Photodynamic therapy adjuvant to surgery in metastatic carcinoma in brain

Summary 

Cerebral metastases occur in 15–40% of cancers and their incidence is increasing. We have studied the use of fluorescence image-guided surgery and repetitive photodynamic therapy in 14 metastatic brain cancers.

Methods

Case note review of prospectively collected data on patients who were treated with PDT at the time of surgery for brain metastases. Patients were consented for the surgery and PDT. Patients were given 2mg/kg body weight of Photofrin^® IV 48h before the surgery and 20mg/kg 5-aminolevulenic acid orally 3h before surgery. Following resection of the tumor using fluorescence, microsurgical and image guidance techniques, the post-excision cavity is filled with a balloon using 0.32% intralipid solution and up to five consecutive PDT treatments were given using 100J/cm² Diode Laser 630nm. Patients were followed up clinically and by brain imaging every 3 months till their death.

Results

Seven were lung in origin and seven of variable sources. One patient with lung metastases died of unrelated cause while the remaining six had remained free from brain disease till their death. Two of the remaining seven patients died of local brain recurrence, one bowel after 4 weeks and one of unknown primary after 70 weeks.

Conclusion

Adjuvant repetitive PDT seems to offer an excellent local control of metastatic brain carcinomas with about 79% of patients succumb to the primary and only two out of fourteen died of brain recurrence with the best results obtained in lung cancer.

Abbreviations: ALA, 5-aminolevulenic acid, CT, chemotherapy, FGR, fluorescence guided resection, h, hours, IV, intravenous, PD, photodiagnosis, PDT, photodynamic therapy, PO, orally, SRS, stereotactic radiosurgery, TTR, time to tumor relapse, WBRT, whole brain radiotherapy

Keywords: Matastatic brain carcinomas, Fluorescence guided resection, Photodynamic therapy