An important rule for excising brain tumors: cut precisely along the margin so as not to damage healthy tissue while removing the cancerous stuff. Wealthy modern hospitals have access to intra-operative MRI that helps neurosurgeons see the high vascularization of tumors as they work on the brain. But some surgeons resort to using their hands to feel for the difference between the healthy and diseased tissue, an incredibly subjective way of localizing where to cut.
A collaboration between researchers at Georgia Tech and Children’s Healthcare of Atlanta has led to the development of special nanoparticles made out of fat that contain Evans Blue dye. By injecting these nanoparticles into rats with glioma tumors, the liposomal nanoparticles found their way to the tumors and leaked the dye so as to stain the diseased tissue.
From the study abstract in Drug Delivery and Translational Research:
To assess tumor staining, tissue samples were analyzed visibly and using fluorescence microscopy. Area, perimeter ratios, and Manders overlap coefficients were calculated to quantify extent of staining. Nano-EB clearly marked tumor margins in the invasive tumor model. Area ratio of nano-EB staining to tumor was 0.89 ± 0.05, perimeter ratio was 0.94 ± 0.04, Manders R was 0.51 ± 0.08, and M1 was 0.97 ± 0.06. Microscopic tumor border inspection under high magnification verified that nano-EB did not stain healthy tissue. Nano-EB clearly aids in distinguishing tumor tissue from healthy tissue in an invasive tumor model, while injection of unencapsulated EB results in false identification of healthy tissue as tumor due to diffusion of dye from the tumor into healthy tissue.
Study in Drug Delivery and Translational Research: Evans blue nanocarriers visually demarcate margins of invasive gliomas
Press release: New Nanotechnology Research Study Turns Brain Tumors Blue