Photodynamic therapy (
PDT) is an effective
cancer treatment modality that allows selective destruction of malignant
tumor cells. We asked whether
PDT could inhibit in vivo and in vitro growth of
synovial sarcoma cells. We analyzed
PDT using ATX-S10.Na(II) and a
diode laser for a
synovial sarcoma cell line (SYO-1).
Photodynamic therapy with ATX-S10.Na(II) showed an in vitro cytotoxic effect on the cultured SYO-1 cells. The in vitro effect of
PDT depended on the treatment concentration of ATX-S10.Na(II) and the
laser dose of irradiation. ATX-S10.Na(II) was detected in the
tumor tissue specimens that were excised from nude mice bearing SYO-1 within 6 hours after
intravenous injection, but it was eliminated from the
tumor 12 hours after injection.
Photodynamic therapy suppressed the
tumor growth of nude mice bearing SYO-1, and high-dose irradiation induced no viable
tumor cells in histologic specimens.
Photodynamic therapy performed after marginal resection of the
tumor of nude mice bearing SYO-1 reduced the rate of local recurrence of the
tumor. Our results suggest
PDT using ATX-S10.Na(II) and
laser irradiation may be a potentially useful treatment for
synovial sarcoma, especially to reduce the
surgical margin and preserve critical anatomic structures adjacent to the
tumor.