Skull Base Surgery of the Posterior Fossa

© Springer International Publishing AG 2018 177
W.T. Couldwell (ed.), Skull Base Surgery of the Posterior Fossa,
https://doi.org/10.1007/978-3-319-67038-6_13

Metastasis to the Posterior Fossa

Bradley D. Weaver and Randy L. Jensen

Abbreviations

C1 First cervical vertebra
CSF Cerebrospinal fluid
CT Computed tomography
EGFR Epidermal growth factor receptor
EVD Extraventricular drain
GTR Gross total resection
iMRI Intraoperative MRI
KPS Karnofsky performance scale
LINAC Linear accelerator
LMD Leptomeningeal disease/dissemination
MRI Magnetic resonance imaging
PFS Posterior fossa syndrome
RPA Recursive partitioning analysis
SRS Stereotactic radiosurgery
WBRT Whole-brain radiotherapy

Introduction

Retrospective analyses have estimated the incidence

of brain metastasis among all cancer patients at or

over 30% [ 1 – 3 ]. The discovery of brain metastasis

in patients with previously diagnosed or as-yet-

undiagnosed cancer significantly changes the

prognosis and treatment options for these patients.

If the metastasis is left untreated, the patient’s sur-

vival is often measured in months; however, in

many cases, life span can be significantly extended

with treatment. Ultimately, brain metastases rep-

resent a far more common disease than primary

brain tumors, and their incidence is increasing [ 1 ].

This increase is thought to be largely due to

greater therapeutic control of extracranial disease,

which allows more time and opportunity for met-

astatic spread from marginally controlled sites

[ 4 ]. Improved brain imaging with expanded avail-

ability is also increasing discovery of solitary and

multiple metastases. The problem of metastatic

disease of the brain is thus one of the growing

interests to the neurosurgeon and neuro-oncologi-

cal teams, as improving therapies create larger

numbers of long-term survivors.

Metastasis to the Cerebellum

The most common cancers that spread to the

central nervous system parenchyma are the

lung, melanoma, genitourinary, and breast.

Approximately 10–15% of all brain metastases

are located in the cerebellum or posterior

B.D. Weaver, BS (*)
University of Utah School of Medicine,
Salt Lake City, UT, USA

Department of Oncological Sciences, Huntsman
Cancer Institute, Salt Lake City, UT, USA
e-mail: [email protected]

R.L. Jensen, MD, PhD
Department of Oncological Sciences, Huntsman
Cancer Institute, Salt Lake City, UT, USA

Department of Radiation Oncology, Huntsman
Cancer Institute, Salt Lake City, UT, USA

Department of Neurosurgery, Clinical Neurosciences
Center, University of Utah, Salt Lake City, UT, USA
e-mail: [email protected]

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