Science in the court.

The nude mouse has several advantages for the study of human tumours. Compared to adult cancers (Sharkey et al., 1978), paediatric tumours have been less extensively xenografted into nude mice (Helson, 1982). The only large series was published by Neely et al. (1983). Most infantile solid tumours are considered embryonic because of the age at which they occur and their potential for differentiation (Willis, 1962). In addition to our interest in perpetuating tumour material to study particular malignant processes (Rousseau-Merk et al., 1982a, b), we grafted 60 embryonic tumours in order to correlate transplantability with histological group type, clinical data and relapse-free periods in the patient. Data on 13 other malignant paediatric tumours, and 12 benign tumours are also reported. Tumour material was obtained by surgical excision. Histological types are described in Table I and comprise 60 embryonic tumours, 13 other childhood tumours and 12 benign ones. Forty-eight of the tumours were treated by radiotherapy and/or chemotherapy. Nephroblastomas received either radiotherapy (20 Gy) or chemotherapy including the combination actinomycin D plus vincristine. Chemotherapy was given one month prior to excision of the primary tumours. In cases of relapse periods treatment varied according to the time of onset. Primary rhabdo-myosarcomas were treated at various times prior to excision by chemotherapy (vincristine + actinomycin D + cyclophosphamide). Cases of relapse received the same chemotherapy with the addition of adriamycin and, in some cases, radiotherapy (45 Gy).