Atypical cells are abnormal cells that can be found almost anywhere in the human body. These types of cells generally are cause for concern across a variety of medical fields, including dermatology, gynecology, and hematology. While not all atypical cells are cancerous, some can be caused by inflammation and infection. If the non-cancerous cause of atypical cells is identified and treated, the cells are usually able to revert back to normal.

Cells within the human body are invisible to the naked eye; the only way to identify the cells is by viewing a sample with a microscope. This does not always mean the patient must undergo a biopsy. Cells can be collected by scraping skin, swabbing the throat, conducting a Pap smear, or other non-invasive procedures. To determine if cells are cancerous, a biopsy or tissue sample typically needs to be obtained. Biopsies normally include a local or general anesthetic for the patient and can be taken from almost anywhere on the body.

When atypical cells appear, close follow-up with a physician typically is important. If the doctor does not think the cells are cancerous, he or she may decide to monitor the cells to make sure the area that contains the cells does not spread or increase. Also, this usually will help ensure that the cells themselves do not mutate further.

Non-cancerous causes of atypical cells throughout the body include inflammation and infection. For example, cervical cells will appear atypical in a woman who has a yeast infection. The itchy infection, however, is typically diagnosed well before a tissue sample would need to be taken and analyzed.

When found early enough, some cancers first appear as atypical cells. Certain diseases that are linked to cancer cause precancerous atypical cells, such as human papilloma virus (HPV) and atypical hyperplasia. In the case of HPV, the gynecologist may recommend a colposcopy, which is a close-up view and biopsy of the cervix to see how abnormal and how precancerous the cells are.

Atypical hyperplasia is an accumulation of abnormal cells in the breast duct. Although the affliction is not cancer, if the atypical cells continue to divide or become more abnormal, the condition can change to an early form of carcinoma or non-invasive breast cancer. People who develop atypical hyperplasia are at an increased risk of developing breast cancer and usually are recommended for more frequent screenings.