Currently, ovarian cancer patients are living longer and as the disease tends to remain within the peritoneal cavity without affecting vital organs, patients may maintain a good performance status for a long time. Unfortunately, disease usually relapses. Relapse may be heralded by elevation of CA-125 and eventually symptoms and evidence of disease will appear, leading to treatment of recurrent disease. With patients living longer and receiving therapy for longer periods of time, there is a need for agents that are well tolerated, lacking of cumulative toxicity and able to maintain quality of life rather than worsen it due to unintended side effects.
Treatment at time of relapse has been guided by the interval from the patients prior platinum exposure. Those patients who had demonstrated progression of disease while on platinum-based therapy, or relapsed within six months from their last platinum therapy, were thought to be platinum-resistant and should be treated with other non-cross-resistant agents. Patients who had initially responded and demonstrated clinical progression more than six months after their last platinum therapy were thought to have potentially platinum-sensitive disease and would be re-treated with platinum agents.