Trends in cervical cancer screening rates among Korean women: results of the Korean National Cancer Screening Survey, 2005–2020

HPV vaccination status and effectiveness in Korean women with HPV16/18 infection (2010-2021): a retrospective study

OBJECTIVE

To evaluate human papillomavirus (HPV) vaccine effectiveness in a cohort of Korean women infected with HPV.

METHODS

From 2010 to 2021, Korean women aged 20-60 years who diagnosed HPV-positive atypical squamous cells of undetermined significance or low-grade squamous intraepithelial lesion were recruited from 6 hospitals. HPV vaccine effectiveness was estimated by observing the differences in pathological and clinical information and experimental results-prevalence, viral load (VL), physical state (PS), and HPV16/18 infection duration-between the vaccinated and unvaccinated groups.

RESULTS

HPV16/18 prevalence declined from 18.5% to 11.8% as vaccination rates increased from 14.3% to 60.7% in the 1,757 registered cohort women. DNA analysis from 96 samples collected from the participants, indicated that HPV vaccination reduced HPV16 VL by 6 times and increased E2/E6 ratio for both HPV16 and HPV18 by 1.4 and 5 times, respectively. The HPV16 infection rate-lasting more than 18 months from 31.0% to 21.6%-and the HPV18 infection rate-lasting more than 12 and less than 24 months from 35.5% to 21.1%-were reduced by vaccination. We found VL and the infection duration to be directly proportional. Moreover, HPV vaccination reduced not only the VL to 1/4 in both the persistence and clearance groups but also the persistence rate from 90% (27/30) to 70.6% (12/17) in HPV16.

CONCLUSION

HPV vaccination reduced the prevalence and duration of infection and kept the PS in an episomal form for both HPV16 and HPV18. The tendency of persistence VL to be higher than clearance in the unvaccinated group implies that the vaccine's effect of reducing VL in HPV16 may lower the risk of progression to cervical cancer by shortening the infection duration.

Implementation rate and related factors of confirmatory tests following an abnormal Pap smear: a nationwide study from the National Health Insurance

OBJECTIVE

This study aims to investigate the implementation rate and influencing factors of confirmatory tests for women with abnormal cervical cytology results in the Korean nationwide cervical cancer screening program.

METHODS

The National Health Insurance Service (NHIS) database was utilized to identify all Korean women who have participated in the Korean nationwide cervical cancer screening program from January 2011 and December 2021 using the NHIS database. Multiple logistic regression analysis was performed to estimate the multivariate odds ratio and evaluate the patients' characteristics.

RESULTS

The rate of abnormal Papanicolaou (Pap) smears showed an initial increase from 2011 to 2015 and subsequently reached a plateau after 2016. When examining specific subcategories, cases of atypical squamous cells of undetermined significance (ASC-US) increased from 28,546 cases (1.1%) in 2011 to 62,850 cases (1.7%) in 2021. In contrast, cases of HSIL and SCC declined from 3,535 cases (0.14%) to 2,763 cases (0.07%) and from 383 cases (0.01%) to 179 cases (0.005%), respectively. Furthermore, the implementation rate of confirmatory tests for women with abnormal cytology increased from 8,865 cases (21.0%) in 2011 to 39,045 cases (51.2%) in 2021. Regarding the specific subcategory of ASC-US, the number of confirmatory tests exhibited a substantial increase from 4,101 cases (14.4%) in 2011 to 30,482 cases (48.5%) in 2021. For SCC, there was no significant change, with 216 cases (56.4%) in 2011 and 102 cases (57.0%) in 2021. The implementation rate of confirmatory tests was found to be significantly associated with results of abnormal Pap smear, age, and residence. Notably, economic status did not emerge as a significant factor affecting the likelihood of undergoing confirmatory tests.

CONCLUSIONS

The severity of abnormal Pap smear results is a reliable indicator of the probability of undergoing a confirmatory test. Additional endeavors are required to improve the implementation rate among women who have received abnormal Pap smear results.

Regularity of cervical cancer screening in Korea: analysis using national public data for 12 years

OBJECTIVE

To assess the frequency of regular uptake of national cervical cancer screening (CCS) program and identify associated factors among Korean women.

METHODS

This study is a fundamental investigation that employs openly accessible public data of Korea through secondary data analysis. A cohort of 4,663 women from the 2007-2012 Korean National Health and Nutrition Examination Survey, was followed up for up to 12 years (2007-2018) to obtain the frequency of national CCS. Compliance level with CCS was categorized, and an ordinal logistic regression model was employed to investigate the contributing factors.

RESULTS

The regular uptake of CCS in South Korea was low at 18.9%. The trend of regular screening showed significant association with various factors, including age (40-59 years), household income (100%-150% bracket), occupation (service workers), place of residence (small to medium sized cities), education level (middle school graduates), marital status (married), and possession of private insurance. Moreover, individuals with a history of non-cervical cancer or carcinoma in situ of the cervix, a family history of cervical cancer, or a higher frequency of general check-ups demonstrated a stronger adherence to regular CCS uptake.

CONCLUSION

Our findings revealed that regular participation in CCS in Korea was lower than anticipated, with factors such as socioeconomic status, personal history of gynecologic issue, and frequency of general health check-ups playing influential roles. However, further research, including an exploration of unexamined psychological barriers to screening, is necessary to gain a better understanding the reasons behind the reduced rates of regular CCS among Korean women.

Risk Factors and Prognosis of Stroke in Gynecologic Cancer Patients

Increased life expectancy and cancer prevalence rates expose patients to a higher risk of developing other comorbidities such as stroke. This study aimed to evaluate the risk factors for and prognosis of stroke in patients with gynecological cancers. A single-center retrospective cohort study was conducted on patients with cervical, endometrial, and epithelial ovarian cancers. Patients were classified into three groups based on the period of stroke onset: at least one year before cancer diagnosis, within one year before cancer diagnosis to six months after the last treatment date, and six months after the last treatment date. Among the 644 patients, stroke occurred in 54 (8.4%). In univariate analysis, stroke was significantly associated with overall survival. In contrast, in multivariate analysis, stroke was significantly associated with age and hypertension, but not with overall survival. Age, pulmonary thromboembolism/deep vein thrombosis, histological grade, and tumor stage were significantly associated with overall survival. Therefore, it is important to establish an appropriate examination and treatment plan for patients with gynecologic cancers using a multidisciplinary approach that incorporates the patient's age, medical condition, and tumor characteristics rather than excessively considering the adverse effects of stroke on cancer prognosis.

Prevention Strategies and Early Diagnosis of Cervical Cancer: Current State and Prospects

Cervical cancer ranks third among all new cancer cases and causes of cancer deaths in females. The paper provides an overview of cervical cancer prevention strategies employed in different regions, with incidence and mortality rates ranging from high to low. It assesses the effectiveness of approaches proposed by national healthcare systems by analysing data published in the National Library of Medicine (Pubmed) since 2018 featuring the following keywords: "cervical cancer prevention", "cervical cancer screening", "barriers to cervical cancer prevention", "premalignant cervical lesions" and "current strategies". WHO's 90-70-90 global strategy for cervical cancer prevention and early screening has proven effective in different countries in both mathematical models and clinical practice. The data analysis carried out within this study identified promising approaches to cervical cancer screening and prevention, which can further enhance the effectiveness of the existing WHO strategy and national healthcare systems. One such approach is the application of AI technologies for detecting precancerous cervical lesions and choosing treatment strategies. As such studies show, the use of AI can not only increase detection accuracy but also ease the burden on primary care.

Understanding of Cervical Screening Adoption among Female University Students Based on the Precaution Adoption Process Model and Health-Belief Model

This study aimed to identify the decisional stages for cervical screening and corresponding cognitive factors in female university students. A cross-sectional study was conducted among Korean female university students aged 20-29 years through an online survey. The main outcome was the decisional stage of cervical screening adoption using the precaution adoption process model. The stages were classified into pre-adoption (the unawareness, unengaged, and undecided stages), adoption (the decided to act and acting stages), and refusal (the decided not to act stage). The cognitive factors in each stage were analyzed using the key concepts of the health-belief model. Cervical screening was defined as a clinical Papanicolaou (Pap) smear performed by a physician in a clinic. The final analysis included 1024 students. Approximately 89.0%, 1.0%, and 10.2% were classified as the pre-adoption, refusal, and adoption stages, respectively. Compared to the pre-adoption stage group, the adoption stage group was more likely to be older and have higher self-efficacy and knowledge. Most participants belonged to the pre-adoption stage-those unaware of cervical screening. Furthermore, most had a low level of knowledge and perception of cervical cancer and its screening. Therefore, our study highlighted the need for education to increase awareness and knowledge of cervical screening in this population.

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.

The necessity of continuing cervical cancer screening of elderly Korean women aged 65 years or older

BACKGROUND

Although the incidence of cervical cancer has decreased since the 1980s in Korea, it remains high among the elderly women. This study evaluated the suitability of cervical cancer screening for elderly Korean women aged ≥65 years according to recommendations by the American Society of Cytopathology and American Society for Colposcopy and Cervical Pathology.

METHODS

We retrospectively reviewed the records of patients who underwent cervical cancer screening, followed by liquid-based Pap test, human papillomavirus (HPV) test, and colposcopic punch biopsy at two academic hospitals from May 2008 to May 2018. The participants were divided into two groups <65 and ≥65 years old. Logistic regression analysis was performed to evaluate the association between cytology tests, HPV tests and the occurrence of high-risk lesions, ≥cervical intraepithelial neoplasia2 (CIN2).

RESULTS

The mean patient age was 49.02 ± 15.437 (range 15-91) years. No patients aged <25 years showed atypical squamous cell-cannot exclude high grade (ASC-H), squamous cell carcinoma (SCC), or adenocarcinoma (ADC). The incidence of high-grade squamous intraepithelial lesion (HISL) (39.7%) and ≥CIN 3 (40.2%) was significantly higher in patients ≥65 years of age than in other age groups. However, patients ≥65 years showed increased HSIL and HPV negativity and ASC-H, HSIL, and HPV positivity in those with ≥CIN 2 (both p = .043).

CONCLUSION

Korean women aged ≥65 years should undergo cervical cancer screening. The relevance of HPV or Cytology test alone or co-test for screening should be evaluated in this population.