Response to multimodal treatment in advanced neuroblastomas. Factors associated with complete remission induction, and factors associated with prolonged survival.

The influence of patient and treatment variables upon the probabilities of response to chemotherapy in advanced neuroblastomas was investigated in 71 children with stages III-IV disease treated in Denmark between 1965-1980. The therapeutic regimens consisted of various combinations of chemotherapeutic agents with or without surgical excision of the primary tumour and irradiation. Complete response (CR) was achieved by 75% of patients in stage III, and another 17% showed partial response. In stage IV 60% responded, 19% with CR. Relationships between patient and treatment variables and the probability of being alive in CR 22 weeks after initiation of the treatment were examined by logistic regression analysis. The probability of CR was not related to age at diagnosis, the addition of an anthracycline to the chemotherapeutic regimens, or to irradiation. Factors related to the maintenance of CR could not be statistically examined due to the small number of complete responders at 22 weeks. Only age below 2 years seems, however, to have positive impact on the response duration. The influence of patient characteristics was further suggested by the result of secondary treatment attempts. 42% of the patients selected for secondary treatment responded, and 17% achieved CR. 1/25 (4%) had survived disease-free for more than 8 years. Factors related to the duration of survival were subsequently examined in the 71 children using Cox's regression analysis. Only children below 2 years of age at diagnosis had survived for more than 8 years. Resection of the tumour at diagnosis, irradiation and the addition of an anthracycline appear not to influence the length of survival in this patient population.