Targeted Rx. Some tumor cells have markers on their surface and are susceptible to damage by antibodies directed at that marker(s). In some lymphomas antibodies directed at markers present on normal cells are also effective. Usually these are monoclonal antibodies that have been specifically designed for use in humans.
Good targets. Cancer cells "look" different than normal cells; in other words, they display different proteins on their outside compared to normal cells. Antibodies latch onto proteins and can prevent those proteins from functioning, or they can attract the immune system to kill those cancer cells. So that's a quick overview of how antibody therapy can be used to treat cancer.