Metastasis infiltration: an investigation of the postoperative brain-tumor interface.
OBJECTIVE
This study aims to evaluate brain infiltration of metastatic tumor cells past the main tumor resection margin to assess the biological basis for the use of stereotactic radiosurgery treatment of the tumor resection cavity and visualized resection edge or clinical target volume.


METHODS
Resection margin tissue was obtained after gross total resection of a small group of metastatic lesions from a variety of primary sources. The tissue at the border of the tumor and brain tissue was carefully oriented and processed to evaluate the presence of tumor cells within brain tissue and their distance from the resection margin.


RESULTS
Microscopic assessment of the radially oriented tissue samples showed no tumor cells infiltrating the surrounding brain tissue. Among the positive findings were reactive astrocytosis observed on the brain tissue immediately adjacent to the tumor resection bed margin.


CONCLUSIONS
The lack of evidence of metastatic tumor cell infiltration into surrounding brain suggests the need to target only a narrow depth of the resection cavity margin to minimize normal tissue injury and prevent treatment size-dependent stereotactic radiosurgery complications.
Department of Neurological Surgery, Emory University, Atlanta, GA, USA.
Bethwel
B
Raore
Matthew
M
Schniederjan
Roshan
R
Prabhu
Daniel J
DJ
Brat
Hui-Kuo
HK
Shu
Jeffrey J
JJ
Olson
D001921:Brain / Q000473:pathology* / Q000601:surgery; D001932:Brain Neoplasms / Q000473:pathology / Q000532:radiotherapy / Q000556:secondary* / Q000601:surgery; D005911:Gliosis / Q000473:pathology; D006801:Humans; D009361:Neoplasm Invasiveness / Q000473:pathology*; D016634:Radiosurgery / Q000379:methods*; D047368:Tumor Burden