Grading immunohistochemical markers p16INK4a and HPV E4 identifies productive and transforming lesions caused by low- and high-risk HPV within high-grade anal squamous intraepithelial lesions.

OBJECTIVES: Because current guidelines recognise high-grade anal squamous intraepithelial lesions (HSILs) and low-grade SILs (LSILs), and recommend treatment of all HSILs although not all progress to cancer, this study aims to distinguish transforming and productive HSILs by grading immunohistochemical (IHC) biomarkers p16INK 4a (p16) and E4 in low-risk human papillomavirus (lrHPV) and high-risk (hr)HPV-associated SILs as a potential basis for more selective treatment. METHODS: Immunostaining for p16 and HPV E4 was performed and graded in 183 biopsies from 108 HIV-positive men who have sex with men. The causative HPV genotype of the worst lesion was identified using the HPV SPF10-PCR-DEIA-LiPA25 version 1 system, with laser capture microdissection for multiple infections. The worst lesions were scored for p16 (0-4) to identify activity of the hrHPV E7 gene, and panHPV E4 (0-2) to mark HPV production and life cycle completion. RESULTS: There were 37 normal biopsies, 60 LSILs and 86 HSILs, with 85% of LSILs caused by lrHPV and 93% of HSILs by hrHPV. No normal biopsy showed E4, but 43% of LSILs and 37% of HSILs were E4 positive. No differences in E4 positivity rates were found between lrHPV and hrHPV lesions. Most of the lesions caused by lrHPV (90%) showed very extensive patchy p16 staining; p16 grade in HSILs was variable, with frequency of productive HPV infection dropping with increasing p16 grade. CONCLUSIONS: Combined p16/E4 IHC identifies productive and nonproductive HSILs associated with hrHPV within the group of HSILs defined by the Lower Anogenital Squamous Terminology recommendations. This opens the possibility of investigating selective treatment of advanced transforming HSILs caused by hrHPV, and a 'wait and see' policy for productive HSILs. What's already known about this topic? For preventing anal cancer in high-risk populations, all patients with high-grade squamous intraepithelial lesions (HSILs) are treated, even though this group of lesions is heterogeneous, the histology is variable and regression is frequent. What does this study add? By adding human papillomavirus (HPV) E4 immunohistochemistry to p16 INK4a (p16), and grading expression of both markers, different biomarker expression patterns that reflect the heterogeneity of HSILs can be identified. Moreover, p16/E4 staining can separate high-risk HPV-associated HSILs into productive and more advanced transforming lesions, providing a potential basis for selective treatment.

Performance of CADM1/MAL-methylation analysis for monitoring of women treated for high-grade CIN.

INTRODUCTION: Recent studies have shown that CADM1/MAL-methylation testing detects high-grade CIN lesions with a high short-term progression risk for cervical cancer. Women treated for CIN2/3 are at risk of post-treatment disease, representing either persistent (incompletely treated) or incident (early onset) lesions. Here, we evaluated CADM1/MAL-methylation analysis as potential tool for detecting recurrent high-grade CIN lesions (rCIN2/3). METHODS AND MATERIALS: A multicenter prospective clinical cohort study was conducted among 364 women treated for CIN2/3. Cervical scrapes were taken prior to treatment, and six and 12months post-treatment and tested for cytology, hrHPV (plus genotype) and CADM1/MAL-methylation. When at six months either of these tests was positive, a colposcopy-directed biopsy was obtained. At 12months, all women underwent an exit-colposcopy with biopsy. In case of rCIN2/3, re-treatment was done. RESULTS: We found 28 rCIN2 (7.7%) and 14 rCIN3 (3.8%), resulting in a total recurrence rate of 11.5%. All 14 women with rCIN3 and 15/28 (54%) with rCIN2 showed hrHPV type-persistence. Of these, 9/14 (64%) rCIN3 and 8/15 (53%) rCIN2 were CADM1/MAL-methylation positive. All incident rCIN2, characterized by hrHPV genotype-switch, were CADM1/MAL-methylation negative. All three carcinomas found after re-treatment were CADM1/MAL-methylation positive. CADM1/MAL-methylation positivity at both baseline and follow-up significantly increased the risk of ≥rCIN3 (from 0.7% to 18.4%), and ≥rCIN2 (from 8.2% to 36.8%), compared to a consistently CADM1/MAL-methylation negative result (p-value: <0.001). CONCLUSION: Post-treatment monitoring by CADM1/MAL-methylation analysis identifies women with an increased risk of rCIN2/3. Our results confirm previous data indicating that CADM1/MAL-methylation analysis provides a high reassurance against cancer.