Local staging of prostate cancer by endorectal MRI using fast spin-echo sequences: prospective correlation with pathological findings after radical prostatectomy.
OBJECTIVE
To evaluate the accuracy of endorectal magnetic resonance imaging (MRI) with fast spin-echo sequences in the local staging of clinically localized prostate cancer.


METHODS
Seventy-one patients with a clinical T1 (18 patients) or T2 tumour (53 patients) underwent endorectal MRI 2-12 weeks before radical prostatectomy. Extraprostatic tumour was diagnosed if MRI showed signs of capsular penetration and/or invasion of the seminal vesicle and/or distal urethra or bladder neck. If the pathological examination showed a single positive margin with no periprostatic tissue, the tumour was classified as indeterminate and not as a T3 tumour.


RESULTS
Of the 25 cases of capsular penetration. MRI correctly identified 10 (sensitivity 42%, specificity 100%). Of the 14 cases with seminal vesicle invasion, MRI correctly identified six (sensitivity 43%, specificity 100%), but showed other signs of extraprostatic tumour spread in seven of the eight unidentified cases. Overall, MRI identified 16 of the 30 patients (53%) with occult extraprostatic spread of tumour; there was only one false-positive result. The sensitivity, specificity and accuracy of MRI were 53, 96 and 74%, respectively.


CONCLUSIONS
Endorectal MRI can reduce the rate of preoperative understaging from 42% to 22% and it can be used for a given individual because it can detect extraprostatic invasion with 96% specificity, ensuring that very few, if any, patients will be deprived of curative surgery.
Cornud
F
F
Service d'Urologie, Hôpital Necker, Paris, France.
Belin
X
X
Flam
T
T
Chrétien
Y
Y
Deslignieres
S
S
Paraf
F
F
Casanova
J M
JM
Thiounn
N
N
Hélénon
O
O
Debré
B
B
Dufour
B
B
Moreau
J F
JF
D000368:Aged; D005834:Genital Neoplasms, Male / Q000473:pathology; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging / Q000379:methods*; D011446:Prospective Studies; D011468:Prostatectomy; D011471:Prostatic Neoplasms / Q000473:pathology* / Q000601:surgery; D012669:Seminal Vesicles; D012680:Sensitivity and Specificity; D014523:Urethral Neoplasms / Q000473:pathology; D001749:Urinary Bladder Neoplasms / Q000473:pathology