DCS liquid-based system is more effective than conventional smears to diagnosis of cervical lesions : study in high-risk population with biopsy-based confirmation

Abstract

Objective. To compare the performances of Papanicolaou test (PapTest) and of a new liquid-based cytology method, DNA-CitoliqR System (DCS), in a high-risk population, with histology confirmation. Methods. Paired specimens of exfoliated cervical cells were collected under split-sample protocol. All patients were submitted to colposcopy and a biopsy taken when any atypical transformation zone was seen. Sensitivity, specificity, positive and negative predictive values, and overall accuracy of both conventional and DCS methods were computed in relation to histology. Results. A total of 1095 patients were analyzed by two cytology methods and, in 425 (38.8%), histologically. There were significantly more adequate samples with DCS (98.63%) than with conventional (89.6%) smears ( P < 0.001). ASCUS was diagnosed significantly more with DCS than with conventional Pap ( P < 0.001). Conventional Pap misclassified as normal 55.4% (158/285) of cases with either LSIL or HSIL or cancer at histology, whereas DCS misclassified 31.2% (89/285) of cases ( P < 0.001). DCS had a significantly higher sensitivity (70% and 91.3%) than the conventional Pap (49.8% and 72.8%) to detect both LSIL+ and HSIL+ at histology, respectively. On the other hand, specificity of conventional smear (88.2% and 85.2%) was significantly higher than DCS (75.4% and 70.9%) considering both LSIL+ and HSIL+ at histology, respectively. Conclusions. This study confirms the superiority of the liquid-based cytology system DCS to detect cervical lesions. The rate of adequate DSC slides was significantly higher than with conventional cytology.