title: Radiosurgery for solitary brain metastases using the cobalt-60 gamma unit: methods and results in 24 patients.
abstract: To define the role of stereotactic radiosurgery in the treatment of metastatic brain tumors we treated 24 consecutive patients (20 men, 4 women) with the 201-source 60Co gamma unit between May 1988 and March 1990. The primary tumors included malignant melanoma (n = 10), non-small cell lung carcinoma (n = 6), renal cell carcinoma (n = 3), colorectal carcinoma (n = 1), oropharyngeal carcinoma (n = 1), and adenocarcinoma of unknown origin (n = 3). All tumors were less than or equal to 3.0 cm in greatest diameter. Twenty patients received a planned combination of 30-40 Gy whole brain fractionated irradiation and a radiosurgical "boost" of 16-20 Gy to the tumor margins; one patient refused conventional fractionated irradiation. Three patients with recurrent, persistent, or new non-small cell lung carcinomas had radiosurgical treatment 12-20 months after receiving 30-42.5 Gy whole-brain external beam irradiation. Stereotactic computed tomographic imaging was used for target coordinate determination and imaging-integrated dose planning. All tumors were enclosed by the 50-90% isodose shell using one (n = 22), two (n = 1), or three (n = 1) irradiation isocenters. During this 23-month period (median follow-up of 7 months) no patient died from progression of a radiosurgically-treated brain metastasis. Ten patients died of systemic disease (n = 8) or remote central nervous system metastasis (n = 2) between 1 week and 10 months after radiosurgery. One patient had tumor progression and underwent craniotomy and tumor excision 5 months after radiosurgery. To date, median survival after radiosurgery has been 10 months; 1-year survival was 33.3%. Stereotactic radiosurgery eliminated the surgical and anesthetic risks associated with craniotomy and resection of solitary brain metastases. Radiosurgery also effectively controlled the growth of tumors considered "resistant" to conventional irradiation.
authors.affiliation: Department of Neurosurgery, Mayo Clinic, Rochester, MN 55905.
authors.forename: R J
authors.initials: RJ
authors.lastname: Coffey
authors.forename: J C
authors.initials: JC
authors.lastname: Flickinger
authors.forename: D J
authors.initials: DJ
authors.lastname: Bissonette
authors.forename: L D
authors.initials: LD
authors.lastname: Lunsford
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001932:Brain Neoplasms / Q000401:mortality / Q000532:radiotherapy / Q000556:secondary*; D002289:Carcinoma, Non-Small-Cell Lung / Q000401:mortality / Q000532:radiotherapy / Q000556:secondary; D002292:Carcinoma, Renal Cell / Q000378:metabolism / Q000532:radiotherapy / Q000556:secondary; D003037:Cobalt Radioisotopes / Q000627:therapeutic use*; D005260:Female; D005720:Gamma Rays; D006801:Humans; D007680:Kidney Neoplasms / Q000401:mortality / Q000532:radiotherapy; D008175:Lung Neoplasms / Q000401:mortality / Q000532:radiotherapy; D008297:Male; D008545:Melanoma / Q000401:mortality / Q000532:radiotherapy / Q000556:secondary; D008875:Middle Aged; D015996:Survival Rate
chemical_list: D003037:Cobalt Radioisotopes