Blood, Vol. 92 No. 8 (October 15), 1998:
pp. 2995-2997
CORRESPONDENCE
Magnetic Resonance Imaging in Myelofibrosis
 |
LETTER |
To the Editor:
The recent review about magnetic resonance imaging (MRI) of the bone
marrow in hematologic malignancies has suggested that MRI had little or
no value in the evaluation of myelofibrosis (MF).1 Although
MR findings did not also appear beneficial in the differential
diagnosis of myelofibrosis, our data showed that MRI may have some
importance in predicting the prognosis of this disorder.
Thirteen patients with MF were evaluated (11 patients with primary MF
and 2 patients with secondary MF) and diagnoses of MF were made
according to previously defined criteria.2 Before the MR
examination, bone marrow aspirates and biopsies from posterior iliac
crest were performed. Clinical prognostic staging of the patients were determined on the basis of their hemoglobin value and
percentage of white blood cell precursors in peripheral circulation, as
it has been proposed by Visani et al.2 Myelofibrosis in bone marrow biopsies were evaluated in three different stages according
to the criteria defined by Ward and Block.3
The MR investigations were performed with a 0.5-Tesla MR scanner
(Gyroscan-T5-Holland, Philips). Coronal T1-weighted
images from the lower lumbar vertebrae, sacrum, iliac wings, and
proximal femur were obtained in contiguous 5-mm slices in a 256 × 256 matrix with TR, 400 milliseconds (ms); TE, 20 ms; and a
number of signal acquisitions, 2. Short TI inversion recovery (STIR)
coronal images of the same regions were obtained in 6-mm slices in a
256 × 256 matrix with TR, 1,800 to 2,200 ms; TE, 30 to 40 ms; and T1,
140 to 150 ms. In T1-weighted images, fatty tissue with high signal intensity appeared bright, whereas cellular bone marrow had a low
signal intensity with dark appearance. In STIR sequences, the signal
from fatty bone marrow was suppressed, so that the cellular marrow was
brighter. Other MRI sequences, such as water-saturated T2-weighted
images (TR/TE: 3,200 to 5,000/102 ms; 5-mm slice thickness and 1-mm
gap; NEX: 3; and 256 × 160 matrix size), fat-saturated T2-weighted
images (TR/TE: 5,000 to 6,500/102 ms; 5-mm slice thickness and 1-mm
gap; NEX: 2; 256 × 160 matrix size), and fat-saturated T1-weighted
images (TR/TE: 360/9; 5-mm slice thickness and 1-mm gap; NEX: 3;
256 × 160 matrix size) were also used for detecting the extension
of the cellularity and the fibrosis. However, these sequences did not
provide any additional information with respect to the bone marrow
cellularity in comparison with the STIR techniques. MR sequences were
classified according to the bone marrow cellularity, resting fatty
marrow, and marrow fibrosis. The patterns were categorized as follows.
Pattern Ia.
Low signal intensity in iliac wings and lower lumbar vertebrae and high
signal intensity in femoral epiphysis and/or thoracanteric region in T1-weighted images and high signal intensity in all STIR
sequences were accepted as pattern Ia. That pattern was compatible with
hypercellular bone marrow and early phase MF.
Pattern Ib.
Low signal intensity in all regions with T1-weighted images and high
signal intensity in STIR sequences were also defined to be compatible
with hypercellular bone marrow and early phase MF. Although pattern Ia
and Ib were comparable in predicting the phase of MF, pattern
Ia images also advocated still remaining fatty bone marrow, especially
in the femoral epiphyses.
Pattern II.
Low signal intensity was apparent in all regions both in T1-weighted
images and in STIR sequences. That pattern was accepted to predict late
phase MF with extended fibrosis and low hematopoietic activity.
Correlation between the MRI patterns and prognostic staging,
histopathologic staging, and serum LDH levels were
determined by Spearman test.
The results are summarized in Table 1.
Histopathologic staging in MF according to bone marrow biopsies was not
found to be correlated with clinical prognostic staging and MRI
findings (P > .05), as it has been reported by Varki et
al.4 However, defined MRI patterns were well correlated
with the prognostic staging and serum LDH levels (P = .026
and P = .007, respectively). Kaplan et al5
suggested that MRI findings in MF could characterize the phase,
severity, and progression of the disease, but that controversial data
assessed correlation between the MRI findings, serum LDH levels, and
spleen size. However, in our study, we evaluated this correlation with
a confirmed clinical prognostic staging.2
In conclusion, MRI appeared as a useful and noninvasive method for the
determination of phase and severity of MF, and the defined MRI patterns
were comparable with the clinical prognostic staging.
Önder Alpdo
an
Department of Hematology
SSK Okmeydani
Hospital
Istambul, Turkey
Tülin Budak-Alpdoan
Mahmut Bayik
Tevfik Akolu
Department of Hematology
Nihat Kodalli
Nevzat Gürmen
Department of
Radiology
Marmara University Hospital
Istambul,
Turkey
| |
REFERENCES |
1.
Moulopoulos LA,
Dimopoulos MA:
Magnetic resonance imaging of the bone marrow in hematologic malignancies.
Blood
90:2127,
1997[Free Full Text]
2.
Visani G,
Finelli C,
Castelli U,
Petti MC,
Ricci P,
Vianelli N,
Gianni L,
Zuffa E,
Aloe Spiriti MA,
Latagliata R,
Pileri S,
Magrini U,
Gugliotta L,
Morra E,
Bernasconi C,
Mandelli F,
Tura S:
Myelofibrosis with myeloid metaplasia: Clinical and haematological parameters predicting survival in a series of 133 patients.
Br J Haematol
75:4,
1990[Medline]
[Order article via Infotrieve]
3.
Ward HP,
Block MH:
The natural history of agnogenic myeloid metaplasia (AMM) and critical evaluation of its relationship with the myeloproliferative syndrome.
Medicine
50:357,
1971[Medline]
[Order article via Infotrieve]
4.
Varki A,
Lottenberg R,
Griffin R,
Reinhard E:
The syndrome of idiopathic myelofibrosis: Clinicopathologic review with emphasis on the prognostic variables predicting survival.
Medicine (Baltimore)
62:353,
1983[Medline]
[Order article via Infotrieve]
5.
Kaplan KR,
Mitchell DG,
Steiner RM,
Murphy S,
Vinitski S,
Rao VM,
Burk DL,
Rifkin MD:
Polycytemia vera and myelofibrosis: Correlation of MR imaging, clinical and laboratory findings.
Radiology
183:329,
1992[Abstract/Free Full Text]
| |
RESPONSE |
Dr Alpdogan et al studied 13 patients with myelofibrosis with magnetic
resonance (MR) images of the lower lumbar spine, pelvis, and proximal
femurs. They concluded that MR patterns derived from changes in the
normal appearance of the bone marrow in the above areas correlated with
serum LDH levels and with the clinical prognostic staging of the
disease but not with the histopathologic staging. Kaplan et
al1 in 1992 reported similar findings in 14 patients with
chronic myeloproliferative disease; they found that absence of fatty
marrow in both the greater trochanter and femoral capital epiphysis was
associated with significantly higher serum LDH values and lower serum
cholesterol values. Alpdogan et al studied a larger number of patients
with myelofibrosis and included findings on STIR images that may help
differentiate hypercellular from fibrotic marrow.
In our review on hematologic malignancies of the bone marrow, the data
of Kaplan et al1 are discussed in detail in the chapter on
"Miscellaneous malignant bone marrow disorders."2 I
believe that there is no doubt that myelofibrosis cannot be distinguished from other hematologic malignancies based on
morphological changes on MR images of the bone marrow. It is also well
established by now that MR images, by providing the opportunity to
examine a large volume of the bone marrow, may complement the bone
marrow biopsy in assessing the extent, severity, and prognosis of most of the hematologic malignancies. However, before bone marrow MR imaging
is used to replace some of the repeated bone marrow biopsies that
patients with myeloproliferative diseases require, it is my opinion
that larger numbers of patients need to be studied and that research
should be guided towards obtaining quantitative measurements that can
serve as more accurate indices of tumor burden.
Lia A. Moulopoulos
Department of Radiology
Areteion Hospital
Athens,
Greece
| |
REFERENCES |
1.
Kaplan KR,
Mitchell DG,
Steiner RM,
Murphy S,
Vinitski S,
Rao VM,
Burk DI,
Rifkin MD:
Polycythemia vera and myelofibrosis: Correlation of MR imaging, clinical and laboratory findings.
Radiology
183:329,
1992
2.
Moulopoulos LA,
Dimopoulos MA:
Magnetic resonance imaging of the bone marrow in hematologic malignancies.
Blood
90:2127,
1997
