OBJECTIVE: Acute lymphoblastic leukemia (ALL) may present with signs and symptoms related to extramedullary involvement, therefore, leads to delayed diagnosis of ALL in children. This study aims to consider the extramedullary manifestations of ALL in children and their proper treatment.
METHODS: The databases were searched for all relevant subjects including \"acute lymphoblastic leukemia\", \"clinical presentation\", \"unusual presentation\", \"childhood acute lymphoblastic leukemia\", \"presenting features of ALL\", \"extramedullary presentation\", and \"atypical presentation\" from April 1968 to June 2020. The Inclusion criteria for this review study were all cases reported, case series, and studies about extramedullary presentations of ALL in pediatrics. Eighty-seven studies had inclusion criteria. All reported studies were analyzed given their extramedullary presentations, age, sex, treatment option, and prognostic factors. A two-sided P-value less than 0.05 was considered statistically significant.
RESULTS: In this review study, the extramedullary initial signs and symptoms of ALL were related to musculoskeletal system 17 (19.5%) especially bony symptoms and hypercalcemia. The additional extramedullary presentations of ALL in order of frequency include; renal involvement, 17 (19.5%), hepatic symptom 12 (13.8%), orbital presentation 10 (11.5%), neurologic signs 8 (9%), dermatological manifestations 5 (5.8%), oral presentations 5 (5.8%), hypereosinophilia 5 (5.8%), abdominal manifestation 3 (3.5%), pericardial involvement 2 (2.3%), and the other miscellaneous presentations 3 (3.5%).
CONCLUSIONS: The clinicians must become familiar with these extramedullary presentations of ALL in pediatrics to avoid the delayed diagnosis of this disease and increase the probable chance of survival by early detection.