title: Clinical outcome of a novel photodynamic therapy technique using acridine orange for synovial sarcomas.
abstract: Synovial sarcoma (SS) is one of common malignant soft-tissue tumors and is encountered most commonly in children and young adults. It frequently involves or invades major neurovascular structures and bones, and its local recurrence rate after simple resection has been reported to be as high as up to 80%. Because major nerves and vessels, as well as an adequate amount of bone, must be preserved to restore excellent limb function in cases of SS, a surgical technique entailing a low risk of local recurrence is needed. Based on the findings of recent experimental studies conducted by us using a mouse osteosarcoma model, we developed a novel therapeutic technique for SS, consisting of reduction surgery followed by photodynamic therapy using acridine orange (AO-PDT), with or without X-ray irradiation at 5 Gy. A preliminary study revealed that low-dose X-rays also excite AO like photons. After an initial study on cell cultures, this novel technique was applied to six cases of SS. A follow-up of the subjects to determine the clinical outcome revealed that none of the cases treated by AO-PDT, including the four cases treated by additional 5 Gy irradiation and the two cases not receiving any radiation, showed any evidence of recurrence or local/systemic complications during the follow-up period of 19-51 months after the surgery. Therefore, we believe that AO-PDT with 5 Gy irradiation may be an excellent novel therapeutic modality with reduction surgery to salvage excellent limb function in SS involving major nerves and vessels or bones.
authors.affiliation: Department of Orthopaedic Surgery, Mie University Faculty of Medicine, Mie Prefecture, Japan. kusu@clin.medic.mie-u.ac.jp
authors.forename: Katsuyuki
authors.initials: K
authors.lastname: Kusuzaki
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Murata
authors.forename: Takao
authors.initials: T
authors.lastname: Matsubara
authors.forename: Shinichi
authors.initials: S
authors.lastname: Miyazaki
authors.forename: Ken
authors.initials: K
authors.lastname: Shintani
authors.forename: Masashi
authors.initials: M
authors.lastname: Seto
authors.forename: Akihiko
authors.initials: A
authors.lastname: Matsumine
authors.forename: Hajime
authors.initials: H
authors.lastname: Hosoi
authors.forename: Touru
authors.initials: T
authors.lastname: Sugimoto
authors.forename: Atsumasa
authors.initials: A
authors.lastname: Uchida
mesh_terms: D000165:Acridine Orange / Q000627:therapeutic use*; D000293:Adolescent; D000328:Adult; D000818:Animals; D002648:Child; D003131:Combined Modality Therapy; D004195:Disease Models, Animal; D005260:Female; D006801:Humans; D023821:Limb Salvage / Q000379:methods; D008297:Male; D051379:Mice; D008875:Middle Aged; D012516:Osteosarcoma / Q000378:metabolism / Q000601:surgery / Q000628:therapy*; D010789:Phototherapy; D011829:Radiation Dosage; D013584:Sarcoma, Synovial / Q000601:surgery / Q000628:therapy*; D016896:Treatment Outcome; D014407:Tumor Cells, Cultured; D014965:X-Rays
chemical_list: D000165:Acridine Orange