Realistic fear of cervical cancer risk in Japan depending on birth year

Effectiveness of catch-up and routine program of the 9-valent vaccine on cervical cancer risk reduction in Japan

In 2013, the national human papillomavirus (HPV) immunization program began. However, in June 2013, Japan's Ministry of Health, Labor and Welfare (MHLW) announced a "temporary" suspension of its recommendation for the human papillomavirus vaccine. Finally, in November 2021, the MHLW ended its suspension of the recommendation of the HPV vaccine. To address the 9-year gap in HPV vaccinations the suspension had caused, the MHLW conducted a program of catch-up vaccinations from April 2022 to March 2025. Finally, in April 2023, the 9-valent HPV vaccine was approved for both the routine and catch-up vaccination programs in Japan. In this study, we investigated the potential effects of the introduction of the 9-valent vaccine on the increased risk of cervical cancer in females born after fiscal year (FY) 2000. We estimated the lifetime relative risk of cervical cancer incidence and death using the improved routine and catch-up vaccination rates after the recent resumption of the governmental recommendation for women and girls to have the HPV vaccination. These relative risks were calculated using a lifetime risk of 1.000 for cervical cancer incidence and death for females born in FY 1993. We predicted that even if a 90% vaccination rate were to be achieved by FY 2024 with the 9-valent vaccine among women born between FY 2000 and FY 2005, the risk would remain higher than for the vaccination generation. Therefore, for women born between FY 2000 and FY 2005, it will be necessary to significantly improve the cervical cancer screening rate to compensate for this increased risk.

Association between administration or recommendation of the human papillomavirus vaccine and primary care physicians' knowledge about vaccination during proactive recommendation suspension: a nationwide cross-sectional study in Japan

OBJECTIVE

The Japanese government suspended the proactive recommendation of the human papillomavirus vaccine (HPVv) in 2013, and the vaccination rate of HPVv declined to <1% during 2014-2015. Previous studies have shown that the recommendation by a physician affects a recipient's decision to receive a vaccine, and physicians' accurate knowledge about vaccination is important to increase vaccine administration. This study aimed to evaluate the association between physicians' knowledge of vaccination and the administration or recommendation of HPVv by primary care physicians (PCPs) in the absence of proactive recommendations from the Japanese government.

DESIGN

Cross-sectional study analysed data obtained through a web-based, self-administered questionnaire survey.

SETTING

The questionnaire was distributed to Japan Primary Care Association (JPCA) members.

PARTICIPANTS

JPCA members who were physicians and on the official JPCA mailing list (n=5395) were included.

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary and secondary outcomes were the administration and recommendation of HPVv, respectively, by PCPs. The association between PCPs' knowledge regarding vaccination and each outcome was determined based on their background and vaccination quiz scores and a logistic regression analysis to estimate the adjusted ORs (AORs).

RESULTS

We received responses from 1084 PCPs and included 981 of them in the analysis. PCPs with a higher score on the vaccination quiz were significantly more likely to administer the HPVv for routine and voluntary vaccination (AOR 2.28, 95% CI 1.58 to 3.28; AOR 2.71, 95% CI 1.81 to 4.04, respectively) and recommend the HPVv for routine and voluntary vaccination than PCPs with a lower score (AOR 2.17, 95% CI 1.62 to 2.92; AOR 1.88, 95% CI 1.32 to 2.67, respectively).

CONCLUSIONS

These results suggest that providing accurate knowledge regarding vaccination to PCPs may improve their administration and recommendation of HPVv, even in the absence of active government recommendations.

Factors Affecting the Cervical Cancer Screening Behaviors of Japanese Women in Their 20s and 30s Using a Health Belief Model: A Cross-Sectional Study

In recent years, the incidence and mortality rates of cervical cancer (CC) have increased among young women. Cervical cancer screening (CCS) is crucial to reducing the incidence and mortality of CC in a country such as Japan, where it is challenging to raise HPV vaccination rates. The purpose of this study was to identify psychological and personal characteristics relating to CCS participation among young people by using the Health Belief Model (HBM). For this cross-sectional study, an internet survey was conducted between February–March 2018. Based on HBM and personal characteristics, χ2 tests and logistic analyses were used to identify factors influencing CCS. Responses obtained from 816 women in their 20s and 30s were used in the analysis. For HBM-based psychological characteristics, the odds ratios were significantly higher for “cues to participation in screening” and “barriers to participation at the time of cancer screening”, while “barriers to participation before cancer screening” showed significantly lower odds ratios. On the other hand, it was found that the presence of children and having regular health checkups affected the attributes of screening that were significant for decision-making. Therefore, it is important to create proactive measures to encourage younger women to undergo medical examinations.

Trends in Pregnancy-Associated Cervical Cancer in Japan between 2012 and 2017: A Multicenter Survey

Large-scale data on maternal and neonatal outcomes of pregnancy-associated cervical cancer in Japan are scarce, and treatment strategies have not been established. This multicenter retrospective observational study investigated clinical features and trends in pregnancy-associated cervical cancer treatments at 523 hospitals in Japan. We included cervical cancer cases that were histologically diagnosed (between 1 January 2012, and 31 December 2017), and their clinical information was retrospectively collected. Of 40 patients diagnosed with pregnancy-associated cervical cancer at ≥22 gestational weeks, 34 (85.0%) were carefully followed until delivery without intervention. Of 163 diagnosed at <22 gestational weeks, 111 continued and 52 terminated their pregnancy. Ninety patients with stage IB1 disease had various treatment options, including termination of pregnancy. The 59 stage IB1 patients who continued their pregnancy were categorized by the primary treatment into strict follow-up, conization, trachelectomy, and neoadjuvant chemotherapy groups, with no significant differences in progression-free or overall survival. The birth weight percentile at delivery was smaller in the neoadjuvant chemotherapy group than in the strict follow-up group (p = 0.029). Full-term delivery rate was relatively higher in the trachelectomy group (35%) than in the other groups. Treatment decisions for pregnancy-associated cervical cancer are needed after estimating the stage, considering both maternal and fetal benefits.

Exploring the relationship between oral high-risk HPV infection and sexual behavior among over 400 medical professionals in Japan

Objectives

This study investigated the relationship between oral high-risk HPV (HR HPV) infection and sexual behavior in Japanese medical professionals.

Materials and methods

We collected oral specimens and a self–administered questionnaire from 234 men and 171 women.

Results

The oral HR HPV infection prevalence was 4.7% (95% confidence interval [CI]: 3.0–7.2]) overall, 7.3% (95% CI: 4.6–11.3) for men, and 1.2% (95% CI: 0.3–4.2) for women. The number of sex partners had a significant influence on this prevalence, with variation by type of sexual behavior. The prevalence of oral HR HPV infection was significantly higher (p < 0.0001) among those with more than 20 lifetime overall sex partners (23.8%, 95% CI: 13.5–38.5) or oral sex partners (25.0%, 95% CI: 14.2–40.2). In terms of the number of vaginal sex partners, the prevalence was approximately the same for those with 6–10 (8.3%, 95% CI: 3.9–17.0), 11–20 (11.1%, 95% CI: 5.2–22.2), or more than 20 (11.5%, 95% CI: 4.0–29.0) partners (p = 0.0043). Furthermore, dividing the number of vaginal and oral sex partners into four categories (both>5, only vaginal>5, only oral>5, and both≤5), the infection prevalence was significantly higher when both vaginal and oral sex partners were more than five (12.5%, 95% CI: 7.7–19.6). The prevalence was also higher for those who had more oral than vaginal partners, compared with other groups (13.5%, 95% CI: 6.7–25.3).

Conclusions and clinical relevance

Oral HR HPV infection in Japan seems to be influenced by sexual behavior, and preventive health efforts such as vaccination and health education should be implemented.

Challenge to improve Japan's deplorable HPV vaccination rate by local government actions

AIM

In Japan, in 2013, following reports of several alleged adverse reactions in young girls following vaccination, the previously successful national human papillomavirus infection (HPV) vaccination program collapsed rapidly. In the 8 years since vaccination rates have hovered near zero. In October of 2020, in an attempt to mitigate this lingering disaster, the Japanese Ministry of Health, Labor, and Welfare (MHLW) agency finally revised its HPV vaccination informational leaflet that was designed to be distributed by local governments nationwide. Prior to this revision, Toyonaka City, in Japan's Osaka province, had already begun sending out their own unique leaflet to girls in the targeted 6th-10th grades. As a preview of how MHLW's revised leaflet might eventually succeed, we have studied the HPV vaccination results from Toyonaka City's experiment.

METHOD

This study was a population-based analysis that compared the monthly rates of new vaccinations in girls of a targeted grade school age group. We looked at rates before and after the leaflets were sent by Toyonaka City's Division of Health Promotion and Senior Services.

RESULTS

The vaccination rates between April 2020 and March 2021 were improved across all grades; 1.2% in 6th grade (p = 0.000185), 2.5% in 7th grade (p < 0.0001), 3.5% in 8th grade (p < 0.0001), 6.8% in 9th grade (p < 0.0001), and a remarkable 16.5% in 10th grade (p < 0.0001).

CONCLUSION

When a local government sends an HPV informational leaflet targeted at young girls, it can significantly improve their HPV vaccination rates.

Trends in cervical cancer incidence and mortality of young and middle adults in Japan

In most high‐resource countries with organized screening programs, the incidence and mortality of cervical cancer is decreasing. Recent statistics have also revealed a reduction in invasive cervical cancer incidence as a result of national vaccination programs. Paradoxically, cervical cancer incidence has increased in Japan, particularly amongst women of reproductive age. This study aimed to examine the trends in cervical cancer incidence and mortality for young and middle adult women in Japan, by analyzing trends in 10‐year interval age‐groups. Cervical cancer incidence for young and middle adult women (ages 20‐59 years) was obtained from high‐quality population‐based cancer registries in three prefectures from 1985 to 2015. National cancer mortality data were obtained from published vital statistics from 1985 to 2019. Trends in crude and age‐standardized rates (ASR) were analyzed using Joinpoint regression. The cervical cancer incidence trend in 20‐59‐year‐old women combined significantly increased over the observation period. Both crude and ASR increased from 1985 to 2015 with an annual percent change (APC) of +1.6% (95% confidence interval, 1.1, 2.1) and +1.7% (1.2, 2.3), respectively. Similar increases were seen in ages 20‐29, 30‐39, and 40‐49 years with higher APCs especially in 20s and 30s. Both crude and ASR mortality significantly increased after the early 1990s in ages 20‐59 years combined. Based on the recognition that current cervical cancer control strategies in Japan have not been effective in reducing the cervical cancer burden in young and middle adults, promotion of screening and vaccination should be urgently strengthened.

Changes in HPV16/18 Prevalence among Unvaccinated Women with Cervical Intraepithelial Neoplasia in Japan: Assessment of Herd Effects following the HPV Vaccination Program

Since the human papillomavirus (HPV) vaccination program for Japanese girls aged 12–16 years began in 2010, vaccination uptake has been low in women born before 1993 but high (approximately 70%) in those born during 1994–1999. We previously compared the prevalence of vaccine types HPV16 and HPV18 in cervical intraepithelial neoplasia grade 1–3 (CIN1–3) or adenocarcinoma in situ (AIS) between vaccinated and unvaccinated cohorts and found direct protection effects among vaccinated women in Japan. In this study, we focused on changes in HPV16/18 prevalence among “unvaccinated” cohorts with CIN/AIS. We analyzed HPV16/18 prevalence among 5051 unvaccinated women aged <40 years, newly diagnosed with CIN/AIS during 2012–2021 for time trends. Declining trends in HPV16/18 prevalence over 9 years were observed in CIN1 (36.0–10.0%, Ptrend = 0.03) and CIN2–3/AIS (62.5–36.4%, Ptrend = 0.07) among women aged <25 years. HPV16/18 prevalence in CIN1 and CIN2–3/AIS diagnosed at age 20–24 years was lower in 1994–1999 birth cohorts compared with 1988–1993 birth cohorts (4.5% vs. 25.7% for CIN1 and 40.0% vs. 58.1% for CIN2–3/AIS, both p = 0.04). Significant reduction in HPV16/18 prevalence among young unvaccinated women with CIN1 and CIN2–3/AIS suggests herd effects of HPV vaccination in Japan.

HPV vaccine effectiveness by age at first vaccination among Japanese women

In Japan, the National Immunization Program against human papillomavirus (HPV) targets girls aged 12‐16 years, and catch‐up vaccination is recommended for young women up to age 26 years. Because HPV infection rates increase soon after sexual debut, we evaluated HPV vaccine effectiveness by age at first vaccination. Along with vaccination history, HPV genotyping results from 5795 women younger than 40 years diagnosed with cervical intraepithelial neoplasia grade 2‐3 (CIN2‐3), adenocarcinoma in situ (AIS), or invasive cervical cancer were analyzed. The attribution of vaccine‐targeted types HPV16 or HPV18 to CIN2‐3/AIS was 47.0% for unvaccinated women (n = 4297), but 0.0%, 13.0%, 35.7%, and 39.6% for women vaccinated at ages 12‐15 years (n = 36), 16‐18 years (n = 23), 19–22 years (n = 14), and older than 22 years (n = 91), respectively, indicating the greater effectiveness of HPV vaccination among those initiating vaccination at age 18 years or younger (P < .001). This finding was supported by age at first sexual intercourse; among women with CIN2‐3/AIS, only 9.2% were sexually active by age 14 years, but the percentage quickly increased to 47.2% by age 16 and 77.1% by age 18. Additionally, the HPV16/18 prevalence in CIN2‐3/AIS was 0.0%, 12.5%, and 40.0% for women vaccinated before (n = 16), within 3 years (n = 8), and more than 3 years after (n = 15) first intercourse, respectively (P = .004). In conclusion, our data appear to support routine HPV vaccination for girls aged 12‐14 years and catch‐up vaccination for adolescents aged 18 years and younger in Japan.

Educational intervention for women in Japan coming of age for cervical cancer screening who grew up during the suspended HPV-vaccination-program

Girls born in 2001 became eligible for subsidized HPV vaccination when they reached 12 years old in 2013, but that was the year when the Japanese MHLW suspended its official governmental recommendation for HPV vaccination. Those girls will now reach 20 years of age this year, 2021, and they will become eligible for cervical cancer screening. We report on the effects of an educational intervention with an information sheet about their current unvaccinated defenselessness for HPV and the necessity for early and repeated cervical cancer screening as a way to improve their intention to have that screening and their attitude toward HPV vaccination. Among the educated women, 75.2% had a positive intention toward having cervical cancer screening, 24.8% had a negative intention. Educational intervention can significantly promote the intention of having cervical cancer screening in women who had experienced the suspension of the MHLW's official recommendation for HPV vaccination. As a result of this simple intervention, they were more likely to think that HPV vaccination was needed for themselves.

P16INK4A expression might be associated with a favorable prognosis for cervical adenocarcinoma via dysregulation of the RB pathway

Previous studies have largely failed to clarify the relationship between p16^INK4A status and cervical adenocarcinoma prognosis. The current study aimed to examine the clinical and pathological significance of p16^INK4A expression in several cervical adenocarcinoma subtypes. Eighty-two samples collected from patients with cervical adenocarcinoma were formalin fixed and paraffin embedded. Next, p16^INK4A levels were analyzed with immunohistochemistry. Additionally, the relationship between p16^INK4A expression and clinicopathological factors as well as prognosis was evaluated. The expression of p16^INK4A was mostly detected in all usual cervical adenocarcinoma subtypes. In the gastric type, only a few cases were positive for p16^INK4A expression. Results of the Kaplan–Meier analysis indicated that the positive p16^INK4A expression in tumor cells was significantly associated with favorable progression-free survival and overall survival in patients with cervical adenocarcinoma (p = 0.018 and p = 0.047, respectively, log-rank test). Our findings suggest that the status of p16^INK4A expression may influence prognosis. Thus, p16^INK4A expression could be used as a biomarker for improving the prognosis of patients with cervical adenocarcinoma.

Ten-year questionnaire study on human papillomavirus vaccination targeting new female medical school students: Follow-up to the 2015 report

AIM

We aimed to conduct a fixed-point observation questionnaire survey of changes in young women's human papillomavirus (HPV) vaccination status over the course of 10 years. We also investigated the influence of suspension of governmental recommendation for HPV vaccination since June 2013.

METHODS

During 2011-2020, we conducted a self-completed questionnaire survey among newly enrolled female medical school students in Yokohama, Japan. The questionnaire featured items regarding HPV vaccination status, age, previous sex education, and knowledge about cervical cancer and HPV vaccination.

RESULTS

HPV vaccine uptake rates in 2011 (5.4%) and 2012 (13.5%), when vaccination was self-funded, increased after 2013 (48.7%), when vaccination fees were subsidized. The rate dropped drastically in 2019 (14.3%) and 2020 (5.1%), after suspension of recommendation by the government. Comparisons between new students in 2015/2016, who had high vaccination rates (65.2%), and new students in 2019/2020, who had low vaccination rates (9.8%), showed decreased levels of HPV vaccination awareness, with fewer students having covered cervical cancer prevention in sex education and with respondents having less knowledge about the details of HPV vaccination.

CONCLUSIONS

After the suspension of proactive HPV vaccine recommendation, markedly fewer students have been vaccinated against HPV, even those at the vaccination target age. This situation has substantially influenced the lower awareness about cervical cancer prevention, even among medical school students. To protect young women from cervical cancer in Japan, it is crucial for the government to resume proactive recommendation of HPV vaccines as soon as possible.

The last strategy for re-dissemination of HPV vaccination in Japan while still under the suspension of the governmental recommendation

In Japan, the governmental recommnendation of HPV vaccine has been suspended since June 2013, due to media reports of alleged adverse vaccination events. Although evidence of effectiveness and safety of the HPV vaccine has been universally demonstrated, and the medical and academic organizations across Japan have requested the resumption of the government’s recommendation, the Japanese government has not changed their official stance towards the HPV vaccine. Under the current suspension of the national government’s recommendation, one local government Isumi City started sending a leaflet containing information of cervical cancer and HPV vaccine, but not recommendation for the vaccine, to the tagted girls born in the fiscal year (FY) 2003. The cumulative vaccination rate of them reached 10.07% (14/139), which was significantly higher than that (0.00%) for girls born in FY 2002 who did not receive such a leaflet (p < 0.001). We sincerely ask the national government to change their stance towards the HPV vaccine. We also strongly suggest that, in the meantime, local governments immediately begin to provide an appropriate information of cervical cancer and HPV vaccine to the targeted girls and their parents in a way similar to what Isumi City has now shown to be effective.

Potential for cervical cancer incidence and death resulting from Japan's current policy of prolonged suspension of its governmental recommendation of the HPV vaccine

In 2013, recurrent reports of diverse symptoms occurring in girls after receiving HPV vaccination appeared in Japanese media. The Ministry of Health, Labor and Welfare quickly responded by announcing a temporary suspension of its recommendation for the vaccine. The HPV vaccination rate soon fell to almost zero. In the present study, we calculated the potential future numbers of cervical cancer incidence and death that will be increased by this policy decision. We have assumed that the number of yearly vaccinations is evenly distributed across a daily basis. Future incidence and death increased in females born in FY2000 are estimated to be 3651 and 904, respectively, 4566 and 1130 for those born in FY2001, 4645 and 1150 for those born in FY2002, and 4657 and 1153 for those born in FY2003. In FY2020, the large increase of risks to females born in FY2004 amounts to 12.0 females per day who will now be at a higher risk for acquiring of cervical cancer in their future, and 3.0 females per day newly at risk for future death from that disease in its progressive form. No one should be able to accept this situation. We sincerely ask the government to resume its recommendation for the vaccine as soon as possible.

Japanese Mothers' Intention to HPV Vaccinate Their Daughters: How Has It Changed over Time Because of the Prolonged Suspension of the Governmental Recommendation?

The trend for cervical cancer in younger women has been increasing recently in Japan. However, as a result of the suspension of governmental recommendation, Japan’s HPV (human papillomavirus) vaccination rate for girls born since 2000 has dropped sharply. We conducted an internet survey in December of 2019, 76 months after the suspension of recommendation, to verify the intention of mothers to inoculate their daughter under current circumstances and compared with our previous surveys and leaflet intervention effect. The rates of mothers who replied that they would “inoculate” were significantly higher at 9 and 23 months, but by 32 months after the suspension the rate was significantly lower (p < 0.05, p < 0.05, p < 0.05, respectively). The rates of the mothers who replied they would not inoculate were significantly lower at 9 months and 23 months, but at 76 months was significantly higher (p < 0.05, p < 0.05, p < 0.05, respectively). We found that intervention with a leaflet that could be used under the current suspension of the governmental recommendation did not increase the mothers’ intention to inoculate their daughters. A leaflet that actively encourages vaccination may increase the intent of vaccination. It is strongly recommended that the MHLW promptly resume its recommendations for HPV vaccination.

Post-hoc analysis of injection-site reactions following vaccination with quadrivalent human papillomavirus vaccine in Japanese female clinical trial participants

AIM

The quadrivalent human papillomavirus (4vHPV) vaccine has demonstrated efficacy and immunogenicity and was generally well tolerated in clinical trials conducted in Japan. We report a detailed safety analysis of injection-site reactions in female Japanese 4vHPV clinical trial participants.

METHODS

This post-hoc analysis included data from 2 double-blind, placebo-controlled phase II clinical trials of a 3-dose (Day 1, Month 2, Month 6) regimen of 4vHPV vaccine in Japanese young women aged 18-26 years (N = 1021; NCT00378560) and girls aged 9-17 years (N = 107; NCT00411749). Injection-site and systemic adverse events (AEs) were monitored using vaccination report cards for 15 days after each vaccine dose; serious AEs were reported throughout the trials. Post-hoc analyses of data from these trials were performed to examine details of injection-site AEs, including day of onset, time from onset to resolution, and maximum intensity.

RESULTS

Injection-site AEs were reported by 85.6% of 4vHPV vaccine recipients and 72.4% of placebo recipients, most commonly erythema, pain, pruritus, and swelling (each >5% of 4vHPV vaccine recipients). The majority of injection-site AEs had an onset within 3 days of vaccination and were mild to moderate in intensity; few 4vHPV vaccine recipients reported severe injection-site AEs (2.0% overall). All injection-site AEs resolved, and most (4vHPV: 87.5%; placebo: 92.7%) resolved within 5 days of onset.

CONCLUSIONS

Most injection-site reactions are mild or moderate in intensity and of short duration. The 3-dose regimen of 4vHPV vaccine is well tolerated in Japanese female clinical trial participants based on this post-hoc analysis. These results will further support safety communication between healthcare providers and vaccine recipients regarding the HPV vaccine.

TRIAL REGISTRATION

Clinicaltrials. gov: NCT00378560 and NCT00411749.

Changing attitudes in Japan toward HPV vaccination: a 5-year follow-up survey of obstetricians and gynecologists regarding their current opinions about the HPV vaccine

In Japan, the governmental recommendation for HPV vaccination was suspended in June 2013 because of media reports of so-called adverse vaccine events. The HPV vaccination rate in Japan prior to this suspension was almost 70%, but fell afterward to almost zero. To explore ways to bolster HPV vaccination, between 2014 and 2019 we conducted three serial surveys of the opinions of obstetricians and gynecologists about HPV vaccination. This study aimed to discuss the changing attitudes found in this 5-year follow-up survey. In August 2014, January 2017, and June 2019, we posted questionnaires to about 570 obstetricians and gynecologists practicing in Osaka, Japan. All three surveys used the same structured and closed-ended questionnaire, including questions about their personal opinions regarding HPV vaccination. We compared our new results to those of the previous two surveys. The response rate for the latest survey was 51.1% (293/573), which was equivalent to the previous two surveys. Among the responders, 83.3% (244/293) now thought that the Japanese government should restart its HPV vaccine recommendation, and 84.6% (248/293) were already recommending HPV vaccines for teenagers in their daily care. Eleven of 30 doctors (36.7%) had their own teenage daughters vaccinated against HPV after the suspension of recommendation. The rate has maintained an increasing trend from the previous two surveys. This study indicated that the attitude of obstetricians and gynecologists in Japan toward HPV vaccination has changed positively over 5 years. The results should serve as an encouragement to resume the governmental recommendation of HPV vaccines.

Japan's Ongoing Crisis on HPV Vaccination

The Japanese government suspended proactive recommendations for the HPV vaccine in June 2013. The suspension is now in its seventh year, despite all the data pointing to the safety of the HPV vaccine. We reported a high vaccine effectiveness in the group of women vaccinated before their first intercourse (93.9%). The prevalence of cross-protected types of HPV 31/45/52 was also lower in the vaccinated group, and the vaccine effectiveness was 67.7%. Furthermore, prevalence of HPV16, 31 and 52 infection rates in the vaccinated group were obviously lower than that in the unvaccinated group, and no one had HPV18 or 45 infection in the vaccinated group. The addition of a cross-protective effect toward HPV types 31/45/52 to HPV types 16/18, which is the direct target of the bivalent HPV vaccine, may possibly prevent around 82% of invasive cervical cancer cases in Japan. With regard to the preventive effect of histological abnormalities, we also reported significant reduction in incidence of cervical intraepithelial neoplasia (CIN)3 or worse. Thus, the efficacy of the vaccine has been demonstrated for precancerous disease, and the diverse symptoms after HPV vaccination are likely functional somatic. For the future of Japanese girls, there is a need to resume the proactive recommendation of HPV vaccination and for immediate action to be taken by the Japanese government.

A survey of Japanese mothers on the effectiveness of the Ministry of Health, Labor and Welfare's revised HPV vaccine leaflet

Introduction: In June of 2013, Japan’s Ministry of Health, Labor and Welfare (MHLW) suspended its position of strong recommendation for the routine immunization of young girls against the Human Papilloma Virus (HPV) because of reports of adverse reactions after the vaccination. For the next four years, the MHLW’s website warned about the significance of these adverse events. In January of 2018, MHLW’s website was modified to reflect a less negative stance. We have studied public awareness of MHLW’s revised leaflet in Japanese women whose daughters were of the targeted age for receiving the HPV vaccine and how this awareness influenced their intentions to get their daughters vaccinated.

Materials and Methods: From June to December of 2018, a survey was conducted through the Departments of Obstetrics and Gynecology at 14 different medical facilities. The questionnaire was distributed to women whose daughters were of the HPV–vaccine-targeted age. The survey measured their responses before and after being presented with the 2018-revised MHLW leaflet. Responses from 384 mothers were analyzed.

Results: Before being presented with the leaflet, the survey found that the percentage of responder’s daughters already vaccinated was 6.5% (24/372). After reading the MHLW leaflet, an additional 6.9% (24/346) responded “I want to get my daughter vaccinated immediately”, and 37.6% (130/346) responded “I have positive feelings about HPV vaccination”.

Discussion: By presenting the new MHLW leaflet at obstetrics and gynecology facilities, we expect to be able to effectively increase the HPV vaccination rate in Japan.

Bivalent Human Papillomavirus Vaccine Effectiveness in a Japanese Population: High Vaccine-Type-Specific Effectiveness and Evidence of Cross-Protection

Background

Proactive recommendations for human papillomavirus (HPV) vaccines in Japan have been suspended for 5 years because of safety concerns. While no scientific evidence exists to substantiate these concerns, one reason given for not reinstating recommendations is the lack of reliable vaccine effectiveness (VE) data in a Japanese population. This study reports the VE of the bivalent HPV vaccine in Japanese women aged 20–22 years.

Methods

During cervical screening between 2014 and 2016, women had Papanicolaou smears and HPV tests performed and provided data about their sexual history. Estimates of VE for vaccine-targeted HPV type 16 (HPV16) and 18 and cross-protection against other types were calculated.

Results

Overall, 2197 women were tested, and 1814 were included in the analysis. Of these, 1355 (74.6%) were vaccinated, and 1295 (95.5%) completed the 3-dose schedule. In women sexually naive at vaccination, the pooled VEs against HPV16 and 18 and for HPV31, 45, and 52 were 95.5% (P < .01) and 71.9% (P < .01), respectively. When adjusted for number of sex partners and birth year, pooled VEs were 93.9% (P = .01) and 67.7% (P = .01) for HPV16 and 18 and HPV31, 45, and 52, respectively.

Conclusions

The bivalent HPV vaccine is highly effective against HPV16 and 18. Furthermore, significant cross-protection against HPV31, 45, and 52 was demonstrated and sustained up to 6 years after vaccination. These findings should reassure politicians about the VE of bivalent HPV vaccine in a Japanese population.

Reduction in HPV16/18 prevalence among young women with high-grade cervical lesions following the Japanese HPV vaccination program

The Japanese government began a human papillomavirus (HPV) vaccination program for girls aged 12‐16 years in 2010 but withdrew its recommendation in 2013 because of potential adverse effects, leading to drastically reduced vaccination uptake. To evaluate population‐level effects of HPV vaccination, women younger than 40 years of age newly diagnosed with cervical intraepithelial neoplasia grade 1‐3 (CIN1‐3), adenocarcinoma in situ (AIS), or invasive cervical cancer (ICC) have been registered at 21 participating institutes each year since 2012. A total of 7709 women were registered during 2012‐2017, of which 5045 were HPV genotyped. Declining trends in prevalence of vaccine types HPV16 and HPV18 during a 6‐year period were observed in CIN1 (50.0% to 0.0%, P_trend < .0001) and CIN2‐3/AIS (83.3% to 45.0%, P_trend = .07) only among women younger than 25 years of age. Overall, HPV vaccination reduced the proportion of HPV16/18‐attributable CIN2‐3/AIS from 47.7% to 33.0% (P = .003): from 43.5% to 12.5% as routine vaccination (P = .08) and from 47.8% to 36.7% as catch‐up vaccination (P = .04). The HPV16/18 prevalence in CIN2‐3/AIS cases was significantly reduced among female individuals who received their first vaccination at age 20 years or younger (P = .02). We could not evaluate vaccination effects on ICC owing to low incidence of ICC among women aged less than 25 years. We found HPV vaccination to be effective in protecting against HPV16/18‐positive CIN/AIS in Japan; however, our data did not support catch‐up vaccination for women older than 20 years. Older adolescents who skipped routine vaccination due to the government’s suspension of its vaccine recommendation could benefit from receiving catch‐up vaccination before age 20 years.

Cervical cancer screening rate differs by HPV vaccination status: An interim analysis

BACKGROUND

The incidence of cervical cancer has been increasing, especially in younger generation, in Japan. The females born between 1994 and 1999, who achieved rates of HPV vaccination approaching 70%, have become the target of cervical cancer screening programs. Here, we have analyzed the cervical cancer screening rates among the vaccinated and unvaccinated women.

METHODS

The survey data for cervical cancer screening at age 20 in FY 2015 was derived from two cities, Toyonaka and Iwaki.

RESULTS

Among 2,727 females, in Toyonaka and Iwaki, who were born in FY 1995 and targeted in FY 2015 at age 20 for cervical cancer screening, their HPV vaccination rate was 64.2% (1,753/2,727). The screening rate was 6.4% (112/1,753) in the vaccinated and 3.9% (38/974) in the unvaccinated. This difference was statistically significant (p < 0.01).

CONCLUSIONS

We have demonstrated that HPV-vaccinated females tended to be effectively protected from future cervical cancer than the unvaccinated.

Newspaper coverage before and after the HPV vaccination crisis began in Japan: a text mining analysis

Background

The human papillomavirus (HPV) vaccination coverage rate has fallen sharply in Japan since 2013, when newspapers began covering negative campaigns against the vaccination. We examined and compared contents from newspaper articles before and after the start of this HPV vaccination crisis.

Methods

We collected articles published between January 2005 and September 2017 in the four daily national Japanese newspapers with the highest domestic circulation. We then conducted text mining analysis to chronologically examine content distribution.

Results

From among the 1178 articles analyzed, 12 types of contents were identified. Contents related to cervical cancer prevention, such as on the risk of developing cervical cancer, causes of cervical cancer, and the effects of vaccination, were frequently conveyed until 2012. However, after March 2013, they were replaced with anti-vaccination contents, such as on adverse effects to vaccines, alleged victims, and related lawsuits. Meanwhile pro-vaccination contents, such as safety statements from the World Health Organization, scarcely received coverage.

Conclusions

Newspaper contents changed profoundly before and after the start of the vaccination crisis. Those newspaper reports potentially had impact on readers’ beliefs and actions. Journalists should strive for impartial coverage so readers can make more-informed decisions. Health professionals should be expected to work with journalists to help improve impartiality in newspaper coverage. The Ministry of Health, Labour and Welfare should discus benefits and risks of the HPV vaccination based on the scientific evidences, and consider to resume the proactive recommendation of HPV vaccination. Well-organized advocacy among medical societies, scientists and health professionals will also be needed to influence the government.

Evaluation of future cervical cancer risk in Japan, based on birth year

In 2013, following the Ministry of Health, Labor and Welfare (MHLW)'s announced suspension of its vaccine recommendation due to media reports of "adverse events", HPV vaccination dropped to almost 0%. Here, we analyzed, by birth year, the cumulative vaccinations for girls up to age 16 (maximum age for public subsidies) and the results of cervical cancer screening in Matsuyama City. The incidence of CIN3 or worse was 0.09% (7/7872) for these unvaccinated generation born between 1991 and 1993, and 0.00% (0/7389) for the vaccination generation born between 1994 and 1996. This study is the first to show the significant reduction in incidence of CIN3+depending on birth year in Japan. We must keep in mind that the unacceptable high risk for cervical cancer has already begun for an entire new generation of unvaccinated girls born in or after 2000. This data encourages a resumption of MHLW's recommendation for HPV vaccination.

The Safety and Effectiveness of Abdominal Radical Trachelectomy for Early-Stage Cervical Cancer During Pregnancy

OBJECTIVES

Cervical cancer is one of the most frequently diagnosed cancers in pregnancy. Our aim was to evaluate the safety and efficacy of abdominal radical trachelectomy (ART) for pregnant women with early-stage cervical cancer who strongly desire to preserve their pregnancies.

METHODS/MATERIALS

A retrospective observational study was performed for stage IB1 cervical cancer patients who underwent ART or radical hysterectomy (RH) at our hospital between February 2013 and June 2017. We compared differences in perioperative findings and oncologic outcomes among ART during pregnancy (ART-DP), ART, and RH groups.

RESULTS

A total of 38 patients were included in this analysis. Six, 10, and 22 patients were assigned to the ART-DP, ART, and RH groups, respectively. There were no significant differences in the distribution of pathological TNM classifications, histology, tumor size, stromal invasion, and lymph-vascular space invasion among the 3 groups. The patients in the ART-DP group were younger than those in the RH group (P = 0.014). The ART-DP group was associated with more blood loss and prolonged surgery compared with the RH group (P = 0.017 and P = 0.014). The number of total lymph nodes in the ART-DP group was lower than that in the RH group (P = 0.036). However, there were no significant differences in age, surgical time, blood loss, or lymph node count between the ART-DP and ART groups. There were no significant differences in progression-free and overall survival times among the 3 groups, and no recurrence was observed in the ART-DP group.

CONCLUSIONS

Abdominal radical trachelectomy may be a tolerable treatment option for pregnant women with early-stage cervical cancer who strongly desire a baby.

A Japanese survey of malignant disease in pregnancy

BACKGROUND

In recent years, the incidence of malignant disease in pregnancy has been increasing, but there are few large-scale surveys of malignant disease in pregnancy in Japan. The aim of this study was to survey malignant disease occurring during pregnancy in Japan.

METHODS

Malignant disease in pregnancy was defined as diagnosis or treatment for malignant disease, except in situ carcinoma during pregnancy, or within 1-year postpartum. First, a primary survey questionnaire of the incidence of malignant disease in pregnancy and the number of deliveries over the course of 2014 was sent to 510 medical centers in Japan. Second, the survey questionnaires on the incidence of malignant diseases in pregnancy were collected and analyzed in detail.

RESULTS

Of the 510 medical centers, 411 (81%) responded to the survey. There were 215,372 deliveries and 189 incidents (0.09%) of malignant disease in pregnancy. Of the 189 patients with malignancy, 157 detailed responses about the patients were received. The most frequently encountered cancer types were cervical cancer (36%), breast cancer (24%), and ovarian cancer (15%). During the 2 years after delivery, 15 patients (1 with breast cancer, 2 with ovarian cancer, 3 with hematologic malignancy, 4 with intestinal cancer, and 5 with others) died of the disease; most of them had advanced disease. In particular, 88% of the patients with intestinal cancers at diagnosis had advanced disease, and half of them died of disease.

CONCLUSIONS

In Japan, the most common malignancies in pregnancy in order of frequency are cervical cancer, breast cancer, and ovarian cancer. Early diagnosis and appropriate management of cancer during pregnancy are important for improving maternal and neonatal outcomes, because advanced diseases have a poor prognosis.

Public subsidies and the recommendation of child vaccines among primary care physicians: a nationwide cross-sectional study in Japan

OBJECTIVE

Although public subsidies and physician recommendations for vaccination play key roles in increasing childhood vaccination coverage, the association between them remains uncertain. This study aimed to identify the association between awareness of public subsidies and recommendations for Haemophilus influenzae type b (Hib), Streptococcus pneumoniae (pneumococcal conjugate vaccine (PCV)) and human papillomavirus (HPV) vaccinations among primary care physicians in Japan.

DESIGN

This is a cross-sectional study.

SETTING

In 2012, a questionnaire was distributed among 3000 randomly selected physicians who were members of the Japan Primary Care Association.

PARTICIPANTS

From the questionnaire, participants were limited to physicians who administered childhood vaccinations.

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary measures were participants' awareness of public subsidies and their recommendation levels for Hib, PCV and HPV vaccines. Multiple logistic regression analysis was performed to investigate the association between awareness and recommendation, with adjustment for possible confounders.

RESULTS

The response rate was 25.8% (743/2880). Of 743 physician respondents, 434 were included as analysis subjects. The proportions of those who recommended vaccinations were 57.1% for Hib, 54.1% for PCV and 58.1% for HPV. For each vaccine, multivariable analyses showed physicians who were aware of the subsidy were more likely to recommend vaccination than those who were not aware: the adjusted ORs were 4.21 (95% CI 2.47 to 7.15) for Hib, 4.96 (95% CI 2.89 to 8.53) for PCV and 4.17 (95% CI 2.00 to 8.70) for HPV.

CONCLUSIONS

Primary care physicians' awareness of public subsidies was found to be associated with their recommendations for the Hib, PCV and HPV vaccines. Provision of information about public subsidies to these physicians may increase their likelihood to recommend vaccination.

HPV vaccination in Japan: results of a 3-year follow-up survey of obstetricians and gynecologists regarding their opinions toward the vaccine

Background

In Japan, the cervical cancer preventative HPV vaccination rate has dramatically declined, directly as a result of repeated broadcasts of so-called adverse events and the resulting suspension of the government’s recommendation. Our previous survey of obstetricians and gynecologists in Japan regarding their opinions toward HPV vaccination revealed that these key specialists were as negatively influenced by the reports of purported negative events as were the general population. Here, we report a 3-year follow-up survey of these clinicians.

Methods

We reused the same questionnaire format as used in our 2014 survey, but added new questions concerning opinions regarding a WHO statement and reports of a Japanese nation-wide epidemiological study related to the adverse events, released in 2015 and 2016, respectively.

Results

The response rate was 46% (259/567): 5 (16.1%) of 31 doctors had inoculated their own teenaged daughters during the time period since the previous survey, despite the continued suspension of the governmental recommendation, whereas in the previous survey none of the doctors had done so. Among the respondents, the majority claimed awareness of the recent pro-vaccine WHO statement (66.5%), and of the report of a Japanese epidemiological study (71.5%), and a majority affirmed they currently held positive opinions of the safety (72.7%) and effectiveness (84.3%) of the HPV vaccine.

Conclusions

Our re-survey of Japan’s obstetricians and gynecologists regarding their opinions about the HPV vaccine found that their opinions have changed, potentially leading to a more positive future re-engagement for HPV vaccination in Japan.