Development of a tool for prediction of ovarian cancer in patients with adnexal masses: Value of plasma fibrinogen

<div><p>Objective</p><p>To develop a tool for individualized risk estimation of presence of cancer in women with adnexal masses, and to assess the added value of plasma fibrinogen.</p><p>Study design</p><p>We performed a retrospective analysis of a prospectively maintained database of 906 patients with adnexal masses who underwent cystectomy or oophorectomy. Uni- and multivariate logistic regression analyses including pre-operative plasma fibrinogen levels and established predictors were performed. A nomogram was generated to predict the probability of ovarian cancer. Internal validation with split-sample analysis was performed. Decision curve analysis (DCA) was then used to evaluate the clinical net benefit of the prediction model.</p><p>Results</p><p>Ovarian cancer including borderline tumours was found in 241 (26.6%) patients. In multivariate analysis, elevated plasma fibrinogen, elevated CA-125, suspicion for malignancy on ultrasound, and postmenopausal status were associated with ovarian cancer and formed the basis for the nomogram. The overall predictive accuracy of the model, as measured by AUC, was 0.91 (95% CI 0.87–0.94). DCA revealed a net benefit for using this model for predicting ovarian cancer presence compared to a strategy of treat all or treat none.</p><p>Conclusion</p><p>We confirmed the value of plasma fibrinogen as a strong predictor for ovarian cancer in a large cohort of patients with adnexal masses. We developed a highly accurate multivariable model to help in the clinical decision-making regarding the presence of ovarian cancer. This model provided net benefit for a wide range of threshold probabilities. External validation is needed before a recommendation for its use in routine practice can be given.</p></div

Development of a tool for prediction of ovarian cancer in patients with adnexal masses: Value of plasma fibrinogen - Fig 3

<p><b>Calibration plots for assessing the performance of the nomogram to predict ovarian cancer in patients with adnexal masses in (A) the test sample (n = 453) and (B) the validation sample (n = 453).</b> In both (A) and (B), the dashed line represents the ideal reference line where the predicted probabilities estimated from the model would match the observed proportion of patients with ovarian cancer.</p

ROC-curves representing the accuracy for detection of ovarian malignancy in patients with adnexal masses for CA-125, fibrinogen, the full model (including fibrinogen, CA-125, malignancy-criteria on ultrasound), and the model without fibrinogen.

<p>AUC = area under the curve.</p

Pre-operative characteristics in 906 patients who underwent surgery for suspected adnexal masses.

<p>Pre-operative characteristics in 906 patients who underwent surgery for suspected adnexal masses.</p

Decision curve analysis of the effect of the presented nomogram for predicting ovarian cancer in patients with adnexal masses.

<p>Assumption was made that the identification of ovarian cancer would lead to surgery. Net benefit of the presented nomogram is plotted against threshold probabilities for ovarian cancer compared with the strategies of treating all patients with adnexal masses or no one. The nomogram showed an improved net benefit between 5% and 90% threshold probability.</p

Diagnostic performance of serum fibrinogen and CA-125 to detect ovarian malignancy in 906 patients with adnexal masses.

<p>Diagnostic performance of serum fibrinogen and CA-125 to detect ovarian malignancy in 906 patients with adnexal masses.</p