<unk> , in its most general sense, refers to treatment of disease by<unk> hemicals that kill<unk> ells, specifically those of    micro-organisms or<unk> ancer.  In popular usage, it usually refers to antineoplastic drugs used to treat<unk> ancer or the<unk> ombination of these drugs into a standardized treatment regimen.
In its non-oncological use, the term may also refer to antibiotics (antibacterial<unk> . In that sense, the first modern<unk> utic agent was Paul Ehrlich's arsphenamine, an arsenic<unk> ompound discovered in 1909 and used to treat syphilis. This was later followed by sulfonamides discovered by Domagk and penicillin discovered by Alexander Fleming.
Other uses of<unk> ytostatic<unk>  agents (including the ones mentioned below) are the treatment of autoimmune diseases such as multiple<unk> lerosis and rheumatoid arthritis and the suppression of transplant rejections (see immunosuppression and DMARDs).
Chemotherapy
Irradiation
Hormone therapy
Radiation therapy
Adjuvant therapy
External beam radiotherapy
Hormonal therapy 
Neoadjuvant therapy