Efficacy and limitations of salvage gamma knife radiosurgery for treating brain metastases of small-cell lung cancer after whole-brain radiotherapyKiyoshi Nakazaki1, Osamu Nagano2, Yoshinori Higuchi2, Toru Serizawa31Hiroshima, Japan 2Chiba, Japan 3Tokyo, Japan Keywords: lung cancer, radiotherapy, gamma knife, radiosurgery, brain metastasis
Radiosurgery is increasingly being used in small cell lung cancer to the brain.
This study aimed to evaluate the efficacy of salvage gamma knife radiosurgery (GKS) for treating brain metastases of small-cell lung cancer (SCLC) in patients receiving whole-brain radiotherapy (WBRT) as the first radiation therapy.
Forty-seven patients with recurrent or new brain metastases of SCLC after WBRT received GKS between January 1999 and March 2011. Of these, 44 patients with recurrent or new SCLC-associated brain metastases underwent GKS after receiving WBRT as first-line radiation therapy and could be evaluated (35 men and 9 women; median age, 62 years; median duration between WBRT and the first GKS procedure, 8.8 months). The median Karnofsky performance status (KPS) score was 100 (range, 40–100). The median number of brain metastases at the first GKS was 5 (range, 1–98). Five patients had carcinomatous meningitis. Ten patients received prophylactic cranial irradiation (PCI) for limited disease
We reviewed our clinical and imaging data.
The median prescribed dose and number of lesions treated using the first GKS procedure were 20.0 Gy and 3.5, respectively, and the tumor control rate, 95.8% (mean follow-up period, 4.0 months). The 6-month new lesion-free survival, functional preservation rates, and overall survival were 50.0%, 94.7%, and 5.8 months, respectively. Neurological death occurred in 17.9% cases. The poor prognosis factors for new lesion-free survival time and functional preservation were >5 brain metastases and carcinomatous meningitis, respectively. Poor prognostic factors for survival time were KPS < 70, >10 brain metastases, diameter of the largest tumor > 20 mm, and carcinomatous meningitis. Median overall survival time after brain metastasis diagnosis was 16.9 months. The poor prognostic factor for a longer survival after brain metastases diagnosis was PCI.
This was a retrospective series.
GKS is effective for controlling SCLC-associated brain metastases after WBRT, and for preventing neurological death in patients without carcinomatous meningitis.
Salvage radiosurgery for small cell lung cancer after prior WBRT can be effective. Project Roles:
K. Nakazaki (), O. Nagano (), Y. Higuchi (), T. Serizawa ()