Stereotactic radiosurgery in the treatment of brain metastases: The current evidence

TY - JOUR

T1 - Stereotactic radiosurgery in the treatment of brain metastases

T2 - The current evidence

AU - Lippitz, Bodo

AU - Lindquist, Christer

AU - Paddick, Ian

AU - Peterson, David

AU - O'Neill, Kevin

AU - Beaney, Ronald

PY - 2014/2

Y1 - 2014/2

N2 - Chemotherapy has made substantial progress in the therapy of systemic cancer, but the phar-macological efficacy is insufficient in the treatment of brain metastases. Fractionated whole brain radiotherapy (WBRT) has been a standard treatment of brain metastases, but provides limited local tumor control and often unsatisfactory clinical results. Stereotactic radiosurgery using Gamma Knife, Linac or Cyberknife has overcome several of these limitations, which has influenced recent treatment recommendations. This present review summarizes the current literature of single session radiosurgery concerning survival and quality of life, specific responses, tumor volumes and numbers, about potential treatment combinations and radioresistant metastases.Gamma Knife and Linac based radiosurgery provide consistent results with a reproducible local tumor control in both single and multiple brain metastases. Ideally minimum doses of >18 Gy are applied. Reported local control rates were 90-94% for breast cancer metastases and 81-98% for brain metastases of lung cancer. Local tumor control rates after radiosurgery of otherwise radioresistant brain metastases were 73-90% for melanoma and 83-96% for renal cell cancer. Currently, there is a tendency to treat a larger number of brain metastases in a single radiosurgical session, since numerous studies document high local tumor control after radiosurgical treatment of >3 brain metastases. New remote brain metastases are reported in 33-42% after WBRT and in 39-52% after radiosurgery, but while WBRT is generally applied only once, radiosurgery can be used repeatedly for remote recurrences or new metastases after WBRT. Larger metastases (>8-10 cc) should be removed surgically, but for smaller metastases Gamma Knife radiosurgery appears to be equally effective as surgical tumor resection (level I evidence). Radiosurgery avoids the impairments in cognition and quality of life that can be a consequence of WBRT (level I evidence). High local efficacy, preservation of cerebral functions, short hospitalization and the option to continue a systemic chemotherapy are factors in favor of a minimally invasive approach with stereotactic radiosurgery.

AB - Chemotherapy has made substantial progress in the therapy of systemic cancer, but the phar-macological efficacy is insufficient in the treatment of brain metastases. Fractionated whole brain radiotherapy (WBRT) has been a standard treatment of brain metastases, but provides limited local tumor control and often unsatisfactory clinical results. Stereotactic radiosurgery using Gamma Knife, Linac or Cyberknife has overcome several of these limitations, which has influenced recent treatment recommendations. This present review summarizes the current literature of single session radiosurgery concerning survival and quality of life, specific responses, tumor volumes and numbers, about potential treatment combinations and radioresistant metastases.Gamma Knife and Linac based radiosurgery provide consistent results with a reproducible local tumor control in both single and multiple brain metastases. Ideally minimum doses of >18 Gy are applied. Reported local control rates were 90-94% for breast cancer metastases and 81-98% for brain metastases of lung cancer. Local tumor control rates after radiosurgery of otherwise radioresistant brain metastases were 73-90% for melanoma and 83-96% for renal cell cancer. Currently, there is a tendency to treat a larger number of brain metastases in a single radiosurgical session, since numerous studies document high local tumor control after radiosurgical treatment of >3 brain metastases. New remote brain metastases are reported in 33-42% after WBRT and in 39-52% after radiosurgery, but while WBRT is generally applied only once, radiosurgery can be used repeatedly for remote recurrences or new metastases after WBRT. Larger metastases (>8-10 cc) should be removed surgically, but for smaller metastases Gamma Knife radiosurgery appears to be equally effective as surgical tumor resection (level I evidence). Radiosurgery avoids the impairments in cognition and quality of life that can be a consequence of WBRT (level I evidence). High local efficacy, preservation of cerebral functions, short hospitalization and the option to continue a systemic chemotherapy are factors in favor of a minimally invasive approach with stereotactic radiosurgery.

KW - Brain metastases

KW - Radiosurgery

KW - Treatment results

KW - Gamma Knife

KW - Linac

KW - GAMMA-KNIFE RADIOSURGERY

KW - RENAL-CELL CARCINOMA

KW - RECURSIVE PARTITIONING ANALYSIS

KW - QUALITY-OF-LIFE

KW - LOCAL TUMOR-CONTROL

KW - CANCER CLINICAL ARTICLE

KW - THERAPY ONCOLOGY GROUP

KW - LONG-TERM OUTCOMES

KW - CEREBRAL MELANOMA METASTASES

KW - RANDOMIZED CONTROLLED-TRIAL

U2 - 10.1016/j.ctrv.2013.05.002

DO - 10.1016/j.ctrv.2013.05.002

M3 - Literature review

SN - 0305-7372

VL - 40

SP - 48

EP - 59

JO - Cancer Treatment Reviews

JF - Cancer Treatment Reviews

IS - 1

ER -