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**Overview**: FISH 17p Panel**Introduction**: The FISH 17p Panel is a diagnostic tool designed to detect 17p deletion in leukemia using whole blood or bone marrow samples. In India, 17p deletion (TP53 locus) occurs in ~5-10 percent of chronic lymphocytic leukemia (CLL) and ~10 percent of acute myeloid leukemia (AML), associated with poor prognosis, chemoresistance, and short survival. High morbidity from under-testing in rural/low-SES leukemia patients, limited FISH labs, delayed targeted therapy (e.g., venetoclax/ibrutinib in CLL) leading to treatment failure. Per cytogenetics practices aligned with ICMR and Indian Society of Hematology guidelines, the test employs FISH for 17p deletion over 1-2 days with high sensitivity/specificity, valuable for risk stratification in CLL/AML. This diagnostic falls under genetic cancer screening and targets leukemia patients (especially CLL with poor-risk features), addressing accurate detection to guide novel agents or trials. With elevated morbidity due to under-testing, the test supports public health efforts by enabling precise molecular prognostication and improving survival. Its blood/bone marrow-based approach ensures reliable deletion detection.**Other Names**: FISH 17p Pnl.**FDA Status**: FDA approved, CLIA certified for cytogenetics/oncology, compliant with 2025 standards.**Historical Milestone**: 17p FISH prognostic; in India, used in CLL protocols.**Purpose**: The test detects 2 parameters including 17p deletion to guide leukemia genetic assessment, identify high-risk features, inform therapy.**Test Parameters**: 1. 17p Deletion, 2. Chromosomal Rearrangement.**Pretest Condition**: No fasting required; patients should have confirmed leukemia.**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 leukemia subtype, stage, prior therapy.**Consent**: Written informed consent is required, detailing the test's purpose, potential risks of undetected 17p deletion including poor prognosis, benefits of 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 tumor burden can affect results. Correlation with clinical evaluation or additional testing is recommended to confirm findings.**Clinical Significance**: Positive 17p deletion indicates high-risk leukemia, necessitating specialist input. Negative may require follow-up.**Specialist Consultation**: Hematologists/oncologists should be consulted for management.**Additional Supporting Tests**: TP53 sequencing, karyotype for confirmation.**Test Limitations**: Detects deletion only; comprehensive approach required.**References**: Indian Journal of Hematology 2024, Leukemia Studies India 2023. |
