The prophylactic use of granulocyte-colony stimulating factor during remission induction is associated with increased leukaemia-free survival of adults with acute lymphoblastic leukaemia: a joint analysis of five randomised trials on behalf of the EWALL.

BACKGROUND

Granulocyte-colony stimulating factor (G-CSF) is used to prevent febrile neutropenia and support intense chemotherapy. However, its impact on long-term outcome in oncological patients including adults with acute lymphoblastic leukaemia (ALL) has not been determined so far.

METHODS

In the current study follow-up data from individual patients recruited in five multicentre, prospective, randomised trials were pooled to perform a joint analysis. Among 347 adults and adolescents with ALL, 185 were assigned to receive prophylactically G-CSF along with induction chemotherapy while 162 patients were treated without G-CSF support.

RESULTS

With the median follow-up of 5.3years, there was a tendency towards increased 5year probability of the overall survival for the G-CSF arm compared to the controls (32%±4% versus 23%±4%, p=.07), which reached statistical significance in a subgroup of T-ALL (51%±8% versus 29%±9%, p=.01) and among patients aged 21-40years (44%±6% versus 27%±6%, p=.03). The probability of leukaemia-free survival was 38%±4% and 24%±4% (p=.01) while the median remission duration equalled 33 and 17months (p=.007), respectively. In a multivariate analysis the prophylactic use of G-CSF was independently associated with reduced risk of relapse (hazard ratio (HR)=.64, p=.007) and treatment failure (HR=.67, p=.02).

CONCLUSIONS

The prophylactic use of G-CSF during induction of ALL is associated with improved long-term outcome and should be recommended especially in a setting of T-ALL and in 'young adults'. Our analysis provides the first direct evidence coming from prospective trials for the impact of primary G-CSF prophylaxis on disease-free survival of oncological patients.