Today there are no established techniques to image positive surgical margins (PSM) intraoperatively in
endoscopic extraperitoneal radical prostatectomy (EERPE). The intention of this study was to describe the
specific technique of photodynamic diagnosis (PDD) in patients undergoing EERPE and report on the potential
to detect PSM under PDD.
Materials and Methods: Twenty-four patients with clinically organ-confined prostate cancer received 5-
aminolevulinic acid 20mg=kg body weight orally 3 hours prior to nonnerve-sparing EERPE. An endoscopic PDD
system (Karl Storz, Tuttlingen, Germany) including a TricamPDD3-chip camera head linked with a straight 10-mm
telescope and a D-light C system was used. During EERPE, visualization of the surgical margins was performed by
means of both white light and PDD at specific steps during standardized prostatectomy in all patients. Positive
PDD areas on the prostate specimen were marked with white ink and consequently processed in pathology.
Results: In white light endoscopy, no suspicion of a PSM was raised. Six out of the eight PSM were detected by
PDD. In two cases, areas of positive PDD findings were free of prostate cancer and two PSM were not detected
by PDD ( one bladder neck, one lateral). The overall sensitivity and specificity were 75% and 88.2%, respectively.
Conclusions: Laparoscopy offers an appropriate setting for the use of PDD in prostate cancer to visualize
possible PSM. Although imaging of PSM by PDD is promising with the technique being feasible and safe, larger
series are needed to prove the reproducibility of our results.