Atypical features in a patient with acute promyelocytic leukaemia: a potential diagnostic pitfall

Abstract

Acute promyelocytic leukaemia (APML) is a malignancy with a high cure rate; however, delay in diagnosis or treatment can result in morbidity and mortality. APML has characteristic clinical, morphological, immunophenotypic and molecular features. In patients with acute leukaemia, a high index of suspicion is required to exclude APML. Very rarely APML patients at diagnosis can demonstrate atypical features. We reported a patient whose bone marrow features resembled acute myeloid leukaemia with predominantly agranular blasts, devoid of Auer rods and expressing CD34 and HLA-DR on flow cytometry. APML was not suspected initially but after cytogenetic and molecular genetic studies demonstrated t(15;17), appropriate therapy with ATRA+ chemotherapy was instituted and the patient showed remarkable and sustained response to treatment. This case highlights the fact that morphology and immunophenotyping are useful but not infallible indicators for these malignancies and, ultimate diagnoses will require detection of the characteristic molecular markers.

Hyperbasophilic Variant of Acute Promyelocytic Leukemia

“…The life threatening bleeding complications, including intracranial hemorrhage, are common during the first two weeks of induction therapy requiring close monitoring and management with products such as fresh frozen plasma and cryoprecipitates 5 .…”

PML(NLS¯) protein: A novel marker for the early diagnosis of acute promyelocytic leukemia

“…Acute promyelocytic leukemia (APL) is a type of acute myeloid leukemia (AML) with a high cure rate. However, delays in the diagnosis and treatment of APL are associated with increased morbidity and mortality ( 1 ). Bone marrow smearing for pathological examination is considered to be the gold standard in the diagnosis of APL; however, it is time-consuming and usually painful for the patients.…”