Factors Affecting Non-Histologically Proven Invasive Cancer of the Uterine Cervix that Had an Abnormal Pap Smear: Results of the CCS Program

Abstract

Background: Cervical cancer (CC) ranks fourth among cancers diagnosed around the world, but early detection and treatment can reduce invasive cervical cancer and mortality. Screening programs (CCSP), such as the one covering Thailand’s 75 provinces, use histology to confirm cases. The study determined the incidence rate (IR) and investigated the factors associated with non-histologically proven invasive cancer of the uterine cervix (non-HPICUC) with an abnormal pap smear from the CCSP at Mahasarakham Hospital, Thailand. Methods: The CCSP was used to analyse a retrospective cohort of 288 women between 30 and 60 years of age. All abnormal pap smears were followed up until April 30, 2022. We estimated the IR and assessed the relationship between various independent variables and non-HPICUC using the generalised linear model (GLM) for testing association data. We reported the adjusted RR and 95% confidence intervals (95%CI). Results: 260 non-HPICUC cases had abnormal CCSP pap smears for an overall IR of 90.0 (95% CI: 86.3 - 93.2). After adjusting the model for all variables, age at recruitment and pregnancy had a statistically significant association with non-HPICUC (p-value < 0.05). We found that the risk of non-HPICUC increased 1.02 times for every 20-year increment in age compared to below that age (adjusted RR=1.02, 95% CI: 1.01 - 1.04). Pregnancy at risk for non-HPICUC was 0.89 times compared to non-pregnancy (adjusted RR=0.89, 95% CI: 0.80 - 0.99). Pathological vaginal discharge (PVD) did not have a statistically significant association with non-HPICUC (p-value = 0.094); notwithstanding, women with PVD had 1.08 times the risk of non-HPICUC compared to women without PVD (adjusted RR=1.08, 95% CI: 0.97 - 1.20). Conclusions: Based on an abnormal pap smear from the CCS Program at Mahasarakham Hospital Thailand, age and pregnancy are associated with an increased risk of non-HPICUC. High-risk groups with abnormal pap smears should be targeted for CC campaigns.