Acetic acid visualization of the cervix: an alternative to cytologic screening

Safety, acceptability, and feasibility of a single-visit approach to cervical-cancer prevention in rural Thailand: a demonstration project

BACKGROUND

To increase screening and treatment coverage, innovative approaches to cervical-cancer prevention are being investigated in rural Thailand. We assessed the value of a single-visit approach combining visual inspection of the cervix with acetic acid wash (VIA) and cryotherapy.

METHODS

12 trained nurses provided services in mobile (village health centre-based) and static (hospital-based) teams in four districts of Roi-et Province, Thailand. Over 7 months, 5999 women were tested by VIA. If they tested positive, after counselling about the benefits, potential risks, and probable side-effects they were offered cryotherapy. Data measuring safety, acceptability, feasibility, and effort to implement the programme were gathered.

FINDINGS

The VIA test-positive rate was 13.3% (798/5999), and 98.5% (609/618) of those eligible accepted immediate treatment. Overall, 756 women received cryotherapy, 629 (83.2%) of whom returned for their first follow-up visit. No major complications were recorded, and 33 (4.4%) of those treated returned for a perceived problem. Only 17 (2.2%) of the treated women needed clinical management other than reassurance about side-effects. Both VIA and cryotherapy were highly acceptable to the patients (over 95% expressed satisfaction with their experience). At their 1-year visit, the squamocolumnar junction was visible to the nurses, and the VIA test-negative rate was 94.3%.

INTERPRETATION

A single-visit approach with VIA and cryotherapy seems to be safe, acceptable, and feasible in rural Thailand, and is a potentially efficient method of cervical-cancer prevention in such settings.

Use of visual screening methods for cervical cancer screening

This article has considered recent advances in visual screening methods. Devices that use electro-optical sensors offer great potential in various clinical roles, but considerable additional work is required to develop these devices and it is unlikely that they will come into widespread clinical use in the next 5 years. In contrast numerous studies, demonstrate that simple visual screening methods, such as DVI, have a sensitivity for the detection of women with biopsy-confirmed high-grade SIL (CIN 2,3) and cancer that is equivalent to that of conventional cervical cytology. The primary disadvantage of the simple visual screening methods is poor specificity. These methods classify up to 30% of all women screened as being test positive and as a result new strategies toward managing DVI positive women must be developed before simple visual screening methods can be adopted for routine screening. Enhanced visual methods that use cervicography and speculoscopy may be more specific and improve detection of biopsy-confirmed SIL, but the added time and expense to perform either of these methodologies must be considered and justified. Currently numerous studies are evaluating the best strategies for incorporating visual screening methods into cervical cancer screening programs. In the near future we should be able to determine whether these approaches should be incorporated into routine clinical care.

Royal Society of Tropical Medicine and Hygiene meeting at Manson House, London 17 January 2002. Cervical cancer in developing countries

The public health importance of cervical cancer is now increasingly appreciated as a means to improve the general health of women in many developing countries. Developing countries account for 80% of the world burden, mostly due to the lack of effective control programmes. Infection with oncogenic types of human papillomaviruses (HPV) has been established as the central cause for cervical cancer. Thus, vaccination against HPV is a potentially useful strategy for prevention, but this may take several years to become a reality. Currently, early detection and treatment is the most effective approach to control cervical cancer. Cervical cancer may be controlled through improving awareness and accessibility to diagnostic and treatment services. Cytology-based screening is beyond the capacity of health services in many developing countries, hence, alternative methods to cytology are being investigated. Visual inspection of the cervix after application of 3-5% acetic acid (VIA) seems to be a promising screening test, with a similar sensitivity to that of cytology, but lower specificity. Currently, it is being evaluated for its cost-effectiveness in reducing cervical cancer incidence and mortality in randomized trials. Information from the ongoing studies will be valuable for evolving cervical cancer control policies and programmes in low-resource settings.

Direct visual inspection for cervical cancer screening: an analysis of factors influencing test performance

BACKGROUND

The authors evaluated direct visual inspection of the cervix after the application of 5% acetic acid (DVI) as a cervical cancer screening test for use in low-resource settings.

METHODS

Four tests were used to screen 2754 previously unscreened women: DVI with and without x4.5 magnification and differentiating between all lesions and well-circumscribed lesions; testing for high-risk types of human papillomavirus DNA using the Hybrid Capture II assay, cervical cytology, and Cervicography. Women with positive results on any of the four screening tests were referred for colposcopy and histologic sampling. All women were tested for N. gonorrhea, C. trachomatis, T. vaginalis, and human immunodeficiency virus 1.

RESULTS

Histologically confirmed carcinoma was diagnosed in 21 women (0.8%), high-grade squamous intraepithelial lesions (SILs) were diagnosed in 96 women (3.5%), and low-grade SILs were diagnosed in 102 women (3.7%). The estimated sensitivity of DVI when performed without magnification for high-grade SILs was 70%, with an estimated specificity of 79%. Magnification did not significantly improve sensitivity for high-grade SILs (74% with magnification) but significantly reduced specificity (77%). Restricting the definition of a positive DVI test to a well-defined acetowhite lesion reduced sensitivity and significantly improved specificity. Infection with T. vaginalis, N. gonorrhea, and C. trachomatis did not alter sensitivity or specificity.

CONCLUSIONS

This study confirmed the utility of DVI as a primary screening test. Evaluation of the clinical effectiveness of screening with this low-cost and simple test in low-resource settings is necessary.

Shanxi Province Cervical Cancer Screening Study: a cross-sectional comparative trial of multiple techniques to detect cervical neoplasia

OBJECTIVE

The aim of this study was to design a cervical cancer screening algorithm for the developing world that is highly sensitive for cervical intraepithelial neoplasia (CIN) II, III, and cancer and highly specific for CIN II and III, making it possible to ablate the transformation zone without histologic confirmation.

METHODS

In rural Shanxi Province, China, we examined 1997 women ages 35-45. Each subject underwent a self-test for intermediate and high-risk HPV (by HC-II assay), fluorescence spectroscopy, a liquid-based Pap (read manually and by computer and used as a direct test for HPV), a visual inspection (VIA) diagnosis, and colposcopy with multiple cervical biopsies.

RESULTS

Mean age was 39.1 +/- 3.16 years, mean number of births was 2.6 +/- 0.93. Based on tests administered, 4.3% subjects had > or =CIN II. All subjects with > or =CIN II had either a ThinPrep Pap (> or =ASCUS) or a positive HPV direct test. The sensitivity and specificity for the detection of > or =CIN II were, respectively, 83 and 86% for the HPV self-test, 95 and 85% for the HPV direct test, 94 and 78% for the ThinPrep Pap (> or =ASCUS), 77 and 98% for the ThinPrep Pap (> or =HGSIL), 94 and 9% for fluorescence spectroscopy, 71 and 74% for VIA, and 81 and 77% for colposcopy.

CONCLUSION

Based on these data and the existing healthcare infrastructure in China, we believe that further refinement of primary HPV screening using centralized labs is indicated. Self-testing in the local villages may be effective with improvements in the devices and techniques.

Cervical Cancer Screening in Porto Alegre, Brazil: Alternative Methods for Detecting Cancer Precursors in a Developing Country

OBJECTIVE

This study was conducted to test the performance characteristics of cervical cancer screening by visual inspection of the cervix with acetic acid and iodine solution.

METHODS

A total of 100 women were screened for cervical cancer by Pap smear and naked eye inspection of the cervix after application of acetic acid and iodine solution.

RESULTS

Comparing visual inspection to the Pap test, a sensitivity of 85.7%, specificity of 78.5%, and concordance of 79% (p < .0011) was established. Comparing the Pap test with colposcopy, the corresponding figures were 42.9%, 92.3%, and 66.6% (p < .077), respectively. Visual inspection compared to colposcopy showed corresponding figures of 100%, 7.7%, and 55.5% (p = .48), respectively. Colposcopy and biopsy had an agreement of 100%.

CONCLUSIONS

Visual inspection with acetic acid and iodine solution proved to be a reasonable method of screening for cervical cancer precursors.

Adjunctive testing for cervical cancer in low resource settings with visual inspection, HPV, and the Pap smear

OBJECTIVE

To test whether the performance of visual inspection using acetic acid (VIA) could be improved through adjunctive testing and to determine whether the combination of visual inspection of the cervix and HPV testing could prove useful for identifying those at highest risk of cervical precancer.

METHODS

Between October 1995 and August 1997, 2199 women willing to be screened for cervical cancer in peri-urban clinics in Harare, Zimbabwe received VIA, Pap smear and HPV as screening tests. The presence or absence of (pre)cancer was confirmed via colposcopy with biopsy as indicated for >97% of all women. Computerized simulations of sequential testing scenarios provided estimates of the joint (net) test qualities of different paired combinations of the three tests and allowed for comparisons with the individual test qualities.

RESULTS

Using HGSIL/CIN II-III as the reference threshold of disease, the net sensitivity and specificity of VIA and HPV when used sequentially were 63.6 and 81.9%, respectively, compared to 43.3 and 91%, respectively, when Pap smears were followed by HPV testing. VIA followed by the Pap smear yielded a net sensitivity of 37.5% and net specificity of 94.3%.

CONCLUSIONS

For programs with limited resources but with the capacity for HPV testing, sequential testing involving the use of VIA followed by HPV could yield fewer false positives than the use of VIA alone at a cost of relatively few additional false negatives.

Evaluation of alternative methods of cervical cancer screening for resource-poor settings

BACKGROUND

Noncytologic methods of screening for cervical carcinoma and its precursor lesions are needed for resource-poor settings in which cervical carcinoma continues to be an important cause of morbidity and mortality.

METHODS

Two thousand nine hundred forty-four women ages 35-65 years were recruited from Cape Town, South Africa and screened using a combination of a Papanicolaou (Pap) smear, human papillomavirus (HPV) DNA testing, direct visual inspection after the application of a 5% acetic acid solution (DVI), and cervicography. Cervicography was considered primarily as a method with which to quality control the DVI examinations. Women with squamous intraepithelial lesions (SIL) or carcinoma on Pap smear, positive DVI examination (acetowhite lesion or cervical ulcer/growth), high levels of high risk HPV DNA (relative light units [RLU] > 10x positive control), or positive Cervigramtrade mark were referred for colposcopy and cervical biopsy.

RESULTS

Pap smears were positive in 8.1% of all women screened and identified 65 (78%) of all cases of biopsy confirmed high grade disease (high grade SIL or invasive carcinoma). DVI and cervicography were classified as positive in 18.1% and 10.5%, respectively, of women screened and identified 58 (67%) and 46 (58%) of all cases of high grade disease, respectively. The results of HPV DNA testing varied depending on the cutoff value used to define a positive result. At the standard cutoff level (RLU > 1x positive control), 16.2% of women screened were classified as high risk HPV DNA positive, as were 63 women with high grade disease (73%).

CONCLUSIONS

DVI and HPV DNA testing identified similar numbers of high grade SIL (cervical intraepithelial neoplasia Grade 2,3) and invasive carcinoma cases as Pap smears. However, both classify considerably more women without cervical disease as being test positive.

Two-stage cervical cancer screening: an alternative for resource-poor settings

OBJECTIVE

We sought to introduce 2-stage cervical cancer screening in which 2 screening tests are performed sequentially (the second test is performed only if the first result is positive), followed by treatment if both test results are abnormal.

STUDY DESIGN

A total of 1423 women from Cape Town, South Africa, were screened by direct visual inspection, human papillomavirus deoxyribonucleic acid testing, cytologic testing, and cervicography. If an abnormality was identified with any test, women were referred for colposcopy.

RESULTS

Direct visual inspection, cytologic testing, human papillomavirus deoxyribonucleic acid testing, and cervicography, when used alone, identified 24, 26, 23, and 23 cases of disease (high-grade squamous intraepithelial lesion or cancer) per 1000 women, respectively, and would classify 182, 71, 137, and 112 women without disease as having abnormal results. Two-stage screening with direct visual inspection first, followed by cytologic testing, human papillomavirus deoxyribonucleic acid testing, or cervicography, would detect 18, 16, and 18 cases per 1000 women, respectively, and would substantially reduce the number of women without disease who were classified as having abnormal results.

CONCLUSION

Two-stage screening for cervical cancer provides an attractive alternative to conventional screening for low-resource settings.

Evaluation of a human papillomavirus assay in cervical screening in Zimbabwe

OBJECTIVE

To determine the utility of an assay for high risk genital human papillomavirus (HPV) in cervical screening in Zimbabwe, Africa.

DESIGN

Cross-sectional study.

SETTING

Harare, Zimbabwe.

POPULATION

Zimbabwe women (n = 2,140), 25 to 55 years old, recruited in clinics in Chitungwiza and Greater Harare.

METHODS

Genital specimens were assessed for HPV, using the HPV DNA test Hybrid Capture II (probe B). Further assessment of the women was conducted using colposcopy and biopsy as indicated. High grade squamous intraepithelial lesions were diagnosed in 215 women. Colposcopy and/or biopsy showed low grade lesions in 346 women.

RESULTS

The overall prevalences were: 42 x 7% for HPV, 10% for high grade squamous intraepithelial lesions and 16% for low grade lesions. Prevalence for HPV decreased significantly with increase in age (P for trend < 0 x 0001) and increased significantly with increasing disease severity, from 35% in normal women, to 53% in women with low grade lesions and 81% in women with high grade lesions (P for trend < 0 x 001). In specimens positive for HPV, the amount was 14-fold higher in women with high grade lesions compared with normal women. In screening for high grade lesions the assay for HPV had a sensitivity of 81% (CI 75%-86%); sensitivity for low grade lesions was 64% (CI 60%-68%). Specificity was 62% (CI 59%-64%) for high grade lesions and 65% (CI 62%-67%) for low grade lesions. The positive predictive value was 19% (CI 17%-22%) for high grade lesions and 39% (CI 36%-42%) for low grade lesions.

CONCLUSION

For high grade squamous intraepithelial lesions the sensitivity of the Hybrid Capture II HPV DNA test was high, but the specificity was relatively low. The test may therefore be most useful in conjunction with other screening tests.

Visual inspection with acetic acid for cervical-cancer screening: test qualities in a primary-care setting. University of Zimbabwe/JHPIEGO Cervical Cancer Project

BACKGROUND

Naked-eye visual inspection of the cervix with acetic-acid wash (VIA), or cervicoscopy, is an alternative to cytology in screening for cervical cancer in poorly resourced locations. We tested the sensitivity, specificity, and predictive value of VIA done by nurse-midwives in a less-developed country.

METHODS

Women were screened by six trained nurse-midwives in a two-phase, cross-sectional study at 15 primary-care clinics in Zimbabwe. VIA and Pap smears were done concurrently, and their sensitivity and specificity compared. Colposcopy, with biopsy as indicated, was used as the reference test to allow a direct comparison of the test unaffected by verification bias.

FINDINGS

10934 women were screened. In phase II, 2148 (97.5%) of the 2203 participants for whom there was a screening result also had a reference test result. Also in phase II, VIA was more sensitive but less specific than cytology. Sensitivity (95% CI) was 76.7% (70.3-82.3) for VIA and 44.3% (37.3-51.4) for cytology. Specificity was 64.1% (61.9-66.2) for VIA and 90.6% (89.2-91.9) for cytology.

INTERPRETATION

The high sensitivity of VIA shows that the test could be valuable in detection of precancerous lesions of the cervix. However, there are costs to the patient and system costs associated with high numbers of false-positive results, so attention should be given to improving the specificity of VIA.

The Robert Tiffany Lectureship. Vital signs at the millennium: becoming more than we are

Presenting this lecture named for my colleague, the late Robert Tiffany, is an honor. He was part of the first International Conference on Cancer Nursing 20 years ago, which was my first international meeting. It was part of what expanded our Texas--only cancer prevention and detection program for nurses into an international effort. Lessons acquired through this work in the past include learning to respect and honor cultural differences, adapting control programs to the resources at hand, accepting a role as a leader and being an agent for change, and passing on what has been learned to others. The challenges of today include the worldwide death and disability toll of lung cancer, the threat of breast cancer and the promise of regular screening to lower its morbidity and mortality, and the hope that a willingness to adapt screening for cervical cancer in developing countries will lower its mortality rate. Twenty years in the future we can expect nurses to remain educators, exemplars, and agents of change; cancer prevention and early detection to rise in the hierarchy of care; continued collaborative care between physicians and nurses; enhanced patient care through information access; and a larger role for cancer genetics in nursing practice.

Acetic acid improves identification of remnant islands of Barrett's epithelium after endoscopic therapy

BACKGROUND

Instillation of acetic acid onto the uterine cervix at colposcopy has been used for many years to highlight dysplastic areas and thereby enhance the ability to obtain targeted biopsy specimens. As part of an ongoing trial of multipolar electrocoagulation for Barrett's esophagus, we sought to develop a simple technique to identify small islands of residual specialized columnar epithelium after treatment.

METHODS

In 21 consecutive patients, 5 to 10 mL of 1.5% acetic acid was sprayed onto the distal esophagus using a spray catheter, followed immediately by spraying 50 mL of tap water.

RESULTS

Initially, a whitish coloration developed in both esophageal and gastric epithelia. After 2 to 3 minutes, the esophageal squamous mucosa remained white but the columnar epithelium became reddish. Remnant islands of Barrett's epithelium were outlined by a white rim.

CONCLUSION

Acetic acid instillation enhances the ability to detect small or indistinguishable remnant islands of columnar epithelium after endoscopic treatment of Barrett's esophagus. This method is safe, rapid, and inexpensive.