Cytogenetically Cryptic Acute Promyelocytic Leukemia: A Diagnostic Challenge

Cytogenetically cryptic acute promyelocytic leukemia (APL) is rare, characterized by typical clinical and morphological features, but lacks t(15;17)(q24;q21)/PML::RARA translocation seen in conventional karyotyping or FISH. The prompt diagnosis and treatment of APL are critical due to life-threatening complications associated with this disease. However, cryptic APL cases remain a diagnostic challenge that could mislead the appropriate treatment. We describe four cryptic APL cases and review reported cases in the literature. Reverse transcriptase polymerase chain reaction (RT-PCR) is the most efficient diagnostic modality to detect these cases, and alternative methods are also discussed. This study highlights the importance of using parallel testing methods to diagnose cryptic APL cases accurately and effectively.

Automated summary

Cytogenetically cryptic acute promyelocytic leukemia (APL) is a rare disease characterized by typical clinical and morphological features, but lacks detectable genetic translocation. Prompt diagnosis and treatment are crucial due to potential life-threatening complications. This study presents four cases of cryptic APL and reviews previous reports, highlighting the importance of parallel testing methods, especially reverse transcriptase polymerase chain reaction (RT-PCR), for accurate and effective diagnosis.