Histological comparison of primary and xenograft tumours.

<p>Shown here are H&E stains of primary and xenograft tumours. A. Primary and xenograft tumours show similar differentiation phenotypes ranging from overall poor differentiation (−) over micropapillary growth (x) to more differentiated ductular formations (*). B. Perineuronal invasion can be observed in both primary and xenograft tumours (arrow heads). C. Shown here are areas of tumour necrosis, demarcated by neutrophil granulocytes (C i, asterisks) and tumour infiltration of lymphatic vessel (C ii, arrow head). D. Distribution of stroma (S) in primary and xenograft tumour tissue. Tumour cells of both specimens are embedded in desmoplastic tumour stroma. While stroma in the primary tumour is dispersed throughout the tumour, it is more localized in the xenograft.