Meta-analysis on the performance of p16/Ki-67 dual immunostaining in detecting high-grade cervical intraepithelial neoplasm

Reevaluation of negative cervical conizations: Frequency, diagnostic errors, risk factors and management

OBJECTIVE

Cervical conization is an effective treatment for precancerous lesions. However, in cases where no high-grade lesion is identified in the surgical specimen, managing these patients may be challenging due to the absence of established follow-up protocols for negative conizations. This study aimed to assess the negative conization rates at our institution by histopathological review, identify diagnostic errors, possible risk and recurrence factors and propose follow-up strategies for this group of patients.

METHODS

A retrospective study from January-2010 to December-2020 analyzed patients with negative conization including all surgical techniques and procedure indications. Biopsy and cervical conizations slides were reviewed and patients who kept a negative result underwent deeper levels sectioning of the paraffin blocks with immunohistochemical stains application: p16, Ki-67 and geminin. Data were compared with a control group composed by 29 women with CIN3.

RESULTS

Out of 1022 conizations, 186 were negative (18.1%), with 151 cases selected for the study after excluding 35 patients. Following pathology review, 4 patients were excluded due to false-positive cervical biopsy results, 16 for false-negative conization results and 9 for hidden dysplasia identified after deeper sectioning. The remaining 122 patients were considered truly negative cones (11.9%) and exhibited IHC staining with p16 positive in 20.4% of cases, low Ki-67 expression, and low geminin score in most cases. Specimens with CIN 1 had higher prevalence of p16 staining, Ki-67 expression and geminin score when compared to absence of neoplasia, nevertheless geminin had no statistical difference. Older age, higher parity and IHC pattern with negative p16, low Ki-67 and geminin expressions were identified as risk factors for negative cones (p<0.05). Only 10 patients recurred for high-grade lesions, with no statistically significant risk factors identified.

CONCLUSIONS

The negative conization rate was 11.9%, with diagnostic errors identified across pre-surgical biopsy, cone specimen, and deeper levels. Risk factors included older age, higher parity, low expression of p16, Ki-67 and geminin (p<0.05). Recurrence represented 8.1% of the negative cones, without identification of statistically significant risk factors. Pathological review with deeper level sections and 2-year follow-up are recommended for patients with negative conizations.

Comparison of CINtec PLUS cytology and cobas HPV test for triaging Canadian patients with LSIL cytology referred to colposcopy: A two-year prospective study

OBJECTIVES & METHODS:

CINtec PLUS and cobas HPV tests were compared for triaging patients referred to colposcopy with a history of LSIL cytology in a 2-year prospective study. Cervical specimens were tested once at enrollment, and test positivity rates determined. Test performance was ascertained with cervical intraepithelial neoplasia grade 2 or worse (CIN2+) and CIN3 or worse (CIN3+) serving as clinical endpoints.

RESULTS:

In all ages, (19–76 years, n= 598), 44.3% tested CINtec PLUS positive vs. 55.4% HPV positive (p< 0.001). To detect CIN2+ (n= 99), CINtec PLUS was 81.8% sensitive vs. 93.9% for HPV testing (p= 0.009); genotype 16/18-specific sensitivity was 46.5%. Specificity was 52.9% vs. 36.6%, respectively (p< 0.001). In all ages, to detect CIN3+ (n= 44), sensitivity was 93.2% for both tests; genotype 16/18-specific sensitivity was 52.3%. Specificity was 48.4% for CINtec PLUS vs. 31.1% for HPV testing (p< 0.001). In patients < 30 years, CINtec was 91.7% sensitive vs 95.8% for HPV testing (p= 0.549).

CONCLUSIONS:

CINtec PLUS or cobas HPV test could serve as a predictor of CIN3+ with high sensitivity in patients referred to colposcopy with a history of LSIL regardless of age while significantly reducing the number of LSIL referral patients requiring further investigations and follow-up in colposcopy clinics.

Role of Cervical Cancer Biomarkers p16 and Ki67 in Abnormal Cervical Cytological Smear

Introduction

Cervical cancer is the most common cancer in India. Screening for cervical cancer helps in marked reduction of invasive cervical cancers. The low sensitivity of Papanicolaou cytology (Pap smear) and high-risk human papillomavirus (HR-HPV) in excluding high-grade intraepithelial lesion (ASC-H) leads to unnecessary referrals to colposcopy-guided biopsy. The combined cervical cytology screening and HR-HPV have its own limitations and still need further standardization. Using additional biomarkers like staining with p16 and Ki-67 might help in triaging abnormal pap smear.

Materials and Methods

A prospective, cross-sectional study was performed over a period of 16 months in the Department of Obstetrics and Gynaecology, in collaboration with Department of Pathology. Study was conducted to know the efficacy of immunostaining with p16/Ki-67 in predicting the presence of significant lesion in cases of mild cytological atypia. PAP smears (conventional and LBC) along with P16, Ki-67 and available biopsies were correlated.

Results

Liquid-based cytology (LBC) was done in 2134 cases, out of which 46 cases showed abnormal cytological findings such as [22 atypical squamous cells of undetermined significance (ASCUS), 3 low-grade squamous intraepithelial lesion (LSIL), 8 atypical squamous cells cannot exclude high-grade lesion (ASC-H), 6 high-grade squamous intraepithelial lesion (HSIL), 5 squamous cell carcinoma (SCC), 2 adenocarcinoma, 1 atypical glandular cells of undetermined significance (AGUS)]. Immunostaining with p16 and Ki-67 was performed on 38 cases of abnormal cytological smears. Out of 38 abnormal cytology cases, 28 cases had shown co-staining for both p16 and Ki-67, suggestive of true HPV infection of the cells. Of the 38 cases, 07/14 ASCUS, 06/06 HSIL, 07/08 ASC-H, 05/05 squamous cell carcinoma and 02/02 adenocarcinoma also showed dual positivity for p16 and Ki-67. One case of AGUS was diagnosed, but the smear was unsatisfactory for immunocytochemical evaluation and excluded from the study. Three cases of LSIL were also diagnosed on cytological evaluation, and 1 of them however showed positivity for p16 and Ki-67 on immunocytochemistry (ICC). In the ASC-US group, the sensitivity and specificity of the immunostaining in diagnosing CIN2 + lesions were 87.51%, and in LSIL group, the sensitivity and specificity of the immunostaining in diagnosing CIN2 + lesions were 100%. p16/Ki-67 positivity also increased with cytological severity which in turn corresponded with histological findings: it reached from 50% in ASC-US to 100% in both HSIL and SCC categories.

Conclusion

This immunostaining with p16 and Ki67 can be a useful method in the triaging of the ASC-US and the LSIL group as considering the high sensitivity and specificity values.

CINtec PLUS and cobas HPV testing for triaging Canadian women referred to colposcopy with a history of low-grade squamous intraepithelial lesion: Baseline findings

Objective and methods

CINtec PLUS and cobas HPV tests were assessed for triaging women referred to colposcopy with a history of LSIL cytology. Both tests were performed at baseline using ThinPrep cervical specimens and biopsy confirmed cervical intraepithelial neoplasia grade 2 or worse (CIN2+) served as the clinical endpoint.

Results

In all ages, (19–76 years, n = 600), 44.3% (266/600) tested CINtec PLUS positive vs. 55.2% (331/600) HPV positive (p = 0.000). Based on 224 having biopsies, sensitivity to detect CIN2+ (n = 54) was 81.5% (44/54) for CINtec PLUS vs. 94.4% (51/54) for HPV testing (p = 0.039); specificities were, 52.4% (89/170) vs. 44.1% (75/170), respectively (p = 0.129). In women ≥30 years (n = 386), 41.2% (159/386) tested CINtec PLUS positive vs. 50.8% (196/386) HPV positive (p = 0.008). Based on 135 having biopsies, sensitivity to detect CIN2+ (n = 24) was 95.8% (23/24) for both CINtec PLUS and HPV tests; specificities were, 55.0% (61/111) vs. 50.5% (56/111), respectively (p = 0.503).

Conclusions

For women referred to colposcopy with a history of LSIL cytology, CINtec PLUS or cobas HPV test could serve as a predictor of CIN2+ with high sensitivity, particularly in women ≥30 years. Either test can significantly reduce the number of women requiring further investigations and follow up in colposcopy clinics.

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CINtec PLUS or cobas HPV DNA test is suitable for triaging women referred to colposcopy with a history of LSIL cytology.

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Either test could serve as a predictor of CIN2+ with high sensitivity, particularly in women >30 years.

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Either test can significantly reduce the size of LSIL referral population requiring further colposcopy clinic visits.

Cervical intraepithelial neoplasia in women who had vaccination against HPV

OBJECTIVE

To investigate the characteristics of women developing cervical intraepithelial neoplasia who had had a vaccination against human papillomavirus (HPV).

METHODS

A retrospective cohort study was carried out of women diagnosed with moderate or severe cervical dysplasia (CIN2+) in four Italian centers between 2015 and 2017. All women included had had previous bivalent or quadrivalent vaccination against HPV.

RESULTS

The present study included 43 patients affected by CIN2+. The median age was 28 (range, 21-41) years. Ten (23.3%) patients did not have a diagnosis of specific HPV type(s) involved: high-risk HPV was detected in 7 (16.3%) women while HPV testing was negative in 3 (6.9%) women. Lesions related to HPV16 were found in two patients. HPV types covered by nonavalent vaccination were diagnosed in 27/33 (81.8%) women. HPV types not covered by nonavalent vaccination were diagnosed in 6 (18.2%) women. Co-infections are most commonly detected in women with HPVs other than those included in the nonavalent vaccination (P=0.024).

CONCLUSION

Cervical dysplasia occurring after HPV vaccination is a rare condition. Theoretically, nonavalent vaccination should improve protection against more than 80% of HPV-related lesions compared to other vaccines.