Confirmation of the utility of the CA-125 elimination rate (KELIM) as an indicator of the chemosensitivity in advanced-stage ovarian cancer in a "real-life setting"

J Gynecol Oncol. 2024 May;35(3):e34. doi: 10.3802/jgo.2024.35.e34. Epub 2024 Jan 8.

Abstract

Objective: The modeled CA-125 ELIMination rate constant K (KELIM) has been validated as a marker of response to chemotherapy in >12,000 patients with advanced epithelial ovarian carcinoma (EOC) treated in first-line setting enrolled in >12 clinical trials. Patient KELIM is calculable online https://www.biomarker-kinetics.org/presentation. The objective was to investigate the prognostic value of KELIM in a large real-life national cancer registry with non-selected patients.

Methods: We investigated 4,025 EOC patients from the Netherlands Cancer Registry treated with neoadjuvant chemotherapy (NACT) ± followed by interval debulking surgery (IDS). Patient KELIM values were calculated in patients with ≥ 3 CA-125 measurements during NACT. KELIM was standardized with a pre-specified cut-off and scored as unfavorable/favorable (<1.0/≥1.0). KELIM's prognostic value regarding radiological response, completeness of IDS, progression-free survival (PFS), and overall survival (OS) was assessed using univariate/multivariate analyses.

Results: The data from 1,582 patients treated with heterogeneous chemotherapy regimens and sequences were assessable. KELIM was prognostic for radiological response and the likelihood of complete IDS after NACT (odds ratio=2.59; 95% confidence interval [CI]=2.04-3.29). Moreover, KELIM was independently associated with PFS (hazard ratio [HR]=0.76; 95% CI=0.66-0.87), and OS (HR=0.79; 95% CI=0.69-0.91). Combining KELIM with the completeness of the IDS resulted in 3 prognostic groups (satisfactory, intermediate, and poor) with significant OS differences, namely a good, intermediate, and poor survival respectively.

Conclusion: The value of KELIM, as a pragmatic indicator of response to chemotherapy, was maintained in a large real-life population-based cohort, highlighting its applicability in routine conditions.

Keywords: Antigen, CA-125; Kinetics; Models, Theoretical; Ovarian Neoplasms; Prognosis; Survival.

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Antineoplastic Combined Chemotherapy Protocols / therapeutic use
  • Biomarkers, Tumor / blood
  • CA-125 Antigen* / blood
  • Carcinoma, Ovarian Epithelial* / drug therapy
  • Carcinoma, Ovarian Epithelial* / mortality
  • Carcinoma, Ovarian Epithelial* / pathology
  • Carcinoma, Ovarian Epithelial* / therapy
  • Chemotherapy, Adjuvant
  • Cytoreduction Surgical Procedures*
  • Female
  • Humans
  • Middle Aged
  • Neoadjuvant Therapy* / methods
  • Neoplasm Staging
  • Netherlands
  • Ovarian Neoplasms* / drug therapy
  • Ovarian Neoplasms* / mortality
  • Ovarian Neoplasms* / pathology
  • Ovarian Neoplasms* / therapy
  • Prognosis
  • Progression-Free Survival
  • Registries

Grants and funding