Is cervical cancer screening necessary or the "Paradox" example of Bulgaria

The present study aimed at analyzing the results of cervical screening carried out in Bulgaria, its effect on basic epidemiological indices, age-related incidence of cervical cancer and their dynamics. It also highlighted the way in which the suspension of organized screening has influenced the epidemiological data for cervical cancer.

Analyses were carried out, based on data from the National Cancer Register, the Central Institute of Statistics and the Oncological Dispensaries. Simple mathematical methods were used to analyze the attendance rate, the rate of inadequate smears and share of biopsies in women with abnormal cytology. Cohort analysis was utilized in determining age-specific incidence.

Incidence and mortality were stable during the first 15 years of screening activities, followed by a constant increase which became most obvious after the final interruption of organized screening. The ratio between invasive cancer and carcinoma in situ ranged from 2:1 in 1982 to over 5:1 in 2002 and was due to the faster increasing rates of invasive cancer. Age groups' and birth-cohort analysis for 3 time points (1975, 1990, and 2005) with different screening characteristics showed highest incidence in middle-aged women and a higher risk of cervical cancer for every subsequent generation.

Bulgaria gives yet another, though "paradoxical", example in support of the importance of organized cervical screening. This conclusion has been reinforced by a distinct deterioration of epidemiological characteristics of cervical cancer in our country as a result of absence of an organized screening. This serious situation lends valid reasons to recommend that the relevant health authorities take a political decision to launch a programme in compliance with the European standards.