Greetje Groenendaal1, Maaike R. Moman1, Johannes G. Korporaal1, Paul J. van Diest2, Marco van Vulpen1, Marielle E.P. Philippens1, Uulke A. van der Heide1
1Radiotherapy, University Medical Center Utrecht, Utrecht, Netherlands; 2Pathology, University Medical Center Utrecht, Utrecht, Netherlands
Sensitivity and specificity values of DW-MRI and DCE-MRI for prostate cancer are often based on the correspondence of imaging and pathology within relatively large volumes inside the prostate. However, for prognosis, therapy selection and focal therapy, decisions on a voxel level are required. We investigated at which spatial resolution validation of MR images with hematoxylin-eosin stained sections is meaningful. We found that the chance is small that matching tumor voxels are found on the MR images and pathology within a volume smaller than 0.4 cc. This puts limitations on the accuracy at which tumor volume and extent can be determined.