Dirk P.J. Michielsen

Initial clinical experience with infrared-reflecting skin markers in the positioning of patients treated by conformal radiotherapy for prostate cancer

PURPOSE To evaluate an infrared (IR) marker-based positioning system in patients receiving conformal radiotherapy for prostate cancer. METHODS AND MATERIALS During 553 treatments, the ability of the IR system to automatically position the isocenter was recorded. Setup errors were measured by means of orthogonal verification films and compared to conventional positioning (using skin drawings and lasers) in 184 treatments. RESULTS The standard deviation of anteroposterior (AP) and lateral setup errors was significantly reduced with IR marker positioning compared to conventional: 2 vs. 4.8 mm AP (p < 0.01) and 1.6 vs. 3.5 mm laterally (p < 0.01). Longitudinally, the difference was not significant (3.5 vs. 3.0 mm). Systematic errors were on the average smaller AP and laterally for the IR method: 4.1 vs. 7.8 mm AP (p = 0.01) and 3.1 vs. 5.6 mm lateral (p = 0.07). Longitudinally, the IR system resulted in somewhat larger systematic errors: 5.0 vs. 3.4 mm for conventional positioning (p = 0.03). The use of an off-line correction protocol, based on the average deviation measured over the first four fractions, allowed virtual elimination of systematic errors. Inability of the IR system to correctly locate the markers, leading to an executional failure, occurred in 21% of 553 fractions. CONCLUSION IR marker-assisted patient positioning significantly improves setup accuracy along the AP and lateral axes. Executional failures need to be reduced.

INFLUENCE OF SACRAL NEUROMODULATION ON ELECTROSENSATION OF THE LOWER URINARY TRACT

PURPOSE We prospectively investigated whether neuromodulation of the S3 root influences the sensory threshold to electrical stimulation in the lower urinary tract. MATERIALS AND METHODS The study included 7 women and 3 men receiving S3 neuromodulation at 210 msec. and 25 Hz. with the Interstim PNE system for a mean of 5 days. Neuromodulation was done unilaterally in 6 cases and bilaterally in 4. The sensory threshold was determined by electrodes placed randomly against the mucosa of the empty bladder on the left and right sides, in the urethra in women, and in the prostatic and penile urethra in men. Thresholds were measured at each location with neuromodulation on and off. RESULTS With bilateral neuromodulation on all 4 patients had a lower bladder threshold than with neuromodulation off. In unilateral neuromodulation the threshold was significantly lower during neurostimulation on the ipsilateral side. There was no effect on the threshold on the arm or in the urethra. The effect was noted in patients in whom neuromodulation was and was not clinically successful. CONCLUSIONS Neuromodulation on S3 influences the nervous system involved in electrosensation of the bladder but not the skin afferent innervation or the nerves involved in urethral electrosensation. These data support the hypothesis that S3 neurostimulation is effective mainly through the afferent nervous system in the pelvic nerves.

Clinical use of stereoscopic X-ray positioning of patients treated with conformal radiotherapy for prostate cancer.

PURPOSE To evaluate accuracy and time requirements of a stereoscopic X-ray-based positioning system in patients receiving conformal radiotherapy to the prostate. METHODS AND MATERIALS Setup errors of the isocenter with regard to the bony pelvis were measured by means of orthogonal verification films and compared to conventional positioning (using skin drawings and lasers) and infrared marker (IR) based positioning in each of 261 treatments. In each direction, the random error represents the standard deviation and the systematic error the absolute value of the mean position. Time measurements were done in 75 treatments. RESULTS Random errors with the X-ray positioning system in the anteroposterior (AP), lateral, and longitudinal direction were (average +/- 1 standard deviation) 2 +/- 0.6 mm, 1.7 +/- 0.6 mm, and 2.4 +/- 0.7 mm. The corresponding values of conventional as well as IR positioning were significantly higher (p < 0.01). Systematic errors for X-ray positioning were 1.1 +/- 1.2 mm AP, 0.6 +/- 0.5 mm laterally, and 1.5 +/- 1.6 mm longitudinally. Conventional and IR marker-based positioning showed significantly larger systematic errors AP and laterally, but longitudinally, the difference was not significant. Depending on the axis looked at, errors of >or=5 mm occurred in 2%-14% of treatments after X-ray positioning, 13%-29% using IR markers, and 28%-53% with conventional positioning. Total linac time for one treatment session was 14 min 51 s +/- 4 min 18 s, half of which was used for the X-ray-assisted positioning procedure. CONCLUSION X-ray-assisted patient positioning significantly improves setup accuracy, at the cost of an increased treatment time.

Urethral Strictures and Bipolar Transurethral Resection in Saline of the Prostate: Fact or Fiction?

PURPOSE To compare the incidence of urethral strictures after monopolar transurethral resection of the prostate (TURP) and bipolar transurethral resection in saline (TURIS) for symptomatic benign prostatic hyperplasia. PATIENTS AND METHODS Between January 2005 and January 2009, 518 patients with symptomatic benign prostate hyperplasia underwent either monopolar or bipolar resection. In a randomized trial, the incidence of urethral strictures after both treatment modalities was analyzed. RESULTS Over 48 months, 255 patients were treated with conventional TURP and 263 patients with TURIS. Patient related, operation, and hospitalization characteristics were similar in both groups. After a mean follow-up of 32.1 months (range 50-7 months), the incidence of urethral strictures was 2.4% in the TURP group. After a comparable period of 31.4 months (range 50-7 months), the incidence in the TURIS group was 1.5%. No statistically significant difference was obtained (P = 0.539). These values were compared with the results of other randomized controlled trials with the same or other bipolar technology. No statistically significant difference in urethral structures was noticed between monopolar and bipolar resections (P = 0.739). CONCLUSIONS With a stricture incidence of 1.5%, bipolar transurethral prostate resection has a low stricture rate, comparable with monopolar TURP (2.4%).

Bipolar transurethral resection in saline: The solution to avoid hyponatraemia and transurethral resection syndrome

Abstract Objective. To compare serum sodium changes and the incidence of transurethral resection (TUR) syndrome after monopolar transurethral resection of the prostate (TURP) and bipolar transurethral resection in saline (TURIS) for symptomatic benign prostatic hyperplasia. Material and methods. Between January 2005 and August 2009, 550 consecutive patients with symptomatic benign prostate hyperplasia underwent TURP, by either a monopolar or bipolar technique. Preoperative and postoperative blood parameters were analysed to compare preoperative and postoperative electrolyte concentrations. Results. Over 56 months, 265 patients underwent a conventional monopolar TURP and 285 patients had a bipolar TURIS (Olympus). Patient profiles regarding age, operation time, resection weight and resection speed were similar in both groups. A drop in sodium of 2.5 mmol/l was measured in the conventional monopolar resection group. The decline of 1.5 mmol/l in the bipolar group, although smaller, was still statistically significant (p = 0.001). With longer operation times (> 1 h) the difference between the groups became more important (p < 0.001). Two clinical TUR syndromes were observed in the monopolar group, while none occurred in the bipolar group. Conclusions. Bipolar TURP in saline is a safe technique and obviates the risk of TUR syndrome. Repeated serum analysis of electrolytes after TURIS can be omitted.

Conventional monopolar resection or bipolar resection in saline for the management of large (>60 g) benign prostatic hyperplasia: An evaluation of morbidity

Abstract The objective of this study was to compare the efficacy and safety of bipolar transurethral resection in saline (TURIS) and conventional monopolar transurethral resection (TURP) in men with voiding difficulties due to high volume (>60g) benign prostatic hyperplasia. Between May 2005 and January 2009, 66 men with bladder outlet obstruction due to large benign hyperplasia (BPH) (>60 g) underwent transurethral resection, either by Olympus monopolar or Olympus bipolar TURIS technique. Perioperative and outcome data were recorded and compared. There was no significant difference in patient age, prostate size, PSA, uroflow rate, post voiding residual urine, operation time, catheterization time, and hospital stay. In the monopolar TURP group, an important drop in serum sodium was observed (3.12 mmol/L), statistically significantly different (p = 0.012) from the 1.30 mmol/L drop in the bipolar TURIS group. One case of clinical TUR syndrome was observed in the conventional monopolar TURP group. Early and late complications such as clot retention, urinary retention, bladder neck stenosis, and urethral stricture were identical in both groups. The bipolar TURIS device is a valid treatment option for patients with BPH-related voiding disorders due to high volume BPH. Obviating the risk of TUR syndrome, this minimally invasive procedure may be a good surgical option in the urologists armamentarium.

Comparison of the haemostatic properties of conventional monopolar and bipolar transurethral resection of the prostate in patients on oral anticoagulants.

Introduction The aim of study is comparing the haemostatic properties of conventional monopolar resection (TURP) and bipolar transurethral resection in saline (TURIS) of the prostate in patients under chronic oral anticoagulants. Material and methods Out of a cohort group of 550 endoscopic resections for bladder outlet obstruction, 176 patients on chronic oral anticoagulant therapy required endoscopic resection either by monopolar TURP or bipolar TURIS technology. Changes in haemoglobin, blood transfusion, and clot retention were compared between both groups. Results Mean postoperative change in haemoglobin level was –1.21 ±0.92 mg/dl in the TURP group compared to –1.29 ±0.99 mg/dl in the TURIS group (p = 0.603). The need for blood transfusions and the mean numbers of units transfused did not significantly differ between the 2 groups. Clot retention appeared in 12 patients (15%) in the TURP group compared to 13 patients (13%) in the TURIS group (p = 0.828). Conclusions Despite promising experimental results of better haemostasis and deeper coagulation depth, bipolar technology does not permit one to reduce the amount of blood loss when compared to patients treated by conventional monopolar technology in this study group of patients on oral anticoagulation therapy. Patients on oral anticoagulants suffer more incidents of clot retention, which sometimes results in re-hospitalisation.

Efficacy and tolerability of 1- and 3-month leuprorelin acetate depot formulations (Eligard®/Depo-Eligard®) for advanced prostate cancer in daily practice: a Belgian prospective non-interventional study

Introduction The 1-, 3- and 6- month biodegradable polymer matrix depot formulations of leuprorelin acetate (Eligard®/Depo-Eligard®, Astellas Pharma Inc/BV) were shown to reduce testosterone and prostate-specific antigen levels and to be well tolerated in patients with advanced prostate cancer in several clinical trials. This study aimed at evaluating the efficacy, safety and tolerability of the 1- and 3-month leuprorelin acetate depot formulations in daily clinical practice. Material and methods A prospective, open-label, non-interventional, phase IV study (MANTA) was conducted in 243 Belgian prostate cancer patients who had been prescribed the 1-month (7.5 mg) or 3-month (22.5 mg) leuprorelin acetate depot formulation. Patients were followed for at least 3 months. Results Median serum prostate-specific antigen levels were reduced by 95% from 12.0 ng/ml at baseline to 0.60 ng/ml after a median follow-up time of 132 days, while median testosterone levels were reduced by 94% from 360 ng/dl to 20 ng/dl. Partial or complete treatment response was observed in 83% of patients at the final visit (according to the physicians assessment). Ninety-two patients (37.86%) experienced treatment-emergent adverse events, with injection site-related reactions, hot flushes and tumor flare being the most common ones. Overall safety and tolerability of the leuprorelin acetate depot formulation were rated as good or excellent by 90% of physicians. Conclusions These data are consistent with efficacy and tolerability results from clinical trials. They confirm that the 1- and 3-month leuprorelin acetate depot formulations are well tolerated and reliably lower serum prostate-specific antigen and testosterone levels in routine clinical practice.

Bipolar versus monopolar technique for palliative transurethral prostate resection

Introduction The aim was to evaluate the postoperative morbidity and outcome of palliative endoscopic resections for relief of infravesical obstruction in prostate cancer patients with hormone deprivation therapy, and to investigate the added value of bipolar technology over conventional monopolar resections. Material and methods A retrospective study was performed on 70 patients with prostate cancer under hormone deprivation therapy undergoing 75 endoscopic procedures, by either monopolar or bipolar technology, between August 2005 and March 2009 at a single institution. The analysis used outpatient, inpatient, and operative records, and observations of electrolyte changes in the serum, postoperative morbidity, and the overall results of palliative endoscopic resections. Preoperative cancer stages and grades were compared with the pathological findings after surgery. Postoperative outcome and complications of conventional monopolar and bipolar technology were compared. Results Over a period of 44 months, 34 conventional monopolar resections were performed in 32 patients and 41 bipolar resections in 38 patients. Patients’ profiles regarding age, initial cancer stage and grade, resection weight, resection speed, catheterization time, and hospital stay were similar in both groups. No statistically significant difference was observed in sodium drop (p = 0.802), clot retention (p = 0.565), or urinary retention (p = 0.292). The overall success rate in relieving obstruction leading to spontaneous voiding was 77%. While 38% of the patients had a high grade tumour at diagnosis, 79% were found to be high grade after the endoscopic resection (p < 0.0001). Conclusions Palliative endoscopic transurethral resection is an acceptable and safe adjunctive surgical treatment for voiding disorders in prostate cancer patients. Bipolar technology offers no substantial benefit over conventional monopolar technology.

Prostate HistoScanning: A screening tool for prostate cancer?

To evaluate Prostate HistoScanning as a screening tool for prostate cancer in a pilot study.