ABSTRACT
In a mouse without an immune system, it was tempting to develop the tumor in a place that could easily allow inspection of tumor take and growth. On histological examination, the tumor appeared to be similar to the patient's tumor. Since the first human malignant tumor was implanted subcutaneously (s.c.) in nude mice in 1969,' this site for implantation seems to be the most popular, as based on a survey of the literature. The presence of mouse stroma was first described in isoenzyme studies of transplanted Burkitt's lymphoma. Konerding et al. have carried out elegant studies on the vascular system of implanted human melanomas and sarcomas into nude mice. They used microcorrosion casting and found that the vascular system of xenografts can be described in terms of a simply structured system, lacking not only a hierarchy with respect to wall formation, but also to vascular distribution.
