DECISION-ANALYSIS FOR BEST MANAGEMENT OF MILDLY DYSKARYOTIC SMEAR

Should a woman with a mildly dyskaryotic cervical smear be referred fo r colposcopy or should the smear be repeated? One way to answer this q uestion is to use decision analysis and compare the expected mortality and cost of each policy. Data for each component of the question were obtained from published work worldwide and were supplemented with an audit of mildly dyskaryotic smears in West Yorkshire, UK. 2 out of 100 0 women with an initial mildly dyskaryotic smear will develop cancer i f a conservative repeat smear policy is adopted in association with fi ve-yearly cervical screening. This number can be reduced to 1.6 per 10 00 if cervical screening is offered every three years. A policy of imm ediate referral for colposcopy is also associated with a subsequent ca ncer rate of 1.6 per 1000. Therefore, repeating the smear is almost as effective as an immediate referral to a colposcopy unit. Even if a fi ve-yearly cervical screening programme is adopted, 2500 women with a m ildly dyskaryotic smear will need to be referred for immediate colposc opy to save 1 additional cancer. A conservative policy is not financia lly cheaper: an average of six additional smears is required to save e ach colposcopy referral. Sensitivity analysis shows that the excess co st of the conservative policy increases exponentially as the risk of a subsequent cytological abnormality exceeds 60%. Local cytopathology l aboratories should audit their recurrent dyskaryosis rate associated w ith borderline, mild, and moderate dyskaryosis before accepting the U- tum in the national recommendations.