Cervical Cancer Screening by Simple Visual Inspection After Acetic Acid
Abstract & Commentary
Synopsis: In developing countries, visual inspection of the cervix after acetic acid application may prove to be a useful screening test for neoplasia.
Source: Belinson JL, et al. Obstet Gynecol. 2001;98: 441-447.
In many areas of the world, cervical cancer remains a common malignancy of adult women. Unfortunately, many developing countries cannot afford the cost of cytology screening programs, colposcopic triage, and subsequent therapy for preinvasive disease. One strategy that is being developed for cancer screening in these areas is the visual inspection of the uterine cervix after the application of acetic acid. Several preliminary articles have suggested that the technique may have sufficient sensitivity and specificity to be useful.
This study was performed in the Shanxi Province of China in 1997. A total of 1997 women were screened. All had a cervical speculum placed, 5% acetic acid applied to the cervix, and visual inspection of the cervix performed 1 minute later. The visual inspection results were reported as normal, low-grade, high-grade, or cancer. Following this inspection, physicians who had not performed the visual inspection performed a colposcopic evaluation. Abnormal areas were biopsied as well as at least 1 biopsy from each quadrant of the cervix, and an endocervical curettage.
As would be expected, most women in the study had normal visual inspection and normal biopsies. Of these, 552 (28%) had visual abnormalities; 27 were visually either high-grade lesions or cancer.
The biopsies identified 86 women with CIN II or greater lesions. When all women with any visual abnormality (low-grade, high-grade, or cancer) were considered as a group, 61 of 86 CIN II or greater lesions were identified. The positive predictive value in these 552 women with any abnormality was 11%.
Belinson and associates suggest that visual inspection of the cervix may be a legitimate technique for screening in developing countries as it requires very few supplies and low cost. The training is simple. Diagnosis and treatment can be achieved at the time of a single visit.
Comment by Kenneth L. Noller, MD
The reason I chose this article was to make our readers aware of the fact that visual inspection of the cervix after the application of acetic acid is becoming an accepted technique for cervical cancer screening in developing countries. My first introduction to the technique was at an international conference on cervical cancer screening that I attended several years ago. The conference was very enlightening and opened my eyes to an entirely different way of thinking about such screening. In the United States, as we all know, virtually nothing less than complete identification of every significant cervical neoplasia is required. However, such precision comes at quite a price. When one considers the cost of a Pap smear and office visit (even without considering such things as lost time from work, transportation, and child care), an annual Pap smear may easily cost $100. In developing countries, Pap smear screening costs must be held to a minimum, and several developing countries have reported total screening costs of less than $0.25 per individual. While these inexpensive techniques (such as visual inspection) do not identify all significant disease, they are "good enough" to identify most cases and should ultimately be shown to decrease the incidence of cervical cancer.
I do have some concerns with some of the results and conclusions in this paper. While visual inspection was able to identify 71% of the biopsy-positive cases of CIN II or greater, this was only accomplished when all 552 women with low-grade or more changes were biopsied. That is, 28% of the screened population had some changes that would require either referral for colposcopy, random biopsy, or immediate treatment. If all were treated, about 90% would have no disease or minimal disease. Additionally, visual inspection only suspected invasive cancer in 6 women, 3 of whom had the disease. Three other patients were in the high-grade group and 2 hidden among those with low-grade changes. Four of the 12 cases would have been missed.
I strongly suspect that visual inspection will ultimately become a common technique for the detection of cervical neoplasia in developing countries. While a few women with significant lesions will be missed, the majority should be identified. In many parts of the world, this may be acceptable—at least at the present time.