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**Overview**: FISH t(15;17) PML RARA Panel**Introduction**: The FISH t(15;17) PML RARA Panel is a diagnostic tool designed to detect t(15;17) in leukemia using whole blood or bone marrow samples. In India, t(15;17)(q24;q21) PML/RARA fusion is pathognomonic for acute promyelocytic leukemia (APL), accounting for ~10-15 percent of AML cases, with excellent prognosis (>90 percent cure rate) when treated promptly with ATRA + arsenic trioxide. High morbidity from under-testing in rural/low-SES patients with coagulopathy, delayed ATRA leading to fatal hemorrhage or differentiation syndrome. Per hematology practices aligned with ICMR and Indian Society of Hematology guidelines, the test employs FISH for PML/RARA translocation over 1-2 days with high sensitivity/specificity, valuable for rapid APL diagnosis and immediate therapy initiation. This diagnostic falls under genetic cancer screening and targets patients with suspected APL (DIC, promyelocytes), addressing accurate detection to guide ATRA/ATO and prevent early mortality. With elevated morbidity due to under-testing, the test supports public health efforts by enabling precise molecular confirmation and dramatically improving APL survival. Its blood/bone marrow-based approach ensures reliable fusion detection.**Other Names**: FISH t(15;17) Pnl.**FDA Status**: FDA approved, CLIA certified for cytogenetics/oncology, compliant with 2025 standards.**Historical Milestone**: PML/RARA FISH diagnostic; in India, used in APL protocols.**Purpose**: The test detects 2 parameters including PML/RARA translocation to guide APL genetic assessment, confirm diagnosis, inform ATRA/ATO therapy.**Test Parameters**: 1. PML/RARA Translocation, 2. Chromosomal Rearrangement.**Pretest Condition**: No fasting required; patients should have suspected APL or coagulopathy.**Specimen**: 3 mL whole blood or bone marrow in 1 EDTA tube, transported within specified times to maintain sample viability.**Sample Stability at Room Temperature**: 48 hours with proper handling to preserve cell viability, ensuring reliable test performance.**Sample Stability at Refrigeration**: 7 days at 2-8 degrees Celsius, suitable for short-term storage before laboratory processing, though immediate testing is preferred.**Sample Stability at Frozen**: Not applicable (fresh sample preferred for FISH).**Medical History**: Patients should provide details on bleeding, DIC, promyelocyte count.**Consent**: Written informed consent is required, detailing the test's purpose, potential risks of undetected APL including hemorrhage, benefits of rapid detection, and minimal discomfort from blood/bone marrow draw.**Procedural Considerations**: The test involves sample processing using FISH by trained personnel to ensure sterile technique, avoid contamination, and interpret results within 1-2 days using provided probes/controls. Laboratories must maintain a controlled environment, adhere to quality assurance protocols.**Factors Affecting Result Accuracy**: Delays beyond stability periods, improper storage conditions, or low blast count can affect results. Correlation with clinical evaluation or additional testing is recommended to confirm findings.**Clinical Significance**: Positive PML/RARA confirms APL, necessitating immediate ATRA/ATO. Negative may require follow-up.**Specialist Consultation**: Hematologists/oncologists should be consulted for management.**Additional Supporting Tests**: PML/RARA PCR, karyotype for confirmation.**Test Limitations**: Detects translocation only; comprehensive approach required.**References**: Indian Journal of Hematology 2024, APL Studies India 2023. |
