Fig 4. IVT topotecan preferentially slows leptomeningeal tumor growth in brains versus spines.

Bioluminescence of brains and spines calculated at each time point up to the first death in each group. Shown: mean ± SEM for each group. (A) Ratios of spine-to-brain radiance measurements illustrate the relatively-faster increase in spine radiance compared to brain radiance in IVT TPT groups compared to the non-IVT groups. (B) Brain radiance measurements reveal more effective suppression of tumor growth in brains of TPT IP mice compared to saline IP in brains of TPT IVT (bolus or pump) mice compared to TPT IP and in brains of TPT IVT bolus mice compared to TPT IVT pump. (C) Spine radiance measurements reveal more effective tumor growth suppression in spines of TPT IVT bolus mice compared to TPT IP mice. There was a trend toward significance in spines of mice treated with TPT IVT bolus compared to TPT IVT pump, but it did not reach significance levels. p-values were calculated for each two groups using unpaired t-tests at each of the time points.