Magnetic resonance tomography and endosonography in the preoperative staging of advanced rectal carcinomas after hyperthermoradiochemotherapy

Abstract

Comparison of diagnostic accuracy of staging of endorectal sonography (ES) and body coil MRI after preoperative hyperthermoradiochemotherapy in patients with advanced rectal cancer. Prospective analysis of MRI and ES in 30 patients after hyperthermoradiochemotherapy and correlation with histopathological patterns. T-staging by MRI was correct in 47% and by ES in 53% of the cases. Despite similar accuracy of staging in T0- and T1-tumours, we found different accuracies concerning T2-tumour staging about 63% versus 73% (MRI/ES), concerning perirectal infiltration 70% for both techniques, concerning invasion of adjacent organs 90% versus 87%, and concerning lymph node metastases without respect to the N-stage 63% versus 63%. Both imaging modalities provide useful information for operation planning despite limited accuracy after hyperthermoradiochemotherapy. The body coil MRI does not seem to be severely inferior to ES in post-therapeutic staging, despite better contour line imaging by ES. With respect to the determination of invasion of other organs, MRI seems to be more useful.