Ovarian cancer is usually treated with a chemotherapy drug called cisplatin which works by damaging DNA so much that the tumour cells die. Cisplatin is used to treat a wide variety of tumours in addition to ovarian cancer including, testicular, head and neck and non-small cell lung cancer. In addition, it forms the basis of most combined treatment regimes (where 2 or more drugs are used in combination). The downside to cisplatin is that it is extremely toxic and although some patients benefit substantially from treatment, a large proportion suffer the toxic side effects without any therapeutic benefit. We are aiming to develop a personal test to determine if cisplatin is likely to be effective for an individual’s ovarian cancer, so that the toxic side effects can be avoided if the drug is not going to work.