There are more than 100 types of cancer, but most can be classified under one of four major categories: carcinoma, leukemia, sarcoma or lymphoma.
Carcinoma is a type of cancer that arises in the lining of cells, such as the skin or the lining of a digestive organ. According to the American Cancer Society, "at least 80 percent of all cancers are carcinomas."
Basal Cell Carcinoma
The most common type of cancer in the United States is basal cell carcinoma, a skin cancer that arises in the deepest layer of the epidermis (top skin layer).
Basal cell carcinoma is often the result of excessive sun exposure. Other possible risk factors include: contact with arsenic, radiation exposure, chronic inflammatory skin conditions, and complications of burns, scars, infections, vaccinations or tattoos.
There are many treatment options for carcinoma, including: radiation, cryosurgery, laser treatment and chemotherapy.
After treatment, basal cell carcinoma can return or new skin cancers can develop. Up to 50 percent of people treated for basal cell carcinoma will develop a new skin cancer within five years.