Objective: In Japan, cervical cancer screening consists of a cytology examination performed once every 2 years. We verified whether the risk of cervical intraepithelial neoplasia (CIN) 3 disease or higher (CIN3+) was equivalent to that of cytology negative cases (negative for intraepithelial lesion or malignancy [NILM]) for patients with a cytological diagnosis of “atypical squamous cells of undetermined significance (ASC-US)” who tested negative for human papillomavirus (HPV). Methods: Data from a total of 22,925 cases who had undergone cervical cancer screening at least twice or who had completed follow-up examinations after cervical screening at a single facility between April 2013 and April 2018 were analyzed. The cumulative incidence of CIN3+ was calculated for each category of initial cytology finding and HPV result (NILM, > ASC-US, ASC-US/HPV (unknown), ASC-US/HPV+, and ASC-US/HPV−). The statistical analysis was conducted using the Cox proportional hazards model. Results: The hazard ratio for the cumulative incidence of CIN3+ in 2 years relative to that for NILM cases was 2.7 (95% confidence interval=1.0–7.8) for > ASC-US cases, 0.5 (0.1–1.7) for ASC-US/HPV (unknown), 0.8 (0.3–2.4) for ASC-US/HPV+ cases, and 0.3 (0.1–1.0) for ASC-US/HPV− cases. Conclusion Because the cumulative incidence of CIN3+ at 2 years for the ASC-US/HPV− cases was sufficiently low, compared with that of the NILM cases, we considered it reasonable and safe to perform HPV triage for ASC-US cases and to allow HPV-negative cases to return for their next screening in 2 years, which is the same follow-up schedule as that for NILM cases.

Objective: In 2013, a cohort study aimed to clarify the positive and negative effects of introducing the human papillomavirus (HPV) testing for population-based cervical cancer screening has been launched in Japan. This study included four screenings during the subsequent 7-year follow-up period. We aim to describe the results of the first round of this study on cervical cancer screening here. Methods: This study began in September 2013 with recruitment completed in March 2016.Women aged 30–49 years were divided into 2 groups: those who received uterine cervical cytology alone in the first year (control group), or those who received a combination of cytology and HPV testing (intervention group), based on their age. After first screening, women with positive result of cytology or positive HPV test required referral. We summarized the results of the first round of cervical cancer screening. Results: Of the 25,074 women who were eligible for the study, 13,845 women (55.2%) were screened with cytology alone; 11,229 women (44.8%) received a combination of cytology and HPV testing. After screening, 407 women (2.9%) in the control group and 1,003 women (8.9%) in the intervention group required referral, respectively. Adding HPV testing increased referral rate significantly (p<0.001). Conclusion After first screening, introduction of HPV testing appears to contribute to significantly higher referral rates, suggesting that the number of colposcopies as a detailed examination may increase. These preliminary findings suggest that if HPV testing is introduced into screening, medical institutions need to be prepared for an increasing number of follow-up examinations.

Objective: To examine the effectiveness of progestin re-treatment for recurrent endometrial intraepithelial neoplasia (EIN), atypical endometrial hyperplasia (AH) and endometrial cancer (EC) following initial fertility-sparing treatment. Methods: A comprehensive systematic review and meta-analysis were conducted by an Expert Panel of the Japan Society of Gynecologic Oncology Endometrial Cancer Committee. Multiple search engines, including PubMed/MEDLINE and the Cochrane Database, were searched in December 2021 using the keywords “Endometrial neoplasms,” “Endometrial hyperplasia,” “Endometrial intraepithelial neoplasia,” “Fertility preservation,” “Progestins,” AND “Recurrence.” Cases describing progestin re-treatment for recurrent EIN, AH and EC were compared with cases that underwent conventional hysterectomy. The primary outcomes were survival and disease recurrence, and the secondary outcome was pregnancy. Results: After screening 238 studies, 32 with results for recurrent treatment were identified. These studies included 365 patients (270 received progestin re-treatment and 95 underwent hysterectomy). Most progestin re-treatment involved medroxyprogesterone acetate or megestrol acetate (94.5%). Complete remission (CR) following progestin re-treatment was achieved in 219 (81.1%) cases, with 3-, 6- and 9-month cumulative CR rates of 22.8%, 51.7% and 82.6%, respectively. Progestin re-treatment was associated with higher risk of disease recurrence than conventional hysterectomy was (odds ratio [OR]=6.78; 95% confidence interval [CI]=1.99–23.10), and one patient (0.4%) died of disease. Fifty-one (14.0%) women became pregnant after recurrence, and progestin re-treatment demonstrated a possibility of pregnancy (OR=2.48; 95% CI=0.94–6.58). Conclusion This meta-analysis suggests that repeat progestin therapy is an effective option for women with recurrent EIN, AH and EC, who wish to retain their fertility.