Additional Photodynamic Therapy Research Articles

Photodynamic Therapy of Cholangiocarcinoma Cancer

Prognosis of nonresectable cholangiocarcinoma is not good, and in Bismuth type III and IV tumors relief of jaundice is seldom achieved, despite successful endoprosthesis insertion. Additional photodynamic therapy seems to be a promising new approach to these tumors. First pilot studies show relief of jaundice, mainly because of opening of the intrahepatic ducts and improvements in quality of life indices. Survival time seems to be long; however, randomized studies are necessary to confirm these results.

Effect of photodynamic therapy in a multimodal approach for advanced carcinoma of the gastro-esophageal junction.

Background and Objective We wanted to determine the role of additional photodynamic therapy in a multimodal approach for the treatment of patients with advanced cancer of the gastro-esophageal junction. Study Design/Materials and Methods We reviewed 53 patients, after endoluminal palliation, with advanced cancer of the gastro-esophageal junction. Combined dilatation and retrograde tumor disobliteration with Nd-YAG laser before photodynamic therapy (PDT), brachyradiotherapy, or both, became necessary in 12 patients. Brachyradiotherapy was carried out in all patients. PDT before brachyradiotherapy was performed in 25 patients. The endoluminal treatment was completed by external beam irradiation in 30 patients (15 cases with PDT and 15 without PDT) with an at least fair performance status. Photodynamic therapy showed a significant difference regarding the mean opening of the tumor stenosis (mean, 6.4 mm; P = 0.0002), the mean decrease in tumor length (3.1 cm; P = 0.00001) and the increase in median survival (13. 8 months; P = 0.001). The combined multimodal approach by using PDT, brachyradiotherapy and external beam irradiation showed a median survival of 16.8 months. However, additional external beam irradiation showed no significant difference (P = 0.11). The rate of severe complications was 5.7%. The mortality rate was 1.9%. Photodynamic therapy has been shown to be an effective treatment for palliation of advanced cancer at the gastro-esophageal junction. The use of PDT combined with irradiation was associated with an acceptable survival rate, low rates of complications and reasonable quality of life.

M‐THPC‐Mediated Photodynamic Therapy (PDT) Does Not Induce Resistance to Chemotherapy, Radiotherapy or PDT on Human Breast Cancer Cells In Vitro

Photodynamic therapy (PDT) uses laser light to activate a photosensitizer that has been absorbed preferentially by cancer cells after systemic administration. A phototoxic reaction ensues resulting in cell death and tissue necrosis. Some cells, however, may survive PDT. This study was performed to determine if surviving human breast cancer cells (MCF-7) can become resistant to PDT, chemotherapy or radiotherapy. The MCF-7 cells were cultured under standard conditions prior to being exposed to the photosensitizer, 5,10,15,20-meta-tetra(hydroxyphenyl)chlorin (m-THPC), for 24 h and then irradiated with laser light (652 nm). Surviving cells were allowed to regrow by allowing a 2 week interval between each additional PDT. After the third and final treatment, colony formation assays were used to evaluate the sensitivity of cultured cells to ionizing radiation and PDT and the ATP cell viability assay tested in vitro chemosensitivity. Flow cytometry was used to analyze the cell cycle. No alterations in the cell cycle were observed after three cycles of PDT with m-THPC. Similar responses to chemotherapy and ionizing radiation were seen in control and treatment groups. The m-THPC-sensitized PDT did not induce resistance to subsequent cycles of PDT, chemo- or radiotherapy. Photodynamic therapy with m-THPC may represent a novel adjunctive treatment of breast cancer that may be combined with surgery, chemotherapy or ionizing radiation.

気管食道科領域における鏡視下手術 気道系 肺門部早期肺癌に対する光線力学的治療法

Photodynamic therapy utilizing Photofrin has proven to be effective in the treatment of a wide variety of solid tumors and luminal cancers. The effectiveness of photodynamic therapy (PDT) was demonstrated at our institution in 1980 for the treatment of lung cancers, and increasing attention has been focused on this new treatment technique since then. Over the past decade, 211 patients (253 lesions) with central type lung cancer have been treated in our hospital. In the early stage central-type of lung cancer cases in this group, complete remission was obtained in 75 lesions out of 91 (82.4%); however, in 16 of those the entire extent of the lesion could not be seen endoscopically. These cases were therefore given additional radiother- apy or surgical resection to prevent recurrence. Recurrence was recognized in a total of 6 lesions (6.6%), which were then treated by surgery and additional PDT. Fifty three patients were disease free from 5 to 176 months postoperatively; however, 6 patients died as a result of their lung cancer. We conclude that PDT is efficacious in the treatment of superficial lung cancer where complete remission may sometimes be achieved.