Invasive ductal carcinoma
Invasive ductal carcinoma (IDC) begins in the milk ducts and spreads to the fatty tissue of the breast outside the duct. IDC accounts for about 80 percent of invasive breast cancers.
Invasive ductal carcinoma treatment options
Surgery typically is the first treatment for invasive ductal breast cancer. The goal of this treatment is to remove the cancer from the breast with a lumpectomy or mastectomy. The type of surgery recommended will depend on factors such as the location of the tumor, the size of the cancer and whether more than one area in the breast has been affected. For patients with ductal carcinoma, long-term systemic treatment with tamoxifen is recommended to prevent recurrence.
Four types of invasive ductal carcinoma are less common:
Medullary ductal carcinoma:
This type of cancer is rare and accounts for only 3 to 5 percent of breast cancers. It is called “medullary” because under a microscope, it resembles part of the brain called the medulla. Medullary carcinoma may occur at any age, but it typically affects women in their late 40s and early 50s. Medullary carcinoma is more common in women who have a BRCA1 gene mutation. Medullary tumors are often “triple-negative,” which means they test negative for estrogen and progesterone receptors and for the HER2 protein. Medullary tumors are less likely to involve the lymph nodes, are more responsive to treatment, and may have a better prognosis than more common types of invasive ductal cancer.
Mucinous ductal carcinoma:
This type of breast cancer accounts for less than 2 percent of breast cancers. Microscopic evaluations reveal that these cancer cells are surrounded by mucus. Like other types of invasive ductal cancer, mucinous ductal carcinoma begins in the milk duct of the breast before spreading to the tissues around the duct. Sometimes called colloid carcinoma, this cancer tends to affect women after they have gone through menopause. Mucinous cells are typically positive for estrogen and/or progesterone receptors and negative for the HER2 receptor.
Mucinous ductal carcinoma treatment options: Surgery is typically recommended to treat mucinous ductal carcinoma. A lumpectomy or mastectomy may be performed, depending on the size and location of the tumor. Adjuvant therapy, such as radiation therapy, hormonal therapy and chemotherapy, may also be required. Most mucinous carcinomas test negative for receptors for the protein HER2, so they are not typically treated with trastuzumab (Herceptin®).
Papillary ductal carcinoma:
This cancer is rare, accounting for less than 1 percent of invasive breast cancers. In most cases, these types of tumors are diagnosed in older, postmenopausal women. Under a microscope, these cells resemble tiny fingers or papules. Papillary breast cancers are typically small, and test positive for the estrogen and/or progesterone receptors and negative for the HER2 receptor. Most papillary carcinomas are invasive and are treated like invasive ductal carcinoma.
Papillary carcinoma treatment options: Surgery is typically the first-line treatment for papillary breast cancer. A lumpectomy or mastectomy may be performed, depending on the size and location of the tumor. After surgery, adjuvant therapy may be required and may include radiation, chemotherapy and/or hormone therapy.
Tubular ductal carcinoma:
Another rare type of IDC, this cancer makes up less than 2 percent of breast cancer diagnoses. Like other types of invasive ductal cancer, tubular breast cancer originates in the milk duct, then spreads to tissues around the duct. Tubular ductal carcinoma cells form tube-shaped structures. Tubular ductal carcinoma is more common in women older than 50. Tubular breast cancers typically test positive for the estrogen and/or progesterone receptors and negative for the HER2 receptor.
Tubular ductal carcinoma treatment options: Treatment options for tubular ductal carcinoma depend on the aggressiveness of the cancer and its stage. Treatment often consists of surgery, which includes a lumpectomy or mastectomy, and additional (adjuvant) therapy, which may include chemotherapy, radiation and/or hormone therapy.