INVASIVE CERVICAL-CARCINOMA - ROLE OF MR-IMAGING IN PRETREATMENT WORK-UP - COST MINIMIZATION AND DIAGNOSTIC EFFICACY ANALYSIS

PURPOSE: To examine the cost and efficacy of diagnostic work-up in pat ients with invasive cervical cancer. MATERIALS AND METHODS: In 246 pat ients with invasive cervical cancer, all diagnostic tests performed be fore treatment were recorded. Patients were divided into two groups: t hose who underwent magnetic resonance (MR) imaging as the initial stud y (n = 105) and those who did not (n = 141). A list of 1995 Medicare g lobal payments was used to measure cost. Bayesian analysis (likelihood ratios derived from a literature search) was performed for bladder, r ectal, parametrial, and nodal involvement in stage Ib disease. RESULTS : Significantly fewer procedures and fewer invasive studies were perfo rmed in the MR imaging group. Net cost savings for the MR imaging grou p was $401 for all patients and $449 for patients with stage Ib diseas e. For stage Ib disease, the 0% pretest probability of bladder or rect al invasion does not justify the routine use of barium enema examinati on, cystoscopy, or proctoscopy. The increase in predictive values for parametrial and nodal disease was highest for MR imaging when tumor si ze was at least 2 cm. CONCLUSION: Guidelines for the pretreatment work -up of clinical stage Ib cervical cancer need revision. MR imaging sho uld be used as an adjunct to clinical evaluation.