[The value of transrectal MRI in the staging of localized prostate cancer].
OBJECTIVE
To determine the diagnostic value of transrectal magnetic resonance imaging (MRI) in the local staging of prostatic cancer.


METHODS
75 patients suffering from clinically localized prostatic cancer were included consecutively from December 1992 to September 1996. An MRI examination (1.5 Tesla, Siemens) with a transrectal coil was performed before radical prostatectomy. The results of this examination in terms of capsular invasion, seminal vesicle lesion and apical invasion were correlated with the results of histological examination of the operative specimen and the findings of digital rectal examination, transrectal ultrasonography, serum PSA level and biopsy mapping.


RESULTS
The best performance of transrectal MRI concerned elimination of seminal vesicle lesion with a specificity of 92%. The positive predictive value of transrectal MRI was 90% for the capsular invasion. The positive predictive value of transrectal MRI was 56% for the apex, the sensitivity was 40% and the specificity was 82%. When transrectal MRI did not reveal any extraprostatic involvement the risk of positive margins on radical prostatectomy was less than 6%.


CONCLUSIONS
In this study, transrectal MRI appeared to be satisfactory to improve the staging of localized prostate cancer, especially in terms of seminal vesicle lesion and apical invasion, but, most importantly, appeared to be very useful to predict negative resection margins.
Pariente
J L
JL
Service d'Urologie et de Transplantation rénale, CHU de Bordeaux, France.
Jacob
F
F
Trillaud
H
H
Deminiere
C
C
Khan
H
H
Ferrière
J M
JM
Grenier
N
N
Le Guillou
M
M
D000368:Aged; D014408:Biomarkers, Tumor / Q000097:blood; D001706:Biopsy; D003949:Diagnostic Techniques, Surgical; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging; D010808:Physical Examination; D011237:Predictive Value of Tests; D011300:Preoperative Care; D017430:Prostate-Specific Antigen / Q000097:blood; D011468:Prostatectomy; D011471:Prostatic Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D012007:Rectum; D012307:Risk Factors; D012669:Seminal Vesicles / Q000473:pathology; D012680:Sensitivity and Specificity; D014463:Ultrasonography
D014408:Biomarkers, Tumor; D017430:Prostate-Specific Antigen