p16ink4a and HPV L1 Immunohistochemistry is Helpful for Estimating the Behavior of Low-grade Dysplastic Lesions of the Cervix Uteri

Molecular and Immunohistochemical Cognizance of HPV16 in Oral Leukoplakia, Oral Squamous Cell Carcinoma and Oropharyngeal Squamous Cell Carcinoma

Prior studies have established the carcinogenic role of HPV16 and also demonstrated its unique biological behavior in cervical and oropharyngeal squamous cell carcinoma (OPSCC) but its role in oral leukoplakia (OL) and oral squamous cell carcinoma (OSCC) is not well explored. Therefore, in the present study, we assessed HPV16 prevalence using PCR and Anti-HPV16 antibodies for the first time and correlated its biological behavior using p16^INK4a and Ki67 proliferation index (PI) in OL, OSCC, and OPSCC. This study included 63 subjects comprising of 25 OL, 26 OSCC, and 12 OPSCC cases. Exfoliated cells were collected and processed for PCR followed by immunohistochemistry with primary antibodies p16^INK4a, Anti-HPV16, and Ki67. The expressions were evaluated and statistical analysis included Chi-square and Spearman's test. Cumulatively 37% (OL-7%, OSCC-14% & OPSCC-16%) of cases showed positive PCR expression. PCR positivity was observed to be significantly higher (p 0.00) in OPSCC (9/12) than OSCC (9/26) and OL (5/25) cases. Overall immunohistochemical expression of p16^INK4a, Anti-HPV16, and Ki67 were significantly (p 0.02) higher in HPV16 (PCR) positive cases. HPV16 + OSCC cases showed higher grades of p16^INK4a and Ki67 expression. We have demonstrated a prevalence of HPV16 in OL, OSCC, and OPSCC through PCR, which may be concluded as a gold standard for the detection of HPV16 DNA.

Use of Cap Analysis Gene Expression to detect human papillomavirus promoter activity patterns at different disease stages

Transcription of human papillomavirus (HPV) genes proceeds unidirectionally from multiple promoters. Direct profiling of transcription start sites (TSSs) by Cap Analysis Gene Expression (CAGE) is a powerful strategy for examining individual HPV promoter activity. The objective of this study was to evaluate alterations of viral promoter activity during infection using CAGE technology. We used CAGE-based sequencing of 46 primary cervical samples, and quantitatively evaluated TSS patterns in the HPV transcriptome at a single-nucleotide resolution. TSS patterns were classified into two types: early promoter-dominant type (Type A) and late promoter-dominant type (Type B). The Type B pattern was more frequently found in CIN1 and CIN2 lesions than in CIN3 and cancer samples. We detected transcriptomes from multiple HPV types in five samples. Interestingly, in each sample, the TSS patterns of both HPV types were the same. The viral gene expression pattern was determined by the differentiation status of the epithelial cells, regardless of HPV type. We performed unbiased analyses of TSSs across the HPV genome in clinical samples. Visualising TSS pattern dynamics, including TSS shifts, provides new insights into how HPV infection status relates to disease state.

Human papillomavirus DNA, HPV L1 capsid protein and p16INK4a protein as markers to predict cervical lesion progression

OBJECTIVES

Cervical cancer is the most common malignant tumors in women leading to serious morbidity and mortality worldwide, especially among developing countries. A main cause of the disease is the high-risk human papillomavirus (HR-HPV) infection. HSIL usually progress to cervical cancer, and low-grade lesions, including LSIL and ASCUS, mostly turn to normal or benign lesions, but there are still a small number of patients who will progress to HSIL. Up to now there is no efficient biomarker clinically available to predict people with high risk to progress into HSIL. This study was conducted to evaluate the value of human papillomavirus (HPV) DNA, p16^INK4a protein, and HPV L1 capsid protein in predicting HSIL and minimizing unnecessary colposcopy treatments.

METHODS

1222 patients with HR-HPV infection or with abnormal Thinprep cytologic test (TCT) were chosen to conduct colposcopy in the cervical out-patient clinic of Shanghai First Maternity and Infant Hospital affiliated to Shanghai Tongji University from June 2014 to January 2017. TCT, cervical biopsy, HPV DNA and HPVL1 were performed on all patients. 110 patients were selected to detect p16^INK4a protein. Hybrid capture 2 (HC-2) was used to detect HPV DNA, and their subgroups using gene typing system. Immunohistochemical technology was used to detect HPV L1 and p16.

RESULTS

HPV DNA was positive in 1097 cases, with the positive rate of 89.7% (1097/1222). In particular, the positive expression rates of HPV DNA were 82.3, 95.7, 96.6 and 100% in Normal/CC, LSIL, HSIL and cervical cancer groups, respectively (p < 0.001). HPV L1 was negative in 781 cases with HR-HPV infection, and the overall negative rate is 71.1%. In patients with Normal/CC, LSIL and HSIL, the negative expression rates of HPV L1 were 91.3, 40 and 81.2%, respectively (p value < 0.001). In the 110 patients, HPV L1 was negative in 98.1% (53/54) of Normal/CC, 42.9% (12/28) of LSIL and 85.1% (23/27) of HSIL (p value = 0.0043). P16-positive rates in patients with Normal/CC, LSIL and HSIL were 33.3% (18/54), 75% (21/28) and 96.2% (26/27), respectively (p value < 0.001). 18 out of 28 cases express low positive (+) in LSIL, 25 out of 27 cases express strong positive (3+) in HSIL. Patients with L1(-) p16(+) including 18.5% (10/54) of normal/cervicitis, 60.7% (17/28) of LSIL and 85.1% (23/27) of HSIL (p value < 0.005). Furthermore, patients with L1(-) p16(1+) included 37% (10/27) of normal/cervicitis 59.3% (16/27) of LSIL and 3.7% (1/27) of HSIL; patients with L1(-) p16(2+) consisted of 0% of normal/cervicitis/LSIL and 100% (1/1) of HSIL; patients with L1(-) p16(3+) were composed of 0% of normal/cervicitis, 4.5% (1/22) of LSIL and 95.5% (21/22) of HSIL (p value < 0.005) (Table 6).

CONCLUSION

With the increase in the degree of the cervical lesions, the expression of HPV DNA and p16 is up-regulated while HPV L1 protein is down-regulated. HPV DNA, HPV L1 and p16 are useful markers for the prediction of HSIL. Combined detection of these three markers has important potential to predicting HSIL and minimizing unnecessary colposcope examination.

Potential influence of p16 immunohistochemical staining on the diagnosis of squamous cell lesions in cervical biopsy specimens: observation from cytologic-histologic correlation

BACKGROUND

The p16 immunohistochemical (IHC) marker has been used increasingly as an adjunct to morphologic assessment of cervical biopsies in which the differential diagnoses include high-grade squamous intraepithelial lesion (HSIL) and its mimics. The objective of this study was to assess the potential influence of p16 IHC staining on the evaluation of cervical biopsy as observed through cytologic-histologic correlation (CHC).

METHODS

Cervical biopsy samples that had cytologic diagnoses of either low-grade squamous intraepithelial lesion (LSIL) or HSIL and also had histologic follow-up were retrieved from the department database. CHC and the use of p16 IHC from 2 periods (group 1, 2008; group 2, 2014-2016) were compared and analyzed.

RESULTS

Histology on 452 samples from patients who had prior LSIL cytology in group 1 yielded 126 benign (27.9%), 272 LSIL (60.2%), and 54 HSIL (11.9%) diagnoses. By comparison, 491 samples from the patients in group 2 yielded 106 benign (21.6%), 277 LSIL (56.4%), and 108 HSIL (22.0%) diagnoses. The difference in CHC discrepancies between the 2 groups was significant (P = .0001), mainly because of the increased diagnosis of HSIL in group 2. Although p16 IHC was not applied to any sample from group 1, it was performed on 141 of 491 samples (28.7%) from group 2. Further follow-up of patients who had histologic HSIL revealed that residual HSIL was identified significantly more often in those who did not have p16 IHC applied in the preceding cervical biopsy than in those did (P = .0004). A similar comparison was performed between 113 patients from group 1 and 152 patients from group 2 who had a prior diagnosis of HSIL cytology, and the difference was statistically insignificant.

CONCLUSIONS

The use of p16 IHC on cervical biopsies in patients who had a prior cytologic diagnosis of LSIL may lead to greater detection and upgrading of HSIL, thereby compounding the discrepancy in CHC.

E2/E6 ratio and L1 immunoreactivity as biomarkers to determine HPV16-positive high-grade squamous intraepithelial lesions (CIN2 and 3) and cervical squamous cell carcinoma

Objective

Human papillomavirus (HPV) 16 is the most carcinogenic HPV genotype. We investigated if HPV16 L1 capsid protein and E2/E6 ratio, evaluated by cervical cytology, may be used as biomarkers of ≥cervical intraepithelial neoplasia (CIN) 2 lesions.

Methods

Cervical specimens were obtained from 226 patients with HPV16 single infection. Using cytology specimen, L1 capsid protein and E2/E6 ratio were detected and the results were compared with those of the conventional histologic analysis of cervical tissues (CIN1–3 and squamous cell carcinoma [SCC]) to evaluate the association.

Results

The L1 positivity of CIN2/3 was significantly lower than that of normal cervical tissue (p<0.001) and SCC demonstrated significantly lower L1 positivity than CIN1 (p<0.001). The mean E2/E6 ratios of specimens graded as SCC (0.356) and CIN2/3 (0.483) were significantly lower than those of specimens graded as CIN1 (0.786) and normal (0.793) (p<0.05). We observed that area under the receiver operating characteristic curve (AUC) for E2/E6 ratio (0.844; 95% confidence interval [CI]=0.793–0.895) was higher than that for L1 immunochemistry (0.636; 95% CI=0.562–0.711). A combination of E2/E6 ratio and L1 immunocytochemistry analyses showed the highest AUC (0.871; 95% CI=0.826–0.917) for the prediction of ≥CIN2 lesions.

Conclusion

To our knowledge, this is the first study to validate HPV L1 capsid protein expression and decreased HPV E2/E6 ratio as valuable predictive markers of ≥CIN2 cervical lesions. Cervical cytology may be analyzed longitudinally on an outpatient basis with noninvasive procedures as against invasive conventional histologic analysis.

Immunohistochemistry and Polymerase Chain Reaction for Detection Human Papilloma Virus in Warts: A Comparative Study

Background

Immunohistochemistry and polymerase chain reaction (PCR) are the most widely used methods for the detection of viruses. PCR is known to be a more sensitive and specific method than the immunohistochemical method at this time, but PCR has the disadvantages of high cost and skilled work to use widely. With the progress of technology, the immunohistochemical methods used in these days has come to be highly sensitive and actively used in the diagnostic fields.

Objective

To evaluate and compare the usefulness of immunohistochemistry and PCR for detection human papilloma virus (HPV) in wart lesions.

Methods

Nine biopsy samples of verruca vulgaris and 10 of condyloma accuminatum were examined. Immunohistochemical staining using monoclonal antibody to HPV L1 capsid protein and PCR were done for the samples. DNA sequencing of the PCR products and HPV genotyping were also done.

Results

HPV detection rate was 78.9% (88.9% in verruca vulgaris, 70.0% in condyloma accuminatum) on immunohistochemistry and 100.0% for PCR. HPV-6 genotype showed a lower positivity rate on immunohistochemistry (50.0%) as compared to that of the other HPV genotypes.

Conclusion

Immunohistochemistry for HPV L1 capsid protein showed comparable sensitivity for detection HPV. Considering the high cost and great effort needed for the PCR methods, we can use immunohistochemistry for HPV L1 capsid protein with the advantage of lower cost and simple methods for HPV detection.

Effect of Lower Anogenital Squamous Terminology Recommendations on the Use of p16 Immunohistochemistry and the Proportion of High-Grade Diagnoses in Cervical Biopsy Specimens

OBJECTIVES

The Lower Anogenital Squamous Terminology (LAST) group has recommended that cervical intraepithelial neoplasia (CIN) terminology be replaced by squamous intraepithelial lesion (SIL) terminology, with p16 immunohistochemistry used to separate lesions formerly diagnosed as CIN grade 2 into high-grade SILs (HSILs) and low-grade SILs. This study investigated the impact of these changes on the frequency of p16 testing and the diagnosis of high-grade lesions.

METHODS

Pathology reports for all cervical biopsy specimens in the 1 year before and after the introduction of LAST recommendations (July 2011 to June 2013) were examined.

RESULTS

Before and after the implementation of LAST, 365 (15.4%) of 2,376 cases were diagnosed as high grade (CIN 2/3) vs 486 (17.6%) of 2,761 cases diagnosed as HSILs (P = .0343), and p16 was performed 79 (3.3%) times vs 383 (13.9%) times (P < .0001).

CONCLUSIONS

Immunohistochemistry for p16 increased dramatically as a result of LAST recommendations, and high-grade diagnoses increased.

p16 staining has limited value in predicting the outcome of histological low-grade squamous intraepithelial lesions of the cervix

In order to evaluate the usefulness of p16 staining in predicting the outcome of histological low-grade squamous intraepithelial lesion/cervical intraepithelial neoplasia grade 1 (LSIL/CIN1) we prospectively recruited all the patients referred to colposcopy from 2003 to 2011 due to abnormal screening test results and diagnosed with LSIL/CIN1 at biopsy (n=507). All biopsies were stained for p16 and re-evaluated after three years by the same gynecological pathologist using the LAST criteria. Follow-up was conducted every 6 months and included a Pap test (liquid-based cytology), high-risk human papillomavirus testing (Hybrid Capture 2 test), and colposcopy. The mean follow-up was 28 months. An outcome diagnosis of HSIL was defined as a histological diagnosis of high-grade SIL/CIN (HSIL/CIN2-3). The diagnosis of LSIL/CIN1 was confirmed in 416 out of 507 biopsies (82%), whereas 58 (11%) were reclassified as negative and 33 (6%) as HSIL/CIN2-3. During follow-up, 86/507 women initially diagnosed with LSIL/CIN1 (17%) showed an outcome diagnosis of HSIL/CIN2-3, with the rate of HSIL final diagnosis of 3% (2/58) in the women with biopsies reclassified as negative, 17% (70/416) in the group with confirmed LSIL and 42% (14/33) in the women with biopsies reclassified as HSIL (P<0.001). p16 was positive in 245/507 patients (48%) and in 210/416 patients (50%) with confirmed LSIL/CIN1 at re-evaluation. Although positive p16 immunostaining was associated with risk of HSIL/CIN2-3 outcome in the multivariate analysis (Hazard ratio (HR) 1.9; 95% confidence interval (CI): 1.2-3.1; P=0.009) in the overall group of patients with LSIL/CIN1, this association was not verified in the subset of patients with confirmed LSIL/CIN1 after re-evaluation (HR: 1.6; 95% CI: 0.9-2.6; P=0.095). In conclusion, in LSIL/CIN1 lesions p16 should be limited to equivocal cases in which HSIL/CIN2 is included in the differential diagnosis since it has low value in clinical practice as a marker of progression of LSIL/CIN1.

HPV infection and p16 promoter methylation as predictors of ASC-US/LSIL progression

BACKGROUND

Although patients found to have atypical squamous cells of undetermined significance (ASC-US) and low-grade squamous intraepithelial lesions (LSILs) on Papanicolaou (Pap) testing are treated conservatively, 5.2% to 18.8% of them progress to high-grade squamous intraepithelial lesions (HSILs). The objective of the current study was to identify predictors of progression to HSIL and determine what percentage of ASC-US/LSIL cases harbor cervical intraepithelial neoplasia of grade 2 or higher.

METHODS

The current study included 381 consecutive cases with ASC-US/LSIL. After the exclusion of 87 cases because of a history of dysplasia or loss to follow-up, 165 cases with follow-up cytology were used to analyze predictive factors of progression to HSIL, and 129 cases that underwent immediate tissue biopsy were subjected to correlation analysis between cytology and histology. Disease regression was defined as a reversion to normal or benign cellular changes, disease persistence as maintenance at ASC-US/LSIL, and disease progression as progression to HSIL. Data regarding clinical parameters were obtained from medical records. Methylation-specific polymerase chain reaction was performed using cytology samples to evaluate methylation of the p16 promoter.

RESULTS

Of 165 cases, 131 (79.4%) regressed, 23 (13.9%) were persistent, and 11 cases (6.7%) progressed. Human papillomavirus infection was more common in women with disease progression than in those with disease regression or persistence (P = .033). Promoter methylation of p16 in the cytology sample was more common in cases that progressed (5 of 6 cases) than in cases that regressed (0 of 8 cases). Twenty-three of 129 cases (17.8%) were found to harbor cervical intraepithelial neoplasia of grade 2 or higher on immediate tissue biopsy.

CONCLUSIONS

Human papillomavirus infection and p16 promoter methylation might be valuable surrogate markers of disease progression from ASC-US/LSIL to HSIL.

Utility of Human Papillomavirus Capsid Protein L1 and p16 in the Assessment and Accurate Classification of Anal Squamous Intraepithelial Lesions

OBJECTIVES

Morphologic evaluation of anal dysplasia remains problematic, especially in cases with limited biopsy samples or obscuring inflammation. Studies in cervical neoplasia have shown that human papillomavirus (HPV) L1 capsid production is highest in low-grade squamous intraepithelial lesions (LSILs) and progressively decreases in high-grade squamous intraepithelial lesions (HSILs). The combined utility of HPV L1 and p16 expression in assessing anal squamous intraepithelial lesions (SILs) has never been analyzed and forms the basis of this study.

METHODS

In total, 145 anal lesions were reviewed and immunohistochemically stained for HPV L1 and p16. p16 expression was recorded as negative, patchy/focal, or diffuse. For analytical purposes, condylomas were evaluated separately from rest of the LSILs.

RESULTS

There were 34 (23%) condylomas, 64 (44%) LSILs, and 47 (32%) HSILs. HPV L1 was significantly associated with condylomas (68%) and LSILs (52%) compared with HSILs (9%; P < .0001). Diffuse p16 staining was present only in HSILs (P < .0001), whereas a patchy/focal p16 staining pattern was observed in both LSILs and condylomas.

CONCLUSIONS

HPV L1 and diffuse p16 expression is mutually exclusive in most anal SILs and helps separate LSIL and HSIL cases. Application of both HPV L1 and p16 can not only facilitate accurate grading but also contribute to risk assessment in anal neoplasia.

p16INK4a immunohistochemical and histopathologic study of Pap test cases interpreted as HSIL without CIN2-3 identification in subsequent cervical specimens

Tissue biopsy following a pap test diagnosis of high grade squamous intraepithelial lesion (HSIL) sometimes fails to confirm the presence of a corresponding high grade cervical intraepithelial lesion (CIN 2-3), leading to confusion as to how best to manage the patient. It has been shown that these patients are still at higher risk for future detection of CIN 2-3 even if the initial biopsy fails to detect it. It has also been shown that immunohistochemical staining for p16INK4a can be reliably used as a surrogate marker for infection with high risk human papillomavirus in cervical samples, and that it can be used to enhance detection of CIN2-3 in cases where suspicion is high. To evaluate the use of p16INK4a staining in cases of HSIL which were not confirmed on initial biopsy, two pathologists rereviewed Pap and hematoxylin and eosin preparations from all such cases seen within the preceding 3 years. Immunohistochemical study for p16INK4a was performed and graded on representative sections. The results were tabulated and analyzed. Of the identified 596 HSIL Pap cases, 82% had HSIL on initial cervical specimens. Table 1 shows the 56 cases included in the study with graded and stratified p16INK4a results. On review of the p16INK4a slides, only 2 cases could be upgraded to HSIL/CIN2-3 from the original diagnosis. p16INK4a 2-3+ was expressed more frequently in cases initially interpreted on Pap as low-grade cervical lesion as compared with benign (24 of 35 cases). In the younger than 24-yr-old group p16 2-3+ reactivity was more frequent in benign and low-grade cervical lesion/CIN1 groups (benign: 3 of 5 cases, and CIN1: 6 of 8), and p16 negative reactivity was not seen. p16INK4a was graded 0-1+ more frequently in specimens interpreted as benign in the older than 25 yr olds (10 of 16 cases). The study suggests some diagnostic benefit from the use of p16INK4a immunohistochemical study on cervical specimens from women with a HSIL Pap test without HSIL/CIN2-3 on original hematoxylin and eosin review.

HPV-related squamous neoplasia of the lower anogenital tract: an update and review of recent guidelines

Squamous cell carcinomas of the lower anogenital tract that are related to human papillomavirus (HPV) infection represent a significant disease burden worldwide. The diagnosis and management of their noninvasive precursors has been the subject of extensive study and debate over several decades, accompanied by an evolving understanding of HPV biology. Recent new consensus recommendations for the pathologic diagnosis of these precursor lesions were published in 2012, the result of the Lower Anogenital Squamous Terminology project cosponsored by the College of American Pathologists and the American Society for Colposcopy and Cervical Pathology. Most salient among the new guidelines are the recommendation to switch to a 2-tiered nomenclature (high-grade squamous intraepithelial lesion and low-grade squamous intraepithelial lesion) rather than the traditional 3-tiered "intraepithelial neoplasia" terminology, and the recommendation to expand use of the immunohistochemical marker p16 to distinguish between low-grade squamous intraepithelial lesion and high-grade squamous intraepithelial lesion/intraepithelial neoplasia 2. The goals of the project were to align diagnostic terminology with our knowledge of HPV biology, increase reproducibility, consolidate diverse systems of nomenclature, and ultimately better determine a patient's true cancer risk. The clinical guidelines for screening and management of cervical intraepithelial neoplasia have also been recently updated, most notably with a lengthening of screening intervals. In this review, we focus on the new guidelines put forth for pathologic diagnosis of HPV-related anogenital neoplasia, with discussion of the evidence behind them and their potential implications. We also provide an update on relevant biomarkers, clinical recommendations, and the newest developments relating to cervical neoplasia.

The clinical impact of using p16(INK4a) immunochemistry in cervical histopathology and cytology: an update of recent developments

Cervical cancer screening test performance has been hampered by either lack of sensitivity of Pap cytology or lack of specificity of Human Papillomavirus (HPV) testing. This uncertainty can lead to unnecessary referral and treatment, which is disturbing for patients and increases costs for health care providers. The identification of p16(INK4a) as a marker for neoplastic transformation of cervical squamous epithelial cells by HPVs allows the identification of HPV-transformed cells in histopathology or cytopathology specimens. Diagnostic studies have demonstrated that the use of p16(INK4a) immunohistochemistry substantially improves the reproducibility and diagnostic accuracy of histopathologic diagnoses. p16(INK4a) cytology has substantially higher sensitivity for detection of cervical precancer in comparison to conventional Pap tests. Compared to HPV DNA tests, immunochemical detection of p16(INK4a) -stained cells demonstrates a significantly improved specificity with remarkably good sensitivity. About 15 years after the initial observation that p16(INK4a) is overexpressed in HPV-transformed cells we review the accumulated clinical evidence suggesting that p16(INK4a) can serve as a useful biomarker in the routine diagnostic work up of patients with HPV infections and associated lesions of the female anogenital tract.

P16INK4A immunohistochemistry for detection of human papilloma virus-associated penile squamous cell carcinoma is superior to in-situ hybridization

We evaluated p16INK4A as a reliable option to detect human papilloma virus (HPV) DNA in penile tumor specimens. Formalin-fixed paraffin embedded samples of 26 patients with penile cancer and another 18 cases with non-tumorigenic lesions were stained by three different widely used commercially available chromogenic in-situ hybridization assays high-risk HPV CISH Y1443 (Genpoint, DAKO), pan HPV CISH Y1404 (Genpoint, DAKO), INFORM HPV III (Ventana, Tucson, Arizona) and p16INK4A immunohistochemistry, then compared to the known gold standard polymerase chain reaction detecting HPV 16, 18, 31, and 33. Immunoreactivity for p16INK4A was evaluated by using a 4-tiered (0, 1, 2, and 3) pattern based system. 19 cases were positive for p16INK4A, 13 of which showed a continuous transepithelial staining (pattern 3). Pan HPV ISH showed positivity in 9 cases, high-risk HPV ISH in 7 cases and INFORM HPVIII ISH in 7 cases. p16INK4A IHC pattern 3 versus pattern 0, 1 and 2 exhibited a specificity and positive predictive value of 100 percent, with a sensitivity and negative predictive value of 72 and 62 percent, respectively, which was much better than all HPV in-situ hybridization methods referred to polymerase chain reaction. p16INK4A seems to be a superior marker for the detection of HPV-associated penile squamous cell carcinoma compared to CISH tests, but is not recommend for the detection of non-tumorigenic lesions, where PCR should be used for the initial assessment.

Clinicopathological implications of human papilloma virus (HPV) L1 capsid protein immunoreactivity in HPV16-positive cervical cytology

BACKGROUND

The objective of this study was to investigate the expression of human papilloma virus (HPV) L1 capsid protein in abnormal cervical cytology with HPV16 infection and analyze its association with cervical histopathology in Korean women.

MATERIAL AND METHODS

We performed immunocytochemistry for HPV L1 in 475 abnormal cervical cytology samples from patients with HPV16 infections using the Cytoactiv(®) HPV L1 screening set. We investigated the expression of HPV L1 in cervical cytology samples and compared it with the results of histopathological examination of surgical specimens.

RESULTS

Of a total of 475 cases, 188 (39.6%) were immunocytochemically positive and 287 (60.4%) negative for HPV L1. The immunocytochemical expression rates of HPV L1 in atypical squamous cells of unknown significance (ASCUS), low-grade squamous intraepithelial lesions (LSIL), high-grade squamous intraepithelial lesions (HSIL), and cancer were 21.8%, 59.7%, 19.1%, and 0.0%, respectively. LSIL exhibited the highest rate of HPV L1 positivity. Of a total of 475 cases, the multiple-type HPV infection rate, including HPV16, in HPV L1-negative cytology samples was 27.5%, which was significantly higher than that in HPV L1-positive cytology samples (p = 0.037). The absence of HPV L1 expression in ASCUS and LSIL was significantly associated with high-grade (≥ cervical intraepithelial neoplasia [CIN] 2) than low-grade (≤ CIN1) histopathology diagnoses (p < 0.05), but was not significantly different between HPV16 single and multiple-type HPV infections (p > 0.05). On the other hand, among 188 HPV L1-positive cases, 30.6% of multiple-type HPV infections showed high-grade histopathology diagnoses (≥ CIN3), significantly higher than the percentage of HPV16 single infections (8.6%) (p = 0.0004) CONCLUSIONS: Our study demonstrates that the expression of HPV L1 is low in advanced dysplasia. Furthermore, the absence of HPV L1 in HPV16-positive low-grade cytology (i.e., ASCUS and LSIL) is strongly associated with high-grade histopathology diagnoses. The multiplicity of HPV infections may have an important role in high-grade histopathology diagnoses (≥ CIN3) in HPV L1-positive cases.

Immunohistochemical expression of p16 and HPV L1 capsid proteins as predictive markers in cervical lesions

PURPOSE

Human papilloma virus (HPV) infection is the most important cause of cervical cancer, but only 2 % of cervical HPV infections will develop into cervical cancer. p16 INK4A has been introduced as a marker for HPV infection in cervix. HPV L1 capsid protein is also known to be associated with the productive phase of HPV infection; however, expression pattern in different HPV-associated cervical lesion and its correlation to p16 expression is not still well understood. The authors aimed to elucidate the relationship between L1 and p16 expression in cervical lesions.

METHODS

Immunohistochemical studies using antibodies against L1 capsid and P16 proteins were carried out on 89 paraffin-embedded tissue samples including 11 low-grade cervical intraepithelial neoplasias (CIN), 11 high-grade CINs, 20 cervical squamous cell carcinomas (SCC), eight cervical adenocarcinomas and 39 normal cervical tissues as a control group.

RESULTS

L1 capsid protein was positive in 63.6 % of low-grade CINs and 9.1 % of high-grade CINs; while none of the cervical SCCs, adenocarcinomas or normal cervical tissues showed this marker. In contrast, p16 protein was positive in 81.8 % of low-grade CINs, 90.1 % of high-grade CINs, 90 % of SCCs, 75 % of adenocarcinomas and 10.25 % of normal cervical tissues (p value < 0.001).

CONCLUSION

Despite the presence of interobserver variation in the histopathologic interpretation of cervical lesions, in more instances definite diagnosis is made by routine histopathological examination and these ancillary tests are supportive in follow-up of the patient.

New strategies for human papillomavirus-based cervical screening

Human papillomavirus testing has been shown to be far more sensitive and robust in detecting cervical intraepithelial neoplasia 2 and above (and cervical intraepithelial neoplasia 3 and above) for cervical screening than approaches based on either cytology or visual inspection; however, there are a number of issues that need to be overcome if it is to substantially reduce the morbidity and mortality associated with cervical cancer at the population level. The two main issues are coverage (increasing the number of women who participate in screening) and the management of women who test positive for high-risk human papillomavirus. This article will review the potential for vaginal self-collection to improve coverage and the options for triage of high-risk human papillomavirus-positive women in high-resource and low-resource settings.

Prognostic value of p16-INK4A protein in women with negative or CIN1 histology result: a follow-up study

P16-INK4A overexpression has been proposed as a prognostic marker to manage the follow up of women with positive cytology and/or HPV test but without high-grade cervical intraepithelial neoplasia (CIN2+). This study measures the relative risk (RR) of CIN2+ of p16 positive versus negative in these women. All the women referred to colposcopy from October 2008 to September 2010 with negative or CIN1 colposcopy-guided biopsy were included in the study; women surgically treated or having a CIN2-3 were excluded. All baseline biopsies were dyed with hematoxylin and eosin and p16. Women were followed up according to screening protocols, with cytology or colposcopy at 6 or 12 months. CIN2/3 RRs and 95% confidence intervals (95%CI) were computed. Of 442 eligible women, 369 (83.5%) had at least one follow-up episode. At baseline, 113 (30.6%) were CIN1, 248 (67.2%) negative, and 8 (2.2%) inadequate histology; 293 (79.4%) were p16-negative, 64 (17.3%) p16 positive and 12 (3.2%) not valid. During follow up, we found ten CIN2 and three CIN3; of these, six were p16 positive (sensitivity 46%, 95% CI 19-75). The absolute risk among p16 positives was 9.4/100 compared to 1.7/100 of the p16 negatives (RR 5.5; 95% CI 1.7-17.4). The risk was also higher for CIN1 than for histologically negative women (RR 4.4; 95% CI 1.3-14.3). The RR for p16 in CIN1 did not change (RR 5.2; 95% CI 0.6-47.5). P16 overexpression is a good candidate for modulating follow-up intensity after a negative colposcopy but is limited by its low prospective sensitivity.

Role of p16, CK17, p63, and human papillomavirus in diagnosis of cervical intraepithelial neoplasia and distinction from its mimics

BACKGROUND

Diagnosis of cervical intraepithelial neoplasia (CIN), the precursor forms of cervical cancer, can be tricky and it has led to discrepancy between pathologists in distinguishing them from its mimics such as atypical immature metaplasia (AIM), immature squamous metaplasia (ISM), reactive atypia (RA), atrophy, and basal cell hyperplasia (BCH). To overcome this problem this study aims at using immunohistochemical (IHC) markers p16, p63, CK17, and human papillomavirus (HPV) to differentiate CIN from its mimics.

MATERIALS AND METHODS

This study analyzed 350 cervical samples with histomorphological diagnosis of CIN and its mimics and the utility of IHC markers p16, p63, CK17, and HPV in distinction was analyzed.

RESULTS

p16 showed 67.76% sensitivity and 99.4% specificity whereas HPV showed 57.9% sensitivity and 91.6% specificity in detecting CIN. CK17 and p63 did not show any significance in distinguishing CIN from its mimics. After IHC of AIM cases, 66.7% were reclassified as CIN III, 27.8% as ISM with reactive atypia (ISMRA), and 5.5% case as immature condyloma. In total, 3.7% of diagnosis was upgraded to CIN and 0.6% of pre-IHC diagnosis was downgraded from CIN to reactive lesions.

CONCLUSION

IHC panel comprising p16, p63, CK17, and HPV are useful adjuncts in distinguishing CIN from its mimics particularly when histomorphology has overlapping morphological features.

HPV L1 detection discriminates cervical precancer from transient HPV infection: a prospective international multicenter study

The benefits of cytology-based cervical cancer screening programs in reducing morbidity and mortality are well recognized. Especially, overtreatment of human papillomavirus (HPV) high-risk positive early dysplastic lesions may have a negative impact on reproductive outcomes for fertile women. To optimize the clinical management an objective standard is needed to distinguish precancer that requires treatment, from spontaneously resolving HPV infections. In the current study, we examined the prognostic relevance of HPV-L1 capsid protein analysis with Cytoactiv in an international prospective multicenter study including 908 HPV high-risk positive early dysplastic lesions (LSIL/HSIL) during a follow-up period of 54 months. The clinical end points of the study were histologically confirmed CIN3+ as progression, CIN1/2 for stable disease and repeated negative Pap smears as spontaneous clinical remission. The difference of the clinical outcome of HPV-L1-negative and HPV-L1-positive cases was statistically highly significant (P-value<0.0001) independent of the classification as mild dysplasia (LSIL) and moderate dysplasia (HSIL). Of the HPV-L1-negative HPV high-risk positive mild/moderate dysplasias 84% progressed to CIN3, as compared with only 20% of the HPV-L1-positive cases. The data from our study show that HPV-L1 detection allows to identify transient HPV infections and precancerous lesions within the group of HPV high-risk positive early dysplastic lesions. The high progression rate of HPV-L1-negative mild and moderate dysplasia emphasizes the precancerous nature of these lesions. A close follow-up with colposcopy and histological evaluation is advisable and removal of these lesions should be considered. The low malignant potential of HPV-L1-positive cases, however, indicates transient HPV infection, justifying a watch and wait strategy with cytological follow-up, thus preventing overtreatment especially for women in their reproductive age.

New technologies and procedures for cervical cancer screening

The clearly higher sensitivity and reproducibility of human papillomavirus (HPV) DNA testing for high-grade cervical intraepithelial neoplasia (CIN) has led to widespread calls to introduce it as the primary screening test. The main concern has been its lower specificity, due to the fact that it cannot separate transient from persistent infections, and only the latter are associated with an increased risk of high-grade CIN and cancer. Thus, even proponents of HPV testing generally only recommend it for women over the age of 30 years (or in some cases 35 years). If HPV testing is to reach its full potential, new approaches with better specificity are needed, either as triage tests for HPV positive women or, if the high sensitivity of HPV DNA testing can be maintained, as alternate primary screening modalities. Approaches that may useful in this regard, especially as triage tests, include HPV typing, methylation (and consequent silencing) of host and viral genes, and new cytologic methods, such as p16(INK4a) staining, which attempt to identify proliferating cells. At an earlier stage of development are direct methods based on detection of HPV E6 or E7 proteins. Recent progress and current status of these methods is discussed in this chapter. The current status of visual inspection (VIA and VILI) methods is also surveyed and progress on self-sampling is reviewed. This article forms part of a special supplement entitled "Comprehensive Control of HPV Infections and Related Diseases" Vaccine Volume 30, Supplement 5, 2012.

Role of HPV-16 in Pathogenesis of Oral Epithelial Dysplasia and Oral Squamous Cell Carcinoma and Correlation of p16INK4A Expression in HPV-16 Positive Cases: An Immunohistochemical Study

The objective of current study is to evaluate the role of HPV-16 in the pathogenesis of oral epithelial dysplasias (OED) and oral squamous cell carcinoma (OSCC) by immunohistochemistry (IHC) and to know whether HPV-16 participates in disruption of the regulation of p16 INK4A suppressor protein in OED and OSCC by IHC. Histopathologically diagnosed 20 cases of OED and 20 cases of OSCC were selected from amongst the patients attending the OPD of Vasantdada Patil Dental College and Hospital, Sangli. Biopsy tissue section were then tested for HPV-16 by IHC. HPV-16 positive tissue sections were then again tested by p16 by IHC. Overall 22.5% of cases in our study were found to be positive for HPV 16 which includes 10% of cases of OED and 35% cases of OSCC. Amongst the HPV 16 positive cases, more than 60% of cells were positive for p16INK4A IHC in OED (50%) and OSCC (85.71%). Thus, HPV 16 participates in disruption of the regulation of p16INK4A suppressor protein and can be used as surrogate biomarker for detection of HPV infection in OED and OSCC.

HPV infection in squamous cell carcinomas arising from different mucosal sites of the head and neck region. Is p16 immunohistochemistry a reliable surrogate marker?

BACKGROUND

Human papillomavirus 16 infection has been proven to be associated with oropharyngeal squamous cell carcinomas (SCCs) and is probably the main reason of the reported increase in the incidence. The role of high-risk (HR) HPV for carcinogenesis of other sites in the head and neck awaits confirmation. With the aim to evaluate the prevalence of HPV infection and the reliability of different diagnostic tools in SCCs of different sites, 109 consecutive untreated head and neck SCCs were enrolled, and fresh tumour samples collected.

METHODS

Human papillomavirus DNA was detected by Digene Hybrid Capture 2 (HC2). Human papillomavirus E6 and E7 mRNA were detected by NucliSENS EasyQ HPVv1. P16 expression was evaluated by immunohistochemistry.

RESULTS

In all, 12.84% of cases were infected by HR genotypes and 1.84% by low-risk genotypes. Human papillomavirus 16 accounted for 87% of HR infections. The overall agreement between DNA and RNA detection is 99.1%. Although p16 expression clearly correlates with HPV infection (P=0.0051), the inter-rater agreement is poor (k=0.27). The oropharynx showed the highest HR HPV infection rate (47.6%) and was also the only site in which p16 immunohistochemistry revealed to be a fair, but not excellent, diagnostic assay (κ=0.61).

CONCLUSION

The prognostic role of HR HPV infection in oropharyngeal oncology, with its potential clinical applications, underscores the need for a consensus on the most appropriate detection methods. The present results suggest that viral mRNA detection could be the standard for fresh samples, whereas DNA detection could be routinely used in formalin-fixed, paraffin-embedded samples.

Immunohistochemical detection of human papillomavirus capsid proteins L1 and L2 in squamous intraepithelial lesions: potential utility in diagnosis and management

While cervical cancer screening relies on cervical cytology and high-risk human papillomavirus (HPV) detection, the histologic diagnosis, and specifically lesion grade, is the main parameter that drives clinical management of screen-positive women. Morphologically diagnosed squamous intraepithelial lesions (SIL/CIN) regress spontaneously in more than half of the cases, but identifying those likely to persist and progress is not currently possible based upon morphology. Lack of major capsid protein L1 expression has been suggested as a feature in progressive lesions, whereas expression of the minor capsid protein L2 has not been extensively evaluated. The goal of this study is to evaluate immunohistochemical expression of L1 and L2 in SILs in correlation with lesion grade. A total of 150 cervical specimens with SILs were selected based on HPV 16 or HPV 18 detection by Q-PCR. These included 89 low-grade SILs (LSIL/CIN 1) and 123 high-grade SILs (75 HSIL/CIN 2 and 48 HSIL/CIN 3). More than one lesion/grade was identified in 53 specimens. The presence and grade of SIL was determined by a panel of pathologists. Capsid protein expression was assessed by immunohistochemistry using MAB 837 for L1 and RG-1 for L2. Lesions of different grades in the same specimen were scored separately. Expression of capsid proteins was detected in 34/89 (40%) LSIL/CIN 1, 5/75 (6%) HSIL/CIN 2 and none of 48 HSIL/CIN 3. L1 and L2 were co-expressed in the same area of the lesion in 22 cases. In addition, L1 alone was expressed in 6 lesions and L2 alone in 11 lesions. Among the cases with multiple lesion grades in the same specimen, none with HSIL/CIN 3 expressed capsid proteins in any portion/grade of the lesion. HPV capsid proteins are expressed almost exclusively in LSIL/CIN 1 and rarely in HSIL/CIN 2. Additional studies are warranted to examine lack of L1 and L2 expression in LSIL/CIN 1 as a predictor of persistence or progression to HSIL/CIN 3, the precursor of cervical cancer.

Amplification of the telomerase RNA component gene as a new genetic marker for disease progression and prognosis in esophageal squamous cell carcinoma

Amplification of the human telomerase RNA component (TERC) gene was found in esophageal squamous cell carcinoma (ESCC). However, its roles in the progression and prognosis of ESCC have not been well understood. The amplification of TERC in normal mucosa, low-grade and high-grade intraepithelial neoplasia, and invasive ESCC samples were evaluated using a fluorescence in situ hybridization assay. The amplification of TERC invariably occurred in high-grade intraepithelial neoplasia and invasive ESCC, partially occurred in low-grade intraepithelial neoplasia specimens, and seldom occurred in normal mucosa. The average signal ratio of TERC to chromosome 3 centromere-specific probe (TERC/CSP3) was 1.00 ± 0.01 (average ± standard deviation) in normal mucosas, 1.01 ± 0.08 in low-grade intraepithelial neoplasias, 1.39 ± 0.26 in high-grade intraepithelial neoplasias, and 1.56 ± 0.41 in invasive ESCC. High TERC/CSP3 ratio was positively associated with lymph node metastasis (P = 0.005) and advanced tumor stage (P = 0.045). Patients with high amplification of TERC had poor survival (P = 0.01). The amplification of TERC could be used as a new genomic marker for disease progression and prognosis of ESCC. The amplified TERC gene may be a potential therapeutic target for ESCC.

Role of protein biomarkers in the detection of high-grade disease in cervical cancer screening programs

Since the Pap test was introduced in the 1940s, there has been an approximately 70% reduction in the incidence of squamous cell cervical cancers in many developed countries by the application of organized and opportunistic screening programs. The efficacy of the Pap test, however, is hampered by high interobserver variability and high false-negative and false-positive rates. The use of biomarkers has demonstrated the ability to overcome these issues, leading to improved positive predictive value of cervical screening results. In addition, the introduction of HPV primary screening programs will necessitate the use of a follow-up test with high specificity to triage the high number of HPV-positive tests. This paper will focus on protein biomarkers currently available for use in cervical cancer screening, which appear to improve the detection of women at greatest risk for developing cervical cancer, including Ki-67, p16^INK4a, BD ProEx C, and Cytoactiv HPV L1.

An analysis on the combination expression of HPV L1 capsid protein and p16INK4a in cervical lesions

Human papillomavirus (HPV) infection in cervix is the most important reason for cervical cancer, but only 2% cervical HPV infection will develop into cervical cancer. So how to identify patients at risk of progressive cervical lesions from those infected with HPV to avoid over treatment is a big issue in clinic. The aims of this study were to detect the expression of HPV L1 capsid protein and p16(INK4a) in cervical lesions and to investigate the combination expression of HPV L1 capsid protein and p16(INK4a) in cervical lesions and its diagnostic efficiency in clinic. Immunochemical method was used to detect the expression of HPV L1 capsid protein and p16(INK4a) in 169 cases of abnormal cytology. Histopathologic test was performed to identify cervical lesions of all the cases. chi(2) test and spearman's rank correlation were used for statistical analysis. The diagnostic sensitivity, specificity, positive predictive values (PPV), negative predictive values (NPV), accuracy, and the area under the receive operating characteristic (ROC) curve (denoted by A(Z)) were calculated with SPSS 13.0. All the statistical tests were two sided at the 5% level of significance. L1 expression decreased (P < 0.001), but p16(INK4a) expression increased (P < 0.001) with histopathologic diagnosis increasing. The expression rates of HPV L1 capsid protein, p16(INK4a), and L1(-)/p16(+) in cervical intraepithelial neoplasia (CIN)2, CIN3, and squamous-cell carcinoma were statistically different from those in CIN1 (P < 0.001). The expressions of HPV L1 capsid protein, L1(+)/p16(+), L1(+)/p16(-), and L1(-)/p16(-) were negatively correlated with the severity of cervical lesions (P < 0.001), whereas the expressions of p16(INK4a) and L1(-)/p16(+) were positively correlated with the severity of cervical lesions (P < 0.001). The specificity and A(Z) of combining L1 with p16 (INK4a) were statistically higher than L1 or p16 (INK4a) alone (P < 0.05). L1 and p16(INK4a) are useful biomarkers for the early diagnosis of cervical lesions. The combination of L1 and p16(INK4a) has a higher diagnostic accuracy than L1 or p16(INK4a) alone in diagnosis of cervical lesions.

Immunohistological analysis of HPV L1 capsid protein and p16 protein in low-grade dysplastic lesions of the uterine cervix

Human papillomavirus (HPV) L1 capsid protein (L1) is associated with the productive phase of HPV infection. However, the expression of L1 and its relationship to p16 expression, a surrogate marker for HPV infection, are unknown. We examined the relationship between L1 and p16 expression in cervical intraepithelial neoplasia. Tissues were divided into four categories: regressive lesions (n=48), progressive lesions (n=40), and randomly selected CIN1-2 (n=67) and CIN3 (n=44). P16 positivity in the progression cases was significantly higher than that in the regression cases, and p16 positivity in the CIN3 cases was significantly higher than that in any other categories. L1 positivity was not significant between each category. The staining pattern was divided into the following four groups: L1-/p16-, L1+/p16-, L1+/p16+, L1-/p16+. The L1-/p16- pattern was significantly associated with the regression nature in CIN1-2. Some CIN3 cases showing a feature of L1+/p16+, which are still HPV-productive, are likely to exist. The combination of both L1 and p16 may be useful in the evaluation of the progression risk of low-grade cervical dysplasia.

MOLECULAR MARKERS OF EARLY CERVICAL NEOPLASIA

Pure morphological distinction of high-grade squamous intraepithelial lesions (HSILs) from their mimics can be challenging. Diagnosis can be difficult with nonconventional HSILs associated with a metaplastic phenotype, squamous intraepithelial lesions (SILs) that defy precise classification such as "eosinophilic dysplasias", and those that overlap with columnar neoplasms, including stratified variants of adenocarcinoma in situ ("SMILE"). Gene expression and protein profiling have identified biomarkers with the potential to decrease diagnostic variability and increase specificity of histological and cytological analysis. Among the ones clinically useful for HSIL detection are p16(INK4A) and MIB-1 which complement each other, differentiating SIL from normal/atrophic (MIB-1 low) or reactive/immature metaplastic (p16(INK4A) scattered) epithelium. Additional markers, including ProEx(TM) C, have been proposed but their added value is yet to be established. In the final analysis, biomarkers are most helpful for distinguishing benign immature or atrophic proliferations from HSIL. The distinction of LSIL from HSIL must be made on the hematoxylin and eosin-stained section and should be made with care, given the potential consequences of a diagnosis of CIN2 or CIN3.

Histological 'progression' from low (LSIL) to high (HSIL) squamous intraepithelial lesion is an uncommon event and an indication for quality assurance review

An accurate assessment of 'progression' from a low (LSIL) to high (HSIL) grade squamous intraepithelial lesion (cervical intraepithelial neoplasia (CIN)2 or CIN3) of the cervix is critical to ascertaining HSIL outcome risk, the value of predictive biomarkers, and the need for excisional therapy. We obtained biopsy outcome data on a series of initially diagnosed LSIL to assess this risk. Consecutive biopsy diagnoses of LSIL were obtained from the archives, and the frequency of HSIL biopsy outcomes were ascertained by record and histological review. Then, a 'numerical severity score' was recorded for each diagnosis: LSIL (1-2), CIN2 (3-4) and CIN3 (5-6) with lower and higher values corresponding to the degree (low vs high) of histological severity within each category, respectively. Of 264 initial LSILs, 29 (11%) were reported with an HSIL outcome. However, histological review of 21 of these HSILs confirmed only 8 (38%) HSIL diagnoses by review with the numerical severity score: three cases scored as 5, three cases scored as 4, and two cases scored as 3; the remaining 13 cases were assigned a numerical severity score of 1 or 2. P16 immunostains of corresponding previous and subsequent biopsies were discordant in 4 of 12 cases (33%). In a blind review of a randomly selected series of HSILs from the same practice, HSIL was significantly more likely to be confirmed on re-review (10 of 13 (77%), P=0.024). These findings show that confirmed HSIL outcomes (on review) following an LSIL biopsy are infrequent ( approximately 3%). A diagnosis of HSIL following an LSIL should always be reviewed, as this diagnostic pairing may more likely be associated with a diagnostic error.

Diagnostic value of p16INK4A, Ki-67, and human papillomavirus L1 capsid protein immunochemical staining on cell blocks from residual liquid-based gynecologic cytology specimens

BACKGROUND

This study was conducted to evaluate the reliability and role of cell block preparations in the diagnosis of neoplastic and preneoplastic lesions of the cervix and to improve the value of cell block preparations in diagnosing and predicting the prognosis of cervical lesions through immunostaining of p16INK4A (p16), Ki-67, and human papillomavirus (HPV) L1 capsid protein (HPV L1).

METHODS

In total, 138 specimens were diagnosed on liquid-based cytology (LBC) and cell block preparations, and 63 specimens were subjected subsequently to tissue follow-up and immunostaining for p16, Ki-67, and HPV L1 on cell block sections.

RESULTS

In 42 specimens that were diagnosed as low-grade squamous intraepithelial lesion, high-grade squamous intraepithelial lesion (HSIL), and squamous cell carcinoma (SCC) on cell blocks, 38 specimens (90.5%) were confirmed by histopathologic reports, and there was slightly better than 81.6% agreement between LBC and tissue follow-up. Immunointensity and cells that were positive for p16 were enhanced according to increased pathologic grade and differed statistically between cervical intraepithelial neoplasia 1 (CIN-1) and CIN-2/CIN-3 as well as SCC. The positive rates of HPV L1 decreased gradually according to the severity of cervical neoplasia, and HPV L1/p16 expression patterns were related to the severity of cervical lesions.

CONCLUSIONS

The cell block preparation technique was complementary to LBC, and the authors concluded that the application of LBC combined with cell block preparations may improve the diagnostic accuracy of cytology. Immunostaining for p16 and Ki-67 on cell block preparations can help to improve the diagnostic accuracy of HSIL and SCC. A combined expression pattern of p16 and HPV L1 may serve as a valuable index for predicting prognosis and follow-up of cervical dysplastic lesions.

HPV vaccine protein L1 predicts disease outcome of high-risk HPV+ early squamous dysplastic lesions

Prediction of the clinical outcome of nonadvanced, early dysplastic lesions is one of the unresolved problems of cervical cancer screening programs. We examined the influence of human papillomavirus (HPV) L1 capsid protein detection in a randomized, prospective study of 187 high-risk HPV+ early dysplastic lesions during 36 to 46 months. The difference in the clinical outcome of the HPV L1- cases and the HPV L1+ cases was highly statistically significant (P < .0001) and independent of the classification of low-grade squamous intraepithelial lesion (mild dysplasia) and high-grade squamous intraepithelial lesion of the moderate dysplastic type. L1+ mild and moderate dysplasias, reflecting productive HPV infection, showed low malignant potential, justifying a wait-and-watch strategy to prevent overtreatment, especially in young women. L1- early dysplastic lesions, as nonproductive infections or precancerous lesions, have a high malignancy potential and close follow-up with colposcopy and histologic evaluation should be advised.

Value of p16(INK4a) as a marker of progression/regression in cervical intraepithelial neoplasia grade 1

OBJECTIVE

The objective of this study was to evaluate the usefulness of p16(INK4a) staining to classify cervical intraepithelial neoplasia grade 1 according to its progression/regression risk.

STUDY DESIGN

Patients with a histologic diagnosis of cervical intraepithelial neoplasia grade 1 were prospectively recruited (n = 138). Simultaneous detection of high-risk human papillomaviruses and p16(INK4a) evaluation were performed. Follow-up was conducted every 6 months by cytology and colposcopy and annually by high-risk human papillomavirus testing, for at least 12 months (mean, 29.0). Progression was defined as a histologic diagnosis of cervical intraepithelial neoplasia grades 2-3, regression as a negative cytology and high-risk human papillomaviruses, and persistence as a cytologic result of low-grade squamous intraepithelial lesions and/or a positive test for high-risk human papillomaviruses.

RESULTS

Progression was observed in 14 women (10.1%), 66 (47.6%) regressed, and 58 (42.0%) had a persistent disease. p16(INK4a) was positive in 77 (55.8%) initial biopsy specimens. Progression to cervical intraepithelial neoplasia grades 2-3 was identified in 14 of 77 (18.2%) women with positive and none of 61 (0.00%) women with negative p16(INK4a) immunostaining (P < .001).

CONCLUSION

p16(INK4a) negative cervical intraepithelial neoplasia grade 1 lesions rarely progress and may benefit from a less intensive follow-up.