BACKGROUND : The tumor volume is thought to be one of the most important prognostic factors in cervical cancer therapy. There are several methods for the estimation of the tumor volume of cervical cancer such as pelvic examination, colposcopy, conventional ultrasonography(2D USG) and CT/MRI. Three- dimensional ultrasonography(3D USG) has been applied recently into clinical application for volume estimation, and digital documentation of whole volumes enables full evaluation with accurate sections and suitable views needed for diagnosis and geometric measurements. OBJECT IVE : To compare the accuracy of the 3D USG in volume estimation of cervical cancer with 2D USG and MRI. MAT ERIALS AND MET HODS : From March to September 1998, we have examined 10 patients with cervical cancer of stage Ib-IIa scheduled for radical hysterectomy and pelvic lymphadenectomy. For the evaluation of accuracy of 2D USG, 3D USG and MRI in the assessment of volume of cervical cancer, we compared the results of each methods with those of surgical specimen measured by pathologist respectively. RESULT S : A total of 10 cases, 7 with exophytic tumors and 3 with endophytic tumors, were enrolled in this study. The mean tumor volume and standard deviation was 12.5 ml/ 18.18 by surgical specimen, 10.9 ml/ 9.59 by 2D USG, 9.8 ml/9.72 by 3D USG and 14.6 ml/ 15.81 by MRI. The mean differences and standard deviation with the volume of surgical specimen were +1.60/ 13.36 for 2D USG, +2.70/ 13.17 for 3D USG, and -2.10/ 7.11 for MRI. The limits of agreement with 95% confidence interval between the volume measured from surgical specimen and tumor volume determined by three methods were -7.96 to +11.16 for 2D USG, -6.72 to +12.12 for 3D USG and -7.19 to +2.99 for MRI. With paired t-test and Wilcoxon signed ranks test, all the 3 methods of volume assessment were not significantly different from that of surgical specimen(p > 0.05). CONC LU S ION : There was no significant difference in the accuracy of the estimation of true volume in cervical cancer among three methods, and for the exact evaluation of the accuracy, sufficiently large scaled study should be performed. The analysis about cost-effectiveness also should be performed to evaluate the final efficacy of each method at an acceptable financial cost.

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