Pleomorphic (anaplastic) neuroblastoma in nude mice.
 Two pleomorphic (anaplastic) neuroblastomas, from two children aged 1 and 6 years, were transplanted into nude mice.
 Two noteworthy observations were made.
 In one case, the transplanted tumor gave rise to a soft-tissue sarcoma.
 Moreover, in both cases hepatic metastases were associated with a striking modification of murine hepatocytes, resulting in hyperchromatic and dysplastic nuclei.
 The latter finding was particularly evident in the hepatic areas surrounding all metastases of pleomorphic (anaplastic) neuroblastoma cells.
