Abstract
The effectiveness of Gamma Knife (GK) treatment for multiple metastatic brain tumors was retrospectively reviewed. Among 170 cases with brain metastases of non-small cell (NSC) lung cancer treated in Chiba Cardiovascular Center and Chiba Cancer Center between April 1990 and August 1999, 95 consecutive patients were analyzed for this study, each meeting the following 4 criteria ; 1) up to 10 multiple brain lesions at initial diagnosis, 2) no surgically inaccessible tumors of ≩3cm in diameter, 3) no meningitis carcinomatosa, and 4) more than 2months of life expectancy. Patients were divided into two groups : GK group (51cases) and non-GK group (44cases). In the GK group we resected large tumors (≩3cm) and treated small lesions (<30cm) by GK radiosurgery. New lesions were treated by repeated GK therapy without prophylactic whole brain radiation therapy (WBRT). Patients in the non-GK group were treated by the traditional combined therapy of surgery, external fractionated brain radiation therapy, and chemotherapy. Intervals from the date of diagnosis to date of death, neurological death and impaired quality of life were longer in the GK group than in the non-GK group. The significant prognostic factors in the mono-variate analyses were control of systemic disease (high risk group : uncontrolled, p<0.0001), initial Karnofsky peformance scale score (<70, p=0.0269), treatment group (non-GK group, p=0.0032), chemotherapy (no, p=0.0303), and gender (male, p=0.0444), In multivariate analyses, significant prognostic factors were the control of systemic desease (high risk group : uncontrolled, p<0.0001), treatment group (non-GK group, p<0.0001), and the initial Karnofsky performance scale (<70, p=0.0050). GK radiosurgery combined with surgery following the repeated GK therapy without prophylactic WBRT could be one possible treatment for patients with up to 10 multiple metastatic brain tumors resulting from NSC lung cancer.
