Survival forests under test: Impact of the proportional hazards assumption on prognostic and predictive forests for amyotrophic lateral sclerosis survival.

We investigate the effect of the proportional hazards assumption on prognostic and predictive models of the survival time of patients suffering from amyotrophic lateral sclerosis. We theoretically compare the underlying model formulations of several variants of survival forests and implementations thereof, including random forests for survival, conditional inference forests, Ranger, and survival forests with splitting, with two novel variants, namely distributional and transformation survival forests. Theoretical considerations explain the low power of log-rank-based splitting in detecting patterns in non-proportional hazards situations in survival trees and corresponding forests.

Reduced vs. standard dose native E. coli-asparaginase therapy in childhood acute lymphoblastic leukemia: long-term results of the randomized trial Moscow-Berlin 2002.

Purpose: Favorable outcomes were achieved for children with acute lymphoblastic leukemia (ALL) with the first Russian multicenter trial Moscow-Berlin (ALL-MB) 91. One major component of this regimen included a total of 18 doses of weekly intramuscular (IM) native Escherichia coli-derived asparaginase (E. coli-ASP) at 10000 U/m during three consolidation courses.

[Age-related characteristics of the efficacy of different glucocorticosteroids in the therapy of acute lymphoblastic leukemia].

Aim: To determine predictors for decision-making on a differential approach to choosing glucocorticosteroids (GCS) for children and adolescents with acute lymphoblastic leukemia (ALL).

Subjects And Methods: The analysis covered 1064 primary patients aged to 1 to 18 years with ALL who had been registered at the clinics of Russia and Belorussia in April 2002 to November 2006. Before induction therapy, the patients were randomized into a dexamethasone (DEXA) 6 mg/m2 group (n=539) and a methylprednisolone (MePRED) 60 mg/m2 one (n=525).

[Non-calculous cholecystitis as a surgical problem].

Experience with the surgical treatment of 263 patients with acalculous cholecystitis is presented. Planned and postponed operations were fulfilled on 188 patients. 75 operations were performed for urgent indications.