Effectiveness of cervical cancer screening over cervical cancer mortality among Japanese women

Effect of screening mammography on the risk of breast cancer deaths and of all-cause deaths: a systematic review with meta-analysis of cohort studies

OBJECTIVES

Observational cohort studies are used to evaluate the effectiveness of screening mammography in women offered screening. Because screening mammography has no effect on causes of death other than breast cancer (BC), cohort studies should show reductions in the risk of BC death substantially greater than possible reductions in the risk of all-cause death. We assessed the risk of BC deaths and of all-cause (or of nonBC) deaths associated with screening mammography attendance reported in cohort studies.

STUDY DESIGN AND SETTING

Cohort studies published from 2002 to 2022 on women invited to screening mammography were searched in PubMed, Web of Sciences, Scopus, and in review articles. Random effect meta-analyses were performed using relative risks (RRs) of death between women who attended screening compared to women who did not attend screening.

RESULTS

Eighteen cohort studies were identified, nine that reported RRs of BC deaths only, five that reported RRs of all-cause deaths only, and four that reported RRs for both BC deaths and all-cause deaths. The latter four cohort studies reported 12-76 times more all-cause deaths than BC deaths. The random-effect summary of RR for BC mortality in screening attendees vs nonattendees was 0.55 (95% CI: 0.50-0.60) in 13 cohort studies. The summary of RR for all-cause mortality was 0.54 (0.50-0.58) in 10 cohort studies. In the four cohort studies that evaluated both outcomes, the summary of RRs were 0.63 (0.43-0.83) for BC mortality and of 0.54 (0.44-0.64) for all-cause mortality.

CONCLUSION

The similar relative reductions in breast- and all-cause (or nonBC) mortality indicates that screening mammography attendance is an indicator of characteristics associated with a lower risk of dying from any cause, including from BC, which observational studies have falsely interpreted as a screening effect.

Concurrent participation in breast, cervical, and colorectal cancer screening programmes in Denmark: A nationwide registry-based study

Women in Denmark are invited to breast, cervical, and colorectal cancer screening in their fifties and sixties. We determined the patterns of concurrent participation in the three programmes. Participation in organised cancer screening was determined using the highly complete Danish population and health care registers for all women aged 53-65 years on 31 March 2018 who continuously resided in Denmark since 1 April 2012. Data were linked using unique personal identification numbers. We studied overall and cancer-specific proportions of women undergoing screening for all three, two, one, and none of the cancers. Among all 468,507 women, 406,306 (87%) participated in breast, 345,768 (74%) in cervical, and 316,496 (68%) in colorectal cancer screening. Despite high participation, only 255,698 (55%) women were screened for all three cancers, while 123,469 (26%) were screened for two, 54,538 (12%) for one, and 34,802 (7%) were not screened for any cancer. Cancer-specific patterns were highly heterogeneous across the population but changed little after accounting for women's medical history. A significant proportion of women who are screened for a specific cancer remain unscreened for other cancers. The consistency of these data at the international level requires a reconsideration of invitational practices for organised screening.

Effect of Pap smears on the long-term survival of cervical cancer patients: a nationwide population-based cohort study in Korea

OBJECTIVES

This study aimed to investigate the effect of cervical cancer screening by Papanicolaou (Pap) smears on the long-term survival of cervical cancer patients.

METHODS

We constructed a retrospective cohort of 14,903 women diagnosed with invasive cancer or carcinoma in situ in 2008 and 2009 and followed up until December 31, 2019, by using individual-level data from 3 national databases of the Korean National Cancer Screening Program, the Korean Central Cancer Registry, and death certificates. Cox proportional-hazards regression was used to investigate the effect of cervical cancer screening on mortality.

RESULTS

In total, 12,987 out of 14,867 patients (87.4%) were alive at the end of the follow-up period (median: 10.5 years). Screened patients had a 38% lower risk of cervical cancer death than never-screened patients (hazard ratio [HR], 0.62; 95% confidence interval [CI], 0.54 to 0.70). Screening was associated with 59% and 35% lower risks of death, respectively, in screened patients with localized and regional stages. Furthermore, lower HRs among women who received screening were observed in all age groups, especially women aged 50-59 years (HR, 0.54; 95% CI, 0.42 to 0.69). The lowest HR for cervical cancer death was reported among patients screened within the past 2 years (HR, 0.54; 95% CI, 0.47 to 0.63), and the HRs increased with increasing time intervals.

CONCLUSIONS

Pap smear screening significantly reduced the risk of cervical cancer-specific death in Korean women across all cancer stages.

Novel Antigenic Targets of HPV Therapeutic Vaccines

Human papillomavirus (HPV) infection is the cause of the majority of cervical cancers and head and neck cancers worldwide. Although prophylactic vaccines and cervical cancer screening programs have shown efficacy in preventing HPV-associated cervical cancer, cervical cancer is still a major cause of morbidity and mortality, especially in third world countries. Furthermore, head and neck cancer cases caused by HPV infection and associated mortality are increasing. The need for better therapy is clear, and therapeutic vaccination generating cytotoxic T cells against HPV proteins is a promising strategy. This review covers the current scene of HPV therapeutic vaccines in clinical development and discusses relevant considerations for the design of future HPV therapeutic vaccines and clinical trials, such as HPV protein expression patterns, immunogenicity, and exhaustion in relation to the different stages and types of HPV-associated lesions and cancers. Ultimately, while the majority of the HPV therapeutic vaccines currently in clinical testing target the two HPV oncoproteins E6 and E7, we suggest that there is a need to include more HPV antigens in future HPV therapeutic vaccines to increase efficacy and find that especially E1 and E2 could be promising novel targets.

The association between cervical cancer screening participation and the deprivation index of the location of the family doctor's office

Background

Cervical cancer screening rates are known to be strongly associated with socioeconomic status. Our objective was to assess whether the rate is also associated with an aggregated deprivation marker, defined by the location of family doctors’ offices.

Methods

To access this association, we 1) collected data from the claim database of the French Health Insurance Fund about the registered family doctors and their enlisted female patients eligible for cervical screening; 2) carried out a telephone survey with all registered doctors to establish if they were carrying out Pap-smears in their practices; 3) geotracked all the doctors’ offices in the smallest existing blocks of socioeconomic homogenous populations (IRIS census units) that were assigned a census derived marker of deprivation, the European Deprivation Index (EDI), and a binary variable of urbanization; and 4) we used a multivariable linear mixed model with IRIS as a random effect.

Results

Of 348 eligible doctors, 343 responded to the telephone survey (98.6%) and were included in the analysis, encompassing 88,152 female enlisted patients aged 25–65 years old. In the multivariable analysis (adjusted by the gender of the family doctor, the practice of Pap-smears by the doctor and the urbanization of the office location), the EDI of the doctor’s office was strongly associated with the cervical cancer screening participation rate of eligible patients (p<0.001).

Conclusion

The EDI linked to the location of the family doctor’s office seems to be a robust marker to predict female patients’ participation in cervical cancer screening.

Concurrent participation in screening for cervical, breast, and bowel cancer in England

Objectives

To determine how many women participate in all three recommended cancer screening programmes (breast, cervical, and bowel). During their early 60s, English women receive an invitation from all the three programmes.

Methods

For 3060 women aged 60–65 included in an England-wide breast screening case–control study, we investigated the number of screening programmes they participated in during the last invitation round. Additionally, using the Fingertips database curated by Public Health England, we explored area-level correlations between participation in the three cancer screening programmes and various population characteristics for all 7014 English general practices with complete data.

Results

Of the 3060 women, 1086 (35%) participated in all three programmes, 1142 (37%) in two, 526 (17%) in one, and 306 (10%) in none. Participation in all three did not appear to be a random event (p < 0.001). General practices from areas with less deprivation, with more patients who are carers or have chronic illnesses themselves, and with more patients satisfied with the provided service were significantly more likely to attain high coverage rates in all programmes.

Conclusions

Only a minority of English women is concurrently protected through all recommended cancer screening programmes. Future studies should consider why most women participate in some but not all recommended screening.

How asymptomatic are early cancer patients of five organs based on registry data in Japan

BACKGROUND

One reason for the low cancer screening rate in Japan is that people are not concerned about cancer if they do not have symptoms.

METHODS

The authors retrospectively analyzed 18,405 cancer patients using hospital-based cancer registry data collected between 2007 and 2013 at the 13 hospitals of Shimane Prefecture, Japan. The symptomatic rates of five cancers (stomach, colorectal, lung, breast, and cervix) at each stage and the time of early diagnosis were investigated. The early detection rates of symptomatic and asymptomatic individuals were investigated.

RESULTS

The percentages of symptomatic cases tended to increase with progressive stages. The odds ratio (OR) of stage IV compared with that of stage I was 12.23 for stomach, 7.21 for colorectal, 16.91 for lung, 10.30 for breast, and 51.62 for cervical cancer. The proportions of early symptomatic cases at the time of diagnosis were low. Compared with the percentage of early symptomatic cases of stomach cancer of 25.5%, the percentage of lung cancer was the lowest, at 8.2% (OR 0.26), and the percentage of breast cancer was the highest, at 30.2% (OR 1.26). The percentages of early symptomatic cases of colorectal and cervical cancer were 18.9% (OR 0.68) and 19.9% (OR 0.73), respectively. The early detection rates of the asymptomatic and symptomatic groups were 77.6 and 36.1%, respectively.

CONCLUSION

Cancer registry data indicate that early cancers are asymptomatic, and once symptoms appear, treatment may not be effective. Policy makers should inform people of the necessity of cancer screening before they have symptoms.

Trends and Age-Period-Cohort Effects on the Incidence and Mortality Rate of Cervical Cancer in Korea

PURPOSE

This study was conducted to describe the trends and age-period-cohort effects on the incidence and mortality rate of cervical cancer in Korea.

MATERIALS AND METHODS

The incidence and mortality rate of cervical cancer among ≥ 20-year-old women from 1993 to 2012 were obtained from the Korea Central Cancer Registry and the Korean Statistical Information Service. Age-standardized rates were calculated and Joinpoint regression was used to evaluate the trends in the incidence and mortality rate. Age-period-cohort analysis was performed to investigate the independent effects of age, period and cohort.

RESULTS

The incidence of cervical cancer decreased from 32.8 per 100,000 in 1993 to 15.9 per 100,000 in 2012 (annual percent change [APC], -3.9%; 95% confidence interval [CI], -4.2% to -3.6%). The mortality rate decreased from 5.2 per 100,000 in 1993 to 2.1 per 100,000 in 2012 (APC, -4.8%; 95% CI, -5.1% to -4.4%); however, the incidence and mortality rates among young women (< 30 years old) increased. An age-period-cohort model of the incidence and mortality rate showed decreasing period effects between 1993 and 2008 and decreasing cohort effects between 1928 and 1973, while birth cohorts after 1973 exhibited slight increases in the incidence and mortality rate of cervical cancer.

CONCLUSION

Recent decreases in the incidence and mortality rate of cervical cancer were due to decreases in the period and cohort effects, which reflect the implementation of a cancer screening program and changes in lifestyle. However, our findings also highlighted an increase in cohort effects on the incidence and mortality rate among young women born after 1973.

Psychological impact of positive cervical cancer screening results among Japanese women

BACKGROUND

While cervical cancer screening is useful for detecting and then treating the disease at an early stage, most women with screen-positive results are free from cervical cancer but nevertheless subject to the unnecessary worry entailed in receiving such results. The purpose of this study was to examine whether receiving a screen-positive result was actually related to psychological distress among Japanese women who underwent cervical cancer screening.

METHODS

We conducted a questionnaire survey at health facilities in a semiurban city of Ibaraki prefecture, involving 1744 women who underwent cervical cancer screening and 72 who received screen-positive results and then underwent further testing. We used the K6 scale to assess their psychological distress (K6 score ≥5) and performed multiple logistic regression analyses to estimate the relative effect of receiving screen-positive results on psychological distress.

RESULTS

Psychological distress was more prevalent among women with screen-positive results (OR 2.22; 95 % CI 1.32-3.74), while it was also related to history of mental health consultation (OR 2.26; 95 % CI 1.69-3.01) and marital status (OR 1.32; 95 % CI 1.02-1.70).

CONCLUSIONS

Receiving a positive cervical cancer screening result was associated with psychological distress. To alleviate this psychological impact, the current form of communicating the screening results should be reconsidered.

Predictive value of p16/Ki-67 immunocytochemistry for triage of women with abnormal Papanicolaou test in cervical cancer screening: a systematic review and meta-analysis

BACKGROUND

The Papanicolaou (Pap) test is one screening strategy used to prevent cervical cancer in developed countries. The p16/Ki-67 immunocytochemistry is a triage test performed on Pap smears in women with atypical squamous cells of undetermined significance (ASCUS) or low grade squamous intraepithelial lesion.

OBJECTIVE

Our objective was to review studies investigating the diagnostic performance of p16/Ki-67 dual stain for triage of women with abnormal Pap tests.

DESIGN

We conducted a systematic review and meta-analysis of diagnostic test accuracy studies.

SETTINGS

We followed the protocol of systematic review of diagnostic accuracy studies.

PATIENTS AND METHODS

We searched PubMed, The Cochrane Library, BioMed Central, and ClinicalTrials.gov for relevant studies. We included research that assessed the accuracy of p16/Ki-67 dual stain and high risk human papillomavirus testing for triage of abnormal Pap smears. Review articles and studies that provided insufficient data to construct 2.2 tables were excluded. Data synthesis was conducted using a random-effects model.

MAIN OUTCOME MEASURES

Sensitivity and specificity.

RESULTS

In seven studies encompassing 2628 patients, the pooled sensitivity and specificity of p16/Ki-67 for triage of abnormal Pap smear results were 0.91 (95% CI, 0.89 to 0.93) and 0.64 (95% CI, 0.62 to 0.66), respectively. No study used a case-control design. A subgroup analysis involving liquid-based cytology showed a sensitivity of 0.91 (95%CI, 0.89 to 0.93) and specificity of 0.64 (95%CI, 0.61 to 0.66).

CONCLUSIONS

Our meta-analysis of p16/Ki-67 dual stain studies showed that the test achieved high sensitivity and moderate specificity for p16/Ki-67 immunocytochemistry for high-grade squamous intraepi.thelial lesion and cervical cancer. We suggest that p16/Ki-67 dual stain might be a reliable ancillary method identifying high-grade squamous intraepithelial lesions in women with abnormal Pap tests.

LIMITATIONS

No study in the meta-analysis examined the accuracy of the p16/Ki-67 dual stain for inter.pretation of glandular neoplasms.

Trends in cervical cancer screening in developing countries

Developing countries suffer the highest burden of cervical cancers but have the lowest resources. Effective cervical cytology screening programme, along with a network of diagnostic and therapeutic colposcopy centres, like developed countries, is almost impossible to be reproduced in developing countries. Visual inspection methods [e.g., Visual inspection with Lugol’s iodine (VILI) and Visual Inspection with Acetic Acid (VIA)] which are cheaper, require less expertise and have the advantage of possible treatment in one setting have been shown to be effective alternatives. The sensitivity to detect CIN2+, by VIA and VILI, have been shown to be 80% and 91% respectively, with a specificity rate of 92% and 85% respectively. Screening by human papillomavirus (HPV) testing has high sensitivity (96.4%) but low specificity (94.1%) to detect CIN2+, when compared to Pap Smear (sensitivity, 55.4% and specificity, 96.8%). A single lifetime HPV testing in a large unscreened population has been shown to significantly reduce cervical cancer incidence and mortality when compared to cervical cytology, VIA or no screening. HPV testing of self-collected vaginal specimens also helps to overcome religious and socio-cultural barriers towards pelvic examination amongst women in developing countries. Current HPV testing methods are expensive, skill/infrastructure demanding and takes time to produce results. A cheaper HPV test, called careHPV™, which is able to provide results within 2.5 h and requires minimal skill/infrastructure to operate, was designed for use in developing countries. One stop screen and treat facilities using VIA or rapid HPV testing, and cryotherapy, can overcome non-compliance to follow-up which is a major issue in developing countries. Cure rates of 81.4% for CIN1, 71.4% for CIN2 and 68.0% for CIN3 at 6 mo after treatment have been reported. Incorporating telemedicine with cervicography of VIA or VILI or even telecolposcopy, has great potential in cervical cancer screening, especially in countries with vast geographical areas.

Performance of papanicolaou testing and detection of cervical carcinoma in situ in participants of organized cervical cancer screening in South Korea

Background

The present study measured the performance of the Papanicolaou (Pap) test and detection of cervical carcinoma in situ (CIS) and cancer in participants of organized cervical cancer screening in South Korea, and examined differences in the proportion of CIS according to socio-demographic factors.

Methods

Data were obtained from the National Cancer Screening Program and National Health Insurance Cancer Screening Program databases. We analyzed data from 4,072,997 screenings of women aged 30 years or older who underwent cervical cancer screening by Pap test between January 1, 2005 and December 31, 2006. We calculated the performances of the Pap test and compared that according to socio-demographic factors.

Results

The positivity rate for all screenings was 6.6%. The cancer detection rate (CDR) and interval cancer rate (ICR) were 0.32 per 1,000 screenings, and 0.13 per 1,000 negative screenings, respectively. About 63.4% of screen-detected CIS+ cases (CIS or invasive cervical cancer) were CIS. The CDR and ICR, and percentage of CIS among all CIS+ were significantly different by age group and health insurance status. The odds ratios of CDR and ICR were higher for Medical Aid Program (MAP) recipients compared with National Health Insurance (NHI) beneficiaries. The likelihood of a detected CIS+ case to be CIS was significantly lower among MAP recipients than among NHI beneficiaries.

Conclusions

The difference in performance of cervical cancer screening among different socio-demographic groups may indicate an important influence of socio-demographic factors on preventive behavior. The findings of the study support the critical need for increasing efforts to raise awareness and provide more screening in at-risk populations, specifically low-income groups.

Current status of the National Cancer Screening Program for cervical cancer in Korea, 2009

Objective

The National Cancer Screening Program (NCSP) began in 1999. In this report, we evaluate the results of the NCSP for cervical cancer in 2009 and provide participation rates in an organized cervical cancer screening program in Korea.

Methods

Using data obtained from the National Cancer Screening Information System, cervical cancer screening participation rates were calculated. Recall rates, defined as the proportion of abnormal cases among women screened, were also estimated with 95% confidence intervals.

Results

The target population of cervical cancer screening in 2009 included 4,577,200 Korean women aged 30 and over, 1,349,668 of whom underwent the Papanicolaou smear test (29.5% participation rate). Compared with the participation rate of women covered by the National Health Insurance Program (31.3%), the participation rate of women covered by the Medical Aid Program was lower (18.4%). Participation rates also varied in different age groups (the highest of 39.3% in women aged 50 to 59 and the lowest of 14.4% in those aged 70 and older), and different areas (the highest of 34.1% in Busan and the lowest of 21.5% in Chungnam). The overall recall rate for cervical cancer screening was 0.41% (95% confidence interval, 0.40 to 0.42).

Conclusion

According to our study, efforts to facilitate participation and reduce disparities in cervical cancer screening among Korean women are needed.

The relation between the cancer screening rate and the cancer mortality rate in Japan

The aim of this research was to clarify the relation between the screening rates for five cancers (lung cancer, stomach cancer, colorectal cancer, uterus cancer, and breast cancer) and their mortality rate by using publicly accessible databases. The used information materials were those prepared by the Ministry of Health, Labour and Welfare, the Center for Cancer Control and Information Services, and the National Cancer Center. Our results were as follows: 1) regarding stomach and colorectal cancers, a positive correlation was found between the screening rate and the mortality rate (p<0.001); 2) in the relation between the screening rate and the mortality rate according to administrative divisions, the mortality rate decreased significantly when the lung cancer screening rate improved (p<0.005); 3) the mortality rate for breast cancer increased in those aged 50 or over; 4) the mortality rate for uterus cancer had been slightly increasing since 1990; and 5) regarding the screening rate, a positive correlation was found between breast cancer and uterus cancer (p<0.001). In future, improvement in lifestyle and in the knowledge of cancer should be promoted to enhance the screening rates.

Effectiveness of an organized cervical cancer screening program in Korea: results from a cohort study

Although the value of cervical cancer screening is widely acknowledged, the effectiveness of an organized cervical cancer screening program in Korea has never been evaluated. We investigated the associations of the frequency of cervical cancer screening with cervical cancer incidence using data from a large prospective cohort study. In this analysis, 253,472 women without a hysterectomy or previous cancer diagnosis were included. Follow-up was between 1995 and 2002. Frequency of Pap smear testing was determined by searching the National Health Examination Database. Using the Korean Central Cancer Registry, 248 cases of invasive cervical cancer and 346 cases of carcinoma in situ (CIS) of the cervix were identified. Subjects screened 2 or more times showed a 71% (corrected reduction 60%) and a 66% (corrected reduction 53%) reduced risk of invasive cervical cancer and CIS of the cervix, respectively, as compared with unscreened subjects [relative risk (RR) = 0.29; 95% confidence interval (CI) = 0.20-0.45; RR = 0.34; 95% CI = 0.25-0.46, respectively]. Women with a normal or benign pap smear had a statistically significantly lower risk of invasive cervical cancer and CIS of cervix compared with those never screened. In age-stratified analyses, there was a significant reduction in cervical cancer incidence among women aged 30 and over who were screened 2 or more times compared with women never screened. The results of this prospective cohort study show that regular screening of cervical cancer reduces invasive cervical cancer incidence and CIS of the cervix among Korean women.