Is cytology/HPV co-testing for cervical cancer screening useful in Japan?

Abstract

In Japan, no region has introduced primary HPV testing for cervical cancer screening. We assessed the diagnostic value and possible harm of HPV testing in Japan. This cross-sectional study with historical controls used cytology-based screening and co-testing data in Japan. As surrogate indicators of possible harm, colposcopy referral rate and cervical intraepithelial neoplasm (CIN) 1 detection rates were calculated. As surrogate indicators with diagnostic values, the detection rates of CIN2 or greater (CIN2+) and CIN3+ were calculated. The data of 297970 women (182697 for cytology-based, 115273 for co-testing) were examined. The detection rates of CIN1, CIN2+, and CIN3+ were significantly higher in the co-testing group than in the cytology-based group (P<0.001, P<0.0001, P<0.01, respectively). Between ages 25-49, CIN2+ detection rates were significantly higher in the co-testing group than in the cytology-based group (P<0.05 for each 5-year age group). Between ages 30-49, CIN3+ detection rates were significantly higher in the co-testing group than in the cytology-based group (P<0.05 for each 5-year age group). Limiting the target age group may minimize the possible harm of screening. Cytology/HPV co-testing may be useful in Japanese populations if balance is maintained between benefit and harm.