Preoperative renal tumor evaluation by three-dimensional magnetic resonance imaging: Staging and detection of multifocality.
OBJECTIVE
To evaluate, retrospectively, the staging accuracy of three-dimensional magnetic resonance imaging (3D-MRI) in our institution as a prelude to a prospective comparison of 3D-MRI and 3D computed tomography (CT) for preoperative planning of partial nephrectomy. In recent years, the use of 3D-CT for preoperative evaluation and surgical planning in patients undergoing nephron-sparing surgery has gained considerable popularity.


METHODS
The images of 26 consecutive patients evaluated by 3D-MRI as part of the preoperative imaging studies for renal tumor were evaluated retrospectively and compared with the surgical pathologic findings to evaluate the ability of 3D-MRI to predict tumor multifocality, tumor stage, collecting system invasion, and venous invasion.


RESULTS
3D-MRI accurately predicted tumor multifocality in 1 of 2 cases. Imaging identified five of seven multifocal lesions. Two subcentimeter lesions were missed. Preoperative staging was correct in 29 of 30 lesions (97% accuracy). One T3b tumor was incorrectly staged as T2. Venous invasion was identified in 2 of 3 cases (67% sensitivity), but no false-positive results were seen. 3D-MRI had 100% sensitivity and 88% specificity in the prediction of collecting system invasion.


CONCLUSIONS
The staging accuracy of 3D-MRI appears to be quite good. Given the accuracy of this technique, along with the popularity of 3D imaging before renal surgery, these results provide the impetus for a future study directly comparing 3D-CT with 3D-MRI in the capacity of surgical preoperative planning.
Huang
George J
GJ
Department of Urology, New York University School of Medicine, New York, New York 10016, USA.
Israel
Gary
G
Berman
Adam
A
Taneja
Samir S
SS
D002291:Carcinoma, Papillary / Q000473:pathology / Q000601:surgery; D003287:Contrast Media; D005189:False Positive Reactions; D005682:Gadolinium; D006801:Humans; D021621:Imaging, Three-Dimensional; D007680:Kidney Neoplasms / Q000473:pathology / Q000601:surgery*; D008279:Magnetic Resonance Imaging; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging / Q000379:methods; D009392:Nephrectomy / Q000379:methods*; D011300:Preoperative Care; D012082:Renal Veins / Q000473:pathology; D012189:Retrospective Studies; D016037:Single-Blind Method
D003287:Contrast Media; D005682:Gadolinium