Adoption of HPV testing as an adjunct to conventional cytology in cervical cancer screening in Japan

Objective

To assess the effectiveness of including HPV testing as an adjunct to conventional cytology in cervical cancer screening.

Methods

Atypical epithelial cells (ATC) were classified according to the 2001 Bethesda classification system. The study ran for 6 years from May 2004 to November 2009 in conjunction with public cervical cancer screening for Kanazawa City residents. Patients with ATC (ASC-US, ASC-H, and AGC) underwent parallel testing for high-risk HPV types with the Hybrid Capture II system; HPV positive and cytology-ATC cases were recalled for colposcopic examination and biopsied if necessary. Results were compared with those obtained before HPV screening was initiated.

Results

A total of 62 645 women underwent screening over the 6-year period; of these, 3622 (5.8%) were ATC positive, among whom 527 (14.5%) tested HPV-positive. These 527 women (0.8% of the screened population) were recalled for colposcopic examination. The resulting 426 biopsies were diagnosed as CIN 1 (n = 187), CIN 2 (n = 53), CIN 3 (n = 11), and invasive cervical cancer (n = 2).

Conclusion

HPV testing as an adjunct to conventional cytology in cervical cancer screening seems to increase detection sensitivity with proven cost-effectiveness.