MTHPC Mediated Interstitial Photodynamic Therapy of Recurrent Nonmetastatic Base of Tongue Cancers: Development of a New Method

Background: Interstitial photodynamic therapy (iPDT) can be an option in the management of locally recurrent base of tongue cancer after (chemo)radiation treatment. The purpose of the current study was to develop a technique to implant light sources into the tumor tissue.

Methods: Twenty patients with previously irradiated locally recurrent base of tongue cancers who were not candidates for salvage surgery or reirradiation or refused these therapies were included in this study. The treatment planning was done on MRI. The light sources were implanted using modified brachytherapy techniques.

Results: The iPDT could be conducted in all patients without short-term complications. At 6 months, 9 patients had complete response with 4 patients still free of disease (46-80 months). Long-term complications included pharyngocutaneous fistula in 6 patients, serious bleeding in 1 patient, and cutaneous metastasis in 2 patients.

Conclusion: The initial results are encouraging. There is room for improvement to control the destructive potential of iPDT through planning and monitoring tools.