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Query: UMLS:C0005684 (bladder cancer)
 16,431 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The clinical application of photodynamic therapy (PDT) began in the late 1970's. Hematoporphyrin derivative has been used as a photosensitizer and recently Photofrin II (Dihematoporphyrin ether, DHE) was also developed as a second generation photosensitizer. The argon dye laseris used to excite the photosensitizer, however an eximer dye laser was recently developed as more effective laser. In a multicenter research study project team (7 institutions) on photodynamic therapy organized by the Ministry of Health and Welfare, 133 cases of gastric cancer (including 120 cases of early stage cancer), 209 cases of lung cancer (69 cases of early stage cancer), 66 cases of esophageal cancer (22 cases of early stage cancer), 68 cases of bladder cancer (68 cases of early stage cancer), and 86 cases of other organ cancers were treated. In early stage cancer cases 77.3% showed complete remission (CR) but among those the recurrence was 15.7% in lung cancer cases and opposed to 100% CR and 22.2% recurrence in gastric cancer cases, 80% CR and no recurrence in esophageal cancer cases, and 68.6% CR and 58.3% recurrence in bladder cancer cases. Especially in limited lesions less than 1 cm in diameter, the CR was obtained in 100% and the recurrence was recognized in only 1 (2.6%) of 28 lung cancer lesions, 100% CR and no recurrence was obtained in 30 lesions of gastric cancer and also 100% CR with no recurrence was recognized in 16 lesions in bladder cancer. This study suggests that PDT has the potential to cure early stage cancer lesions.
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PMID:[Photodynamic therapy in the early treatment of cancer]. 220 15

Photodynamic therapy for bladder cancer is an intriguing modality with theoretical potential for successful treatment of visible tumor and areas of carcinoma in situ and dysplasia throughout the bladder mucosa. There remain many unanswered determinations about photodynamic therapy, including the most effective photosensitizer, the dose of laser that should be used, and the optimum timing for laser therapy following the injection of photosensitizer. Nonetheless, clinical studies thus far have shown photodynamic therapy to have efficacy in eradicating superficial noninvasive tumors. Treatment of diffuse carcinoma in situ at present appears the most impressive. Prospective studies designed to examine photodynamic therapy in a standardized protocol in comparison with other conventional methods for treatment and prophylaxis of noninvasive bladder cancer are most needed and are currently in progress. In the future, development of alternate photosensitizers or methods of direct intravesical uptake of DHE, perhaps limiting cutaneous phototoxicity, are expected.
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PMID:Photodynamic therapy of bladder carcinoma. 294 10

If transurethral resection and intravesical treatment with BCG or chemotherapeutic agents are unsuccessful in recurrent flat multifocal superficial bladder cancer, cystectomy is considered to be indicated. A whole-bladder photodynamic therapy (PDT) was carried out in 23 patients in this worst-case situation, in 19 of whom minimum follow-up of 3 months has been possible. In 5 patients with carcinoma in situ and in 14 patients with flat papillary tumors covering nearly the whole bladder, Photofrin or Photosan-3 was applied intravesically. Irradiation of the bladder followed about 48 h, later with a light dose of 15 J/cm2 or 30 J/cm2 at a wave length of 630 nm. In 12 patients complete remission was achieved; 7 patients showed no evidence of disease over a follow-up period of 3-31 months (median 16.3 months). One patient was lost to follow-up. In 7 patients recurrent disease or residual tumor was observed following PDT, but these were easily managed by transurethral resection or Nd:YAG laser coagulation. In 4 patients PDT failed and cystectomy was carried out. Systemic progression was not observed. PDT has to be regarded as an alternative to cystectomy in the treatment of refractory superficial bladder cancer.
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PMID:[Photodynamic therapy of superficial bladder cancer. An alternative to radical cystectomy?]. 794 Nov 72

Photodynamic therapy utilizing Photofrin has proven to be an effective modality that can be used in the treatment of a wide variety of solid tumors and luminal cancers. An argon pumped dye laser or excimer dye laser was used to deliver 630 nm light via quartz fibers passed through the biopsy channel subsequent to i.v. injection of photosensitizer. In this study, 64 patients with superficial cancers were treated in this manner but only 58 patients, including 21 with roentgenographically occult lung cancer, 8 with stage I lung cancer, 5 with esophageal cancer, 12 with gastric cancer, 8 with cervical cancer and 4 with bladder cancer were evaluable. Complete remission was obtained in 48 out of 58 cases (82.8%). There was no serious complication except skin photosensitivity, which was seen in 13 patients. We conclude that photodynamic therapy is efficacious in the treatment of superficial cancers where complete remission may be achieved.
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PMID:Photodynamic therapy for cancers: a clinical trial of porfimer sodium in Japan. 827 25

Photodynamic therapy (PDT) using Photofrin IIR (PII) as a photosensitizer is currently being evaluated as a new treatment modality for superficial bladder cancer. An optimum therapeutic ratio requires uniform illumination of the whole bladder wall and accurate light dosimetry. The first clinical light dosimetry results (16 patients) are reported, obtained using a system which allows in situ measurement and control of the light fluence at the bladder wall. The true light fluence at the bladder wall (i.e. non-scattered incident light plus scattered light) appeared to be on the average a factor beta = 4.8 +/- 1.2 (mean +/- SD) larger than the non-scattered incident light fluence. The latter is often, but incorrectly, used in reporting light fluence. The factor beta varied between patients with extremes of 2.5 and 7.1. Because such large variations were unexpected, but may have significant clinical consequences, experiments in plastic bladder models were performed to study separately the various factors (e.g. bladder shape, air bubble) affecting the dosimetry in clinical treatments. The results imply that the clinical variations are most likely to be the result of variations in optical properties of the bladder wall mucosa, probably due to the disease and prior treatments. If light dosage is based on non-scattered light only (without in situ light dosimetry, according to a current clinical protocol) the present results indicate variations in the true (total) light fluence between patients by a factor of at least 2. At the least this may cause unnecessary discomfort to a number of patients.
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PMID:In situ light dosimetry during whole bladder wall photodynamic therapy: clinical results and experimental verification. 832 87

PDT and IUdR-sensitized radiation therapy represent potential advances in the treatment of tumors of the head and neck. Light-activated photosensitizers have definite antitumor activity in both in vitro and in vivo experimental systems. Much of the early clinical work in head and neck cancer involved treatment of patients with advanced, recurrent disease who had not responded to conventional therapy. Because of the limited light penetration in tissue and infiltrative nature of most recurrent lesions, little effective palliation was seen in these advanced cases. More success has been achieved in the treatment of earlier, more superficial lesions, and active investigation continues in this area. Current research is aimed at defining the most appropriate sites and applications for the technique. HpD and DHE are currently only approved for use as investigational compounds in clinical studies. If ongoing trials of PDT in the treatment of superficial bladder cancer, obstructing esophageal cancer, and non-small cell lung cancer show encouraging results, an application will be made to the Food and Drug Administration for approval of DHE as a photosensitizer for general clinical use for these indications. Laboratory work to better understand the mechanism of action of HpD also continues, as well as investigations into alternative photosensitizers with improved tumor localization, less cutaneous photosensitivity, and absorption peaks at deeper penetrating wavelengths of light. A pilot program evaluating IUdR-sensitized radiation therapy for treatment of advanced head and neck cancer is in progress. If encouraging early results continue to be observed, a randomized trial comparing IUdR-sensitized radiation therapy with conventional radiation therapy can be conducted. Hopefully, these developments in the field will improve the therapy for patients with head and neck cancers.
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PMID:Sensitizers of photoradiation and ionizing radiation in the management of head and neck cancer. 849 11

The first reports on photodynamic therapy (PDT) date back to the 1970s. Since then, several thousands of patients, both with early stage and advanced stage solid tumours, have been treated with PDT and many claims have been made regarding its efficacy. Nevertheless, the therapy has not yet found general acceptance by oncologists. Therefore it seems legitimate to ask whether PDT can still be described as "a promising new therapy in the treatment of cancer". Clinically, PDT has been mainly used for bladder cancer, lung cancer and in malignant diseases of the skin and upper aerodigestive tract. The sensitizer used in the photodynamic treatment of most patients is Photofrin, (Photofrin, the commercial name of dihematoporphyrin ether/ester, containing > 80% of the active porphyrin dimers/oligomers (A.M.R. Fisher, A.L. Murphee and C.J. Gomer, Clinical and preclinical photodynamictherapy, Review Series Article, Lasers Surg. Med., 17 (1995) 2-31). It is a complex mixture of porphyrins derived from hematoporphyrin. Although this sensitizer is effective, it is not the most suitable photosensitizer for PDT. Prolonged skin photosensitivity and the relatively low absorbance at 630 nm, a wavelength where tissue penetration of light is not optimal, have been frequently cited as negative aspects hindering general acceptance. A multitude of new sensitizers is currently under evaluation. Most of these "second generation photosensitizers" are chemically pure, absorb light at around 650 nm or greater and induce no or less general skin photosensitivity. Another novel approach is the photosensitization of neoplasms by the induction of endogenous photosensitizers through the application of 5-aminolevulinic acid (ALA). This article addresses the use of PDT in the disciplines mentioned above and attempts to indicate developments of PDT which could be necessary for this therapy to gain a wider acceptance in the various fields.
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PMID:Photodynamic therapy: a promising new modality for the treatment of cancer. 876 58

Photodynamic therapy (PDT) has gained popularity in the past 10 years because of advances in laser and pharmacokinetic technologies and the development of new photosensitizers. Early studies on PDT with focal illumination for papillary bladder cancer obtained reasonable response rates for small tumors but recurrence was common. Whole bladder irradiation, once a suitable light-delivery system had been developed, gave promising outcomes with acceptable rates of complications. PDT for prostate cancer is still at the experimental stage but initial results have been promising. Clinical trials of PDT for brain tumors have shown no significant complications but no improvement in survival rate compared with other treatment modalities. PDT is particularly useful for early superficial lung cancers that are localized to one or a few discrete sites; it is also safe to use in patients who are too sick to be treated with conventional therapies. Preoperative PDT has reduced the extent of surgery necessary in some patients. Clinical experience with PDT for gynecological cancer is limited and prospective studies are needed. In head and neck oncology, PDT should prove a useful option, but methodological problems need to be overcome. Good responses of esophageal cancer to PDT have led to governmental approval of Photofrin, a photosensitizer, in several countries for either palliative use or treatment of inoperable or recurrent cancer. The use of PDT for early gastric cancer has great potential but several technical problems remain. PDT has proven generally effective for skin cancer when hematoporphyrin derivative or Photofrin is used but more long-term follow-up data are required for PDT with 5-aminolevulinic acid. Overall, PDT is changing from a scientific curiousity into an accepted modality for the treatment of cancer, with an improved likelihood of finding further clinical applications.
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PMID:Photodynamic therapy: applications in bladder cancer and other malignancies. 940 16

Photodynamic therapy (PDT) is primarily suggested for the therapy of papillary transitional cell carcinoma (TCC) and refractory carcinoma in situ (CIS), and prophylaxis of recurrent superficial TCC in those patients who have failed intravesical chemotherapy or immunotherapy. We reviewed our 13-year experience to assess the long-term role of PDT in the management of superficial bladder cancer, and propose a standard protocol. Fifty eight patients underwent a single PDT treatment with 1.5-2.0 mg/kg of Photofrin and 10-25 J/cm2 of light (630 nm). This single PDT treatment produced overall response rates of 84.2% in 19 patients with recurrent superficial papillary TCC, 80% in 20 patients with refractory CIS, and 89.5% in 19 patients receiving prophylaxis. The PDT dose of 2.0 mg/kg and 15-25 J/cm2 produced the most durable tumor response at the expense of severe local morbidity. However, the PDT dose of 1.5 mg/kg and 10-15 J/cm2 yielded variable tumor responses, with minimal local morbidity. Overall our data confirm that PDT is an effective therapy for superficial bladder cancer. We recommend PDT as a second line or immediate therapy for BCG or chemotherapy failures using a standard PDT dose of 1.5 mg/kg of Photofrin and 15 J/cm2 (630 nm) and a scheduled repeat treatment with 1.5 mg/kg and 10 J/cm2 at 6 and 12 months.
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PMID:Photodynamic therapy in the management of bladder cancer. 961 93

Over the last decade, laser treatment of neoplastic diseases has become routine. The ability of these light-induced therapies to effect positive results is increased with the utilization of photosensitizing dyes. The approval of Photofrin in Canada as a first generation photodynamic therapeutic agent for the treatment of some forms of bladder cancer is being followed by the development of other agents with improved properties. At this time a number of second generation photosensitizing dyes are under study in phase I/II clinical trials. A review of the status of these trials along with mechanistic aspects is reviewed in this article. In addition, a review of the status of lasers to be utilized for photodynamic therapy gives some indication of which instruments could be considered for this therapy in the future.
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PMID:Second generation photodynamic agents: a review. 1014 14


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