Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0024623 (gastric cancer)
 36,219 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

Porfimer sodium (Photofrin II) is a photosensitizer which distributes selectively to tumor tissues, and causes tumor cell death by combination with light irradiation. Photodynamic therapy (PDT) by combination of porfimer sodium and laser was developed as a new cancer therapy. Tumor selectivity of porfimer sodium are based on the following reasons; 1) high affinity for lipoprotein, especially, low density lipoprotein (LDL), 2) elevation of LDL receptor activity in cancer tissue, and 3) lack or imcompleteness of lymphatic system in cancer tissue. Porfimer sodium is activated by laser irradiation at 630 nm, which can reacts with tissue oxygen to produce highly reactive excited siglet oxygen (1O2). This highly reactive molecule is subsequently capable of killing tumor cells through oxidation of cellular component like mitochondrial enzymes. In addition, this highly reactive intermediate causes destruction of the tumor capillaries, which accelerates tumor cell death. The growth suppression or lethal damage to tumor cells by PDT of porfimer sodium and excimer dye laser were observed in experimental tumor models. In human clinical trials, the rates of complete response (CR) for roentgenographically occult lung cancer, stage I lung cancer, superficial esophageal cancer, superficial gastric cancer and carcinoma in situ or dysplasia of the cervix were 84.8%, 50.0%, 90.0%, 87.5% and 94.4%, respectively. The major side effects were cutaneous symptoms e.g. photosensitivity, pigmentation, increasing GOT, GPT but these symptoms were not severe. PDT using porfimer sodium and excimer dye laser must be clinically useful for the treatment of inoperable early cancer or conservation of organ functions.
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PMID:[Porfimer sodium (Photofrin-II)]. 766 80

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

In this article, we first present our clinical data on PDT for the treatment of gastric cancer and make a comparison between a continuous wave laser and a pulsed laser. The reasons for PDT failure in certain cases are also discussed. In the fifteen years from 1981 to 1995, we have treated a total of 76 gastric cancer lesions (73 cases), which was consist of 69 early gastric cancer lesions (66 cases) and seven advanced gastric cancer lesions (seven cases) by PDT. From 1981 to 1990, we used an argon dye laser (ADL, Models 171-08 and 375-03, Spectra-Physics, Mountain View, Calif., US) as an excitation light source for PDT with HpD (Photofrin I), DHE (Photofrin II) or PHE (freeze-dried Photofrin II). From analysis of the results in terms of the depth of cancer invasion in these 44 lesions (41 cases), the rate of cure for mucosal carcinomas was 57% (13/23), that of submucosal carcinomas was 53% (10/19), and that of carcinomas invading more than the muscularis propria was 0% (0/2). These data can be interpreted to indicate that the ADL laser beam could not penetrate and supply sufficient energy to activate HpD not only in the submoucosal layer but also in the mucosal layer. In 1990, therefore, we investigated an excimer dye laser (EDL, Hamamatsu Photonics, Hamamatsu, Japan), because its pulsed beam with extremely high peak power was expected to be more efficient at exciting HpD than continuous wave lasers such as ADL and high frequency pulsed lasers such as cooper vapor dye laser (Cu VDL). From 1990 to 1995, twenty-seven early gastric cancer lesions (27 cases) and five advanced gastric cancer lesions (five cases) were treated by PDT with EDL and PHE. Of these 32 lesions, the rate of cure for mucosal carcinomas was 100% (15/15), that of submucosal carcinomas was 75% (9/12), and that of carcinomas invading more than the muscularis propria was 20% (1/5). For the purpose of determining how much energy was required for a complete cure in early gastric cancer, and to compare the efficacy of ADL and EDL, the relation between the response (cure or no cure) and irradiated energy intensity (dose: J/cm 2) was evaluated by the depth of cancer invasion and kind of laser used in PDT. A smaller EDL dose was more effective than ADL in terms of photodynamic action.
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PMID:[Photodynamic therapy for gastric cancer]. 854 68

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

Endoscopic photodynamic therapy (PDT) using a pulsed gold vapor laser (wavelength 628 nm, LaserSonics Inc.) was performed on eight cases of early gastric cancer. Three patients refused to have surgery, and the others were in a high-risk group due to old age or complications with other diseases. Hematoporphyrin derivative (HpD I, 2.5-3 mg/kg, Photofrin Inc.) was injected intravenously, and 48-72 hours later, the entire cancer lesion and 5 mm width mucosa encircling it were irradiated with a gold vapor laser through a single quartz fiber. The irradiation was delivered at 300-330 mW for 5-20 minutes, which gave about 90 J/cm 2 dosage. In seven of eight cases, local cure was achieved. Recurrence was noted only in one patient. In one of eight patients, operation was carried out 1 month after PDT. Pathological examination of the resected stomach revealed that the effect of PDT extended into the tunica muscularis propria. Side effects of HpD, such as skin rash, were noted in two patients, but no serious complications of PDT were encountered. This suggests that PDT with a pulsed gold vapor laser is clinically useful in the treatment of early gastric cancer.
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PMID:Photodynamic therapy for early gastric cancer using a pulsed gold vapor laser. 1014 58

Photodynamic therapy (PDT) has been established as a potent and less invasive treatment for gastrointestinal tumors. The aim of the present study was to investigate whether or not liposomalization of the photosensitizer enhanced the therapeutic efficacy of PDT. Photofrin (PF) was entrapped in multilammelar liposomes. Mice implanted with a human gastric cancer xenograft, were divided into a PF group and a liposomal photofrin (LPF) group and intravenously administered 10 mg/kg of PF or LPF (as a dose of PF), respectively. At 8 h after injection PF level in tumor tissue in the LPF group was significantly higher level by 2.4-fold of that in the PF group, whereas the PF levels in the skin were almost equal. Irradiation was performed with the excimer dye laser at 150 mW/cm(2), total dose 40 J, at 8 h after PF or LPF administration. The results revealed that the volume of necrotic tumor tissue was significantly higher in the LPF group than in the PF group. The apoptotic index of the tumor was also significantly higher in the LPF group. In conclusion, the liposomalization of the photosensitizer increased its tumor accumulation, with a resulting enhancement of the therapeutic effect of PDT.
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PMID:Liposomal photofrin enhances therapeutic efficacy of photodynamic therapy against the human gastric cancer. 1458 Nov 65

The aim of this study was to investigate the mechanism of cell death by photodynamic therapy (PDT) in the gastric cancer cell line MKN45 with focus on the mechanism of apoptosis. Gastric cancer cells (MKN45) were incubated with Photofrin for up to 24 h before exposure to He-Cd laser (441 nm, 1 J/cm2). Cell viability was assessed by the methyl-tetra-zolium assay after exposure to light. A 95% cell death (LD95) was measured with 10 microg/ml of Photofrin. DNA ladder formation and chromatin condensation were seen within 60 min. Caspase-3-like and caspase-9-like activities increased from 15 min after exposure to light. Reduction of rhodamine 123 uptake started at 30 min. Caspase-inhibitor VAD-fmk (10 mM) inhibited apoptosis, but did not influence cell viability. In conclusion, Photofrin-mediated PDT in the gastric cancer cell line MKN45 induces apoptosis within 60 min, and mitochondrial damage is likely as the first event of apoptosis.
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PMID:Apoptosis of gastric cancer cell line MKN45 by photodynamic treatment with photofrin. 1533 43