Laser photoradiation therapy of cancer following hematoporphyrin sensitization.

Hematoporphyrin derivative-photoradiation therapy (HPD-PRT) of human malignancy has been performed on 267 tumor sites in 50 patients. Tumor response has been assayed at 24 hours and one month following treatment with 625-635 nm light from an argon laser-pumped dye laser. The majority of tumors treated were dermal breast cancer recurrences (21 cases), local recurrence of ENT squamous cell carcinomas (16 cases), and ENT cutaneous metastases of squamous cell carcinomas (9 cases). A 30-day favorable response was judged to be either complete regression of the tumor or reduction of tumor diameter by greater than 50%. The above categories of tumors had a combined favorable response of 81%. Appropriate dosimetry is discussed.