Photoselective vaporization of the prostate with the potassium-titanyl-phosphate laser in men with prostates of >100 mL.

OBJECTIVES: To assess the efficacy of photoselective vaporization of the prostate (PVP) in men with prostates of >100 mL and causing bladder outlet obstruction (BOO), using the high-power 80 W potassium-titanyl-phosphate laser (GreenLight PV, Laserscope, San Jose, CA, USA), which offers rapid tissue ablation with minimal bleeding. PATIENTS AND METHODS: We assessed 54 consecutive patients with prostates of >100 mL (mean 135, SD 42, range 100-300) who had PVP between May 2003 and August 2005. Evaluations before PVP included urine flowmetry, the International Prostate Symptom Score (IPSS), a quality-of life (QoL) score, prostate-specific antigen (PSA) level, and prostate volume measured by transrectal ultrasonography (TRUS). RESULTS: The mean (SD, range) duration of PVP was 81.6 (22.9, 39-150) min, the mean energy used for PVP was 278 (60, 176-443) kJ and the mean duration of catheterization after PVP was 23.0 (17.1, 0-72) h. The mean (sd) maximum urinary flow rate improved from 8.0 (3.1) to 18.2 (8.1), 18.5 (9.2), 17.9 (7.8) and 19.3 (9.8) mL/s at 3, 6, 12 and 24 months, respectively. The IPSS and QoL scores showed similar improvements, and there was a statistically significant reduction in PSA level and prostate volume after PVP. There was no major complication and no patient had transurethral resection syndrome or a blood transfusion. CONCLUSIONS: The 80 W KTP laser PVP offers rapid tissue ablation in patients with BOO caused by a large prostate. The short- and medium-term outcomes show that this technique can be a viable alternative to open prostatectomy.

Selenium- or quercetin-induced retardation of DNA synthesis in primary prostate cells occurs in the presence of a concomitant reduction in androgen-receptor activity.

Prostate cancer (CaP) is the most common male malignancy in the Western world. Selenium or quercetin may down-regulate prostate-cell proliferation in immortalised cells (e.g. androgen-responsive LNCaP cells). However, whether such effects are apparent in primary prostate epithelial cells (PECs) remains to be examined. Following surgical resection, primary PECs isolated from tissues (n=10 patients) were cultured in the presence or absence of selenium, selenomethionine or quercetin. Tissues from a minimum of three patients were used to generate cell preparations that were cultured independently for the purposes of the experimental analysis of each test agent. These agents were also examined in LNCaP cells. DNA synthesis was assessed by the percentage of PECs or LNCaP cells that incorporated 5-bromo-2-deoxyuridine (BrdU) into DNA. All three test agents induced a dose-related reduction in the percentage of PECs or LNCaP cells labelled with BrdU. In LNCaP cells transfected with an androgen-receptor (AR)-reporter gene coupled to luciferase, selenomethionine or quercetin reduced AR activity. Chemoprevention may retard DNA synthesis in short-term primary PECs and expression of AR-inducible elements may be a concomitant factor.

High-power KTP laser prostatectomy: the new challenge to transurethral resection of the prostate.

PURPOSE OF REVIEW: The quest for a successful surgical modality that can be used in the day-case setting, with minimal risk of complications and without the need for postoperative catheter drainage, may finally be fulfilled in the form of the new-generation, high-power potassium titanyl phosphate (KTP) lasers. In this review we will trace the development of KTP laser technology and its use by urologists over the years and describe why its physical properties make it so different from the lasers of the past. RECENT FINDINGS: The most high powered (80 W) incarnation has a relatively short history, particularly in terms of peer-reviewed publications. We will, however, outline the data so far and demonstrate what an exciting tool this represents for the urologist not only in terms of qualitative and quantitative improvements in lower urinary tract symptoms, but also in offering a day case, and in some instances catheterless, procedure with the prospect of a significantly lower impact on sexual function compared with standard surgical options. SUMMARY: Despite the lack of long-term data it is certainly possible that high-power KTP lasers represent a very significant challenge to the 'gold standard' status of transurethral resection of the prostate. Furthermore, the ability to use this technology to safely and effectively treat very large prostates represents an opportunity to assign the associated morbidity of the open prostatectomy to the annals of history.