Study design
This was a retrospective medical records study of children (0-16 years)
diagnosed with ALL at MTRH from January 2017 to December 2020. We
included all children with a diagnosis of ALL, regardless of their
clinical condition, before the initiation of treatment. Previous medical
record data before (2010-2016) modification of induction therapy, with
improved social and financial support and supportive care, was available
for comparison.
Socio-demographic data, including age, gender, the distance of residence
from MTRH, and duration of symptoms, had been collected at diagnosis for
the current cohort (2017-2020) and was available. In addition, we
obtained data on health insurance status and treatment outcomes from the
medical records. We recorded treatment outcomes as abandonment, death,
relapsed or progressive disease, and event-free. Additional clinical
data for the current cohort (2017-2020) included:
white blood cell (WBC) count at
diagnosis, ALL immunophenotype, and central nervous system (CNS) disease
status. We determined survival through induction and the survival
estimates by WBC, sex, age at diagnosis, health insurance status (NHIF)
at diagnosis, event-free and overall survival.
The children with ALL at MTRH were treated with a modification of the
Dutch Oncology Group ALL-6 Study (1984-1988) therapy for non-high-risk
ALL.14 All patients received the same standard
protocol without risk stratification and consisted of induction (6
weeks), consolidation (2 weeks), methotrexate phase (7 weeks),
re-induction (3 weeks), and maintenance therapy (83 weeks). For this
cohort study (2017-2020), doxorubicin was dropped from the induction
phase) as the supply of vincristine, prednisone, and especially
L-asparaginase was improved. The additional modification included
intensified L-asparaginase therapy and a fourth high-dose methotrexate.
The duration of ALL treatment lasts for 104 weeks (supplementary
material, TABLE S1).
The diagnosis of ALL was made based on a bone marrow examination by the
pathologists. Due to financial constraints, the use of flow cytometry to
further confirm the diagnosis and determine ALL immunophenotypes could
only be done in some patients.
Refusal to start or continue with planned treatment for four or more
weeks consecutively was considered treatment
abandonment.9,15 Induction or early deaths were those
that occurred before the start of treatment or during induction
(<42 days from the start of treatment).3,9Deaths that occurred before the start of treatment or following
relapsed/progressive leukemia were deemed to be disease-related. The
deaths that occurred after treatment was initiated were deemed to be
treatment-related. The clinical signs and symptoms and the presence of
lymphoblasts on bone marrow aspirate or peripheral blood smear confirmed
the relapsed disease). CNS involvement was evaluated through
cerebral-spinal fluid examination, which was reported as positive or
negative.
This study was approved by the Institutional research and ethics
committee of MTRH and Moi University.