Development and validation of a prognostic nomogram for overall survival in patients with platinum-resistant ovarian cancer treated with chemotherapy.

•Performance status, ascites, largest tumour size, CA-125, platinum-free interval and platinum resistance predict survival in ovarian cancer.•These factors formed a prognostic nomogram that has been developed and validated in patients who participated in clinical trials.•The prognostic nomogram could be used for stratification of patients in clinical trials and for counselling of patients about survival times.