[Volume determinations of the whole prostate and of the adenoma by transrectal ultrasound: correlation with surgical specimen].
OBJECTIVE
We evaluated whether preoperative transrecta ultrasound (TRUS) mesaurements of the transition zone (TZ) and total prostate volumen predict real prostatic weight.


METHODS
We compare estimated TRUS volumes with surgical specimen weight, in surgically treated patients with localized prostate cancer (group A, n = 33) or benign prostatic hyperplasia (group B, n = 37). The volume was calculated by the ellipsoid formula. Both measurements were compared with surgical specimen weight, assuming 1 as specific prostate weight.


RESULTS
Group A: mean prostate measured volume was 38.6 cc. (SD 22.7), mean RP specimen weight was 54,2 g (SD 27.2) (p = 0.001). Total estimated prostate volume underestimated prostatectomy specimen weight by 29%. In order to adequate the estimated volume to the specimen weight, we calculated the formula: estimated prostate weight = 0.95 x prostatic measured volume + 17,657 (p = 0.005). Group B: mean TZ measured volume was 62.8 cc. (SD 23.3), mean adenomectomy specimen weight was 79.9 g (SD 45.9) (p = 0.001). TZ estimated volume underestimated adenomectomy specimen weight by 21%. In order to adequate the estimated volume to the specimen weight, we calculated the formula: estimated TZ weight = 1.67 x TZ measured volume - 24,768 (p = 0.04).


CONCLUSIONS
We found significative differences between TRUS measured volumes and real weight of surgical specimen. These differences could be corrected by simple formulas that allow to minimize the observed underestimations.
Cabello Benavente
R
R
Servicio de Urología, Hospital General Universitario, Gregorio Marañón, Madrid. ramirocabello@telefonica.net
Jara Rascón
J
J
Monzó
J I
JI
López Díez
I
I
Subirá Ríos
D
D
Lledó García
E
E
Herranz Amo
F
F
Hernández Fernández
C
C
D000368:Aged; D006801:Humans; D008297:Male; D009929:Organ Size; D011470:Prostatic Hyperplasia / Q000000981:diagnostic imaging* / Q000473:pathology* / Q000601:surgery; D011471:Prostatic Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology* / Q000601:surgery; D012007:Rectum; D012189:Retrospective Studies; D014463:Ultrasonography / Q000379:methods