What type of Breast Cancer do I have?
Most breast cancers arise from the cells that line the small tubes (or ducts) that connect to the glands that produce milk to the nipple. The two main types are invasive ductal carcinoma and non-invasive ductal carcinoma, also commonly called ductal carcinoma in situ. If the cancer is invasive, it means that the cancer cells have spread beyond the lining of the tube and there is a possibility that some cancer cells have spread through the lymph system or blood stream to other parts of the body. Non-invasive cancer stays in the tube and should not have spread to other areas.
What stage is my breast cancer?
The stage of breast cancer is determined by three things: the size of the tumor, the spread of the cancer to lymph nodes under the arm, and the spread to other parts of the body. This is the Classification of Malignant Tumors (TNM system) which are standards used to describe and categorize stages and progression of most types of cancer. A biopsy will not reveal the stage of the cancer. We can sometimes estimate the size of the tumor based or your mammogram, ultrasound, and exam but we don’t know the true size until it is completely removed. The lymph nodes under the arm (axillary nodes) are sampled at the time the tumor is removed. Spread to other parts of the body (metastasis) is usually microscopic and can’t be detected. In most patients, we routinely draw blood and perform a chest x-ray prior to surgery. If your tumor is large or you have symptoms that may be due to spread of the tumor to other parts of the body, we usually conduct a more sensitive test such as a CT or PET scan.
What types of surgery are recommended?
The two most common surgeries that breast cancer patients have are lumpectomy and mastectomy. Lumpectomy is when the surgeon removes the tumor and an area of normal breast tissue surrounding the tumor. After the tumor is removed, the edges, also called margins, are checked under a microscope to make sure the cancer does not extend outside the edge of the lumpectomy. When the tumor does extend into the edge this is called a “positive margin”, and there could still be cancer in the breast. The margins cannot be accurately determined at the time of surgery. It takes 2-3 days to receive the results of the microscopic study of the tissue from the pathologist. If the margins show that cancer is still present, a second operation is needed to remove more tissue around the original lumpectomy site. This occurs in 10-15% of cases. Lumpectomy is almost always followed by radiation treatment to the breast to help prevent a reoccurrence of cancer in the breast.
With a mastectomy, except for a small amount of tissue, the entire breast is removed. It is not possible to remove absolutely all of the breast tissue. A small amount of the tissue extends into the tissue beneath the skin that is spared to cover the chest wall. After a mastectomy, radiation is usually not needed unless the tumor is large or a certain number of lymph nodes contain cancer. Reconstruction of the breast can be done at the time of mastectomy or at a second surgery.
Is it better to have a lumpectomy followed by radiation or a mastectomy?
Several large studies have been done that divided breast cancer patients into two large groups. One group undergoing lumpectomy and radiation and the other group having a mastectomy. The long term outcome for each group was the same. This is because what causes death in breast cancer patients is the spread of the cancer (metastasis) to other parts of the body. If a patient has metastasis, it has occurred prior to diagnosis and the type of surgery performed does not change this.
A lumpectomy is less painful and typically better tolerated by most patients than a mastectomy. Patients go home the same day with a lumpectomy. Masectomy patients usually spend a night or two in the hospital after surgery. The cosmetic result after a lumpectomy is usually better than a mastectomy with reconstruction. The only disadvantage of a lumpectomy is that a lumpectomy surgery is followed by radiation treatment. As mentioned earlier, there is also about a 10-15% chance you may need a second surgery if the margins are positive.
A mastectomy has no advantage over a lumpectomy in terms of survival from breast cancer. Patients do not generally need radiation after a mastectomy and are less likely to require a second operation. A mastectomy can be a better choice if the patient has a large tumor or more than one tumor in the breast. Sometimes the tumor is too large to remove with a lumpectomy and a mastectomy is required. If a patient has a large tumor and would prefer a lumpectomy, sometimes, chemotherapy prior to surgery will shrink the tumor significantly. Then a lumpectomy may be considered instead of a mastectomy.
How are the lymph nodes sampled?
Breast cancer can spread to the axillary lymph nodes under the arm. It is important to sample these lymph nodes to help determine the stage of the cancer. Instead of removing a large group of lymph nodes like was done in the past, we now take a just a small sampling. This is called a sentinel lymph node biopsy. The lymphatic fluid from the breast drains into the axillary lymph nodes under the arm in a stepwise fashion. In other words, all the fluid drains through a first node then a second node then a third etcetera. If the first node in this chain does not contain breast cancer, there is about a 90% chance that the lymph nodes further in the chain do not contain breast cancer.