- Lisbon, Portugal
- Peter Hofland, PhD
- Reuters Health
Temoporfin-mediated photodynamic therapy represents a major advance in the treatment of head and neck cancer, yielding complete response rates comparable with those published for surgery or radiotherapy, according to phase II data reported here last week during ECCO 11, the European Cancer Conference.
Temoporfin-mediated photodynamic therapy (Foscan PDT) is an “effective and well-tolerated treatment” and can be administered without surgery, said Dr. Colin Hopper, a consultant surgeon of the National Medical Laser Centre in London, UK. Dr. Hopper presented the results of a prospective non-randomised phase II study, conducted in 15 centers in 6 countries. The trial examined response rates to Foscan PDT in 114 patients with primary (Tis, T1 and T2) squamous cell carcinoma of the lip, oral cavity, oropharynx or hypopharynx.
Patients with Karnofsky status greater than or equal to 70 received Foscan (0.15 mg/kg IV), followed 4 days later by a single nonthermal illumination of the tumor with red light (20 J/cm?, irradiance 100 mW/cm? , wavelength 652 nm). The initial response was determined after 12 weeks. After 2 years of follow-up, 85% of patients had a complete response (elimination of the tumor) with Foscan PDT alone, and another 6% achieved a complete response with Foscan PDT followed by other adjunctive therapy, including surgery or radiotherapy, giving an overall response rate of 91%. Dr. Hopper reported that in 59% of all cases a complete response rate was biopsy-confirmed. The 1- and 2-year overall survival rates were 90% and 81% respectively, he said. There were 23 non-fatal serious adverse events of which only 5 were related to the treatment (two burns, one photosensitivity reaction, one excessive tissue necrosis, and one increase in pain and dysphagia). Twelve patients died during the first year, but their deaths were not associated with the treatment, the British researcher said. Dr. Hopper explained that “these response rates are comparable to those published for surgery or radiotherapy, but photodynamic therapy has the advantage of not being associated with the major toxicity of radiotherapy nor the tissue loss associated with surgery. It produces excellent cosmetic results, preserving form and function, and does not compromise future treatment options for recurrent, residual or second primary disease.” This is particularly important, because there is a significant risk in head and neck cancer that another cancer will develop at or near the original site, and will require such treatment, he noted.
The most common adverse event noted was local pain at the treatment site, but according to the physicians involved in the study, “this can be managed with standard analgesic treatment.”