Introduction: Mixed-phenotype acute leukemia (MPAL) is a rare, biologically highrisk acute leukemia characterized by blasts expressing markers of more than one hematopoietic lineage. It accounts for <4% of acute leukemias. MPAL with B- and T-lineage differentiation (MPAL-B/T) is exceptionally rare, comprising ~6% of MPAL cases, with limited pediatric reports. Accurate recognition is critical, as this entity carries distinct therapeutic and prognostic implications compared with lineage-defined leukemias. Case Presentation: We report a 12-year-old Filipino female presenting with epistaxis, pallor, and easy bruising. Laboratory studies revealed severe anemia, hyperleukocytosis, and circulating blasts. Peripheral blood flow cytometry revealed 73% blasts co-expressing T-lineage markers (surface and cytoplasmic CD3, CD5, CD7) and B-lineage markers (CD19, cytoplasmic CD79a), with CD34 and HLA-DR. Bone marrow flow cytometry confirmed persistent dual-lineage expression in blasts comprising 21% of total events. Discussion: The findings meet WHO diagnostic criteria for MPAL, with definitive T-lineage assignment via cCD3 and strong B-lineage expression with CD19 and cCD79a. By European Group for the Immunological Classification of Leukemias criteria, lineage scores were 3.5 (T) and 3 (B), consistent with biphenotypic leukemia. MPAL has inferior survival compared with lineage-defined ALL and remains therapeutically challenging due to uncertainty in optimal induction strategy. Emerging data support ALL-directed regimens with risk-adapted consolidation, underscoring that precise immunophenotypic classification informs treatment algorithms and risk stratification. Misclassification as isolated T-ALL or B-ALL may lead to inappropriate therapy and poorer outcomes. Conclusion To our knowledge, this is the first reported Filipino pediatric MPALB/T case, emphasizing the need for comprehensive immunophenotyping and local molecular and outcome data to guide evidence-based management.
Leukemia, Biphenotypic, Acute ; Phenotype ; T-Lymphocytes

RUNX1::RUNX1T1 is a core-binding factor driving fusion gene which arises from t(8;21)(q22;q22). It is one of the most common chromosomal rearrangements in both pediatric and adult Acute Myeloid Leukemia (AML) with a reported incidence o 15% in children and young adults. There are few case reports documenting RUNX1::RUNX1T1 translocation in pediatric AML. Although this is generally associated with a favorable prognosis, we report two (2) cases of de novo pediatric AML in the Philippines harboring a RUNX1::RUNX1T1 translocation, one eventually relapsed while the other attained remission but succumbed to sepsis.
Next Generation Sequencing ; RUNX1::RUNX1T1 fusion

Secretory carcinoma is a recently described salivary gland neoplasm reported in the fourth edition of World Health Organization classification of head and neck tumors.1 We report a case of a primary secretory carcinoma arising from the submandibular gland that was completely excised in a 10-year-old. The histomorphologic features and the immunophenotype studies are compatible with secretory carcinoma. Unless proven otherwise by immunohistochemical stains and cytogenetics, secretory carcinoma should be included as a differential in cases of lesion of the major and minor salivary glands that has the primary differential diagnosis of acinic cell carcinoma. This case report aims to contribute to the limited literature about this disease entity and would be one of the few reported cases of the disease in a school-age child.