Applications of lasers (light amplification by stimulated emission of radiation) in various disciplines of medicine including Urology are well developed. Urology is among the medical specialties that apply many different types of laser systems to treat a broad spectrum of clinical conditions ranging from genital, bladder and urethral tumors to the treatment of benign prostate hyperplasia (BPH), urethral strictures, and stones.
The specific application of various laser systems depends on the characteristics of the laser itself, delivery media for the beams, laser-tissue interaction and the desired effect. These complex conditions require an intensive and continuous exchange of information between non-medical researchers and physicians to verify "what is currently technically possible and what is medically needed". Only this exchange can lead to the development of new laser systems.
While lasers have become the treatment of choice in some conditions, they could not, despite excellent clinical results, replace conventional therapy options in others. Nonetheless, the use and the introduction of lasers of different wavelengths forces urologists to keep step with the fast developing laser technology.
This paper reviews current indications for clinical laser applications relevant to urology and the advantages and disadvantages of using lasers for the management of various urological lesions.
Laparoscopic radical prostatectomy (LRP) is a relatively new technique for treating organ-confined prostate cancer. Recent progress of laparoscopic/endoscopic techniques allow to perform these complex oncological procedure.
Since the first description of LRP in the early 1990s the technique has undergone significant technical modifications. Two operation routes were mainly used: the transperitoneal LRP and the extraperitoneal endoscopic radical prostatectomy (EERPE). Here we review the surgical techniques of both operation routes, and highlight results, outcome and complications.
The transperitoneal LRP and the EERPE can be used successfully and reproducibly, giving results comparable with those from the open retropubic procedure. Despite many advantages, transperitoneal LRP is associated with potential intraperitoneal complications. The technical improvements of the EERPE completely obviates these complications.
The available data are encouraging and promising, but long-term oncological results will define the definitive role of these new techniques. We truly believe that minimally invasive surgery in treating localized prostate cancer has a bright future and that these techniques will continue to be developed.
Photodynamic Therapy (PDT) is a treatment modality that is based on the administration of a photosensitizer and the following application of light in a wavelength range matching the absorption spectrum of the photosensitizer. Ideally the photosensitizer retains in the tumor tissue more than in normal tissue and thus allows targeted destruction of cancerous tissue. The use of PDT is slowly being accepted as a standard treatment for certain types of cancer. This includes mainly treatment strategies with only palliative intentions (obstructive esophageal cancer and advanced lung cancer) while for certain malignant conditions new applications exists that are already intended for cure (e.g. early stage of lung cancer). The main advantage of PDT is that the treatment can be repeated multiple times safely without major side effects. PDT can be safely combined with already established treatment options like surgery, chemotherapy or radiotherapy. A disadvantage of PDT is the only localized effect of the therapy, which usually cannot significantly alter the outcome of a systemic disease. In this paper we review the history of PDT as well as current clinical applications in oncology and future directions.
Renal tumors are increasingly detected on abdominal imaging studies. Standard treatment of small renal tumors includes partial or radical nephrectomy, done either open or laparoscopically. Several in situ ablative techniques to treat small renal lesions are currently in various phases of evolution. All involve imparting destructive energy to the tumor while minimizing injury to adjacent normal tissue. Cryotherapy (CryoT), radiofrequency ablation (RFA), high-intensity focused ultrasound (HIFUS) and high-intensity radiation (HIR) are all being evaluated as tools to ablate renal tumors. The goal with these modalities is to minimize the blood loss, tissue manipulation, and morbidity associated with excisional approaches. Animal studies have shown that large, reproducible lesions can be ablated in normal kidney tissue by these new techniques. Studies of human renal tissue response to RFA are just beginning. Ex vivo studies reveal large, reproducible controlled lesions in normal renal tissue, similar to animal studies. In vivo studies have shown no significant toxicity, while efficacy is currently under evaluation. Preliminary clinical studies in humans have revealed that renal tumors are slow to regress after treatment, but about 75% of these small renal tumors appeared well treated. Mixed responses have been observed in the remaining cases. This paper presents a concise review of efficacy, advantages and disadvantages of these new minimal invasive techniques and their possible clinical implication in the future.
Urinary tract symptoms related to benign prostatic hyperplasia affect 70% of men older than 70 years. Complications are common problems and a significant cause of morbidity in this population, placing a considerable burden on health services. In the early 1990s laser treatment of benign prostatic hyperplasia became widely used after the introduction of the side-firing neodym: YAG laser. However, because of technical limitations and inferior results compared to classical transurethral resection of the prostate many Urologists became desinterested in this device. With the introduction of the holmium: YAG laser a new laser generation became available for use in Urology. Beside several other applications the holmium: YAG laser can be used for incision, ablation, resection, and more recently enucleation of the prostate. In this paper we reviewed the current literature regarding the holmium: YAG laser resection and enucleation of the prostate compared to transurethral resection of the prostate and open prostatectomy. The holmium: YAG laser technique is an effective and durable surgical alternative to standard transurethral resection of the prostate. Interestingly, enucleation of the prostate with this device seems to be a safe and effective procedure for large prostatic adenomas, it may become an attractive alternative to open prostatectomy.
Completeness and certainty of tumor detection are very important issues in clinical oncology. Recent technological developments in ultrasound, radiologic and magnetic resonance imaging diagnostics are very promising, but could not improve the detection rate of early stage malignancies. One of the most promising new approaches is the use of 5-aminolevulinic acid, a potent photosensitizer, in photodynamic diagnosis and therapy. 5-aminolevulinic acid is meanwhile a well-established tool in the photodynamic diagnosis of bladder cancer. It has been shown to improve the sensitivity of detection of superficial tumors and carcinoma in situ, which enables to reduce the risk of tumor recurrence related to undetected lesions or incomplete transurethral resection of the primary lesions. The use of 5-aminolevulinic acid is steadily expanding in diagnostics of urological malignancies. First clinical results are now reported in detection of urethral and ureteral lesions as well as in urine fluorescence cytology. Furthermore, due to the selective accumulation in transitional cell carcinoma of the bladder, 5-aminolevulinic acid may be an ideal candidate for photodynamic therapy in superficial bladder cancer. Summarizing the data of multiple clinical trials, 5-aminolevulinic acid is a promising agent in photodynamic diagnostics and treatment of superficial bladder cancer.
Objectives: The treatment of female urinary incontinence (UI) is a growing health care concern in our aging society. Publications of recent innovations and modifications are creating expectations. This brief review provides some insight and structure regarding indications and expected outcomes for the different approaches.
Materials: Data extraction is part of a Medline data base search, which was performed for "female stress incontinence" from 1960 until 2000. Additional literature search was performed to cover 2001 and 2002. Outcome data were extracted.
Results: (1) INJECTION OF BULKING AGENTS (collagen, synthetic agents): The indication for mucosal coaptation was more clearly defined and in the majority of articles limited to ISD.
(2) OPEN COLPOSUSPENSION (Burch, MMK): Best long-term results of all operative procedures, to date considered the gold standard.
(3) LAPAROSCOPIC COLPOSUSPENSION (different modifications): Long-term success rates appear dependent on operator skills. There are few long-term data.
(4) NEEDLE SUSPENSION: (Stamey, Pareyra and modifications):
Initial results were equal to Burch with less morbidity, but long-term success rates are worse.
(5) SLING PROCEDURES (autologous, synthetic, allogenic graft materials, different modes of support and anchoring, free tapes):
The suburethral sling has traditionally been considered a procedure for those in whom suspension had failed and for those with severe ISD. The most current trend shows its use as a primary procedure for SUI. Long-term data beyond 5 years are insufficient.
(6) EXTERNAL OCCLUSIVE DEVICES (vaginal sponges and pessaries, urethral insert): Both vaginal and urethral insert devices can be effective in selected patients.
(7) IMPLANTABLE ARTEFICIAL URETHRAL SPHINCTERS: Modifications and improvements of the devices resulted in improved clinical results regarding durability and efficacy.
CONCLUSION: (1) The Burch colposuspension is still considered the gold standard in the treatment of female genuine SUI. There is a trend for the suburethral sling to be used as the primary procedure for this indication. Early outcome data are encouraging. New concepts such as use of metalic bone anchors and allograft material as well as the Tension free Vaginal Tape are under investigation.
(2) Standardization of diagnostic and therapeutic interventions is prerequisite for any meaningful research. Randomized controlled prospective studies are essential to provide objectives regarding risks and benefits of new procedures and materials.
The use of minimally invasive treatments for benign prostatic hyperplasia (BPH) have been introduced into the medical community. Over the last decade several minimally invasive treatment techniques have been approved for use. In particular, interstitial laser coagulation (ILC) has shown pomise as an alternative to the current gold standard, transurethral resection of prostate (TURP). Studies show ILC to have equal efficacy as TURP while causing less side effects. Future technical advances as well as increased physician experience with ILC could lead to the replacement of TURP as the gold standard in trestment of BPH.
Benign prostatic hyperplasia (BPH) is a common disease in males older than 50 years of age. 75-80% of this population is considered to have some degree of BPH causing clinical symptoms and requiring urological treatment. Transurethral resection of the prostate (TUR-P) is currently the standard surgical treatment modality for BPH. In an attempt to minimize the need for hospitalization and the associated perioperative and postoperative morbidity, alternatives have been sought. Various types of Laser techniques such as interstitial Laser cogaulation and side-firing technology have been proposed. Numerous studies have shown that Laser procedures safely and effectively reduce the volume of the prostate. Intra- and postoperative bleeding are nearly unknown complications for Laser procedures, whereas this is the most relevant complication for the TUR-P. Due to significant tissue edema after Laser treatment, patients commonly show delayed time to void adequately, and therefore, catheter drainage is often necessary for 3 to 21 days. Retrograde ejaculation is reported to occur less (0 - 10%) compared to TUR-P (> 60%). Urinary tract infections are very common after interstitial laser coagulation. Although not many long-term clinical data are available, various studies have shown that BPH patients improve in symptom score, flow rate and post-void residual up to 3 years after Laser treatment. This paper presents a concise review of efficacy, advantages and disadvantages of the most frequently used Laser techniques as well as the long-term clinical data compared to TUR-P.
In the United States about 50,000 men with organ-confined prostate cancer undergo radiation therapy each year. Depending on the source of the data and the definition of treatment failure, estimates of cancer recurrence after radiation therapy vary widely from 10% up to 50%. Patients who fail radiation have a choice of hormonal treatment, which unfortunately is only palliative, and salvage radical prostatectomy, a procedure that can be very difficult with significant comorbidities. If the patient decides for watchful waiting, tumor progression and metastatic disease are only a matter of time. Due to these clinical problems there is a need for new techniques to provide local salvage therapy. New developments in cryotherapy and endoscopic laser application such as thermocouples and ultrasound monitoring have led to decline in morbidity such as urinary incontinence. This paper presents a concise review of clinical data of salvage therapy in patients with local tumor recurrence after radiation. Only limited studies are available for laser treatment due to problems in tissue penetration and intraoperative monitoring. There is more data available dealing with cryotherapy, where argon-based cryosurgery is most common. Patients with a Gleason score < 8 and a PSA serum level less than 8.0 ng/ml seem to benefit compared to those who did not meet these criteria. Cumulative retrospective data show that with a mean follow-up of 24 months, 60% of the treated patients have a serum PSA nadir of < 0.1 ng/ml and 30% < 4.0. However, the data reviewed are primarily retrospective case series, which are particularly prone to bias. Prospective clinical studies including quality of life data are necessary in order to clarify the clinical relevance of these new techniques in salvage surgery.
Transitional cell carcinoma (TCC) of the bladder has a 40-70% local recurrence rate when treated with transurethral resection (TURBT)1 and carcinoma in situ (CIS) has a 54-83% recurrence rate within 4 years2. Today, the main therapy is intravesical chemotherapy, of which Bacillus Calmette-Guerin (BCG) is the most effective. However, because chemotherapy is only modestly beneficial3 and most bladder carcinomas will not respond to second course of BCG4, an additional treatment modality is being researched. Photodynamic therapy (PDT) combines a photosensitizing dye with laser therapy to destroy cancer cells. Pathologic cells take up the photosensitizing agent and upon activation by visible light (400 - 760 nm) the cancerous cells are destroyed. PDT can be used for focal or diffuse disease. It also can be used to treat recurrent and refractory superficial TCC, in addition to being used as a prophylactic measure. We review the literature (mostly retrospective or nonrandomized studies) that supports the use of PDT for TCC of the bladder. While PDT seems to be a very promising treatment modality, BGC intravesical treatment remains the standard of care for TCC. However if additional randomized trials confirm current data, PDT may soon be a recommendable option.
Transitional cell carcinoma (TCC) of the bladder is most common genitourinary tract cancer and its treatment comprises a large number of surgical procedures in urological oncology. Seventy-five percent (75%) of cases recur within two years and the recurrence rate is correlated with the grade of the initial tumor. While Transurethral Resection of the Bladder (TURB) is the current standard of care, the use of laser offers a proven alternative. Sufficient evidence is available that laser treatment of superficial bladder cancer is as effective as TURB. Laser treatment offers several advantages such as decreased incidence of bladder perforation, a near bloodless procedure, catheter-free procedure, and the possibility of outpatient therapy. It has been reported that laser treatment may reduce the recurrence rate of TCC as compared to electrocautery resection. Furthermore, some studies suggest seeding can be avoided with laser resection; however, both items remain highly controversial.
Benign prostatic hyperplasia (BPH) is a common disease in males older than 50 years of age. 75-80% of this population is considered to have some degree of BPH causing clinical symptoms and requiring urological treatment. Transurethral resection of the prostate (TUR-P) is currently the standard surgical treatment modality for BPH. In an attempt to minimize the need for hospitalization and the associated perioperative and postoperative morbidity, alternatives have been sought. Various types of laser techniques such as interstitial laser coagulation and side-firing technology have been proposed. Numerous studies have shown that laser procedures safely and effectively reduce the volume of the prostate. Intra- and postoperative bleeding are nearly unknown complications for laser procedures, whereas this is the most relevant complication for the TUR-P. Due to significant tissue edema after laser treatment, patients commonly show delayed time to void adequately and, therefore, catheter drainage is often necessary for 3 to 21 days. Retrograde ejaculation is reported to occur less (0- 10%) compared to TUR-P (greater than 60%). Urinary tract infections are very common after interstitial laser coagulation. Although not many long-term clinical data are available, various studies have shown that BPH patients improve in symptom score, flow rate and post-void residual up to 3 years after laser treatment. This paper presents a concise review of efficacy, advantages and disadvantages of the most frequently used laser techniques as well as the long-term clinical data compared to TUR-P.
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