Dirk van Niekerk

A randomized controlled trial of Human Papillomavirus (HPV) testing for cervical cancer screening: trial design and preliminary results (HPV FOCAL Trial)

BackgroundIn the HPV FOCAL trial, we will establish the efficacy of hr-HPV DNA testing as a stand-alone screening test followed by liquid based cytology (LBC) triage of hr-HPV-positive women compared to LBC followed by hr-HPV triage with ≥ CIN3 as the outcome.Methods/DesignHPV-FOCAL is a randomized, controlled, three-armed study over a four year period conducted in British Columbia. It will recruit 33,000 women aged 25-65 through the provinces population based cervical cancer screening program. Control arm: LBC at entry and two years, and combined LBC and hr-HPV at four years among those with initial negative results and hr-HPV triage of ASCUS cases; Two Year Safety Check arm: hr-HPV at entry and LBC at two years in those with initial negative results with LBC triage of hr-HPV positives; Four Year Intervention Arm: hr-HPV at entry and combined hr-HPV and LBC at four years among those with initial negative results with LBC triage of hr-HPV positive casesDiscussionTo date, 6150 participants have a completed sample and epidemiologic questionnaire. Of the 2019 women enrolled in the control arm, 1908 (94.5%) were cytology negative. Women aged 25-29 had the highest rates of HSIL (1.4%). In the safety arm 92.2% of women were hr-HPV negative, with the highest rate of hr-HPV positivity found in 25-29 year old women (23.5%). Similar results were obtained in the intervention arm HPV FOCAL is the first randomized trial in North America to examine hr-HPV testing as the primary screen for cervical cancer within a population-based cervical cancer screening program.Trial RegistrationInternational Standard Randomised Controlled Trial Number Register, ISRCTN79347302

Exploratory Analysis of Quantitative Histopathology of Cervical Intraepithelial Neoplasia: Objectivity, Reproducibility, Malignancy-Associated Changes, and Human Papillomavirus

Background: As part of a project to evaluate emerging optical technologies for cervical neoplasia, our group is performing quantitative histopathological analyses of biopsy specimens from 1,190 patients. Objectives in the interim analysis are (a) quantitatively assessing progression of the neoplastic process of cervical intraepithelial neoplasia (CIN)/squamous intraepithelial lesions (SIL), (b) detecting malignancy‐associated changes (MACs), and (c) phenotypically measuring human papillomavirus (HPV) detected by DNA testing.

Randomized clinical evaluation of self-screening for anal cancer precursors in men who have sex with men

Background Self-collection of anorectal swab specimens could greatly facilitate the completion of prerequisite studies and future implementation of anal cancer screening among men who have sex with men (MSM). We therefore compared self- versus clinician- collection procedures with respect to specimen adequacy for cytological evaluation, concordance of paired cytological results, and concordance of cytological with biopsy results. Methods Paired self- and clinician- collected anorectal Dacron® swabs for liquid-based (Thin Prep®) cytological evaluation were collected in random sequence from a mostly HIV-1 seronegative cohort of young MSM in Vancouver. Slides were reviewed by one cytopathologist. Presence of any cytological abnormality (atypical squamous cells of uncertain significance, ASCUS, or above) prompted referral for high-resolution anoscopy and possible biopsy. Results Among 222 patient-clinician specimen pairs, most were adequate for cytological evaluation, though self-collected specimens were less likely to be so (83% versus 92%, McNemars test p < 0.001). Cytological abnormalities, noted in 47 (21%) of self-collected and 47 (21%) of clinician-collected specimens (with fair agreement, kappa = 0.414) included, respectively: ASCUS (5%, 5%), and low-grade (13%, 13%) and high-grade (3%, 3%) squamous intraepithelial lesions. Among 12 men with biopsy-confirmed high-grade neoplasia, most had abnormal cytological results (including 6 patient and 9 clinician swabs) but few (2 patient and 1 clinician swab) were high-grade. Conclusion Self-collection of anorectal swab specimens for cytologic screening in research and possibly clinical settings appears feasible, particularly if specimen adequacy can be further improved. The severity of biopsy-confirmed anorectal disease is seriously underestimated by cytological screening, regardless of collector.

Accuracy of optical spectroscopy for the detection of cervical intraepithelial neoplasia: Testing a device as an adjunct to colposcopy

Testing emerging technologies involves the evaluation of biologic plausibility, technical efficacy, clinical effectiveness, patient satisfaction, and cost‐effectiveness. The objective of this study was to select an effective classification algorithm for optical spectroscopy as an adjunct to colposcopy and obtain preliminary estimates of its accuracy for the detection of CIN 2 or worse. We recruited 1,000 patients from screening and prevention clinics and 850 patients from colposcopy clinics at two comprehensive cancer centers and a community hospital. Optical spectroscopy was performed, and 4,864 biopsies were obtained from the sites measured, including abnormal and normal colposcopic areas. The gold standard was the histologic report of biopsies, read 2 to 3 times by histopathologists blinded to the cytologic, histopathologic, and spectroscopic results. We calculated sensitivities, specificities, receiver operating characteristic (ROC) curves, and areas under the ROC curves. We identified a cutpoint for an algorithm based on optical spectroscopy that yielded an estimated sensitivity of 1.00 [95% confidence interval (CI) = 0.92–1.00] and an estimated specificity of 0.71 [95% CI = 0.62–0.79] in a combined screening and diagnostic population. The positive and negative predictive values were 0.58 and 1.00, respectively. The area under the ROC curve was 0.85 (95% CI = 0.81–0.89). The per‐patient and per‐site performance were similar in the diagnostic and poorer in the screening settings. Like colposcopy, the device performs best in a diagnostic population. Alternative statistical approaches demonstrate that the analysis is robust and that spectroscopy works as well as or slightly better than colposcopy for the detection of CIN 2 to cancer.

HPV for cervical cancer screening (HPV FOCAL): Complete Round 1 results of a randomized trial comparing HPV‐based primary screening to liquid‐based cytology for cervical cancer

Complete Round 1 data (baseline and 12‐month follow‐up) for HPV FOCAL, a randomized trial establishing the efficacy of HPV DNA testing with cytology triage as a primary screen for cervical cancer are presented. Women were randomized to one of three arms: Control arm – Baseline liquid‐based cytology (LBC) with ASCUS results triaged with HPV testing; Intervention and Safety arms – Baseline HPV with LBC triage for HPV positives. Results are presented for 15,744 women allocated to the HPV (intervention and safety combined) and 9,408 to the control arms. For all age cohorts, the CIN3+ detection rate was higher in the HPV (7.5/1,000; 95%CI: 6.2, 8.9) compared to the control arm (4.6/1,000; 95%CI: 3.4, 6.2). The CIN2+ detection rates were also significantly higher in the HPV (16.5/1,000; 95%CI: 14.6, 18.6) vs. the control arm (10.1/1,000; 95%CI: 8.3, 12.4). In women ≥35 years, the overall detection rates for CIN2+ and CIN3+ were higher in the HPV vs. the control arm (CIN2+:10.0/1,000 vs. 5.2/1,000; CIN3+: 4.2/1,000 vs. 2.2/1,000 respectively, with a statistically significant difference for CIN2+). HPV testing detected significantly more CIN2+ in women 25–29 compared to LBC (63.7/1,000; 95%CI: 51.9, 78.0 vs. 32.4/1,000; 95%CI: 22.3, 46.8). HPV testing resulted in significantly higher colposcopy referral rates for all age cohorts (HPV: 58.9/1,000; 95%CI: 55.4, 62.7 vs. control: 30.9/1,000; 95%CI: 27.6, 34.6). At completion of Round 1 HPV‐based cervical cancer screening in a population‐based program resulted in greater CIN2+ detection of across all age cohorts compared to LBC screening.

Up regulation in gene expression of chromatin remodelling factors in cervical intraepithelial neoplasia.

BackgroundThe highest rates of cervical cancer are found in developing countries. Frontline monitoring has reduced these rates in developed countries and present day screening programs primarily identify precancerous lesions termed cervical intraepithelial neoplasias (CIN). CIN lesions described as mild dysplasia (CIN I) are likely to spontaneously regress while CIN III lesions (severe dysplasia) are likely to progress if untreated. Thoughtful consideration of gene expression changes paralleling the progressive pre invasive neoplastic development will yield insight into the key casual events involved in cervical cancer development.ResultsIn this study, we have identified gene expression changes across 16 cervical cases (CIN I, CIN II, CIN III and normal cervical epithelium) using the unbiased long serial analysis of gene expression (L-SAGE) method. The 16 L-SAGE libraries were sequenced to the level of 2,481,387 tags, creating the largest SAGE data collection for cervical tissue worldwide. We have identified 222 genes differentially expressed between normal cervical tissue and CIN III. Many of these genes influence biological functions characteristic of cancer, such as cell death, cell growth/proliferation and cellular movement. Evaluation of these genes through network interactions identified multiple candidates that influence regulation of cellular transcription through chromatin remodelling (SMARCC1, NCOR1, MRFAP1 and MORF4L2). Further, these expression events are focused at the critical junction in disease development of moderate dysplasia (CIN II) indicating a role for chromatin remodelling as part of cervical cancer development.ConclusionWe have created a valuable publically available resource for the study of gene expression in precancerous cervical lesions. Our results indicate deregulation of the chromatin remodelling complex components and its influencing factors occur in the development of CIN lesions. The increase in SWI/SNF stabilizing molecule SMARCC1 and other novel genes has not been previously illustrated as events in the early stages of dysplasia development and thus not only provides novel candidate markers for screening but a biological function for targeting treatment.

Women's intentions to receive cervical cancer screening with primary human papillomavirus testing.

We explored the potential impact of human papillomavirus (HPV) testing on womens intentions to be screened for cervical cancer in a cohort of Canadian women. Participants aged 25–65 years from an ongoing trial were sent a questionnaire to assess womens intentions to be screened for cervical cancer with HPV testing instead of Pap smears and to be screened every 4 years or after 25 years of age. We created scales for attitudes about HPV testing, perceived behavioral control, and direct and indirect subjective norms. Demographic data and scales that were significantly different (p < 0.1) between women who intended to be screened with HPV and those who did not intend were included in a stepwise logistic regression model. Of the 2,016 invitations emailed, 1,538 were received, and 981 completed surveys for a response rate of 63% (981/1,538). Eighty‐four percent of women (826/981) responded that they intended to attend for HPV‐based cervical cancer screening, which decreased to 54.2% when the screening interval was extended, and decreased further to 51.4% when screening start was delayed to age of 25. Predictors of intentions to undergo screening were attitudes (odds ratio [OR]: 1.22; 95% confidence interval [CI]: 1.15, 1.30), indirect subjective norms (OR: 1.02; 95% CI: 1.01, 1.03) and perceived behavioral control (OR: 1.16; 95% CI: 1.10; 1.22). Intentions to be screened for cervical cancer with HPV testing decreased substantially when the screening interval was extended and screening started at age of 25. Use of primary HPV testing may optimize the screening paradigm, but programs should ensure robust planning and education to mitigate any negative impact on screening attendance rates.

Illustrated instructions for self-collection of anorectal swab specimens and their adequacy for cytological examination.

Background: Self-collection of anorectal swab specimens would facilitate screening for anal cancer precursors and sexually transmitted rectal infections among men who have sex with men (MSM). However, pictorial guides for self-collection were not previously available. Goals: Develop and field test a set of illustrated self-collection instructions. Design: Cross-sectional study of community-recruited MSM who were naïve with regard to collection of specimens for anal cytology. Results: Among 222 self- and clinician-collected swab pairs provided by mostly human immunodeficiency virus (HIV)-1 seronegative MSM (median age, 31.5 years), most specimens were adequate for cytologic evaluation, though self-collected swabs were less likely to be so (83% versus 92%, P = <0.001). The illustrated instructions were reportedly essential, but having used them, men rated their understanding of the self-collection procedure as very high. Conclusions: Provided with illustrated instructions, most MSM who are naïve to the technique can self-collect anorectal swab specimens that are suitable for screening.

Reduction in cervical intraepithelial neoplasia in young women in British Columbia after introduction of the HPV vaccine: An ecological analysis

We report on the rates of cervical intraepithelial neoplasia (CIN) in young women aged 15–22 years of age in British Columbia before and after the introduction of an HPV vaccine program. Rates of cervical intraepithelial neoplasia (CIN) 2+ for each age stratum (15–22) in the calendar years 2004–2012 for the province of British Columbia were obtained from the BC Cancer Agency‘s population‐based cervical cancer program. Incidence rate ratios (IRR) of CIN2+ were described and compared before and after HPV vaccine program introduction in cohorts born in vaccine eligible years, and in non‐vaccine eligible years using piece‐wise Poisson regression analysis, and adjusted for age. Between 2004 and 2012, rates of CIN2 and CIN2+ in young women aged 15–22 years in the province of British Columbia have decreased overall. After the introduction of the HPV vaccine program, the age adjusted IRR for CIN2+ for young women aged 15–17 years decreased significantly from 0.91 (95% CI: 0.86–0.98 p < 0.01) to 0.36 (95% CI: 0.18–0.73 p < 0.01). During the same time period, no similar reduction was found in young women 18–22 years. After introduction of HPV vaccine program, IRR for CIN2+ in young women 15–17 was significantly reduced for CIN2+ (0.14; 95% CI: 0.04– 0.47; p < 0.01) and CIN2 (0.1; 95% CI: 0.02–0.54; p < 0.01). This ecological analysis shows a significant reduction in CIN2+ lesions in young women aged 15–17 years in British Columbia after the introduction of the HPV vaccine in young women despite vaccine uptake levels below 70%.

Flat Ductal Intraepithelial Neoplasia 1A Diagnosed at Stereotactic Core Needle Biopsy: Is Excisional Biopsy Indicated?

OBJECTIVE This study correlates ductal intraepithelial neoplasia (DIN) 1A diagnosed at stereotactic spring core needle biopsy (CNB) or vacuum-assisted biopsy (VAB) with the subsequent surgical histologic results or long-term follow-up imaging findings to predict the likelihood of upgrade to ductal carcinoma in situ (DCIS) or invasive carcinoma. MATERIALS AND METHODS Stereotactic imaging-guided CNBs and VABs were performed principally for assessment of microcalcifications seen on mammography. DIN 1A diagnoses made at CNB or VAB were correlated with subsequent excisional biopsy results or imaging follow-up. Patients were included only if there was no concomitant CNB or VAB diagnosis of DIN 1B, atypical lobular hyperplasia, lobular carcinoma in situ or DCIS, papillary lesion, or invasive carcinoma. Surgical biopsy results were obtained for 239 patients. Upgrade was defined as a diagnosis of DCIS or invasive carcinoma at surgery. Patients who did not undergo surgical excision were followed with imaging. RESULTS An upgrade rate of 4.2% (10 lesions in 239 patients) is reported. The remaining samples (229/239) had a surgical diagnosis of DIN 1A or DIN 1B, lobular carcinoma in situ, or a benign finding with no atypia. CONCLUSION The upgrade rate of DIN 1A diagnosed at CNB or VAB was 4.2%. These results indicate it may be reasonable to avert immediate surgery in favor of short-term imaging follow-up.