title: Effect of photodynamic therapy using 5-aminolevulinic acid on 4-nitroquinoline-1-oxide-induced premalignant and malignant lesions of mouse tongue.
abstract: A new photosensitizing agent 5-aminolevulinic acid (ALA)-based photodynamic therapy (PDT) has been demonstrated as a useful method for treatment of superficial neoplastic lesions. The aim of this study was to determine the effects of topically and systemically ALA-based PDT in neoplastic lesions of the oral cavity. Premalignant and malignant lesions of mouse tongue induced by 4-nitroquinoline-l-oxide (4NQO) were used in this study. At 1, 2 and 3 h after topical application of ALA or 3 h after systemic administration of ALA (250 or 1000 mg/kg), the lesions were irradiated with Nd: YAG dye laser at 630 nm (200 J/cm2). Both premalignant and early malignant lesions showed complete response to systemically ALA-based PDT. In an invasive nodular malignant lesion, however, only the superficial portion was affected. There was no apparent difference in the PDT effect between 250 and 1000 mg/kg doses of ALA. In contrast, topically ALA-based PDT had virtually no effect on most lesions. It was concluded that systemically ALA-based PDT is a useful method for treating premalignant and early malignant lesions in the oral cavity, while topically ALA-based PDT using this preparation may be unsuitable for treatment of oral lesions.
authors.affiliation: Second Department of Oral and Maxillofacial Surgery, Nagasaki University School of Dentistry, Japan.
authors.forename: G
authors.initials: G
authors.lastname: Ma
authors.forename: H
authors.initials: H
authors.lastname: Ikeda
authors.forename: T
authors.initials: T
authors.lastname: Inokuchi
authors.forename: K
authors.initials: K
authors.lastname: Sano
mesh_terms: D015112:4-Nitroquinoline-1-oxide; D000622:Aminolevulinic Acid / Q000627:therapeutic use*; D000818:Animals; D002273:Carcinogens; D005455:Fluorescent Antibody Technique; D008297:Male; D051379:Mice; D008808:Mice, Inbred CBA; D010778:Photochemotherapy / Q000379:methods*; D017319:Photosensitizing Agents / Q000627:therapeutic use*; D011230:Precancerous Conditions / Q000139:chemically induced / Q000188:drug therapy*; D014062:Tongue Neoplasms / Q000139:chemically induced / Q000188:drug therapy*
chemical_list: D002273:Carcinogens; D017319:Photosensitizing Agents; D015112:4-Nitroquinoline-1-oxide; D000622:Aminolevulinic Acid