Cranial irradiation increases tumor growth in experimental breast cancer brain metastasis

Abstract

Whole‐brain radiotherapy is the standard of care for patients with breast cancer with multiple brain metastases and, although this treatment has been essential in the management of existing brain tumors, there are many known negative consequences associated with the irradiation of normal brain tissue. In our study, we used in vivo magnetic resonance imaging analysis to investigate the influence of radiotherapy‐induced damage of healthy brain on the arrest and growth of metastatic breast cancer cells in a mouse model of breast cancer brain metastasis. We observed that irradiated, but otherwise healthy, neural tissue had an increased propensity to support metastatic growth compared with never‐irradiated controls. The elucidation of the impact of irradiation on normal neural tissue could have implications in clinical patient management, particularly in patients with residual systemic disease or with residual radio‐resistant brain cancer.

Magnetic microspheres can be used for magnetic particle imaging of cancer cells arrested in the mouse brain

“…Areas containing SPIO-labeled cells appear as regions of low signal intensity (signal voids) on MRI images, creating negative contrast. Many different cell types have been prelabeled with iron particles and tracked with MRI, including mesenchymal stem cells, 5,6 progenitor cells, 7 dendritic cells, [8][9][10] cancer cells, [11][12][13] and pancreatic islets. 14 This technique is highly sensitive, permitting the imaging of single cells in vivo, 15,16 under ideal conditions.…”

Radiotherapy in Preclinical Models of Brain Metastases: A Review and Recommendations for Future Studies

“…Premature PCI interventions may even promote tumor progression and metastatic formation by inducing alterations in the brain microenvironment. For instance, administering RT (10 Gy/1F) seven days before injection results in damage to normal brain tissue, which becomes more susceptible to the growth of BM 51 . The relevant parameters of the PCI research are detailed in Table 5 .…”

“…Various methods are employed for the establishment of AM-BMs including intracerebral [33,39,[41][42][43][44][45][46][47][48][49][50] , intracardiac [31,32,[51][52][53][54] , carotid artery [55] and tail vein injection [56,57] . Few studies have explored spontaneous [58] or induced AM-BM [58,59] .…”

“…For intracerebral inoculation modeling, SRS [42,72,73] or WBRT [30,33,37,38,45,46,49,74,75] were commonly applied. Arterial inoculation-constructed AM-BM often involves WBRT [31,32,[51][52][53][54][55] . Additionally, PCI is used for AM-BMs established through intravenous (IV) inoculation via tail vein injection [56,57] .…”