Article Text
Abstract
Introduction Ovarian cancer (OC) is the deadliest gynecological neoplasm. Surgery is essential but advanced disease requires to initiate with neoadjuvant chemotherapy. Up to 80% of cases will have a response. Different biomarkers have been studied but access is limited. CA 125 elimination rate constant (KELIM), is validated as a biomarker. There is no information in Mexican population.
Methods Retrospective cohort of 151 patients with serous and endometrioid OC FIGO III-IV treated in a reference center in Mexico. KELIM score was calculated using the validated formula at https://www.biomarker-kinetics.org/CA-125-neo. Categorical variables were analyzed with chi-square and multivariable analysis with logistic regression. DFS and OS were analyzed using Kaplan-Meier curves compared with long-rank and multivariate analysis using Cox´s proportional hazard analysis.
Results Mean age was 51 years. Cut-off point of KELIM for complete (R0) surgery was 0.961 (OR 3.33; p=0.05) values equal or above were considered favorable and low as unfavorable. Favorable KELIM was associated with R0 surgery (p=0.041), chemotherapy response score 2 and 3 (p= 0.024), CA 125 values < 35 U/ml post-chemo (p= 0.001). Favorable KELIM was an independent prognostic factor for R0 (OR 2.4, IC 95% 1.08-5.5, p=0.032). Median DFS: 9 vs 28 months (p= 0.226) and median OS: 47 vs 72 months (HR 0.57; IC 95% 0.33-0.98, p= 0.04) for unfavorable and favorable KELIM, respectively.
Conclusion/Implications KELIM is an effective biomarker for complete cytorreduction in OC in Mexican population. Prospective validation trials are required.