Presidential Greeting - American Society for Laser Medicine and ...

preserved and denaturated, inducing fibroblast activation and
collagen neoformation.
#187
TREATMENT PLANNING OPTIMIZATION OF
PHOTODYNAMIC THERAPY OF PROSTATE
CANCER USING WST11-TOOKAD SOLUBLE
Nacim Betrouni, Renaud Lopes,
Marqa Mohamad-Feras, Pierre Colin,
Pierre Nevoux, Serge Mordon
INSERM U703, Lille, France
Background: Interstitial photodynamic therapy (iPDT) appears
as a promising technique to treat some early stage prostate
tumours. Traditionally drugs target the cellular compartments to
destroy a tumour but newer vascular-targeting (VT)
photosensitizers as WST11 are activated while in vasculature.
This property is exploited to cause vascular damage and to
enhance tissue necrosis. In this study we were interested by the
dosimetric planning of iPDT of prostate cancer using WST11.
Study: Retrospective analysis was executed using results from 28
patients enrolled in phase II trials of VTiPDT with the WST11
drug. An optimised action radius was determined using the
following parameters of: (i) 4 mg/kg drug dose of, (ii) 200 J/cm light
dose, (iii) devascularised volume, measured after swelling
correction, on the D7 MR images. Treatment planning is then
performed, based on this optimal radius, by optimising the fibres
number, their lengths and their positions using the Powell
algorithm.
Results: Validation of the method carried out on six patients
indicated that the software is able to predict the final damage with
an overlap of at least 84% corresponding to a margin of less than
2 mm.
Conclusion: The proposed model and treatment planning
method allow realistic simulation of the iPDT results. They are
not based on light dose distribution analysis through the
evaluation of the prostate optical properties but are based on a
correlation between the two main factors influencing the therapy:
drug and light doses.
#188
American Society for Laser Medicine and Surgery Abstracts 55
THE 180 W GREENLIGHT XPS—LASER
PHOTOSELECTIVE VAPORIZATION
PROSTATECTOMY FOR SYMPTOMATIC BENIGN
PROSTATIC HYPERPLASIA: PRELIMINARY
RESULTS
Kurt Strom, Xiao Gu, Massimiliano Spaliviero,
Carson Wong
The University of Oklahoma Health Sciences Center,
Oklahoma City, OK
Background: GreenLight XPS TM laser PVP is a recently
approved treatment option for lower urinary tract symptoms
(LUTS) secondary to BPH. We review our perioperative
experience using the GreenLight XPS TM laser system.
Study: We prospectively evaluated our initial experience with
GreenLight XPS TM laser PVP. All patients who failed medical
therapy and/or surgery underwent GreenLight HPS TM laser PVP
(CW). All had American Urological Association Symptom Score
(AUASS), Sexual Health Inventory for Men (SHIM) score,
American Society of Anesthesiologists (ASA) risk score, serum
prostate specific antigen (PSA), maximum flow rate (Qmax) and
post void residual (PVR) determinations and volumetric
measurements with transrectal ultrasonography. Transurethral
PVP was performed using a GreenLight XPS TM side-firing laser
system.
Results: Eight consecutive patients were identified, having a
mean age of 73.0 12.1 years. The mean prostate volume was
67.5 16.4 ml and mean ASA score was 3.1 0.6. Mean laser
time, operating time and energy usage were 5.9 3.0 minutes,
24.0 11.0 minutes, and 79.8 17.9 kJ, respectively. All were
outpatient procedures with six (75.0%) patients catheter-free at
discharge. One (12.5%) patient required catheter drainage for 1
week. One (12.5%) patient developed a urinary tract infection.
None had persistent hematuria > 1 week or post-procedure
irritative voiding symptoms. No bladder neck contractures or
urethral strictures have been noted. Mean AUASS decreased from
24.6 at baseline to 7.3 and 6.9 at 1 and 4 weeks. Q max and PVR
values also showed statistical significant improvement (P < 0.05).
Conclusion: Our preliminary results suggest that GreenLight
XPS TM laser PVP is safe, effective and efficient for the
treatment of LUTS secondary to BPH. Continued follow-up is in
progress.
#189
INCIDENCE OF URETERAL STRICTURES
FOLLOWING LASER ABLATION OF TCC
Kelly Healy, Arturo Colon-Herdman,
Nicholas Leone, Scott Hubosky, Demetrius Bagley,
Thomas Jefferson
Philadelphia, PA
Background: The holmium and neodymium:YAG lasers are
commonly used for the endoscopic treatment of upper tract
transitional cell carcinoma (TCC). Laser ablation is an efficacious
nephron-sparing surgical option in select patients. However,
ureteral stricture is a recognized complication of ureteral tumor
laser ablation. The aim of this study was to evaluate the rate of
ureteral stricture formation following laser ablation of ureteral
tumors.
Study: We analyzed all consecutive patients undergoing ureteral
tumor laser ablation over a 3-year period at our institution by a
single surgeon. Operative histories were reviewed for prior upper
tract TCC treatment episodes. The amounts of Ho:YAG and
Nd:YAG laser energy used for ureteral tumor ablation were
recorded for each treatment episode. All subsequent operative
reports were reviewed for documentation of a new diagnosis of
ureteral stricture based on endoscopic and/or radiographic
findings after at least one ureteral tumor treatment.
Results: A total of 32 patients (36 treated ureters) had complete
data available for analysis. Of these, 44.4% (16/36) were
eventually diagnosed with a ureteral stricture on either follow-up
ureteroscopy or retrograde ureterography. Ho:YAG laser was
used in all treated ureters, whereas Nd:YAG laser was used in
only 27.8% (10/36) ureters. The strictured ureters had received a
mean cumulative dose of 2.35 3.16 kJ Ho:YAG compared to
2.53 4.50 kJ Ho:YAG among non-strictured ureters (P ¼ 0.88).
While strictured ureters received a mean cumulative dose of
1.91 4.80 kJ Nd:YAG, non-strictured ureters received a mean
cumulative dose of only 0.19 0.45 kJ Nd:YAG (P ¼ 0.11). No
significant difference in mean tumor size was detected between
the two groups (strictured 18.74 mm vs. non-strictured 13.33 mm,
P ¼ 0.20).
Conclusion: Among patients undergoing Nd:YAG laser ablation
of ureteral tumors, we demonstrated a trend toward increased