Discrepancy between Cytology and Histology in Cervical Cancer Screening: a Multicenter Retrospective Study (KGOG 1040)

A Comparative Study of Conventional Pap Smear and Liquid-Based Cytology

Background

Cervical cancer is a major health issue globally, particularly in developing countries where it remains a leading cause of cancer-related deaths among women. In Georgia, it ranks as the fifth most frequent cancer among women overall and the third among women aged 15-44 years. Approximately 1.60 million women aged 15 years and older in Georgia are at risk of developing cervical cancer. Annually, about 327 women are diagnosed, and 204 die from the disease. Screening for cervical cancer is crucial for reducing incidence and mortality rates. While the conventional Pap smear has been the primary screening method, its limitations in sensitivity and sample adequacy have led to the development of liquid-based cytology (LBC).

Materials and Methods

This study analyzed 1000 cervical cytology samples from women aged 18-65 years in Georgia, who were gynecologically asymptomatic and not vaccinated for HPV. The median age was 37 years. Informed consent was obtained for all participants. Samples were collected using ThinPrep reagents (Hologic) and processed within 2 h. Smears were prepared using the ThinPrep 2000 Processor, fixed in absolute alcohol for 30 min, and stained according to the Papanicolaou protocol. The Bethesda 2001 System terminology was used for reporting. Smears were evaluated by light microscopy and archived per Georgian medical data requirements.

Results

The study found significant differences between the two screening methods. LBC showed a higher rate of satisfactory smears and better detection rates for negative for intraepithelial lesion or malignancy-NILM (89.4% vs. 80.3% for conventional Pap smear). Unsatisfactory smears were significantly lower with LBC (1.33% vs. 7.33%). Detection rates for atypical squamous cells of undetermined significance (ASCUS), atypical squamous cells, cannot exclude high grade squamous intraepithelial lesion (ASC-H), low grade squamous intraepithelial lesion (LSIL), and high grade squamous intraepithelial lesion (HSIL) were also improved with LBC, indicating higher diagnostic accuracy.

Conclusion

LBC outperforms the conventional Pap smear in cervical cancer screening by providing higher sample adequacy, better detection rates, and greater diagnostic accuracy. Implementing LBC more widely in Georgia could enhance early detection rates and reduce cervical cancer incidence and mortality, particularly in high-risk populations. These findings support the adoption of LBC as a superior screening method in clinical practice.

Significance and limitations of routine p16/Ki-67 immunohistochemistry as a diagnostic tool for high-grade squamous intraepithelial lesions of the uterine cervix

OBJECTIVE

To evaluate the diagnostic utility and limitations of routine p16 and Ki-67 immunohistochemistry (IHC) in detecting high-grade squamous intraepithelial lesions (HSILs) in the uterine cervix.

METHODS

We reviewed 2,061 cervical biopsy records, including 271 morphologically indeterminate squamous lesions, evaluated using p16/Ki-67 IHC for HSIL detection or exclusion. HSIL was diagnosed based on p16 positivity and a high Ki-67 labeling index (Ki-LI). In cases that remained inconclusive after IHC, follow-up histological and/or cytological outcomes were assessed.

RESULTS

p16/Ki-67 IHC established a definitive diagnosis of either HSIL or non-HSIL in 74.2% (201/271) of morphologically indeterminate cases, whereas 25.8% (70/271) remained inconclusive. p16/Ki-67 IHC contributed to diagnosing 120 HSIL cases, representing 11.9% (120/1,011) of all HSILs cases and 44.3% (120/271) of morphologically indeterminate cases. Among the 70 inconclusive cases, 58 had available follow-up data, of which 22 were subsequently diagnosed with HSIL, including 12 within 1 month of the initial biopsy. HSIL outcomes were more frequent in cases with suspicious HSIL on the initial biopsy (66.7% [12/18]). Based on the p16/Ki-LI status observed in the initial biopsy, patients with HSIL outcomes were categorized into three groups: p16-positive/low Ki-LI (54.2% [13/24]), p16-negative/high Ki-LI (50.0% [5/10]), and p16-negative/low Ki-LI (16.7% [4/24]). Multiple comparisons revealed a significant difference between the p16-positive/low Ki-LI and p16-negative/low Ki-LI groups (Benjamini-Yekutieli adjusted P=0.0435), while other comparisons were not significant.

CONCLUSION

p16/Ki-67 IHC significantly improved the diagnostic performance for HSIL. In cases that remain inconclusive after IHC, IHC-based risk stratification offers a valuable approach for surveillance, thus mitigating delays in HSIL diagnosis.

From the Beginning of the Korean Gynecologic Oncology Group to the Present and Next Steps

The Korean Gynecologic Oncology Group (KGOG) was established in 2002 and is the only organization in Korea conducting multi-center clinical trials for gynecologic cancers. Since its re-establishment as a non-profit organization in 2021, KGOG has grown significantly, now including 207 gynecologic oncology specialists from 76 hospitals. This growth is a testament to the dedication and hard work of all those involved in the organization. KGOG is committed to maximizing the activation of multi-center clinical research through policies that support patients with rare diseases and gynecologic cancer research, focusing on strengthening institutional capacity, equalizing participation opportunities, and enhancing information sharing. A significant milestone for KGOG was becoming a member of the US Gynecologic Oncology Group (GOG) in 2005, allowing participation in GOG clinical trials. KGOG later joined the Gynecologic Cancer InterGroup (GCIG) and strengthened its capabilities by hosting the first Endometrial Cancer Consensus Conference-Clinical Research (ECCC-CR) in 2023. KGOG holds biannual meetings and symposia, as well as 224 operating committee meetings annually to review the discussions of the Tumor Site Committee. KGOG has conducted 156 investigator-initiated trial (IIT) or sponsor-initiated trial (SIT) studies as KGOG-led or participated in research. Currently, 18 studies are registered, and 10 are in preparation. To date, 68 papers have been published. KGOG conducts six national projects and collaborates with external organizations such as the NRG Oncology Foundation, Gynecologic Oncology Group Partners (GOG-P), GCIG, East Asian Gynecologic Oncology Trial group (EAGOT), and the Japanese Gynecologic Oncology Group (JGOG). Through collaboration with renowned international research institutions, KGOG has significantly expanded the scope of its research, achieving noteworthy clinical outcomes. This report not only introduces the history and recent status of KGOG but also presents the exciting future direction of the organization, filled with potential breakthroughs and advancements in gynecologic oncology research.

Understanding the Dynamics of Human Papillomavirus and Diagnostic Discrepancies in Cervical Pathology: A Single Center Experience

Cervical cancer (CC) is the most prevalent gynecological malignancy and a leading cause of death among women. It is primarily caused by human papillomavirus (HPV) infection, with 99.7% of cases showing high-risk HPV genotypes. This study sheds light on HPV dynamics as well as the discrepancies of different CC screening modalities results while highlighting factors that may have contributed to such a scenario. Moreover, we underscore the importance of the non-viral etiology of CC as well. We examined the current trends of HPV infection and its effects on cervical health in women treated at a tertiary care center in Belgrade, Serbia. Patients with abnormal colposcopy findings like dysplasia and re-epithelization were more likely to test negative for HPV (p < 0.001). Interestingly, women with a positive Pap smear tested HPV negative significantly more often (p = 0.041). Finally, HPV-positive individuals were more likely to have CIN I and II histologies (p < 0.001), while CIN III occurred equally in women with and without the virus. It may be inferred that inconsistencies in detecting HPV and the presence of cervical lesions may eventually result in adjustments to screening guidelines, as is crucial to adopt a meticulous approach to promote periodical CC screening, as initial samples may test negative for HPV.

Cost-Effectiveness Analysis of HPV Extended versus Partial Genotyping for Cervical Cancer Screening in Singapore

Human papillomavirus (HPV) partial genotyping (PGT) identifies HPV16 and HPV18 individually, alongside 12 other high-risk HPV genotypes (hrHPV) collectively. HPV extended genotyping (XGT) identifies four additional hrHPV individually (HPV31, 45, 51, and 52), and reports the remaining eight in three groups (HPV33|58; 56|59|66; 35|39|68). Quality-adjusted life years (QALY), health care resource use, and costs of XGT were compared to PGT for cervical cancer screening in Singapore using DICE simulation. Women with one of the three hrHPV identified by XGT (HPV35|39|68; 56|59|66; 51), and atypical squamous cells of undetermined significance (ASCUS) on cytology, are recalled for a repeat screening in one year, instead of undergoing an immediate colposcopy with PGT. At the repeat screening, the colposcopy is performed only for persistent same-genotype infections in XGT, while with PGT, all the women with persistent HPV have a colposcopy. Screening 500,122 women, aged 30-69, with XGT, provided an incremental cost-effectiveness ratio (ICER) versus PGT of SGD 16,370/QALY, with 7130 (19.4%) fewer colposcopies, 6027 (7.0%) fewer cytology tests, 9787 (1.6%) fewer clinic consultations, yet 2446 (0.5%) more HPV tests. The XGT ICER remains well below SGD 100,000 in sensitivity analyses, (-SGD 17,736/QALY to SGD 50,474/QALY). XGT is cost-effective compared to PGT, utilizes fewer resources, and provides a risk-based approach as the primary cervical cancer screening method.

Non-Invasive Differential Diagnosis of Cervical Neoplastic Lesions by the Lipid Profile Analysis of Cervical Scrapings

Cervical cancer is one of the most common cancers in women with pronounced stages of precancerous lesions. Accurate differential diagnosis of such lesions is one of the primary challenges of medical specialists, which is vital to improving patient survival. The aim of this study was to develop and test an algorithm for the differential diagnosis of cervical lesions based on lipid levels in scrapings from the cervical epithelium and cervicovaginal canal. The lipid composition of the samples was analyzed by high-performance chromato-mass spectrometry. Lipid markers were selected using the Mann–Whitney test with a cutoff value of 0.05 and by projections to latent structures discriminant analysis, where a projection threshold of one was chosen. The final selection of variables for binomial logistic regressions was carried out using the Akaike information criterion. As a result, a final neoplasia classification method, based on 20 logistic regression sub-models, has an accuracy of 79% for discrimination NILM/cervicitis/LSIL/HSIL/cancer. The model has a sensitivity of 83% and a specificity of 88% for discrimination of several lesions (HSIL and cancer). This allows us to discuss the prospective viability of further validation of the developed non-invasive method of differential diagnosis.

Spectrum of Abnormal Cervical Lesions and its Cytohistological Correlation: a Study from an Institute of National Importance of Western Rajasthan

Objective: Cancer of the cervix is the second most common cancer in women worldwide. It accounts for 12% of all cancers in females. Our study aims to find out the pattern of cervical cytology on Papanicolaou smear (Pap smear) and its correlation with histopathological findings in the tertiary care referral centre of Western Rajasthan. Materials and methods: This is a prospective study carried out over two years, in which all cervical cytology smears were reported as per the 2014 Bethesda system and abnormal cytology was correlated with histopathological findings in cases where cervical biopsy or total hysterectomy specimens were available. Results:A total of 2291 cervical cytology smears were studied concerning age group, clinical signs and symptoms, and cytology findings. Cervical biopsy correlation was done in 65 patients aged 31-45 (45.61%) years. The mean age of our patients was 41 years. Among the 2291 smears, 181 were unsatisfactory for evaluation. In total, 1982 (86.51%) smears were negative for intraepithelial lesion and malignancy (NILM). Out of 61 abnormal smears, atypical squamous cells of undetermined significance (ASC-US) were seen in 26 (42.62%) cases, atypical squamous cells-cannot exclude high-grade squamous intraepithelial lesion (ASC-H) in nine (14.75%) cases, low-grade squamous intraepithelial lesion (LSIL) in four (6.56%) cases, while nine (14.75%) cases were positive for high-grade squamous intraepithelial lesion (HSIL). Invasive squamous cell carcinoma was seen in seven (11.48%) cases and two (3.28%) cases were positive for adenocarcinoma. Atypical glandular cells of undetermined significance (AGUS) were diagnosed in four (6.56%) cases. In our institutional study, specificity was 81.58% and sensitivity 83.33%. The cytohistopathological correlation was 68.18%, with HSIL (88.89%) having the highest correlation. Conclusion:Various new techniques have emerged in the diagnosis of a range of lesions of the cervix but as these technologies are costly, they cannot be implemented in poor set up countries. In the present scenario, the Pap smear test is considered the best screening method for cervical carcinoma. Biopsy is always considered to be the gold standard for carcinoma cervix provided that it is taken from representative areas.

Factors Associated with Cyto-Histological Misinterpretation of Cervical Smear according to Menopausal Status

OBJECTIVES

This study aimed to compare histological outcomes between pre-menopausal and post-menopausal women with cervical cytological abnormalities and to investigate the clinical factors affecting the misinterpretation of cytology and histology.

METHODS

We conducted a retrospective analysis of 599 patients with abnormal cervical cytology who underwent loop electrosurgical excision procedure (LEEP) between January 2010 and May 2019. Baseline characteristics were collected, including age, height, weight, body mass index, gravity, parity, and menopausal status. In total, 477 pre-menopausal women and 122 post-menopausal women were recruited.

RESULTS

Atypical squamous cells of undetermined significance (ASC-US) or low-grade squamous intraepithelial lesions were cytologically observed in 73.4% (135/184) of the pre-menopausal women, which were high-grade lesions confirmed by LEEP. In post-menopausal patients with cytology results that cannot exclude high-grade squamous intraepithelial lesions (ASC-H) or high-grade squamous intraepithelial lesions (HSIL), 27.0% (24/89) were confirmed to have histologically low-grade lesions. High-risk HPV (hrHPV) prevalence in abnormal cervical smears was 92.2%. Moreover, other hrHPVs had a higher risk of unexpected histological outcomes unrelated to cytologic results.

CONCLUSIONS

Menopausal status and HPV infection are associated with misinterpretation of cervical cytology and histology. Therefore, the menopausal status of patients should be considered for the management of cervical cytology, and primary co-testing is recommended to identify women at risk of cervical abnormalities.

Cervical Cytology–Histology Correlation Based on the American Society of Cytopathology Guideline (2017) at the Russian National Medical Research Center for Obstetrics, Gynecology, and Perinatology

Recent evidence suggests that a cytology–histology correlation (CHC) with discrepancy detection can both evaluate errors and improve the sensitivity and specificity of the cytologic method. We aimed to analyze the errors in cytologic–histologic discrepancies according to the CHC protocol guideline of the American Society of Cytopathology (2017). This retrospective study included 273 patients seen at the National Medical Research Center of Obstetrics, Gynecology and Perinatology (Moscow, Russia) between January 2019 and September 2021. The patients’ mean age was 34 ± 8.1 years. The cytology–histology agreement was noted in 158 cases (57.9%). Major discrepancies were found in 21 cases (7.6%), while minor discrepancies were noted in 93 cases (34.1%). The reason for 13 (4.8%) discrepancies was a colposcopy sampling error and, in 46 (16.8%) cases, the reason was a Papanicolaou (PAP) test sampling error. The discrepancy between primary and reviewed cytology was due interpretive errors in 13 (4.8%) cases and screening errors in 42 (15.4%) cases. We demonstrated that the ASC guidelines facilitate cervical CHC. A uniform application of these guidelines would standardize cervical CHCs internationally, provide a scope for the inter-laboratory comparison of data, and enhance self-learning and peer learning.