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

Are HPV-negative lesions concerned for the introduction of primary HPV testing for cervical cancer screening in Japan?

AIM

In Japan, primary human papilloma virus (HPV) testing has not been introduced for cervical cancer screening due to concerns that HPV-negative lesions may be missed and a lack of Japanese data. The purpose of this study was to evaluate the validity of primary HPV testing in Japan by analyzing cervical intraepithelial neoplasia 2 (CIN2) or more/high-risk HPV- (CIN2+/hrHPV-) cases in cervical cancer screening.

METHODS

Data from 35 525 cervical cancer screenings with HPV testing and cervical cytology from 2011 to 2019 in Saga City, Japan, were reviewed. The cases with low-grade squamous intraepithelial lesion (LSIL+)/hrHPV- were analyzed in detail.

RESULTS

The results of the 35 525 examinees were as follows: 31 123 were negative for intraepithelial lesion or malignancy (NILM)/hrHPV-, 2612 were NILM/hrHPV+, 262 were atypical squamous cells of undetermined significance (ASC-US)/hrHPV-, 213 were ASC-US/hrHPV+, 291 were LSIL+/hrHPV-, and 1024 were LSIL+/hrHPV+. Of the 256 LSIL+/hrHPV- examinees for whom histology was available, CIN2+ were CIN2 9.4% (24/256), CIN3 3.9% (10/256), cervical adenocarcinoma 0.4% (1/256), uterine corpus cancer 1.2% (3/256), and uterine sarcoma 0.4% (1/256). Overall, the rate of LSIL+/hrHPV- was 0.82% (291/35.525), 0.1% (36/35525) of which were cervical lesions with CIN2+. Only one cervical adenocarcinoma was detected, but gastric-type adenocarcinoma was not included.

CONCLUSION

HPV-negative CIN2+ or cervical adenocarcinoma is not a concern for the introduction of primary HPV screening in Japan. Primary HPV testing in cervical cancer screening is considered a feasible method that can be used in Japan, although an algorithm suitable for Japan and a national-level management system need to be established.

Genotype prevalence and age distribution of human papillomavirus from infection to cervical cancer in Japanese women: A systematic review and meta-analysis

BACKGROUND

National HPV vaccination coverage in Japan is less than one percent of the eligible population and cervical cancer incidence and mortality are increasing. This systematic review and meta-analysis aimed to provide a comprehensive estimate of HPV genotype prevalence for Japan.

METHODS

English and Japanese databases were searched to March 2021 for research reporting HPV genotypes in cytology and histology samples from Japanese women. Summary estimates were calculated by disease stage from cytology only assessment - Normal, ASCUS, LSIL, HSIL and from histological assessment - CIN1, CIN2, CIN3/AIS, ICC (ICC-SCC, and ICC-ADC), and other. A random-effects meta-analysis was used to calculate summary prevalence estimates of any-HPV, high-risk (HR) and low-risk (LR) vaccine types, and vaccine genotypes (bivalent, quadrivalent, or nonavalent). This study was registered with PROSPERO: CRD42018117596.

RESULTS

A total of 57759 women with normal cytology, 1766 ASCUS, 3764 LSIL, 2017 HSIL, 3130 CIN1, 1219 CIN2, 869 CIN3/AIS, and 4306 ICC (which included 1032 ICC-SCC, and 638 ICC-ADC) were tested for HPV. The summary estimate of any-HPV genotype in women with normal cytology was 15·6% (95% CI: 12·3-19·4) and in invasive cervical cancer (ICC) was 85·6% (80·7-89·8). The prevalence of HR-HPV was 86·0% (95% CI: 73·9-94·9) for cytological cases of HSIL, 76·9% (52·1-94·7) for histological cases of CIN3/AIS, and 75·7% (68·0-82·6) for ICC. In women with ICC, the summary prevalence of bivalent vaccine genotypes was 58·5% (95% CI: 52·1-64·9), for quadrivalent genotypes was 58·6% (52·2-64·9) and for nonavalent genotypes was 71·5% (64·9-77·6), and of ICC cases that were HPV positive over 90% of infections are nonavalent vaccine preventable. There was considerable heterogeneity in all HPV summary estimates and for ICC, this heterogeneity was not explained by variability in study design, sample type, HPV assay type, or HPV DNA detection method, although studies published in the 1990s had lower prevalence estimates of any-HPV and HR HPV genotypes.

INTERPRETATIONS

HPV prevalence is high among Japanese women. The nonavalent vaccine is likely to have the greatest impact on reducing cervical cancer incidence and mortality in Japan.

What Has Changed Since the Introduction of Human Papillomavirus Testing with the Cytology-Based Cervical Cancer Screening System in Japan A Social Experiment

BACKGROUND

Uterine cervical cancer is the fourth most common female cancer in the world. In Japan, we have an apparently low rate of joining cervical cancer screening programs compared with Western countries. Furthermore, the incidence and mortality rate of cervical cancer among the younger generation has been increasing.

OBJECT

The aim of this study was to assess the effectiveness of cervical cancer screening with human papillomavirus (HPV) testing and cytology in Japan.

METHODS

Collaborating with Saga City government, we initiated a cervical cancer screening system consisting of HPV testing and baseline cervical cytology from April 2011 as a social experiment. A total of 17,284 participants have been screened with this new combination system.

RESULTS

After HPV testing with cytology-based cervical cancer screening, the number of screenings done in women aged under 40 years has significantly increased. In addition, the number of women diagnosed with cervical intraepithelial neoplasia grade 3 has increased (25 of 14,025 vs. 146 of 23,049 under 50 years: p < 0.001).

CONCLUSION

These data suggested that the introduction of HPV testing with cytology-based cervical cancer screening as an adjunct to conventional cytology resulted in better efficiency and more accurate screening among the Japanese population.

Evaluation of p16/Ki-67 dual staining in the detection of cervical precancer and cancer in China

Background This study aimed to evaluate the clinical performance of p16/Ki-67 dual staining in the detection of cervical intraepithelial neoplasia grade 2 or 3 or worse (CIN2+/CIN3+) in Chinese women. Methods Cervical exfoliated cells were collected from 537 eligible women and were used for liquid-based cytology (LBC), p16/Ki-67 dual staining, and human papillomavirus (HPV) DNA testing. All women received colposcopy with biopsies taken at abnormal sites. Histopathological diagnoses were used as the gold standard. Results p16/Ki-67 staining had a positivity rate of 43.58% overall; the rate increased significantly with histological severity (p <0.001). The sensitivities of p16/ki-67 for detecting CIN2+ and CIN3+ were 88.10% and 91.30%, respectively. Compared with high-risk HPV (HR-HPV), sensitivity of p16/Ki-67 was lower for detecting CIN2+ (88.10% versus 95.71%), but similar for detecting CIN3+ (91.30% versus 96.27%). Specificities of p16/Ki-67 were 85.02% for detecting CIN2+ and 76.86% for detecting CIN3+, values similar to those for LBC (84.71% for CIN2+, 80.05% for CIN3+) but higher than those for HR-HPV (62.77% for CIN2+, 71.25% for CIN3+). All the tests performed better in women>30 years. With respect to the performance of triage for women with ASC-US, sensitivities of p16/Ki-67 were 86.36% for detecting CIN2+ and 83.33% for detecting CIN3+, values similar to those of HR-HPV. However, specificities of p16/Ki-67 were both higher than those of HR-HPV (85.96% versus 67.54% for CIN2+, 79.84% versus 62.90% for CIN3+). Conclusion P16/Ki-67 dual staining could probably provide an optional method for China's national cervical cancer screening, and could also be considered as an efficient method of triage for managing women with ASC-US.

Risk of invasive cancer among women visually screened and colposcopy triaged by trained nurses in rural South India

OBJECTIVE

To estimate the long-term risk of cervical cancer among women screened by visual inspection with acetic acid (VIA) and to evaluate the benefit of additional colposcopy triage in rural south India.

METHODS

A retrospective analysis was conducted among 31 343 women who had undergone VIA at Dindigul district, India between January 1, 2000, and August 5, 2003, as part of a randomized screening trial. Women with positive VIA test results were offered colposcopy triage by trained nurses. Cervical cancer incidence data during follow-up (January 1, 2000, to December 31, 2012) were obtained from a regional cancer registry.

RESULTS

Among 3021 screen-positive women free of cancer at baseline, 2974 women underwent colposcopy; colposcopic abnormalities suggestive of precancerous lesions were detected among 2792 of these women (93.9%). Compared with the women with negative VIA screening results, the hazard ratio (HR) of cervical cancer during follow-up among the VIA-positive women without colposcopic abnormalities was 6.5 (95% confidence interval [CI], 1.6-27.1). The risk was similar among VIA-positive women with colposcopic abnormalities but without histological confirmation (HR5.2; 95% CI, 1.9-14.6).

CONCLUSION

The high risk of cancer among women without colposcopic abnormalities who tested positive by VIA suggested that screening without triage is potentially effective.

Single human papillomavirus 16 or 52 infection and later cytological findings in Japanese women with NILM or ASC-US

The relationship between oncogenic human papillomavirus (HPV) infection and later cytological findings in the uterine cervix is unknown in women who were negative for intraepithelial lesion and malignancy (NILM) or atypical squamous cells of undetermined significance (ASC-US). This was investigated in this study in a Japanese population to determine the clinical utility of oncogenic (HPV) genotyping. The relative risk of progressive cytological findings 2 years after identification of oncogenic HPV infection was higher than in cases of non-oncogenic HPV infection (relative risk 3.827; 95% confidence interval (CI): 1.282-11.422), as well as in cases of negative HPV infection (relative risk 2.124; 95% CI: 1.451-3.110). Moreover, the relative risk of progression of cytological findings 2 years later in cases of HPV-16 infection was higher than in cases of HPV-52 infection (relative risk 2.094; 95% CI: 1.005-3.935). Therefore, the initial HPV-DNA genotype may be a potential predictive marker of later progression of cytological findings in the uterine cervix in cases of NILM or ASC-US.

Initial viral load in cases of single human papillomavirus 16 or 52 persistent infection is associated with progression of later cytopathological findings in the uterine cervix

The aim of this study was to investigate the relationship between viral load in single human papillomavirus (HPV) 16 or 52 persistent infection and the progression of later cytopathological findings in the uterine cervix. Cervical cytology and HPV genotyping tests were repeated within 3-6 months in 305 women with oncogenic HPV. Twenty-four cases of single HPV 52 persistent infection and 24 cases of single HPV 16 persistent infection were identified. Cases with later cytopathological findings showing progression were defined as the progression group, while those with no change or regression were the non-progression group. Relative HPV DNA loads were determined by quantitative real-time polymerase chain reaction and expressed relative to human albumin (ALB) DNA. Differences between the two groups were evaluated. The median relative HPV 52 DNA load was 2.211 in the progression group and 0.022 in the non-progression group (Mann-Whitney U-test, P = 0.003). The median relative HPV 16 DNA load was 4.206 in the progression group and 0.103 in the non-progression group (P = 0.001). HPV 52 and 16 DNA loads assessed by quantitative real-time methods may be useful short-term markers for identifying women at high risk for progression of cervical cytological pathology.