A new algorithm to assess the risk of malignancy in premenopausal patients with pelvic mass

Abstract

Objective: to elaborate a new algorithm, based on serum CA125, HE4 and age, to assess the risk of malignancy in premenopausal patients with pelvic mass, which performs better than Risk of Ovarian Malignancy Algorithm (ROMA).Materials and methods. The training dataset included 284 premenopausal patients operated because of the presence of pelvic mass, out of which there were 249 patients with benign diseases and 35 patients with malignant or borderline tumors. A novel algorithm, based on serum HE4, CA125 and patient’s age as variables, has been developed. This algorithm was named Risk of Ovarian Cancer Kazan Index (ROCK-I). The validating dataset consisted of 227 consecutively operated premenopausal patients with pelvic mass out of which there were 193 cases of benign diseases, 27 cancers and 7 borderline ovarian tumors (BOT).Results. In the validating dataset ROCK-I and ROMA demonstrated 15 and 30 false positive results respectively. Thus the specificities of ROCK-I and ROMA were 92.2 % and 84.5 %, respectively (р = 0.017). The sensitivities of ROCK-I and ROMA for the joint group of Epithelial ovarian cancers (EOC) (all stages) together with BOT stage IC2–III were 96.3 % and 92.6 %, respectively (p = 0.55). For all malignant disease (all stages) together with BOT stage IC2–III the sensitivities were 90 % and 86.7 %, respectively (p = 0.69). The positive predictive values of ROCK-I and ROMA were 65.1 % and 47.4 %, respectively (p = 0.07). When the scenario of discrimination “benign disease vs the joint group of EOC (all stages) together with BOT stage IC2–III” was used, ROC-AUC of ROCK-I, ROMA and CA125 were 0.988, 0.946 and 0.937. The difference in ROC-AUC between ROCK-I and CA125 was statistically significant (p = 0.01) while the difference between ROMA and CA125 was not (p = 0.79).Conclusion. The proposed ROCK-I has demonstrated greater diagnostic performance than both ROMA and CA125 in the analyzed dataset. If an independent validation shows similar or even slightly lower superiority of ROCK-I over ROMA, it may provide a new basis of routine-use of HE4 in premenopausal patients with pelvic mass.