Carcinoma is a type of cancer that starts in cells that make up the skin or the tissue lining organs, such as the liver or kidneys.
Like other types of cancer, carcinomas are abnormal cells that divide without control. They are able to spread to other parts of the body, but don't always. "Carcinoma in situ" stays in the cells where it started.
Not all cancers are carcinoma. Other types of cancer that aren't carcinomas invade the body in different ways. Those cancers begin in other types of tissue, such as:
Types of Carcinoma
Although carcinomas can occur in many parts of the body, you may often hear people talk about these common types of carcinoma:
- Basal cell carcinoma
- Squamous cell carcinoma
- Renal cell carcinoma
- Ductal carcinoma in situ (DCIS)
- Invasive ductal carcinoma
Basal cell carcinoma. This is the most common form of all cancers. It occurs in cells lining the deepest part of the skin's outer layer.
You should get quick treatment for basal cell carcinoma to avoid scars. But only in very rare cases does this type of carcinoma spread to other parts of the body.
Basal cell carcinomas often look like:
- Open sores
- Red patches
- Pink growths
- Shiny bumps or scars
If you have basal cell carcinoma it's likely that you got it because of too much time in the sun. You may have had a few bad sunburns or else spent a lot of time in the sun during your life.
Squamous cell carcinoma. Most people think of skin cancer when they hear the words "squamous cell carcinoma." And it is true that this type of carcinoma often shows up on the skin.
But squamous cell carcinoma can also be found in other parts of the body, such as cells lining:
- Certain organs
- Digestive tract
- Respiratory tract
When squamous cell carcinoma develops in the skin, you often find it on areas that are exposed to the sun, such as the:
- Backs of the hands
Squamous cell carcinoma that develops on the skin is usually caused by spending too much time in the sun over the course of your life. This type of skin cancer tends to grow and spread more than basal cell cancers. In rare cases, it may spread to the lymph nodes.
Squamous cell carcinomas may crust or bleed and can include:
- Scaly red patches
- Open sores
- Growth with a depression in the middle
Renal cell carcinoma. This is the most common type of kidney cancer. It usually grows as a single tumor within the kidney.
Renal cell carcinoma is sometimes discovered when you have a CT scan or an ultrasound for another reason. Sometimes it is detected after it has already become very large or spread to other organs.
Ductal carcinoma in situ (DCIS). This is a condition where cancer cells are found inside the ducts of the breast.But in DCIS, the cancer has not fully developed or spread into nearby areas. Nearly all women diagnosed with this can be cured.
Invasive ductal carcinoma. This type of breast cancer starts in a milk duct but spreads into the fatty tissue of the breast. It can spread to other parts of the body through the lymph system and bloodstream.
It may be discovered as a suspicious mass through a mammogram by your health provider or during a breast self-exam.
Other symptoms may include:
- Thickening of the breast skin
- Rash or redness of the breast
- Swelling in one breast
- New pain in one breast
- Dimpling around the nipple or on breast skin
- Nipple pain, nipple turning inward, or nipple discharge
- Lumps in underarm area
Adenocarcinoma. This is a type of carcinoma that starts in cells called "glandular cells." These cells make mucus and other fluids. The glandular cells are found in different organs in your body.
Adenocarcinomas can occur in different parts of the body. Some examples of cancers that can be adenocarcinomas include lung, pancreatic, and colorectal types.