# Acute lymphoblastic leukemia with bone marrow necrosis as the first clinical manifestation: a pediatric case report

## TL;DR

A 4-year-old child with acute lymphoblastic leukemia was initially diagnosed with bone marrow necrosis, highlighting the need for thorough diagnostic approaches in rare cases.

## Contribution

This case report highlights the rare presentation of ALL with bone marrow necrosis and emphasizes the importance of multi-site bone marrow evaluation.

## Key findings

- Bone marrow necrosis was the initial clinical manifestation of ALL in a 4-year-old child.
- Multi-site bone marrow aspiration and biopsy were essential for confirming the diagnosis of common B-cell ALL.
- The child responded well to treatment, achieving complete remission with MRD monitoring.

## Abstract

This paper reports a rare case of a 4-year-old male child with acute lymphoblastic leukemia (ALL) presenting initially with bone marrow necrosis (BMN) as the chief clinical manifestation. The child sought medical attention due to fever, bone pain, and fatigue. Laboratory tests indicated pancytopenia. Initial bone marrow cytomorphology examination revealed disrupted cellular architecture, suggesting possible BMN, and single-site flow cytometry detected no definitive abnormalities, highlighting the diagnostic complexity caused by BMN. Through multi-site bone marrow aspiration and biopsy, the diagnosis was ultimately confirmed as common B-cell ALL (common-B-ALL). Treatment followed the South China Children’s Cancer Collaborative Group SCCCG-ALL-2023 protocol, incorporating blinatumomab immunotherapy based on risk stratification. The child responded well to treatment and is currently in the maintenance chemotherapy phase, with minimal residual disease (MRD) monitoring consistently indicating complete remission. This case emphasizes the importance of early recognition of rare presentations like BMN-onset in pediatric ALL, the necessity of multi-site bone marrow examination, and the crucial role of individualized treatment strategies.