Morgan RD, McNeish IA, Cook AD, et al. - Given that platinum-based neoadjuvant chemotherapy followed by delayed primary surgery (DPS) represents an established treatment approach for women suffering from newly diagnosed, advanced-stage epithelial ovarian cancer, researchers herein report Response Evaluation Criteria in Solid Tumors, version 1.1 (RECIST) and Gynecologic Cancer InterGroup (GCIG) cancer antigen 125 (CA125) responses in patients undergoing platinum-based neoadjuvant chemotherapy followed by DPS in the ICON8 trial. Participants were women aged 18 years or older with newly diagnosed International Federation of Gynecology and Obstetrics (FIGO; 1988) stage IC–IIA high-grade serous, clear cell, or any poorly differentiated or grade 3 histological subtype, or any FIGO (1988) stage IIB–IV epithelial cancer of the ovary, fallopian tube, or primary peritoneum. Findings revealed lower RECIST-defined radiological response rate compared with that often quoted to patients in the clinic. Experts recommend against using RECIST and GCIG CA125 responses to neoadjuvant chemotherapy for epithelial ovarian cancer as individual predictive markers to stratify patients for whom DPS is possibly beneficial, rather they suggest that these should be used together with the patient's clinical capacity to receive cytoreductive surgery. Solely on the basis of lack of a RECIST or GCIG CA125 response, surgery should not be denied to a patient.