Adjunctive colposcopy technologies for examination of the uterine cervix--DySIS, LuViva Advanced Cervical Scan and Niris Imaging System: a systematic review and economic evaluation

BACKGROUND

Women in England (aged 25-64 years) are invited for cervical screening every 3-5 years to assess for cervical intraepithelial neoplasia (CIN) or cancer. CIN is a term describing abnormal changes in the cells of the cervix, ranging from CIN1 to CIN3, which is precancerous. Colposcopy is used to visualise the cervix. Three adjunctive colposcopy technologies for examination of the cervix have been included in this assessment: Dynamic Spectral Imaging System (DySIS), the LuViva Advanced Cervical Scan and the Niris Imaging System.

OBJECTIVE

To determine the clinical effectiveness and cost-effectiveness of adjunctive colposcopy technologies for examination of the uterine cervix for patients referred for colposcopy through the NHS Cervical Screening Programme.

DATA SOURCES

Sixteen electronic databases [Allied and Complementary Medicine Database (AMED), BIOSIS Previews, Cochrane Database of Systematic Reviews (CDSR), Cochrane Central Register of Controlled Trials (CENTRAL), Cumulative Index to Nursing and Allied Health Literature (CINAHL), Database of Abstracts of Reviews of Effects (DARE), EMBASE, Health Management Information Consortium (HMIC), Health Technology Assessment (HTA) database; Inspec, Inside Conferences, MEDLINE, NHS Economic Evaluation Database (NHS EED), PASCAL, Science Citation Index Expanded (SCIE) and Science Citation Index (SCI) - Conference Proceedings], and two clinical trial registries [ClinicalTrials.gov and Current Controlled Trials (CCT)] were searched to September-October 2011.

REVIEW METHODS

Studies comparing DySIS, LuViva or Niris with conventional colposcopy were sought; a narrative synthesis was undertaken. A decision-analytic model was developed, which measured outcomes in terms of quality-adjusted life-years (QALYs) and costs were evaluated from the perspective of the NHS and Personal Social Services with a time horizon of 50 years.

RESULTS

Six studies were included: two studies of DySIS, one study of LuViva and three studies of Niris. The DySIS studies were well reported and had a low risk of bias; they found higher sensitivity with DySIS (both the DySISmap alone and in combination with colposcopy) than colposcopy alone for identifying CIN2+ disease, although specificity was lower with DySIS. The studies of LuViva and Niris were poorly reported and had limitations, which indicated that their results were subject to a high risk of bias; the results of these studies cannot be considered reliable. The base-case cost-effectiveness analysis suggests that both DySIS treatment options are less costly and more effective than colposcopy alone in the overall weighted population; these results were robust to the ranges tested in the sensitivity analysis. DySISmap alone was more costly and more effective in several of the referral groups but the incremental cost-effectiveness ratio (ICER) was never higher than £1687 per QALY. DySIS plus colposcopy was less costly and more effective in all reasons for referral. Only indicative analyses were carried out on Niris and LuViva and no conclusions could be made on their cost-effectiveness.

LIMITATIONS

The assessment is limited by the available evidence on the new technologies, natural history of the disease area and current treatment patterns.

CONCLUSIONS

DySIS, particularly in combination with colposcopy, has higher sensitivity than colposcopy alone. There is no reliable evidence on the clinical effectiveness of LuViva and Niris. DySIS plus colposcopy appears to be less costly and more effective than both the DySISmap alone and colposcopy alone; these results were robust to the sensitivity analyses undertaken. Given the lack of reliable evidence on LuViva and Niris, no conclusions on their potential cost-effectiveness can be drawn. There is some uncertainty about how generalisable these findings will be to the population of women referred for colposcopy in the future, owing to the introduction of the human papillomavirus (HPV) triage test and uptake of the HPV vaccine.

The role of low-level magnification in visual inspection with acetic acid for the early detection of cervical neoplasia

Several studies have investigated the accuracy of naked eye visual inspection with acetic acid (VIA) in the early detection of cervical neoplasia. It is not clear whether low-level (2-4x) magnification (VIAM) can improve the sensitivity and specificity of VIA. The accuracy of both VIA and VIAM, provided by independent health workers, were evaluated in three cross-sectional studies involving 18,675 women aged 25-65 years in Kolkata and Mumbai in India. All screened women were investigated with colposcopy and biopsies were obtained based on colposcopy findings. The final disease status was based on the reference standard of histology (if biopsies had been taken) or colposcopy. Data from the studies were pooled to calculate the test characteristics for the detection of high-grade squamous intraepithelial lesions (HSIL). 14.1% and 14.2% were positive on testing with VIA and VIAM respectively. Two hundred twenty-nine were diagnosed with HSIL and 68 with invasive cancer. The pooled sensitivity, specificity, positive and negative predictive values for VIA in detecting high-grade squamous intraepithelial lesions (HSIL) were 60.3% (95% CI: 53.6-66.7), 86.8% (95% CI: 86.3-87.3), 5.9% (95% CI: 5.0-7.0), and 99.4% (95% CI: 99.2-99.5), respectively. The values were 64.2% (95% CI: 57.6-70.4), 86.8% (95% CI: 86.2-87.3), 6.3% (95% CI: 5.3-7.3) and 99.4% (95% CI: 99.3-99.6), respectively, for VIAM. Low-level magnification did not improve the test performance of naked eye visualization of acetic acid impregnated uterine cervix.

Guidelines for screening and treatment of cervical disease in the adolescent

BACKGROUND

The last decade has seen a significant increase in our knowledge of HPV infection and its natural history. The advent of liquid-based cytology and HPV testing has changed the way we approach patients with abnormal Pap tests. The objective is to summarize some of the key evidence that lead to the American Society for Colposcopy and Cervical Pathology (ASCCP) guidelines for the management of abnormal cytology and histology and the American Cancer Society (ACS) cervical cancer screening guideline as they pertain to adolescents.

METHODS

The critical publications responsible for the recent ASCCP guidelines as well as the ACS recommendations for cervical cancer screening were reviewed.

RESULTS

Sexually active adolescents are frequently infected by HPV. The natural history of these infections is one with a high rate of resolution. The typical HPV infection will resolve in approximately one year. The ACS has recommended that Pap test screening begin at 21, or 3 years after the onset of sexual activity. The ASCCP guidelines for the management of CIN 1 conclude that observation is the preferred therapy. These recommendations reflect our improved understanding of the natural history of HPV infection.

CONCLUSIONS

Adolescents frequently experience transient HPV infections. As our understanding of the natural history of these infections has improved major national organizations have changed the recommendations for the screening of cervical disease and treatment of low-grade cervical abnormalities. The health care community servicing adolescents should incorporate these recommendations into daily practice.