caa a22 4500 475790960 CHVBK 20180406123710.0 cr unu---uuuuu 170329e20000701xx s 000 0 eng 10.1007/s004230000140 doi (NATIONALLICENCE)springer-10.1007/s004230000140 Photodynamic treatment of neoplastic lesions of the gastrointestinal tract [Elektronische Daten] Recent advances in techniques and results [John Webber, Mark Herman, David Kessel, David Fromm] Photodynamic therapy (PDT) is a form of cancer treatment based on the selective accumulation of a photosensitizer (by exogenous or endogenous means) in neoplastic tissue. Subsequent activation of the photosensitizer by a specific wavelength of light results in tumor cell death. Activation of a photosensitizer to the appropriate energy state results in the production of singlet oxygen, a powerful oxidizing agent. PDT can kill cells by three mechanisms: direct cell death by photo-oxidation, apoptosis, or as a consequence of vascular shutdown. The toxicity of PDT is site specific and dependent on the organ being irradiated and the selectivity of the photosensitizer for target tissue over normal tissue. However, there are also reactions related to the sensitizer per se that are independent of those related to the treatment site. Such reactions include cutaneous photosensitization, nausea, vomiting, hypotension, and altered liver 'function' tests. Excitation of photosensitizer by an incident photon produces re-emission of a fluorescent photon, which can be used to detect a tumor that is not ordinarily evident. The major limiting factor in using PDT is the depth of tumor kill. The majority of clinical experience involving PDT of the gastrointestinal tract involves patients who are considered to be poor operative risks, and reported follow-ups after treatment are not only limited but also variable. Springer-Verlag, 2000 Photodynamic treatment Neoplastic lesions Gastrointestinal tract nationallicence Webber John Department of Surgery, 6C-University Health Center, 4201 St. Antoine, Wayne State University, Detroit, MI 48201, USA, USA aut Herman Mark Department of Surgery, 6C-University Health Center, 4201 St. Antoine, Wayne State University, Detroit, MI 48201, USA, USA aut Kessel David Department of Pharmacology, Wayne State University, Detroit, MI, USA, USA aut Fromm David Department of Surgery, 6C-University Health Center, 4201 St. Antoine, Wayne State University, Detroit, MI 48201, USA, USA aut Langenbeck's Archives of Surgery Springer-Verlag 385/4(2000-07-01), 299-304 1435-2443 385:4<299 2000 385 423 https://doi.org/10.1007/s004230000140 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s004230000140 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Webber John Department of Surgery, 6C-University Health Center, 4201 St. Antoine, Wayne State University, Detroit, MI 48201, USA, USA aut NATIONALLICENCE 700 1- Herman Mark Department of Surgery, 6C-University Health Center, 4201 St. Antoine, Wayne State University, Detroit, MI 48201, USA, USA aut NATIONALLICENCE 700 1- Kessel David Department of Pharmacology, Wayne State University, Detroit, MI, USA, USA aut NATIONALLICENCE 700 1- Fromm David Department of Surgery, 6C-University Health Center, 4201 St. Antoine, Wayne State University, Detroit, MI 48201, USA, USA aut NATIONALLICENCE 773 0- Langenbeck's Archives of Surgery Springer-Verlag 385/4(2000-07-01), 299-304 1435-2443 385:4<299 2000 385 423 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer