PCR- Negative Atypical PML-RARA Rearrangement in Pediatric Acute Promyelocytic Leukemia

• Dan-Ping Huang

  Department of Pediatrics, the First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China

• Yi-Jun Chen

  Department of Pediatrics, the First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China

• Jie-Si Luo

  Department of Pediatrics, the First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China

• Shao-Qian Chen

  Department of Clinical Laboratory, the First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China

• Jing Cheng

  Department of Clinical Laboratory, the First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China

• Yu Li

  Department of Pediatrics, the First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China

• Cong Liang

  Department of Pediatrics, the First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China

• Li-Na Wang

  Department of Pediatrics, the First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China

• Zhong Fan

  Department of Pediatrics, the First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China

• Xiao-Li Zhang

  Department of Pediatrics, the First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China

• Xue-Qun Luo

  Department of Pediatrics, the First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China

• Li-Bin Huang

  Department of Pediatrics, the First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China

• Yan-Lai Tang

  Department of Pediatrics, the First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China

Acute promyelocytic leukemia (APL) is a special type of acute myeloid leukemia (AML), accounting for about 5% to 10% of children with AML. At the genetic level, APL is featured by a unique chromosome translocation t(15;17) which results in the PML-RARA gene fusion. Most patients can be diagnosed by traditional karyotype analysis, Fluorescence-In-Situ Hybridization (FISH), or Reverse Transcription-Polymerase Chain Reaction (RT-PCR). We report the case of a child with acute promyelocytic leukemia (APL) who had characteristic chromosome translocation t(15;17) and rare PML-RARA gene mutation. This patient had an excellent response to chemotherapy, suggesting that this mutation will not affect the treatment and prognosis of APL.

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