SOLVING DIAGNOSTIC CHALLENGES IN PEDIATRIC SMALL ROUND CELL TUMORS WITH IMMUNOHISTOCHEMISTRY
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Keywords
Pediatric Small Round Cell Tumors; Immunohistochemistry; Diagnostic Accuracy; Ewing Sarcoma; Rhabdomyosarcoma; Pathology
Abstract
BACKGROUND: Pediatric small round cell tumors (SRCTs) are a group of aggressive cancers that look very similar under the microscope, making them difficult to tell apart based on appearance alone. An accurate diagnosis is critical because each type requires different treatment.
AIM: This study aimed to test how effective a standard panel of immunohistochemistry (IHC) stains is at providing a definitive diagnosis for these challenging tumors.
METHODS: We conducted a prospective study of 100 children with SRCTs. After an initial review under the microscope, all cases were tested with a targeted IHC panel designed to identify different tumor lineages (including CD99, myogenin, CD45, and synaptophysin).
RESULTS: Initial microscopic examination failed to provide a specific diagnosis in 71% of cases, labelling them only as "undifferentiated." The IHC panel successfully resolved 99% of all cases, providing a specific diagnosis. The Ewing sarcoma family (50%) was the most common tumor, followed by embryonal rhabdomyosarcoma (17%).
CONCLUSION: A systematic IHC panel is a highly effective and essential tool for diagnosing pediatric SRCTs. It resolves the vast majority of ambiguous cases, ensuring that children receive the correct diagnosis as the crucial first step towards appropriate therapy.
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Dr. Divya Jain
Assistant Professor, Department of Pathology, Government Medical College, Alwar
Dr. Achin Gupta
Assistant Professor, Department of Anaesthesia, Govt Medical College, Alwar
Dr. Neeraj Raman
Assistant Professor, Department of Microbiology, Govt Medical College, Alwar
Dr. Amandeep
Assistant Professor, Department of Pediatrics, Government Medical College, Alwar