Evaluation of downstaging in the detection of cervical neoplasia in Kolkata, India

Abstract

Unaided visual inspection or "downstaging" has been suggested as a potential alternative method for cervical cancer screening in developing countries. Our study was designed to evaluate the accuracy of downstaging to detect cervical neoplasia in a low-resource setting. A total of 6,399 women aged 30 -64 years were screened with downstaging by trained nonmedical health workers. Two thresholds were used to define positive downstaging: "low threshold" when any visible abnormality on the cervix was considered positive and "high threshold" when selected abnormalities such as bleeding on touch, bleeding erosion, hypertrophied oedematous cervix, congested stippled cervix and growth or ulcer constituted the positive test. All women underwent a colposcopy examination. Biopsies were directed when colposcopy revealed abnormal lesions. True disease status was defined as histologically proven moderate dysplasia and worse lesions. Since all the participants received a diagnostic (reference) investigation (biopsy and/or colposcopy), sensitivity, specificity and predictive values were estimated directly. Low-and high-threshold downstaging were positive in 1,585 (24.8%) and 460 (7.2%) women, respectively. Cytology screening for cervical cancer has been successful in reducing the incidence of and mortality from cervical cancer in many developed countries. 1-3 On the other hand, cervical cancer incidence and mortality rates have either remained unchanged or slowly declined in many low-resource developing countries. 4 -7 The primary reason for this is that most of these countries and regions lack effective cervical cancer screening programmes. Some of them have implemented cytology-based screening programmes nationally or regionally that have had very little impact on the incidence and mortality from cervical cancer. 7-9 The prerequisites for the success of cytology-based screening programmes are high coverage of the target population, preparation of goodquality cytology smears, well-equipped laboratory service with internal and external quality-control measures, adequate numbers of well-trained technical personnel, stringent quality assurance, efficient referral system and treatment and follow-up of those with precursor lesions, most of which are not feasible in underdeveloped countries. Therefore, the need for a relatively inexpensive and low-technology alternative to detect cervical neoplasia in low-resource settings has long been felt.Naked-eye visualization of the cervix (without application of acetic acid) by trained health workers has been considered as an option for low-resource countries to detect cervical cancer early and to improve the survival from the disease. 10,11 This approach, known as downstaging or unaided visual inspection (UVI), has been defined as "the detection of the disease in an earlier stage when still curable, by nurses and other nonmedical health workers using a speculum for visual inspection of the cervix". 11Here we report the findings from a cross-sectional study that evaluated the performance of d...

Early detection of cervical cancer with visual inspection methods: a summary of completed and on-going studies in India

“…[8][9][10][11][12][13][14][15] Seven of these studies allow estimation of test characteristics. [9][10][11][12][13][14][15] However, six of the studies used cervical cytology as the 'reference investigation' or 'gold standard' to assess the test performance to detect cervical dysplasias and invasive cancer. [9][10][11][12][13][14] The proportion of women subjected to colposcopy and histology was very low in these studies.…”

“…16,17 The findings and deficiencies of the Indian studies using cytology as reference investigation have been extensively reviewed. 15,18 Of particular interest in assessing the performance of downstaging is a recently reported cross-sectional study from Calcutta, India, in which 6 399 women aged 30 to 64 years were screened with downstaging by trained workers. 15 Two thresholds were used to define positive downstaging: 'low threshold' when any visible abnormality on the cervix was considered positive and 'high threshold' when selected abnormalities such as bleeding on touch, bleeding erosion, hypertrophied oedematous cervix, congested stippled cervix and growth or ulcer constituted the positive test.…”

Comparison of Methods of Visual Inspection of Cervix With Cervical Cytology in Detection of Pre-Invasive Lesions of Cervical Cancer

“…4 A quarter of burden is experienced in India, where 1,26,000 new cases and 71,000 deaths attributable to cervical cancer annually. Cervical cancer is a potentially preventable cancer.…”

Performance characteristics of visualising the cervix in symptomatic young females: a review of primary care records in females with and without cervical cancer

“…A study of asymptomatic females aged 30-64 years invited to attend an early-detection clinic in India found that unaided visual inspection detected between 7.2% and 24.8% of cervical cancers. 6 In a study of urgent referrals for a clinically suspicious cervix to a colposcopy clinic in Aberdeen (Aberdeen Royal Infirmary), only 4% (4 out of 104) of females were found to have cervical cancer.14 In a similar but smaller audit of a colposcopy clinic in London (Whipps Cross University Hospital), only one female was found to have cervical cancer out of 25 who were referred with a clinically suspicious cervix.15 These poor conversion rates for referrals with a clinically suspicious cervix support the present findings and assertion that (unaided) visual inspection is largely inefficient at detecting cancer.Implications for research and practice NICE guidelines in England recommend that urgent referral should be considered if the cervix appears to be consistent with malignancy.2 The present findings suggest that visual inspection of the cervix is inefficient at detecting cervical cancer. This highlights the need for additional triage tools for primary care physicians managing young females with gynaecological symptoms.…”