Less Common Breast Cancers - Types Of Breast Cancer: Breast Cancer

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Less common breast cancers

There are several less common forms of breast cancer that can be diagnosed by the pathologist. In general, the clinical manifestations (e.g., lump in the breast, suspicious finding on a mammogram or breast ultrasound) are indistinguishable (except for the illustration of inflammatory cancer) from the more common forms of infiltrating ductal cancer discussed earlier.

In general, breast cancers are characterized by whether they are so called "in situ" cancers or invasive cancers. The former type is confined to the breast ducts or lobules and has not yet invaded into the underlying breast tissue. A common form of in situ cancer, described earlier, is ductal carcinoma in situ (or DCIS), often identified by microcalcifications seen on mammography. In contrast, invasive cancers have invaded into the underlying breast tissue, traversing the ducts or lobules. Invasive cancers pose more significant medical issues.

The following are types of invasive carcinomas:

Medullary carcinoma

This invasive cancer may appear with a pink color to the pathologist and surgeon and has a relatively well-defined, distinct boundary between tumor and normal breast tissue. About 5% of all breast cancers are of this type, and its prognosis is better than for invasive lobular or invasive ductal carcinomas. It can exhibit different degrees of aggressiveness.

Tubular carcinoma

This accounts for 2% of breast cancers, and its cells look like little tubes (hence the name). It is an invasive cancer, but it spreads beyond the breast only infrequently, and therefore has a better prognosis than invasive ductal or lobular carcinomas.

Colloid or mucinous carcinoma

Also rare, this is an infiltrating ductal cancer that is formed by mucus-producing cancer cells.

Papillary carcinoma

Extremely rare, the cells of this particular breast cancer stick out like little papules, or finger-like projections. This form of cancer can be either invasive or in situ.

Inflammatory breast cancer

Symptoms of this advanced form of breast cancer are breast swelling and skin that looks red and feels warm. The redness occurs because cancer cells in the skin's lymphatic channels block fluid drainage from the lymph vessels of the skin. Frequently there is not a distinct lump, and the first impression is that of infection. The other characteristic that on occasion may accompany inflammatory breast cancer is a peculiar skin appearance that resembles the outside skin of an orange, so called peau d'orange. This finding represents swelling and redness of the skin, and usually has an abrupt onset. Infections either improve or worsen, so if you have breast inflammation that doesn't clear up after one to two weeks of antibiotics, you should see a breast surgeon, who will probably order a mammogram and then perform a biopsy of the skin. This is an unusual type of breast cancer, and it's an aggressive one.

Last updated:	April 23, 2007