Management patterns of patients with cerebral metastases who underwent multiple stereotactic radiosurgeries

Abstract

With escalating focus on cost containment, there is increasing scrutiny on the practice of multiple stereotactic radiosurgeries (SRSs) for patients with cerebral metastases distant to the initial tumor site. Our goal was to determine the survival patterns of patients with cerebral metastasis who underwent multiple SRSs. We retrospectively analyzed survival outcomes of 801 patients with 3683 cerebral metastases from primary breast, colorectal, lung, melanoma and renal histologies consecutively treated at the University of California, San Diego/San Diego Gamma Knife Center (UCSD/SDGKC), comparing the survival pattern of patients who underwent a single (n = 643) versus multiple SRS(s) (n = 158) for subsequent cerebral metastases. Findings were recapitulated in an independent cohort of 2472 patients, with 26,629 brain metastases treated with SRS at the Katsuta Hospital Mito GammaHouse (KHMGH). For the UCSD/SDGKC cohort, no significant difference in median survival was found for patients undergoing 1, 2, 3, or ≥4 SRS(s) (median survival of 167, 202, 129, and 127 days, respectively). Median intervals between treatments consistently ranged 140-178 days irrespective of the number of SRS(s) (interquartile range 60-300; p = 0.25). Patients who underwent >1 SRSs tend to be younger, with systemic disease control, harbor lower cumulative tumor volume but increased number of metastases, and have primary melanoma (p < 0.001, <0.001, <0.001, 0.02, and 0.009, respectively). Comparable results were found in the KHMGH cohort. Using an independent validation study design, we demonstrated comparable overall survival between judiciously selected patients who underwent a single or multiple SRS(s).

Survival Patterns of 5750 Stereotactic Radiosurgery–Treated Patients with Brain Metastasis as a Function of the Number of Lesions

“…Radiosurgery was performed as previously described 19,20 . In brief, patients underwent Magnetic Resonance Imaging (MRI) of the brain with either the Toshiba America Medical Systems MRI machine (Tustin, California) at 2 mm slices or the GE Healthcare MRI machine (Milwaukee, Wisconsin) using 1 mm slices in conjunction with the Leksell stereotactic head frame.…”

Superior Prognostic Value of Cumulative Intracranial Tumor Volume Relative to Largest Intracranial Tumor Volume for Stereotactic Radiosurgery-Treated Brain Metastasis Patients

“…Details of these cohorts have been previously published. 18–20,22 In brief, every patient had a primary tumor confirmed outside of the central nervous system and underwent SRS without craniotomy. All patients were referred for SRS by a radiation or medical oncologist as well as a neurosurgeon.…”

“…Intracranial tumor volume is an important prognostic factor for SRS-treated BM patients. 17–20 The first prognostic scale to acknowledge the importance of intracranial tumor volume is termed Scored Index for Radiosurgery (SIR). SIR included 5 prognostic factors, including age, KPS, extracranial disease status, number of brain lesions, and volume of the largest intracranial tumor (LITV).…”

“…17 Our previous studies suggested that the cumulative intracranial tumor volume (CITV), or the sum volume of all intracranial metastases, may also serve as a critical prognostic factor for SRS-treated BM patients. 18–20 Here, we utilized the framework established by the SIR to test the prognostic performance of CITV relative to LITV.…”

A Case of Thymic Carcinoma with Bone and Cerebral Metastases Treated with Stereotactic Radiosurgery and Chemotherapy

“…A further important advantage of stereotactic radiosurgery is the preservation of neurocognitive function when compared with fractionated radiation of the entire cerebrum. Irradiation of normal cerebrum significantly affects neurocognitive function in a dose-dependent manner, while stereotactic radiosurgery reduces the decline in neurocognitive function, assuming that other treatment elements are favorable [15].…”