Cervical Cancer Screening-Past, Present, and Future.

Cervical cancer screening has undergone a transformation in recent decades. Historically, programs were based on cervical cytology (i.e., "Pap smear"), which had to be repeated often because of its limited sensitivity and reproducibility. In more recent years, the discovery of human papillomavirus (HPV) as the necessary cause of virtually all cervical cancers has led to the introduction of HPV testing into clinical practice, first as a triage test for minor cytologic abnormalities, then in conjunction with cervical cytology (cotesting), and most recently, as a standalone screening test. Multiple randomized trials have shown that HPV-based screening has higher sensitivity compared with cytology, providing great reassurance against cervical precancer and cancer for women testing HPV-negative for many years. Analyses have also been conducted in support of the recent U.S. Preventive Services Task Force guidelines that show that primary HPV screening achieves the greatest balance of benefits and harms compared with other strategies. An added benefit of primary HPV testing is the ability to conduct it from self-collected samples, which is critical for extending coverage among hard-to-reach individuals and could provide a safe and effective alternative to in-person screening visits during the COVID-19 pandemic.See related article by Liang et al., p. 474.