Purpose: This randomized, controlled trial was designed to determine whether the DNA cytometry testing is superior to the conventional cytologic testing for mass cervical cancer screening.
Experimental design: After approval by the institutional ethics review boards from three separate screening centers, a total of 23,993 Chinese women ages 20 to 65 years were randomly assigned into one of the two groups: a DNA cytometry testing group (11,999 women) and a cytologic testing group (11,994 women). Each woman underwent the other testing after first attending the assigned screening test. Women with positive results after assigned testing additionally underwent colposcopy and human papillomaviruses detections, and those with cervical precancerous or cancerous lesions received appropriate treatment. Sensitivity and specificity estimates were adjusted for verification bias. Analyses were by intention to treat and per protocol ways.
Results: In the cytometric DNA testing group, cervical cancer was diagnosed in 40 subjects, compared with 24 subjects in the cytologic testing group [hazard ratio for the detection of advanced cancer in the DNA cytometry testing group, 0.42; 95% confidence interval (CI), 0.27-0.60]. The sensitivity of the DNA cytometry testing for cervical cancer was 91.7% (95% CI, 64.3-95.8), whereas the sensitivity of cytologic testing was 44.5% (95% CI, 25.2-61.3; P = 0.008). The specificity was 54.1% (95% CI, 31.6-69.0) for DNA cytometry testing and 70.6% (95% CI, 46.8-82.5; P = 0.003) for cytologic testing. The sensitivity of both tests used together was 100%, and the specificity was 91.8%. A total of 187 subjects reported mild to severe adverse events after treatment with positive results in 319 women.
Conclusions: Our results highlight the benefit of the DNA cytometry testing strategy in mass cervical cancer screening with greater sensitivity and positive predicted value than the conventional cytologic testing in developing settings.