RESUMEN
This retrospective cohort study focused on colposcopic accuracy for the diagnosis of cervical premalignant lesions using cytology and histology, as well as HPV data not included in current cervical screening practices in Kazakhstan. Colposcopy performance was assessed using the modified Reid index in women aged 18-63 years. In total, 1,129 colposcopic-HPV-cytology triple samples and 94 histology findings were collected. The sensitivity of colposcopy was 81.6% with specificity 72.6% for LSIL but fell to 56.6% with specificity 88.3% for CIN2+ vs. 89.6% and 74.5% for cytology at CIN2+, respectively. The ORs for high-grade lesion occurrence within each colposcopy group at viral load rising vs. ORs for HPV-negative women were 3.4; 5.3; and 39.7, respectively (p < 0.0001). Total attributive agreement between the colposcopy and histology findings reached 55.3%, κ 0.47 ± 0.06 vs. 0.62 ± 0.08 for cytology, and 0.34 ± 0.13 and 0.58 ± 0.1, for specialists, respectively. Outcomes obtained for colposcopy alone failed to show satisfactory reliability. Globally adopted primary HPV screening would be the best option despite the related costs.
RESUMEN
OBJECTIVE: To assess the effectiveness of the current cervical cancer screening tools in Western Kazakhstan. METHODS: Smears taken through (i) conventional cytology using azur-eosin staining and (ii) liquid-based cytology (LBC) 'Cell Scan' in the general female population and in women first diagnosed with cervical cancer were collected throughout the region. ROC-analysis with curve construction and weighted Cohen's κ calculation were applied. A total of 494 cytological pairs were collected, including 94 sets with histology findings. RESULTS: The conventional (azur-eosin staining) technique contained 0.2% non-informative material and LBC 'Cell Scan' had 5.9%. Area under the curve was 0.95 for the conventional technique and 0.92 for 'Cell Scan' (p > 0.05). The conventional smears showed κ 0.62, sensitivity 90.4% at specificity 90.0% for CIN2+, while LBC 'Cell Scan' smears showed κ 0.47, sensitivity 83.3% at specificity 92.5%. CONCLUSIONS: In this analysis it was not possible to prove that the LBC 'Cell Scan' technique was superior to its predecessor, azur-eosin staining. These findings highlight the need to modify the current screening programme according to updated international scientific evidence on effective screening design, such as the use of HPV DNA testing with Pap smear triage in women aged 30 or older. Further research, and a Health Technology Assessment, are necessary if we wish to establish a national standardized screening programme using the available technology appropriately.