cancer
Defenses Against Cancer
Introduction
After a cell becomes cancerous, the Overview of the Immune System is often able to recognize it as abnormal and destroy it before it replicates or spreads. The cancerous cells may be completely eliminated, in which case the cancer never appears. Certain cancers are more likely to progress in people whose immune system is altered or impaired, as in people with AIDS, people receiving medications that suppress the immune system, people with certain 