Leukemia is observed with increased frequency in patients with severe congenital neutropenia (SCN). In the past decade, recombinant human granulocyte colony-stimulating factor (rh G-CSF) has prolonged the survival of patients with SCN increasingly reported to have leukemias. In this communication acute myelogenous leukemia (AML) associated with a mutation of the G-CSF receptor (G-CSF-R) developed in a patient with SCN maintained on long-term G-CSF therapy. The blast count in the blood and bone marrow fell to undetectable levels twice on withholding G-CSF and without chemotherapy administration, but the mutant G-CSF-R was detectable during this period. The patient subsequently underwent successful allogeneic bone marrow transplantation. After transplantation, the patient's neutrophil elastase (ELA-2) mutation and G-CSF-R mutation became undetectable by polymerase chain reaction. This report provides novel insights on leukemia developing in congenital neutropenia.

Severe congenital neutropenia (SCN), first described by Kostmann in 1956, is a disorder of myelopoiesis characterized by impaired neutrophil differentiation with maturation arrest at the promyelocyte stage.1,2 The resultant profound neutropenia usually leads to fatal infections early in infancy, but in a few instances it has remitted or has been mild enough to allow prolonged survival. Transition to leukemia has been reported in 3 patients who survived through adolescence with no cytokine treatment.3-5 Bone marrow transplantation was the only effective therapy to prolong the survival of patients with SCN6,7 until granulocyte–colony-stimulating factor (G-CSF) was introduced.8-10 However, an apparent increase in the incidence of leukemia has also been observed in the past few years.11,12 This phenomenon could be related to prolonged survival of children who have a preleukemic disorder, thus allowing the disease to follow its natural course. Prolonged hematopoietic stimulation with G-CSF has also been suggested to contribute to the development of leukemia.13-15 We present a patient with SCN in whom acute myelogenous leukemia (AML) developed after 9 years of G-CSF treatment. The leukemia remitted spontaneously with the discontinuation of G-CSF alone, allowing the patient to receive a successful unrelated bone marrow transplant without the morbidity of induction chemotherapy.

M.P. is a 12-year-old boy who received a diagnosis of severe neutropenia at the age of 3 months. There is no family history of consanguinity or hematologic disorders. During the first 3 years of his life, he was admitted to the hospital more then 30 times for life-threatening infections. At age 3, G-CSF treatment was begun, and the patient was maintained on 5 μg/kg subcutaneously twice a day. He responded excellently to G-CSF, allowing him to lead a normal life for 9 years. On March 17, 1999, a surveillance bone marrow aspirate was within normal limits with a diploid male karyotype (46,XY) in 20 metaphases. On June 8, 1999, severe left otitis associated with extensive cellulitis developed on the left side of the face. Complete blood count showed hemoglobin 11.0, platelets 153 000, white blood cell count 11 800, and 32% myeloperoxidase-positive blasts. Bone marrow aspirate confirmed the diagnosis of AML with 73% blasts, myeloperoxidase positive, CD34 97.5%, CD13 92.6%, and CD33 31.4%. Cytogenetics assay showed a pseudodiploid clone 46,XY, add (18) (q23), in 18 metaphases and a diploid male karyotype 46,XY in 2 metaphases. G-CSF was discontinued, and the patient begun treatment with intravenous antibiotics. After 5 days, the infection had markedly improved and the white blood cell count gradually decreased. Because of the patient's stable clinical condition and the clearance of circulating blasts, the decision was made not to begin chemotherapy and to continue withholding G-CSF while maintaining close observation and prophylactic antibiotics. After 4 weeks without G-CSF, a repeat bone marrow aspirate documented complete morphologic and cytogenetic remission that lasted for 11 weeks, at which time the family declined bone marrow transplantation and restarted the patient on 3 μg/kg G-CSF twice a day to maintain his absolute neutrophil count in the 1000 range. A surveillance bone marrow aspirate taken 7 weeks after G-CSF was restarted showed 40% myeloperoxidase-positive blasts with reappearance of the old 18q+ clone and a new clone with trisomy 21. G-CSF administration was interrupted again, and the patient achieved a second remission in 14 days without chemotherapy. After 6 weeks in complete remission, he underwent matched, unrelated bone marrow transplantation. Six months after transplantation, the leukemia remains in remission.

Cytochemical assays, flow cytometry studies, and cytogenetic analysis were performed on bone marrow aspirates using standard methology.16 Neutrophil elastase (ELA-2) and granulocyte colony-stimulating factor receptor (G-CSF-R) were analyzed by polymerase chain reaction (PCR) and reverse transcription (RT)-PCR using genomic DNA and RNA, respectively. All 5 exons for ELA-2 were sequenced as previously reported.17 For G-CSF-R analysis, the entire intracellular domain was sequenced.

Although it allows a dramatic improvement in quality of life and survival, the prolonged use of G-CSF in children with SCN has been associated with adverse side effects that vary in severity.18 In some cases, it is difficult to determine whether the complications are associated with the underlying pathophysiology of the disease, are induced by G-CSF, or are related to a combination of both.

The greatest concern is the risk for hematopoietic malignancies. In these patients, treatment is difficult and most patients die within a few months despite the use of aggressive chemotherapy.19-22 The latest report from the Severe Chronic Neutropenia International Registry indicates that the incidence of myelodysplastic syndrome and AML is almost 9% in patients with SCN receiving G-CSF.23 Malignant myeloid disorders have not been reported11 18 in patients with idiopathic or cyclic neutropenia maintained on long-term treatment with G-CSF and followed up or the same period, indicating that the risk for leukemic transformation is probably a function of the underlying myelopoietic defect rather than a direct effect of growth-factor treatment.

The case we present here is the first to demonstrate a direct relation between G-CSF administration and blast count in a patient with SCN. In this patient, who has had SCN since infancy and who manifests the recently reported mutation of the gene for neutrophil elastase, AML developed in association with a clonal cytogenetic abnormality after 9 years of treatment with G-CSF. The patient had morphologic and cytogenetic remission on discontinuation of G-CSF, but a mutation of G-CSF-R was detectable in 2 samples from the 3-month remission period (Table 1).

G-CSF is known to mediate its effect by G-CSF-R. On ligand binding, the G-CSF-R is dimerized and stimulates cell proliferation or differentiation by activating various signaling pathways.24 Current evidence25 indicates that mutations in G-CSF-R lead to hypersensitivity to G-CSF with robust proliferation of the host cells. In this patient, we examined bone marrow by PCR and RT-PCR using G-CSF-R–specific primers. Sequencing of the corresponding PCR-amplified fragments revealed a point mutation in G-CSF-R coding region (manuscript in preparation). The same G-CSF-R mutation was detected at 2 different time points when the patient was off G-CSF (Table 1). Examination of PCR-amplified bone marrow-derived genomic DNA from this patient also revealed a point mutation in the coding region of neutrophil elastase17(Table 1).

Overt leukemia recurred 7 weeks after G-CSF treatment was resumed. Cell surface markers were identical to those at diagnosis, and cytogenetic test results confirmed the reappearance of the old abnormal clone in addition to the emergence of a new clone (Table 1). A second morphologic remission was achieved 14 days after G-CSF was again stopped, and it lasted until the patient underwent bone marrow transplantation 6 weeks later. After transplantation, both the elastase and the G-CSF-R mutations were no longer detectable (Table1).

The G-CSF expansion of the blast count in this patient is consistent with models in which selection and maturation of individual hematopoietic lineages are stimulated by hematopoietic growth factors. The mechanism that allowed this patient's leukemia to remain quiescent when pharmacologic doses of G-CSF were withdrawn deserves further study. The G-CSF-R mutation persisted despite the variations in blast count. Additional studies may clarify the relation between this mutation and the underlying mutation of the gene for neutrophil elastase in the pathophysiology of SCN. This patient did not have monosomy 7, a frequent marker of AML in patients with SCN. We recommend that in patients with congenital neutropenia and AML, G-CSF be withheld, if the clinical condition allows, so that they may be observed off G-CSF before chemotherapy is begun.

The publication costs of this article were defrayed in part by page charge payment. Therefore, and solely to indicate this fact, this article is hereby marked “advertisement” in accordance with 18 U.S.C. section 1734.

1
Kostmann
RRO
Infantile genetic agranulocytosis (agranulocytosis infantilis hereditaria): a new recessive lethal disease in man.
Acta Paediatr Scand.
45
1956
1
78
2
Wriedt
K
Kauder
E
Mauer
AM
Defective myelopoiesis in congenital neutropenia.
N Engl J Med.
283
1972
1072
1077
3
Gilman
PA
Jackson
DP
Guild
HG
Congenital agranulocytosis: prolonged survival and terminal acute leukemia.
Blood.
36
1970
576
585
4
Rosen
RB
Kang
SJ
Congenital agranulocytosis terminating in acute myelomonocytic leukemia.
J Pediatr.
94
1979
406
408
5
Wong
WY
Williams
D
Slovak
ML
et al
Terminal acute myelogenous leukemia in a patient with congenital agranulocytosis.
Am J Hematol.
43
1993
133
138
6
Rappeport
JM
Parkman
R
Newburger
P
Camitta
BM
Chusid
MJ
Correction of infantile agranulocytosis (Kostmann's syndrome) by allogeneic bone marrow transplantation.
Am J Med.
68
1980
605
609
7
Pahwar
RN
O'Reilly
RJ
Broxmeyer
HE
Smithwick
EM
Pahwa
SG
Kapadia
A
Partial correction of neutrophil deficiency in congenital neutropenia following bone marrow transplantation (BMT).
Exp Hematol.
5
1977
45
8
Bonilla
MA
Gillio
AP
Ruggeiro
M
et al
Effect of recombinant human granulocyte colony-stimulating factor on neutropenia in patients with congenital agranulocytosis.
N Engl J Med.
320
1989
1574
1580
9
Welte
K
Zeidler
C
Reiter
A
et al
Differential effects of granulocyte-macrophage colony-stimulating factor and granulocyte colony-stimulating factor in children with severe congenital neutropenia.
Blood.
75
1990
1056
1063
10
Dale
DC
Bonilla
MA
Davis
MW
et al
A randomized control phase III trial of recombinant human granulocyte colony-stimulating factor (filgrastim) for treatment of severe chronic neutropenia.
Blood.
81
1993
2496
2502
11
Boxer
LA
Dale
D
Congenital neutropenia and the risk of leukemia.
J Pediatr.
130
1997
335
336
12
Welte
K
Boxer
LA
Severe congenital neutropenia: pathophysiology and therapy.
Semin Hematol.
34
1997
267
278
13
Dong
F
Brynes
RK
Tidow
N
Welte
K
Lowenberg
B
Touw
IP
Mutations in the gene for the granulocyte colony-stimulating-factor receptor in patients with acute myeloid leukemia precededby severe congenital neutropenia.
N Engl J Med.
333
1995
487
493
14
Kabra
R
Dali
D
Freedman
M
et al
Monosomy 7 and activating RAS mutations accompany malignant transformation in patients with congenital neutropenia.
Blood.
86
1995
4579
4586
15
Germeschansen
M
Tidow
N
Pilz
C
Tschan
C
Zeidler
C
Welte
K
G-CSF receptor mutations in patients with severe congenital neutropenia: frequency and implications in leukemia development [abstract].
Blood.
94
1999
45a
16
Weinkauff
R
Estey
E
Starostik
P
et al
Use of peripheral blood blasts vs bone marrow blasts for diagnosis of acute leukemia.
Am J Clin Pathol.
111
1999
733
740
17
Dale
DC
Person
RE
Bolyard
AA
et al
Mutations in the gene encoding neutrophil elastase in congenital and cyclic neutropenia.
Blood.
96
2000
2317
2322
18
Bonilla
MA
Dale
D
Zeidler
C
et al
Long term safety of treatment with recombinant human granulocyte colony-stimulating factor (r-met HuG-CSF) in patients with severe congenital neutropenias.
Br J Haematol.
88
1994
723
730
19
Weinblatt
ME
Scimeca
P
James-Herry
A
Sahdev
I
Kocher
J
Transformation of congenital neutropenia into monosomy 7 and acute nonlymphoblastic leukemia in a child treated with granulocyte colony-stimulating factor.
J Pediatr.
126
1995
263
265
20
Imashuku
S
Hibi
S
Kataoka-Morimoto
Y
et al
Myelodysplasia and acute myeloid leukemia in cases of aplastic anemia and congenital neutropenia following G-CSF administration.
Br J Haematol.
89
1995
188
190
21
Smith
OP
Reeves
BR
Kempski
HM
Evans
JP
Kostmann's disease, recombinant HuG-CSF, monosomy 7 and MDS/AML.
Br J Haematol.
91
1995
150
153
22
Corey
SJ
Wollman
MR
Deshpande
RV
Granulocyte colony-stimulating factor and congenital neutropenia—risk of leukemia?
J Pediatr.
129
1996
187
188
23
Freedman MH, Bonilla MA, Fier C, et al. Myelodysplasia and acute myelois leukemia in patients with congenital neutropenia receiving G-CSF therapy. Blood. In press.
24
Avalos
BR
Molecular analysis of the granulocyte colony-stimulating factor receptor.
Blood.
88
1996
761
777
25
Hermans
MH
Antonissen
C
Ward
AC
Mayen
AE
Ploemacher
RE
Touw
IP
Sustained receptor activation and hyperproliferation in response to granulocyte colony-stimulating factor (G-CSF) in mice with a severe congenital neutropenia/acute myeloid leukemia derived mutation in the G-CSF receptor gene.
J Exp Med.
189
1999
683
692

Author notes

Sima Jeha, Department of Pediatrics, University of Texas M.D. Anderson Cancer Center, Box 87, 1515 Holcombe Boulevard, Houston, TX 77030; e-mail: sjeha@mdanderson.org.

Sign in via your Institution