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

HpD photodynamic therapy (PDT) was performed on 4 patients with superficial esophageal cancer, 20 patients with 22 early gastric cancer lesions and one patient with advanced gastric cancer. About 50 h before irradiation, 3 mg/kg of HpD or 1.3-2.5 mg/kg of Photofrin II was injected intravenously. The entire lesion including a 5-mm border of normal surrounding mucosa, was irradiated with an argon dye laser at 630nm wavelength with an output of 100-400mW at the tip of the fiber. Complete response (CR) to HpD-PDT was obtained in 2 of 2 mucosal esophageal cancers, and one of 2 submucosal lesions, totalling 3 of 4, and in 13 of 13 mucosal gastric cancers and 7 of 9 submucosal lesions totalling 20 of 22. The depths of cancer involvement were determined endoscopically. In Borrmann 1 lesion with muscularis externa involvement, in spite of two trials with HpD-PDT, only partial response (PR) was obtained. Tumor laser dose had to be more than 90 J/cm2, and in several cases combined hot biopsy with electrodiathermy and/or repeated HpD-PDT was needed to obtain CR. HpD-PDT is indicated for superficial esophageal cancer and depressed and/or assembled protuberant-type of early gastric cancer with poor risk.
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PMID:[Indications for and limitations of HpD photodynamic therapy for esophageal cancer and gastric cancer]. 338 14

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

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