprehensive follow-up plan. The initial treatment approach, DCIS grade, and personal risk factors, all influence how frequently these follow-ups are conducted.

Is DCIS regarded as "real" cancer, and if it is non-invasive, why is treatment required? 

DCIS is classified as an early form of breast cancer. Treating DCIS early prevents the risk of invasive cancer, which can be harder to manage and pose greater health risks.

Reviewed By Dr. Sameer Khatri - Senior Director - Medical Oncology, Cancer Care / Oncology, Medical Oncology, Head & Neck Oncology, Gastrointestinal & Hepatobiliary Oncology on 19 Dec 2024.