Vol.102 No.11 contentsPRACTICA OTO-RHINO-LARYNGOLOGICA
Vol. 102 No. 11 November 2009
Photodynamic Therapy and Photodynamic Diagnosis
for Head and Neck Cancer
Tomoyuki Yoshida
(Tokyo Medical University Hachioji Medical Center)
Photodynamic therapy (PDT) is recognized as one of the treatment options for early stage cancers. This treatment is a first-line treatment for carcinoma based on a photochemical reaction in which a photosensitizer is excited by laser irradiation, causing selective death of tumor tissue. PDT greatly differs from other cancer treatments particularly because the function of organs and tissues can be preserved. We have applied the PDT using porfimer sodium activated with an excimer dye laser for head and neck cancer since 1988 and have reported the results. Since 2003, PDT using NPe6 which was synthesized from the extract from chlorophyll and activated with a diode laser, has been applied in head and neck cancer patients. Furthermore, we proved the remaining NPe6 concentration in tumor tissue was about 2 to 5 times higher than that in normal tissue in human subjects. Having already treated 100 or more cases of the head and neck cancer, we consider early stage cancer of the larynx, the tongue, mouth and oropharynx as good target indications for PDT.
According to the latest treatment results of laryngeal cancer, rate of the complete remission (CR) and recurrence rates were 100％ and 9.1％, respectively, and as for tongue, mouth and oropharynx cancer, the CR and recurrence rates were 100％ and 8.0％, respectively, which are almost comparable with conventional treatments. No adverse experience/event was seen in terms of critical photosensitivity and blood biochemical toxicity. The pain associated with medical treatment was also slight and controllable by internal use of NSAIDs only, the healing process was also good and ingestion was possible from the first post-treatment day.
PDT is a cancer treatment method which could be associated with same-day surgery, or a short-term hospital stay.
Moreover, PDT has relevance for head and neck cancer patients not only as one of the treatment options for early stage cancer patients but also as a potential application to improve patients' QOL, by decreasing the tumor size, in those patients whose tumors are inoperable, or in cases treated using combination therapy with radiation and surgery.
Key words :photodynamic therapy, photodynamic diagnosis, head and neck cancer, early stage cancer