Granulocytic_sarcoma

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Granulocytic sarcoma
Cranial and breast involvement
Suat Fitoza,*, Çetin Atasoya, Kivilcim Yavuza, Sevgi Gozdasoglub,
Ilhan Erdena, Serdar Akyara
aDepartment of Radiology, Medical School, Ankara University, Ibn-i Sina Hospital, 06100 Sihhiye, Ankara, Turkey
bDepartment of Pediatric Oncology, Medical School, Ankara University, 06100 Dikimevi, Ankara, Turkey
Received 10 September 2001
Abstract
The term granulocytic sarcoma designates an infrequent solid tumor composed of aggregates of immature granulocytic precursors in
extramedullary sites. The lesion generally occurs either during the natural course of acute myelogenous leukemia or after a remission has
been achieved; however, it may rarely represent the initial manifestation of the disease. We present radiologic features of cranial and breast
involvement of granulocytic sarcoma in a 13-year-old female with acute myelogenous leukemia. The cranial lesion appeared nearly
isointense with cortical gray matter on T1- and T2-weighted magnetic resonance (MR) images, and enhanced homogeneously after the
injection of gadolinium. MRI showed a well-delineated lobulated mass in the left breast, which had a heterogeneous hyperintense signal and
remarkable contrast enhancement. D 2002 Elsevier Science Inc. All rights reserved.
Keywords: Granulocytic sarcoma; Breast; Cranium; Computed tomography; Magnetic resonance imaging
1. Introduction
Granulocytic sarcoma, also known as chloroma, is a
solid tumor composed of premature precursors of the
granulocytic series [1]. The etiology and incidence of these
lesions remains unknown. The term chloroma has been
used to describe the green color on cut sections of the
tumor, which is caused by the activity of the myeloperox-
idase enzyme [2–4]. When the lesions are nonpigmented,
they are called granulocytic sarcomas or myeloblatomas
[4]. Although these lesions commonly present during
active disease or relapses of the acute or chronic myelog-
enous leukemia, they occasionally precede other systemic
manifestations of the disease [1,5]. Granulocytic sarcomas
may affect virtually any part of the body [1,6]. In the
central nervous system, they preferentially involve the dura
and orbits [3,5]. Breast involvement is very rare and the
mammographic and ultrasonographic findings, which have
been described in a few cases, are not specific for this
tumor [7]. We present CT and magnetic resonance (MR)
findings of the dural lesion and ultrasonographic and MR
features of the breast involvement in a pediatric case with
acute myelogenous leukemia.
2. Case report
A 13-year-old girl was admitted with inability to close
her left eye, left-sided otalgia, and swelling in her left
breast. History revealed an operation for a lumbar mass
3 years ago, when she was diagnosed to have acute
myelogenous leukemia. Systemic chemotherapy and local
spinal irradiation provided a state of remission for about
1 1/2 years, after which the abovementioned symptoms
appeared. Physical examination revealed left-sided peri-
pheral facial paralysis and 10-cm lobulated mass in the left
breast. Complete blood count showed anemia, thrombocy-
topenia, and leukocytosis. Bone marrow aspiration showed
almost total replacement by blastic cells. Cerebrospinal
fluid examination was consistent with meningeal involve-
ment. Cranial CT demonstrated a homogeneously enhan-
0899-7071/02/$ – see front matter D 2002 Elsevier Science Inc. All rights reserved.
PII: S0899 -7071 (01 )00388 -6
* Corresponding author. Ankara Universitesi Tip Fakultesi, Cebeci
Kampusu, Radyoloji Bolumu, 06100 Dikimevi, Ankara, Turkey. Tel.: +90-
312-4910-646; fax: +90-312-3107-117.
E-mail address: sfitoz@ato.org.tr (S. Fitoz).
Journal of Clinical Imaging 26 (2002) 166–169
cing 3.5-cm extraaxial mass in the left temporal region
(Fig. 1). The dural base of the lesion was better delineated
by MR imaging, where the lesion appeared almost iso-
intense with the cortical gray matter with slight central
hypointensity on T1- and T2-weighted sequences and
enhanced densely and homogeneously on postgadolinium
images (Figs. 2–4). Ultrasonography showed a large mass
in the left breast with lobulated contours and heterogen-
eous echo texture, which was quite vascular on the color
mode (Fig. 5). The lesion was more hyperintense than
muscle on T1- and T2-weighted MR images (Figs. 6
and 7), the hyperintensity being more prominent on the
T2-weighted sequences. Intravenous injection of gadolin-
ium caused patient discomfort and nausea, which pre-
cluded evaluation of dynamic enhancement pattern of the
lesion. On delayed postcontrast images the lesion showed a
markedly heterogenous enhancement (Fig. 8). Fine needle
aspiration biopsy of the breast mass confirmed granulo-
cytic sarcoma. Both lesions regressed considerably after a
1-month course of intensive chemotherapy.
3. Discussion
Granulocytic sarcomas develop as a consequence of
migration and proliferation of leukemic cells in extrame-
dullary sites [6]. Premature cells derived from the hemato-
poietic precursors bind to fibroblasts preferentially in the
nonhematopoietic tissues and initiate myeloid metaplasia
[6]. Leukemic states, particularly acute myelogenous leu-
kemia, are the most frequent predisposing conditions;
however, they may rarely occur in myelodysplastic syn-
dromes [1,6]. Although long-term survival has occasion-
ally been achieved, the prognosis of granulocytic
sarcomas is generally poor, particularly when they occur
during remissions [6].
Fig. 2. The mass is nearly isointense with gray matter on T1-weighted
axial MR image. Displacement of the brain parenchyma suggests
extraaxial location.
Fig. 3. On T2-weighted image, the mass slightly more hyperintense than the
white matter and isointense with the gray matter excluding the central
hypointense region.
Fig. 4. Contrast-enhanced T1-weighted coronal image better shows
the extraaxial location of the lesion, which displays uniform and
dense enhancement.
Fig. 1. Contrast-enhanced CT shows a densely enhancing homogeneous
mass in the left temporal region.
S. Fitoz et al. / Journal of Clinical Imaging 26 (2002) 166–169 167
Granulocytic sarcomas may rarely appear de novo,
without evidence of systemic illness. Even then, they are
thought to represent the first sign of the systemic illness,
which heralds progression of a full-blown disease [6]. The
absence of systemic signs and symptoms of the disease
makes these lesions a real diagnostic challenge. Even the
cythopathologist may find it difficult to differentiate them
from the anaplastic non-Hodgkin’s lymphomas and carci-
nomas, especially when cytoplasmic granulation and eosi-
nophilic myelocytes are absent [8]. Immunohistochemical
techniques are required in such cases [1].
Granulocytic sarcomas may affect any part of the body
[1,6]. CNS involvement predominates in females, and
usually develops months to years after a complete remission
has been achieved, either de novo, or, more commonly, via
perivascular infiltration of the blasts through the arachnoid
venules [9]. The skull and meninges are the preferred
intracranial sites [3]. Not all intracranial granulocytic sar-
comas are extraaxial; very rarely the lesions may be intra-
parenchymal [5]. Intracranial granulocytic sarcomas
frequently appear hyperdense on unenhanced CT [3,9].
After the injection of contrast medium they may enhance
either homogeneously or their central parts may remain
relatively hypodense [9]. However, lesions with ring
enhancement have also been reported [10]. Their CT
appearance mimics that of meningiomas, lymphomas, and
metastases [4,9]. The signal intensity of central nervous
system lesions is mostly hypo- or isointense on T1- and T2-
weighted MR images [9], but T2-hyperintensity is also not
uncommon [3]. Gadolinium injection causes a marked
homogenous enhancement [9]. Should the lesion be extra-
axial and isointense with the cortical gray matter on all
pulsesequences, one cannot confidently rule out meningi-
omas from the differential diagnosis. However, absence of
intralesional calcification and hyperostotic bone changes
may be helpful in distinguishing granulocytic sarcomas
from meningiomas [9].
Fig. 6. On T2-weighted axial MR image the left breast is almost totally
involved by a slightly hyperintense mass with regions of low and high
signal intensity.
Fig. 7. T1-weighted image shows the mass to be slightly hyperintense than
the chest wall musculature.
Fig. 8. On the postgadolinium image the mass shows dense and
heterogeneous enhancement. Also note increased vascularity at the
periphery of the lesion, which is sharply demarcated from the
surrounding parenchyma.
Fig. 5. Power Doppler breast ultrasonography shows a heterogenous
hyperechogenic lesion, which is hypervascular and contains high-resistance
arterial flow.
S. Fitoz et al. / Journal of Clinical Imaging 26 (2002) 166–169168
Granulocytic sarcoma of the breast has been described in
a few reports previously [1,7,11,12]. Mammography has
shown them as solitary or multiple noncalcified masses with
well or poorly defined margins [12]. Only a few reports
have described the ultrasonographic features of these lesions
[7,11], which are rather nonspecific and include homoge-
neously hypoechoic masses, hypoechoic masses with cent-
ral echogenicity, and heterogeneously hypoechoic lesions
with or without acoustic shadowing [7]. Our patient’s breast
mass was slightly more echogenic than the surrounding
glandular tissue and had a heterogeneous texture. The large
size of the lesion precluded evaluation of distal acoustic
changes. Color Doppler examination showed marked vas-
cularity in the lesion.
As far as we are aware, MR imaging has not been
employed in the evaluation of the breast lesions. In our
patient, the lobulated mass could be clearly delineated from
the surrounding parenchyma and had a heterogeneous signal
intensity, which was higher than the chest wall musculature
on T1- and T2-weighted images. On delayed postgadoli-
nium images, the lesion enhanced dramatically and in a
heterogeneous manner with nonvascular central parts prob-
ably representing necrosis and degeneration. MR images
also disclosed vascular structures at the periphery of and
inside the lesion.
MR features of an ovarian granulocytic sarcoma have
been described [13]. T2-weighted hypointensity observed in
the lesion has been attributed to high levels of myeloper-
oxidase, an iron-containing enzyme, normally found in
white blood cells [13,14]. Unlike these previous observa-
tions, the breast lesion in our patient displayed as hyper-
intense signal on T2-weighted images. Although the MR
appearance of the breast mass was not specific, invasive
ductal carcinoma and lobular invasive carcinoma, which
tend to affect older patients and have irregular spiculated
contours, could be easily ruled out. The differential dia-
gnosis of well-defined solid breast lesions include medul-
lary invasive cancer, fibroadenoma, and metastases.
Medullary cancer is also infrequent in the pediatric age
group. While they do not have a widely accepted classical
MR appearance on delayed postcontrast images, fibroade-
nomas tend to have a homogenous internal architecture [15].
Rarely, fibroadenomas can display characteristic internal
septations, which reliably distinguish them from well-mar-
ginated breast lesions [15]. In summary, granulocytic sar-
comas may affect a small minority of patients with acute
myelogenous leukemia. The radiologic, and even the patho-
logic, diagnosis may prove challenging when they are the
sole manifestation of the disease. A correct diagnosis by
radiological means, or at least inclusion of the lesion into
the differential diagnosis, may save these patients from
unnecessary operation. Gadolinium-enhanced MR images
can delineate the markedly enhancing well-marginated
lesion from the dense fibroglandular tissue in young females
who are not suited for mammography.
References
[1] Mwanda WO, Rajab JA. Granulocytic sarcoma: report of three cases.
East Afr Med J 1999;76:594–6.
[2] Sham RL, Phatak PD, Kouides PA, Janas JAS, Marder VJ. Hemato-
logic neoplasia and central nervous system. Am J Hematol 1999;62:
234–8.
[3] Donovan WD, Govoni AF. An 11-year-old boy with a history of AML
and new onset of headaches. Clin Imaging 1992;16:272–6.
[4] Pomeranz SJ, Hawkins HH, Towbin R, Lisberg WN, Clark RA. Gran-
ulocytic sarcoma (chloroma): CT manifestations. Radiology 1985;
155:167–70.
[5] Fruauff AA, Barasch ES, Rosenthal A. Solitary myeloblastoma pre-
senting as acute hydrocephalus: review of literature, implications for
therapy. Pediatr Radiol 1988;18:369–72.
[6] Békássy AN, Hermans J, Gorin NC, Gratwohl A. Granulocytic sarco-
ma after allogeneic bone marrow transplantation: a retrospective Euro-
pean multicenter survey. Bone Marrow Transplant 1996;17:801–8.
[7] Son HJ, Oh KK. Multicentric granulocytic sarcoma of the breast:
mammographic and sonographic findings. AJR, Am J Roentgenol
1998;171:274–5.
[8] Pettinato G, Chiara A, Insabato L, Renzo A. Fine needle aspiration
biopsy of a granulocytic sarcoma (chloroma) of the breast. Acta Cytol
1988;32:67–71.
[9] Sham RL, Phatak PD, Kouides PA, Janas JAS, Marder VJ. Hemato-
logic neoplasia and the central nervous system. Am J Hematol 1999;
62:234–8.
[10] Glass JP, Tassel PV, Keating MJ, Cork A, Trujillo J, Holmes R.
Central nervous system complications of a newly recognized subtype
of leukemia: AMML with a pericentric inversion of chromosome 16.
Neurology 1987;37:639–44.
[11] Ahrar K, McLeary MS, Young LW, Masotto M, Rouse GA. Granulo-
cytic sarcoma (chloroma) of the breast in an adolescent patient: ultra-
sonographic findings. J Ultrasound Med 1998;17:383–4.
[12] Barloon TJ, Young DC, Bass SH. Multicentric granulocytic sarcoma
(chloroma) of the breast: mammographic findings. AJR, Am J Roent-
genol 1993;161:963–4.
[13] Jung SE, Chun KA, Park SH, Lee EJ. MR findings in ovarian gran-
ulocytic sarcoma. Br J Radiol 1999;72:301–3.
[14] Parker K, Hardjasudarma M, McClellan RL, Fowler MR, Milner JW.
MR features of an intracerebellar chloroma. Am J Neuroradiol 1996;
17:1592–4.
[15] Kuhl CK. MRI of breast tumors. Eur Radiol 2000;10:46–58.
S. Fitoz et al. / Journal of Clinical Imaging 26 (2002) 166–169 169