The physiology of increased fluid pressure in tumors and its effect on intratumoral injection with Holmium-166(166HoPLLAMS)

Abstract

Purpose: To investigate the effect of increased interstitial pressure in tissue on the distribution of 165Ho microspheres after intratumoral injection. Material and methods: A dose of 10 mg 165Ho-PLLA-MS (Ø 10-20 μm) was injected in falcon tubes containing soft tissue and a calibrated pressure of respectively 0, 20, 40 and 80 mmHg. After injection Computed Tomography (CT) was conducted on the falcon tubes for visualization of the 165Ho-PLLA-MS. Two parameters, one for absolute spreading (area of view that contained holmium) and one for three dimensional spreading where established and calculated using ImageJ software to compare the difference of distribution between the four pressure groups. Results: Three dimensional spreading seems to be negatively influenced by an increase of pressure although no significant difference could be made. Absolute spreading seems not to be influenced by different pressure values. Conclusion/ discussion: No difference can yet be made on the effect of increased pressure in tissue on the distribution of holmium microspheres. More research and other models are possible needed to prove a difference.