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The treatments reviewed previously have, in most cases, been treatments that work in a relatively non specific way. The aim of targeted therapies is to provide a more accurate treatment, by hitting a target as specific as possible to a cancer cell (for example an overactive "go" signal stimulating growth or improved blood supply to a cancer), minimising effects on normal cells. This is an area of active research, and there is likely to be a range of new products available in the future. There are already some of these medications in clinical use, the most well known of which is probably Herceptin (trastuzumab), which may be a useful treatment in some breast cancer patients. Herceptin has a specific target called Her 2, and is a potential treatment option in about 25% of breast cancers.
Although these medications often have very few side effects, they are still not as specific as we would like and can still cause some rare, but potentially serious complications.
The appropriateness, benefits and risks of these medications should be discussed in detail with an oncologist.