A Phase 1-2 study of high-dose photoradiation therapy was performed in 23 patients with cerebral tumors. Twenty-two patients had high-grade gliomas (13 glioblastomas, six recurrent glioblastomas, two anaplastic astrocytomas, and one recurrent anaplastic astrocytoma) and one had a right frontal metastasis from a carcinoma of the lung. Hematoporphyrin derivative was administered to these patients in a dose of 5 mg/kg and, 24 hours later, they all underwent a craniotomy with radical excision of the tumor. The tumor bed was then irradiated with 630 nm of laser light from either an argon dye laser or a gold metal vapor laser for between 43 and 94 minutes, receiving total doses of 70 to 120 J/sq cm (six cases) or 120 to 230 J/sq cm (17 cases). The temperature of the tumor bed was kept below 37 degrees C by irrigation. Fifteen patients who developed new tumors underwent postoperative radiotherapy (45 Gy in 20 divided doses). There was no evidence of increased cerebral edema and no other toxicity from the therapy. All patients were discharged from the hospital within 18 days of surgery. Four of seven patients with gliomas have suffered a further recurrence at 12 to 16 weeks, and two of 15 patients with primarily treated gliomas experienced recurrence at 3 and 13 months following therapy. Fifteen patients have had no recurrence of their tumor and are alive and well at a median follow-up period of 7 months (range 1 to 16 months). It is concluded that photoradiation therapy using 5 mg/kg of hematoporphyrin derivative and 630 nm light at doses of up to 230 J/sq cm can be used as an adjuvant to surgery and radiotherapy with no additional complications.