Prolonged Survival of a 79-Year Old Man with Acute Myeloid Leukemia M2, Normal Karyotype, NPM1 and FLT3-ITD Mutations, WBC 33.7 × 109/L, and Involving only Granulocyte-Macrophage Line on 53 Cycles of Low-Dose Cytarabine

Case Presentation

Ann Hematol Oncol. 2019; 6(11): 1276.

Prolonged Survival of a 79-Year Old Man with Acute Myeloid Leukemia M2, Normal Karyotype, NPM1 and FLT3-ITD Mutations, WBC 33.7 × 109/L, and Involving only Granulocyte-Macrophage Line on 53 Cycles of Low-Dose Cytarabine

Lemež P1*, Dignum H1, Ganczakowski M1, Chiecchio L2, Ayto R1, Baker K2, Singh S1, Cranfield T1, Matthias G1, James C1 and Corser R1

¹Department of Haematology, Queen Alexandra Hospital, Portsmouth, United Kingdom

²Wessex Regional Genetics Laboratory, Salisbury NHS Foundation Trust, Salisbury District Hospital, United Kingdom

*Corresponding author: Lemež P, Department of Haematology, Queen Alexandra Hospital, Southwick Hill Road, Cosham, Portsmouth, Hampshire PO6 3LY, United Kingdom

Received: August 30, 2019; Accepted: November 29, 2019; Published: December 06, 2019

Abstract

The prognosis of older patients with de novo Acute Myeloid Leukemia (AML) is usually dismal. Palliative therapy with LDAC is one of the treatment options with a median survival of less than one year. Several reported older cases with AML with a survival of 25-51 months on therapy with LDAC lack details of the AML type, clinical characteristics, and treatment. This case report describes a 79-year old man with AML M2, normal karyotype, leukocytosis 33.7 x 109/L, and involving only Granulocyte-Macrophage Line (GM-AML) who survived 84 months on 53 repeated cycles of LDAC, the longest described survival on LDAC. His leukemic cells exhibited Nucleophosmin 1 (NPM1) mutation and Fms-Like Tyrosine-kinase 3 gene (FLT3) Internal Tandem Duplication (ITD) with a high FLT3-ITD to FLT3 WT allelic ratio, typical immunophenotype, morphology and no dysplastic features. We propose that older patients with de novo GM-AML with these characteristics may benefit from prolonged LDAC therapy.

Keywords: Acute myeloid leukemia; Cytarabine; Hematopoietic myelodysplasia; NPM1; FLT3

Abbreviations

AML: Acute Myeloid Leukemia; AML-MRC: AML with Myelodysplasia-Related Changes; EMD: Erythroblastic and/or Megakaryocytic Dysplasia; BM: Bone Marrow; FBC: Full Blood Cell count; FLT3-ITD: Fms-like Tyrosine kinase-3 gene (FLT3) Internal Tandem Duplication (ITD); FLT3 WT: FLT3 Wild Type; GM-AML: AML involving only cells of Granulocytic-Macrophage line; CR: Complete Remission; HC: Hydroxycarbamide; LDAC: Low-Dose Cytarabine; NK: normal karyotype; NPM1: Nucleophosmin 1 gene; PML/RARA: Fusion gene of Promyelocytic Leukemia gene/Retinoic Acid Receptor-Alpha gene; PS: Performance Status; RBC: Red Blood Cells; SICT: Standard-Dose Induction Chemotherapy; WBC: White Blood Cells

Introduction

The prognosis of older patients with de novo Acute Myeloid Leukemia (AML) is poor. Palliative therapy using Low-Dose Cytarabine (LDAC) is one of the standard treatment options [1]. B.D. Cheson et al. (1986) reviewed studies on LDAC treatment in 237 patients with de novo AML of whom 77 (34%) achieved Complete Remission (CR) with a median duration of 9.5 months, the longest CR duration was 28 months and survival 30 months [2]. The UK MRC AML 14 Trial reported 102 elderly patients with AML treated with LDAC cycles who achieved CR in 18% with one exceptionally long CR duration of 51 months [3]. No diagnostic or clinical data of cases with their longest survival were described in these studies [2,3].

Here we report a case of de novo AML M2 [4] who had the first reported survival of greater than 5 years on repeated LDAC cycles. A detailed description of his AML characteristics and his therapy with LDAC cycles timing is presented which may be useful for selection of this successful and well-tolerated treatment in similar cases.

Case Presentation

A 79-year old gentleman with a three weeks history of tiredness, weakness, night sweats and a recent episode of spontaneous epistaxis was admitted to Queen Alexandra Hospital (QAH) on December 5, 2011. His past medical history included right leg deep venous thrombosis with pulmonary embolism (1982), hypertension (1989), bilateral total knee replacement (2001/2). A routine blood count seven weeks prior had been normal (Table 1).

Citation: Lemež P, Dignum H, Ganczakowski M, Chiecchio L, Ayto R, Baker K, et al. Prolonged Survival of a 79- Year Old Man with Acute Myeloid Leukemia M2, Normal Karyotype, NPM1 and FLT3-ITD Mutations, WBC 33.7 × 109/L, and Involving only Granulocyte-Macrophage Line on 53 Cycles of Low-Dose Cytarabine. Ann Hematol Oncol. 2019; 6(11): 1276.