The three-dimensional vascular structures down to the smallest capillaries have been of vital interest in cancer research because of the demand for alternatives to the established treatments (surgery, medication and radiation). The present research efforts range from in vivo imaging (MRI, US, and PET), via post mortem methods, including micro computed computer tomography. In a previous study, we showed that synchrotron radiation-based necessary spatial resolution and contrast to capture the smallest vessels from casts. Tumors with damaged vessel walls are inappropriate for casting. Therefore, phase tomography was applied to visualize the capillaries. Grating-based tomography yields the necessary contrast but vessels with a diameter smaller than 20 provides the necessary spatial resolution but hardly enough contrast. Consequently, we propose first to improve the spatial resolution of grating-based tomography, second to identify rather simple in-line tomography approaches such as the one introduced by Paganin searching for better contrast, and third to combine tomograms from both approaches to gain additional information toward the smallest capillaries.