Tumorsize dependent detection rate of endorectal MRI of prostate cancer--a histopathologic correlation with whole-mount sections in 70 patients with prostate cancer.
OBJECTIVE
To evaluate the value of T2w endorectal MRI (eMRI) for correct detection of tumor foci within the prostate regarding tumor size.


METHODS
70 patients with histologically proven prostate cancer were examined with T2w eMRI before radical prostatectomy at a 1.5T scanner. For evaluation of eMRI, two radiologists evaluated each tumor focus within the gland. After radical prostatectomy, the prostates were prepared as whole-mount sections, according to transversal T2w eMRI. For each slice, tumor surroundings were marked and compared with eMRI. Based on whole-mount section, 315 slices were evaluated and 533 tumor lesions were documented.


RESULTS
Based on the T2w eMRI, 213 tumor lesions were described. In 137/213, histology could prove these lesions. EMRI was able to visualize 0/56 lesions with a maximum size of <0.3 cm (detection rate 0%), between 0.3 and 0.5 cm 4/116 (3%), between 1 and 0.5 cm 22/169 (13%), between 2 and 1cm 61/136 (45%) and for >2 cm 50/56 (89%). False positive eMRI findings were: <0.3 cm n=0, 0.5-0.3 cm n=12, 0.5-1cm n=34, 1-2 cm n=28 and >2 cm n=2.


CONCLUSIONS
T2w eMRI cannot exclude prostate cancer with lesions smaller 10mm and 0.4 cm(3) respectively. The detection rate for lesions more than 20mm (1.6 cm(3)) is to be considered as high.
Roethke
Matthias C
MC
Department of Diagnostic and Interventional Radiology, University of Tuebingen, Hoppe-Seyler-Str. 3, 72076 Tuebingen, Germany. Matthias.roethke@med.uni-tuebingen.de
Lichy
Matthias P
MP
Jurgschat
Leo
L
Hennenlotter
Jörg
J
Vogel
Ulrich
U
Schilling
David
D
Stenzl
Arnulf
A
Claussen
Claus D
CD
Schlemmer
Heinz-Peter
HP
D001706:Biopsy; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011468:Prostatectomy; D011471:Prostatic Neoplasms / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery; D012007:Rectum; D012680:Sensitivity and Specificity