Can conventional magnetic resonance imaging, prostate needle biopsy, or their combination predict the laterality of clinically localized prostate cancer?
OBJECTIVE
To evaluate conventional magnetic resonance imaging (MRI), prostate needle biopsy (PBx), and the combination of both tests in predicting the laterality of final specimen pathology after radical prostatectomy.


METHODS
A total of 574 radical prostatectomy cases that had PBx with at least 12 cores and preoperative prostate MRI with pelvic coil were included. We analyzed the clinicopathologic data with laterality based on PBx and MRI. Unilateral disease in combination was defined as unilateral cancer in PBx and at the same time MRI findings of undetectable or ipsilateral disease. Cohen's kappa (κ) was used to measure agreement between the laterality data.


RESULTS
There were a total of 316 (55.1%) unilateral cancers detected by PBx, whereas there were 139 (24.2%) cases in the final specimen pathology. MRI resulted in 119 (20.7%) undetectable and 205 (35.7%) unilateral cancers. Cancer laterality based on final specimen pathology had only fair agreements with PBx (κ = 0.286), MRI (κ = 0.200), and their combination (k = .291). The positive predictive values to predict pathologic concurrent unilaterality were only 30.4% (96/316), 25.9% (53/205), and 34.8% (72/207), respectively. These trends were similar in low-risk cases.


CONCLUSIONS
Preoperative PBx, MRI, and the combination of both methods had only a fair correlation with the laterality of prostate cancer (PC), even in low-risk cases. Approximately two thirds of cases diagnosed as unilateral disease by contemporary PBx, MRI, or their combination were not concurrent unilateral disease in final pathology. This should be recognized when planning nerve-sparing surgery and potentially for candidate selection for focal therapy to treat PC.
Department of Urology, College of Medicine, Seoul National University, Seoul, Korea.
Chang Wook
CW
Jeong
Ja Hyeon
JH
Ku
Kyung Chul
KC
Moon
Sung Kyu
SK
Hong
Seok-Soo
SS
Byun
Jeong Yeon
JY
Cho
Hyeon Hoe
HH
Kim
Seung Hyup
SH
Kim
Sang Eun
SE
Lee
Cheol
C
Kwak
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001707:Biopsy, Needle; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D057234:Preoperative Period; D011471:Prostatic Neoplasms / Q000473:pathology* / Q000601:surgery; D012189:Retrospective Studies