This study aims to determine whether nerve-sparing radical prostatectomy defined
by surgical intent or pathological presence of neurovascular bundle is associated
with a higher positive surgical margin rate.
Seventy consecutive patients who underwent radical prostatectomy from October
2014 to June 2017 at our institution were included in this study. Clinico-pathological
data were extracted from medical records. Pathology slides were reviewed by a
single pathologist for presence of neurovascular bundle (defined by extra-capsular
nerve size >200um), and extra-capsular nerve invasion. Statistical analysis was
performed using Chi-square test.
The median age of patients was 64, and the median PSA was 8. 4.3% of patients had
ISUP 1, 55.7% ISUP 2, 21.4% ISUP 3, 10% ISUP 4, and 8.6% ISUP 5 disease. Based on
surgical intent, 32.9% of patients had bilateral nerve spared, 10% had unilateral
nerve spared, and 57.1% had non-nerve sparing procedure. Positive margin rate was
not statistically different, with a rate of 20% (n=6/30) in nerve sparing and 32.5%
(n=13/40) in non-nerve sparing procedures. Based on pathological presence of
neurovascular bundle, 17.1% had bilateral nerve spared, 34.3% had unilateral nerve
spared, and 48.6% had non-nerve sparing procedure. Positive margin rate was not
statistically different, with a rate of 22.2% (n=8/36) in nerve sparing and 32.4%
(n=11/34) in non-nerve sparing procedures. Overall, 12.8% of patients had extra-
capsular nerve invasion, and only 2.9% had invasion of neurovascular bundle.
Nerve-sparing radical prostatectomy is not associated with a higher positive surgical
margin rate. Neurovascular bundle involvement by tumour is rare.