Purpose: Because the effects of pirarubicin and carboplatin on the physical structure of particles made from polyvinylformaldehyde are not well known, we describe an experiment to test the in vitro polyvinylformaldehyde particle compatibility with these drugs used for chemoembolization of bone metastases.
Materials and methods: Polyvinylformaldehyde particles (Ultra-Drivalon) were mixed in vitro with either pirarubicin or carboplatin as experimental samples, and with distilled water as control samples, and left for 24 h at 37 degrees C. The particles used measured 150-250 microm and 600-1000 microm in diameter. Particle morphology, including appearance, overall shape, and surface characteristics were examined using a microscope equipped with a videocamera. Particle size was measured by granulometry. Qualitative and quantitative variables were analyzed using, respectively, the two-sided Fisher's exact test and the Wilcoxon signed rank test for paired values, with a significance level of 0.05.
Results: No broken particles or microscopic degradations in the appearance, overall shape, or surface characteristics of any particles were observed. The particle size distribution was not significantly different between the experimental samples containing pirarubicin or carboplatin and the control sample of particles with diameters in the same range.
Conclusion: Particles made from polyvinylformaldehyde can be mixed with pirarubicin or carboplatin without any risk of damaging their physical properties.