Outcomes of Children treated for Relapsed or Refractory Acute
Lymphoblastic Leukaemia: A Single Tertiary Care Centre Experience
Abstract
Background: Acute Lymphoblastic Leukaemia (ALL) , most common malignancy
amongst children with front-line treatment considered major success,
20% of children predicted to either relapse or show resistance to
treatment with reported dismal outcomes. Aim: To evaluate clinical
characteristics of children diagnosed with refractory / relapsed ALL and
to determine 3-year overall survival ouctomes. Method: Retrospective
review of patients (aged 1 -14 years) diagnosed with ALL during the
period January 2002 to December 2018, data extracted for details of
baseline characteristics at diagnosis and at relapse . Results: Total of
347 newly diagnosed children with ALL identified, three induction
failures and 28 relapses, with total 31 patients a cohort relapse rate
of 9% observed. The male-to-female ratio observed is 4.16:1 and mean
duration of CR1 was 26 months : 15 (48%) relapsing ≤ 18 months,seven
(23%) during 18 to 36 months and nine (29%) relapsed > 36
months of IF or CR1.Eighteen patients (62%) had isolated BM relapse,
six (20%) patients experience isolated Extra-medullary relapse and five
(17%) patients experienced BM with other sites. Three-year Overall
Survival (OS) of the cohort was 62.3%, while of those patients who
achieved CR post first-salvage therapy 3-year OS of 79.5% observed with
a statistically significant difference, p value <0.05
comparing to patients who did not achieve remission post first-salvage
therapy (3-year OS: 46.4%). The same statistical difference observed in
3-years OS observed comparing duration of remission of CR prior to
relapse: ≤ 18 months: 33.2%; 18 – 36 months: 66.7% and >
36 months: 87.5%; the same trend continued when comparing 3-years OS
based on risk stratification at relapse: LR: 83.3%; IR: 80% and HR:
44.8%. Conclusion: Incidence and outcomes reported on this study is
comparable to internationally reported data with duration of CR1,
risk-stratification at relapse and remission status post-salvage therapy
determined as significant prognostic factors for survival. No survivial
difference amongst patients who received HSCT after induction to those
who received chemotherapy, could be attributed to a smaller sample size
warranting a multi-institutional observational study. The findings
corroborates with the need for novel therapies and treatment approaches
in these group of patients