|Year : 2016 | Volume
| Issue : 2 | Page : 64-75
Role of MRI in the diagnosis of bone marrow infiltrative lesions
Amany El Kharboutly MD , Diaa El Deep
Department of Radiology Banha University, Banha, Egypt
|Date of Submission||01-Feb-2016|
|Date of Acceptance||04-Feb-2016|
|Date of Web Publication||29-Aug-2016|
Amany El Kharboutly
Villa 183, Street 4, Banha El Gedida, Banha
Background and aim
MRI can detect intramedullary infiltration in a highly advanced manner. It is also useful for the detection of tumor extension, associated soft tissue masses, and neurological compromise. MRI can increase the rate of successful bone marrow biopsies as it can assess a large volume of bone marrow noninvasively and relatively quickly. The aim of this study was to assess the role of MRI in the evaluation of bone marrow infiltrative lesions.
Patients and methods
This study included 30 patients with bone marrow infiltrative lesions: 14 male and 16 female patients. The ages of the patients ranged from 8 to 75 years (mean 41.5 years). Pain was the most common symptom in the studied cases, followed by swelling. The patients in our study were examined by means of plain radiography (15 cases), computed tomography (five cases), isotopic bone scan (one case), and MRI (all cases).
According to the pathological and radiological results, the lesions in our study were classified as follows: metastasis (12 cases); plasma cell dyscrasias (eight cases), including multiple myeloma (six cases) and plasmacytoma (two cases); lymphoma (seven cases), including non-Hodgkin’s lymphoma (five cases) and Hodgkin’s lymphoma (two cases); Ewing’s sarcoma (two cases); and leukemia (chronic lymphatic leukemia) (one case).
MRI is a sensitive method for detection of areas of marrow infiltration. The value of MRI lies in its ability to document the presence and extent of disease and to determine an appropriate radiation field.
Keywords: bone marrow, lymphoma, MRI, multiple myeloma
|How to cite this article:|
El Kharboutly A, El Deep D. Role of MRI in the diagnosis of bone marrow infiltrative lesions. Tanta Med J 2016;44:64-75
| Introduction|| |
MRI has become the preferred method over other imaging modalities in evaluating disease in the bone marrow. It is a noninvasive technique that complements bone marrow aspirations and biopsies by sampling a large volume of bone marrow and by providing information that aids the diagnosis, staging, and follow-up .
A wide variety of disorders alter the marrow by infiltrating or replacing normal components. Included in this group are neoplastic processes, inflammatory conditions, myeloproliferative disorders, lipidoses, and histiocytoses. The effect of these different processes on marrow signal patterns depends largely on the type of cells or tissues infiltrating the marrow and the degree of cellularity of the process. Other factors affecting the signal patterns include hemorrhage, necrosis, fibrosis, sclerosis, and inflammatory debris with associated water content or edema .
Neoplastic processes, whether primary or metastatic, alter the marrow by infiltration. With rare exception, tumor cells have long T1 values and variable T2 values. Measured T1 and T2 relaxation times for a spectrum of infiltrative processes have demonstrated no reliable value for identification of specific histological types or for differentiating benign from malignant tumors . However, in certain settings (e.g. leukemia) when the diagnosis is established, sequential measurement of T1 relaxation values may be helpful for documentation of new disease, remission, and relapse .
MR signal characteristics of infiltrative marrow lesions vary. However, all demonstrate a degree of decreased signal intensity (SI) on T1-weighted images (WI), as stated by Cohen and colleagues ,, which makes them conspicuous within the higher SI of surrounding fatty marrow, with the exception of melanoma and, rarely, myeloma. Melanoma, in contrast, can demonstrate increased signal on T1-WI presumably resulting from the paramagnetic effect of melanin. The mechanism by which myeloma can cause increased T1 signal is unclear .
T2 SI behaviors of infiltrative processes are much more variable than their corresponding T1 SI behaviors. Although most infiltrative disorders demonstrate some prolongation of T2 relaxation that causes them to appear higher in SI than the surrounding marrow, many do not. This variability results not only from the unique tumor cell but also from its degree of cellularity, water content, and complicating or associated factors (sclerosis, fibrosis, necrosis, hemorrhage, and inflammatory debris). Other pulse sequences (e.g. STIR) may demonstrate subtle T1 and T2 relaxation differences not apparent on spin-echo images; yet, even these sequences may not differentiate some neoplastic cells from normal hematopoietic marrow .
Diffuse or focal involvement of bone marrow with tumor may be due to plasma cell myeloma, leukemia, lymphoma, primary bone neoplasm, or metastatic disease .
| Patients and methods|| |
This study included 30 patients: 14 male and 16 female patients. Their ages ranged from 7 to 75 years (mean 41 years).
Thirty patients with bone marrow infiltrative lesions were referred to the MRI Unit in Radiodiagnosis Departments, mostly of Mansoura University, Nasser Institute Hospital, and to other private centers, from May 2009 to June 2012.
Each patient was subjected to the following:
- Clinical assessment including history taking (patient’s age, the complaint, other symptoms) and physical examination, which was carried out by our colleagues in the referring departments or outpatient clinics.
- Radiological assessment:
This included the following:
- Plain radiography:
This was the primary and initial step in the radiological assessment. Routine anteroposterior and lateral views were taken for the region of clinical suspicion in 15 patients.
- Computed tomography:
Axial computed tomography scan was taken for five patients.
- Isotope bone marrow scanning:
This was carried out for one patient.
This was carried out for all patients.
Axial T1-WI in 21 cases.
Axial T1-WI postcontrast in 17 cases.
Axial T2-WI in 15 cases.
Axial STIR in 10 cases.
Sagittal T1-WI in 21 cases.
Sagittal T2 in 17 cases.
Sagittal T1-WI postcontrast in 12 cases.
Sagittal STIR in 10 cases.
Coronal T1 in 12 cases.
Coronal T1-WI postcontrast in seven cases.
Coronal T2-WI in seven cases.
Coronal STIR in eight cases.
It was performed in 22 cases after injection of Gd-DTPA at a dose of 0.1mmol/kg. T1-WI was taken immediately thereafter in different planes.
- Pathological assessment:
Operative biopsy was performed for 18 patients and needle aspiration biopsy for 11 patients. The specimen was fixed in 10% neutral formalin and sent to the pathologist. One case of leukemia was diagnosed on the basis of blood profile.
| Results|| |
This study included 30 patients with bone marrow infiltrative lesions: 14 male and 16 female. Their ages ranged from 7 to 75 years (mean 41 years). Among the 30 cases studied, metastatic disease was the most common (40%), followed by lymphoma (23.3%) and multiple myeloma (20%) ([Table 1] and [Table 2]).
|Table 2 Age and sex distribution of our cases of infiltrative bone marrow disorders|
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The primary sites of malignancy in 12 cases of metastatic disease were as follows: breast cancer (six cases), colon cancer (two cases), prostate cancer (two cases), thyroid carcinoma (one case), and bronchogenic carcinoma (one case) [Table 3]. Most of the cases showed more than one vertebral region to be involved; in two cases there was involvement of more than one region of the spine. In our study first the dorsal and then the lumbar regions were the most commonly involved metastatic regions of the spine. The posterior neural elements were also commonly involved.
MRI SI in 12 cases of disease at different sequences was as follows: on T1-WI, nine cases were hypointense, two cases showed intermediate SI, and one case showed hyperintense SI; no cases were isointense SI. On T2-WI most cases were hyperintense (10 cases), one case showed intermediate SI, and one case showed hyperintense SI; no cases were isointense SI. After contrast administration in eight cases, seven cases showed mild enhancement and one case showed moderate enhancement. The pattern of lesion was homogenous in five cases and heterogenous in seven cases. Most of the cases showed more than one finding. Vertebral collapse was seen in five cases, intraspinal masses in eight cases, paraspinal masses in seven cases, and masses related to the iliac bone in three cases ([Table 4] and [Table 5]).
MRI SI in seven cases of lymphoma at different sequences was at follows: on T1-WI, six cases were hypointense and one case was hyperintense SI. All cases on T2 WI were hyperintense (seven cases). After contrast administration in five cases, four cases showed mild enhancement and one case showed moderate enhancement. The pattern of lesion was homogenous in two cases and heterogenous in five cases. Vertebral collapse was seen in one case, intraspinal masses in three cases, paraspinal masses in one case, and masses related to the iliac bone in one case ([Table 6] and [Table 7]).
The MRI SI and pattern of involvement in six cases of multiple myeloma, two cases of plasmacytoma, two cases of Ewing’s sarcoma, and one case of leukemia (chronic lymphatic leukemia) are shown in [Table 8],[Table 9],[Table 10],[Table 11],[Table 12],[Table 13].
|Table 12 MRI signal intensity and findings in two cases of Ewing’s srcoma|
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|Table 13 MRI signal intensity and pattern of involvement in one case of leukemia (chronic lymphatic leukemia)|
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| Discussion|| |
MRI has opened new doors into the evaluation of bone marrow diseases. It allows direct visualization of the bone marrow and can depict a wide range of focal or diffuse signal alterations in the bone marrow ,.
Metastatic bone tumors
Our study included 12 cases of metastatic bone disease. It was the largest group among the studied cases. This is in agreement with the reports of Yochum and Rowe , who stated that metastatic bone tumors are the most common malignant tumors of the skeleton. The overall incidence of metastases has increased in recent years because cancer patients survive for longer intervals as a result of improved treatment regimens  ([Figure 1] and [Figure 2]).
|Figure 1 A 70-year-old male patient complaining of low back pain and limitation of movements of the right lower limb. Diagnosis: metastasis. Sagittal T1-WI shows low signal intensity of D2 vertebral body and its right posterior neural arch (more marked on the right side) as well as the right posterior neural arch of D1 vertebra. Axial T1-WI shows marked bony expansion of the right posterior neural arch and intraspinal extension. Axial T2-WI shows the mass lesion displaying high signal intensity. WI, weighted image.|
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|Figure 2 A 40-year-old male patient complaining of chronic pelvic pain. Diagnosis: metastasis. Axial T1-WI of the pelvis shows destructive bony lesion of the left iliac bone displaying intermediate SI and large lobulated soft tissue lesion filling the pelvic cavity bilaterally displaying low SI. The uterus and urinary bladder are squeezed anteriorly and to the right. Axial T2-WI shows high SI of the left iliac bone destructive lesion and low SI soft tissue lesion filling the pelvic cavity bilaterally. Coronal T1-WI shows intermediate SI of the left iliac bone destructive lesion and low SI soft tissue lesion filling the pelvic cavity bilaterally. SI, signal intensity; WI, weighted image.|
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The most common primary sites of skeletal metastases are the breast, lung, prostate, kidney, thyroid, and bowel . In our series, breast cancer is the most common primary source of skeletal metastases, representing six out of 12 cases. This is in agreement with the reports of Gold et al. , Byrne and Waxman , and Asdourian .
Our study included eight female patients with metastatic bone disease. In six of them the primary was breast cancer (75%). This is in agreement with the reports of Yochum and Rowe .
The most common bones involved in descending order are the thoracolumbar spine and sacrum, pelvis, ribs, sternum, proximal femoral and humeral shafts, and the skull . In our study, nine of 12 cases with skeletal metastases show spinal involvement (75%). Dorsal vertebral metastases were seen in seven cases, lumbar metastases in three cases, and cervical spine metastasis in one case. Also, the posterior neural elements were commonly involved in dorsal and lumbar metastasis. Pelvic metastases were seen in three cases: in the iliac bone in two cases and in the pubic bone in one case.
Yochum and Rowe  reported that metastases to the bone tend to be multiple. In our study six cases showed multiple bony metastatic lesions, whereas in three cases there were single bony metastatic lesions.
Spinal metastases begin in the vertebral body, often in the posterosuperior aspect of the vertebra. Although destruction of a pedicle is a common finding on plain films, this typically results from extension of metastatic disease in the posterior aspect of the vertebral body rather than originating within the pedicle . Our findings in cases of metastases are in agreement with what is reported by Algra et al.  as we found posterior neural element involvement in five of nine cases, and in all of them we found that the vertebral bodies were also involved.
Algra et al.  described four MRI patterns of metastases. Focal lytic lesions usually demonstrate decreased signal on T1-WI and increased signal on T2-WI (or T2* gradient echo images) compared with normal marrow. Focal blastic lesions demonstrate decreased signal on both T1-WI and T2-WI. Diffuse inhomogenous or diffuse homogenous patterns are the other two patterns. In our series, focal lytic pattern is the most common pattern of bone marrow involvement seen in cases of metastatic bone disease (nine cases) (75%). Focal blastic pattern was seen in one case (8.3%), diffuse inhomogenous pattern was seen in one case, and diffuse homogenous pattern was not encountered in our study. This is in agreement with the results of Greenfield and Arrington , who reported that osteolytic metastasis is the most common type of metastasis. Yochum and Rowe  also said that osteolytic metastases represent ∼75% of all metastatic lesions, osteoblastic metastases represent ∼15% of all lesions, and mixed lesions represent ∼10% of all metastatic deposits.
In our series, most of the cases of metastatic diseases demonstrated low SI on T1-WI (nine of 12 cases) (75%), one case showed hyperintense signal (8.3%), and two cases showed intermediate signal (16.6%). On T2-WI, most of the cases of metastatic diseases demonstrated high SI (10 of 12 cases) (83.3%), one case showed low SI (8.3%), and one case showed intermediate signal (8.3%). We also observed that some cases showed variability in the SI from lesion to lesion in the same patient. In T1 postcontrast WI, most of the cases showed mild contrast enhancement (seven of eight cases) and one case showed moderate contrast enhancement. These results are in agreement with those of Enzmann and Delapaz , Frank et al. , and Volger and Murphy .
Volger and Murphy  stated that metastases characteristically demonstrate decreased SI on T1-WI compared with the skeletal muscle and the disc, with the exception of melanoma or tumors with hemorrhage components, which may demonstrate increased signal on T1-WI. Enzmann and Delapaz  and Frank et al.  stated that the SI of metastases is variable on T2-WI and ranges from low signal (blastic metastases), to isointensity in the adjacent marrow, to high SI.
Traill et al.  stated that MRI is particularly useful for imaging the spine in the case of metastatic disease, because vertebral bodies and paraspinal and intraspinal soft tissues can be evaluated, providing a noninvasive method for detection of spinal cord compression. MRI is also useful in discriminating between benign and malignant vertebral collapse.
In our study, cases of metastatic bone disease showed vertebral collapse in five of nine cases of spinal metastases (55.5%). Most of the cases (four of five cases) had collapse of one vertebra. There are intraspinal soft tissue masses in eight cases (88.8%) and paraspinal soft tissue masses in seven cases (77.7%). Cord compression was seen in seven cases (77.7%), thecal compression in two cases (22.2%), and nerve root compression in four cases (44.4%). Infiltration of surrounding muscles was seen in four cases. Lymph node enlargement was seen in two cases. Amour et al.  reported that the vast majority of cases with cord compression are due to vertebral involvement with extension into the spinal canal. Kostuik and Weinstein  reported that cord compression occurs in 5–20% of cancer patients with metastatic disease.
Skeletal involvement may occur in both Hodgkin’s and non-Hodgkin’s lymphoma (NHL) and may arise in the bone marrow as a true primary disease. More often, the marrow is involved as a part of a disseminated disease process , [Figure 3].
|Figure 3 A 45-year-old male patient complaining of chronic cervical pain. Diagnosis: non-Hodgkin’s lymphoma. Sagittal T1-WI shows marked compression of the vertebral body of C3 displaying intermediate signal intensity. Note the large extraosseous prevertebral soft tissue mass lesion. Sagittal T2-WI shows intermediate signal intensity. Note the large extraosseous prevertebral soft and intraspinal extension. Axial T1-WI shows large extraosseous soft tissue mass lesion markedly attenuating the hypopharyngeal air column. WI, weighted image.|
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In our series, the spine was the most common site of involvement in HL cases. The spine was involved in the two cases of HL. In NHL the long bones were involved in three cases, the spine in one case, and the shoulder bones in the other case. Mac Vicar and Husband  stated that NHL tends to involve the axial skeleton. Yochum and Rowe  mentioned that the primary site of skeletal involvement in Hodgkin’s lymphoma is the vertebral body. The lower thoracic and upper lumbar spine is the target region.
In our study, most of the cases of lymphoma showed decreased T1-WI SI (six of seven cases, representing 85.7% of cases). On T2-WI, all cases (seven cases) showed hyperintense SI (100%). Contrast media was used in five patients. On T1 postcontrast series most of the cases (four of five cases, 80%) showed mild contrast enhancement. In one case there was moderate contrast enhancement (one of five cases, 20%). This is in agreement with the results of Amour et al. , who stated that the MRI SI characteristics of lymphomatous tissue in general are similar to those of other solid neoplasms, with a relatively long T1 and T2, showing relatively low SI on T1-WI with moderately to markedly increased T2 SI, although we have noted several exceptions with decreased T2 signal and increased TI SI. Our T1-WI and T2-WI findings are in agreement with those reported by Amour and colleagues. These results are also in agreement with those of Moulopoulos and Dimopoulos , who stated that after intravenous administration of contrast, the abnormal lymphomatous marrow enhances.
In our study, all cases showed focal pattern of marrow involvement. This is in agreement with the results of Linden et al.  and Edeiken-Monroe et al. , who said that lymphoma tends to form focal tumor nodules unlike leukemia. In contrast, Hoane et al.  reported that, on T1-WI MR images, lymphomatous involvement of the bone marrow is seen as diffuse, primarily heterogenous replacement of the marrow and less frequently as focal marrow lesions.
Yochum and Rowe  stated that spinal involvement in lymphoma usually causes vertebral collapse. In our series, vertebral collapse was seen in only one of three cases of spinal involvement (33.3%). Other MRI findings in our cases include intraspinal masses in three cases of spinal involvement (100%), paraspinal mass in one case (one of three cases, 33.3%), soft tissue mass related to the shoulder bones in one case, soft tissue mass related to the ulna in one case, and soft tissue mass related to the femur in one case (one of two cases of femur involvement) (50%).
Plasma cell dyscrasias
Our study includes eight patients with plasma cell dyscrasias: six with multiple myeloma and two with solitary plasmacytoma. Plasma cell dyscrasias constitute the second largest group among the studied cases after metastases [Figure 4].
|Figure 4 A 75-year-old male patient complaining of chronic back pain. Diagnosis: multiple myeloma. Sagittal and left parasagittal T1-WI shows marrow infiltration of the vertebral bodies of L1 and L4 vertebrae by low signal intensity lesion. Axial T2-WI shows heterogenous high signal intensity marrow infiltration of the vertebral body of L1. WI, weighted image.|
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In our study, all cases of multiple myeloma involved the spine. The dorsal spine was the most common site of involvement, being involved in five of six cases (83.3%), followed by the lumbar spine, which was involved in four cases (66.6%), and the cervical spine, which was involved in only one case (16.6%). Our findings are in agreement with those of Kaiser and Ramos , and Rahmouni et al. , who reported that the spine is the most commonly involved site by multiple myeloma. Our findings are also in agreement with those of Huvos , who mentioned that in multiple myeloma the lower thoracic and lumbar spine involvement predominates. The flat bones of the pelvis, skull, ribs, clavicle, and scapula are also frequently involved. The diaphyses of the proximal long tubular bones (femur and humerus) are commonly affected.
Daffner et al.  mentioned that multiple myeloma has no characteristics that distinguish it from other bone marrow infiltrating processes on MRI. The usual appearance is nonspecific. Moulopoulos et al.  and Kaplan and Dussault  stated that multiple myeloma has a variable appearance by MRI and may show diffuse, focal, or inhomogenous variegated appearance. In our series, MRI revealed only two patterns of myelomatous involvement of the marrow: focal and variegated patterns. In our study, the focal pattern of myelomatous infiltration was the most common among the cases seen: four of six cases (66.6%). This is in agreement with the reports of Fruehwald et al. , Libshitz et al. , and Moulopoulos et al. . Moulopoulos and colleagues reported focal pattern in 45%, and diffuse and variegated patterns in 35 and 20% of patients in their study, respectively. Libshitz and colleagues detected diffuse marrow involvement in 48% of multiple myeloma cases. In our study, the variegated pattern was seen in two of six cases (33.3%). In our series, we did not find more than one pattern. This is in agreement with the reports of Moulopoulos et al. , who stated that they did not observe more than one pattern of marrow involvement in any of their multiple myeloma patients.
In our study, focal pattern of myelomatous involvement of the spine was considered if there was patchy involvement of bone marrow or if one or more vertebral bodies were diffusely involved by multiple myeloma provided that uninvolved marrow was present in other vertebral bodies. This is in agreement with the report of Moulopoulos et al. .
Regardless of the pattern of involvement, myeloma almost always has a SI that is equal to or lower than that of skeletal muscle or disc on T1-WI, which may be somewhat difficult to distinguish from normal red marrow. Occasionally, focal lesions will have high SI on TI-WI, presumably from hemorrhage into the lesion . On T2-WI, the myelomatous lesions demonstrate increased SI ,.
In our series, all multiple myeloma cases showed low SI on T1-WI (100%). On T2-WI, four of six cases showed high SI (66.6%) and two cases showed isointense to intermediate SI (33.3%). Postcontrast T1-WI imaging was performed in five patients, four of whom showed mild contrast, whereas the other patient showed moderate enhancement. This is in agreement with the results of Moulopoulos et al. .
In our series, the detection of myelomatous marrow infiltration was highly improved by using fat saturation techniques. These techniques were used in three of six cases in our series (50%). Also, the detection of myelomatous marrow infiltration was highly improved and showed enhancement on T1-WI after the administration of gadolinium. Postcontrast T1-WI imaging was performed in five cases, four of which showed mild contrast enhancement, whereas the other case showed moderate enhancement. This is in agreement with the results of Rahmouni et al. , Rahmouni et al. , and Volger and Murphy , who stated that multiple myeloma exhibits nonspecific changes on T1-WI and therefore can be difficult to distinguish from normal marrow. Detection of bone marrow myeloma is best achieved with STIR or T2-WI with fat suppression.
In multiple myeloma, compression fractures of the spine or pathological fractures of long bones, spinal cord compression, or a mixture of these findings may be present .
MRI can accurately detect spinal and/or nerve root compression and can assess soft tissue extension in cases of multiple myeloma. The findings of a large focal lesion in the spine with or without cord impingement may need local management. It may also help differentiate between osteoporotic and malignant vertebral compression fractures .
In our study, four of six cases had vertebral collapse (66.6%), two cases in the lumbar spine and two cases in the dorsal spine. All four cases had one vertebral collapse. This is in agreement with the results of Fruehwald et al. , and Mouopoulos et al. ,, who stated that vertebral compression fractures are often present at diagnosis or develop during the course of multiple myeloma. Our results are also in agreement with those of Lecouvet et al. , who reported that vertebral compression fractures are present in 50–70% of patients with multiple myeloma and it is the initial clinical sign in 34–64% of these patients. Amour et al. , Yochum and Rowe  detected compression fractures in 73 and 20% of their multiple myeloma cases, respectively.
Moulopoulos et al.  stated that, in cases of multiple myeloma, extraosseous mass from lesions in the spine can enter the spinal canal and compress the spinal cord. MR images of the spine can accurately assess the level and extent of cord compression.
Among the cases of multiple myeloma in our study, three of six cases showed intraspinal epidural mass (50%) and three cases showed paraspinal mass (50%). Thecal sac compression was seen in two of six cases (33.3%). Cord compression was seen in one of six cases (16.6%). Nerve root compression was seen in one case (16.6%). This is in agreement with the reports of Rahmouni et al. , who stated that epidural involvement is a well-known complication of multiple myeloma. Lecouvet et al.  reported that in multiple myeloma, spinal cord and root compression occurs in 10–20% of patients with 80% of neurologic symptoms at the thoracic level.
In our study, the first case showed involvement of the iliac bone, whereas the other case showed involvement of the spine. Major et al.  stated that plasmacytoma is commonly found in the axial skeleton. Yochum and Rowe  reported that the mandible, ilium, vertebrae, ribs, proximal femur, and scapula are the favored sites of involvement by plasmacytoma.
In our series, plasmacytoma lesions exhibited hypointense signal in T1-WI and hyperintense signal on T2-WI images. In postcontrast series, the first case showed intense contrast enhancement, whereas the second case showed mild contrast enhancement. Major et al.  reported that, on MRI, solitary plasmacytoma appears as an expansible lesion, which has low SI on TI-WI and high SI on T2-WI involving the entire vertebral body. The lesion has curvilinear low SI structures on all imaging sequences that extend partially through the vertebral body and resemble sulci seen in the brain, which is termed ‘mini brain’ appearance on axial images. In our series, neither of the two cases showed the mini-brain sign.In our study, the first case that involved the L3 vertebra showed vertebral collapse and an intraspinal mass with subsequent compression of the thecal sac. This is as seen in the study by Bredella et al. , who stated that plasmacytoma of the spine can destroy a vertebra and break through the cortex to produce a soft tissue mass and often leads to vertebral collapse. If the soft tissue component enters the epidural space, cord compression and myelopathy may result.
In our study, both cases of Ewing’s sarcoma showed involvement of the femur, being diaphyseal in the first case and metadiaphyseal in the other one. This is in agreement with the reports of Miller and Hoffer , who stated that ES occurs most frequently in the long tubular bones and flat bones (scapula) in the appendicular skeleton, and in the ribs and pelvis in the axial skeleton. Neoplasms of the long bones predominate in patients in the first two decades of life, whereas lesions of the flat bones are more prevalent in older patients. This is also in agreement with the results of Bredella et al. , who stated that Ewing’s sarcoma can affect any bone in the body; the femur, ilium, humerus, and tibia are the most common sites [Figure 5].
|Figure 5 Pain in the left upper thigh. Diagnosis: Ewing’s sarcoma. Coronal T2-WI: the upper half of the left femoral shaft is seen infilterated with high signal intensity with cortical invasion, lamellar periosteal reaction, and circumferential extraosseous soft tissue mass. WI, weighted image.|
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In our study, both cases of Ewing’s sarcoma showed hypointense signal on T1-WI and hyperintense signal on T2-WI, with mild contrast enhancement in the T1 postcontrast study. Both cases showed cortical invasion and extraosseous soft tissue. This is in agreement with the results of Bredella et al.  (4%), who stated that Ewing’s sarcoma demonstrates low SI on T1-weighted sequences and high SI on T2, fat-suppressed T2-weighted fast spin-echo, and STIR sequences. Marrow involvement and peritumoral edema are clearly delineated on fat-suppressed T2-weighted fast spin-echo images. There is usually a substantial soft-tissue component associated with Ewing’s sarcoma.
In our study, the dorsal spine was involved with focal pattern of altered marrow signal. It showed hypointense signal on T1-WI and isointense signal on T2-WI with intense contrast enhancement in the postcontrast series. Moore et al.  mentioned that MRI has proven to be very sensitive for depicting changes in the bone marrow in patients with leukemia.
| Conclusion|| |
This study confirms that MRI is a sensitive method for detection of areas of marrow infiltration. The value of MRI lies in its ability to document the presence and extent of disease and in determining an appropriate radiation field. MRI of the bone marrow can be used as a noninvasive imaging method to indicate prognosis and guide biopsy. Most of our results are in agreement with those of other researchers.
MRI can detect intramedullary infiltration in a highly advanced manner. It is also useful in the detection of tumor extension, associated soft tissue masses, and neurological compromise. MRI can increase the rate of successful bone marrow biopsies as it can assess a large volume of bone marrow noninvasively and relatively quickly and thus can detect foci of marrow involvement in diseases with a focal pattern of marrow infiltration.
Conflicts of interest
The authors declare no conflict of interest.
| References|| |
Moulopoulos LA, Dimopoulos MA. Magnetic resonance imaging of the bone marrow in hematologic malignancies. Blood 1997;90:2127–2147.
VolgerIII JB, Murphy WA. Diffuse marrow disease. In: Berquist TH, editor. MRI of the musculoskeletal system. 5th ed. Philadelphia, PA; Lippincott: Williams & Wilkins; 2006:979–1028.
Moore SG, Gooding CA, Brasch RC, Ehman RL, Ringertz HG, Ablin AR et al.
Bone marrow in children with acute lymphocytic leukemia: MR relaxation times. Radiology 1986;160(1):237–240.
Cohen MD, Klatte EC, Baehner R, Smith JA, Martin-Simmerman P, Carr BE et al.
Magnetic resonance imaging of bone marrow disease in children. Radiology 1984;151(3):715–718.
Daffner RH, Lupetin AR, Dash N, Deeb ZL, Sefczek RJ, Schapiro RL. MRI in the detection of malignant infiltration of bone marrow. Am J Roentgenol 1986;146(2):353–358.
Boyko OB, Cory DA, Cohen MD, Provisor A, Mirkin D, DeRosa GP. MR imaging of osteogenic and Ewing’s sarcoma. Am J Roentgenol 1987;148(2):317–322.
Steiner RM, Mitchell DG, Rao VM, Schweitzer ME. Magnetic resonance imaging of diffuse bone marrow disease. Radiol Clin North Am 1993;31(2):383–409.
Bohndorf K. Bone lesions of the spine. MR: state of the art, Categorical Course ACR 1991;91:217–223.
Vanel D, Dromain C, Tardivon A. MRI of bone marrow disorders. Eur Radiol 2000;10:224–229.
Yochum TR, Rowe LJ. Tumors and tumor-like processes. In: xx xx. Essentials of skeletal radiology. 2nd ed. Baltimore; London; Los Angeles; Sydney: Lippincott Williams and Wilkins; 1996:975.
Amour TE, St Hodges SC, Laakman RW et al.
MRI of the spine. New York, NY: Raven Press Ltd; 1994:455.
Gold RI, Seeger LL, Bassett LW, Steckel RJ. An integrated approach to the evaluation of metastatic bone disease. Radiol Clin North Am 1990;28(2):471–483.
Byrne TN, Waxman SG. Spinal cord compression: diagnosis and principles of management. Philadelphia, PA: FA Davis; 1996 146.
Asdourian PL. Metastaic disease of the spine. In: Bridwell KH, DeWald RL, eds The textbook of spinal surgery. Philadelphia, PA: JB Lippincott; 1991:1187.
Algra PR, Heimans JJ, Valk J, Nauta JJ, Lachniet M, van Kooten B. Do metastases in vertebrae begin in the body or in the pedicles? Imaging study in 45 patients. Am J Roentgenol 1992;158(6):1275–1279.
Algra PR, Bloem JL, Tissing H, Falke TH, Arndt JW, Verboom LJ Detection of vertebral metastases: comparison between MR imaging and bone scintigraphy. Radiographics 1991;11(2):219–232.
Greenfield GB, Arrington JA. Imaging of bone tumors. A multimodality approach. 1st ed. Philadelphia, PA: J.B. Lippincott Company; 1996:43.
Enzmann DR, Delapaz RL. Tumor. In Enzmann DR, Delapaz RL, Rubin JB, eds, Magnetic resonance of the spine. 1st ed. St Louis; Baltimore; Philadelphia; Toronto: The C.V. Mosby Company; 1990:301.
Frank JA, Ling A, Patronas NJ, Carrasquillo JA, Horvath K, Hickey AM, Dwyer AJ Detection of malignant bone tumors: MR imaging vs scintigraphy. Am J Roentgenol 1990;155(5):1043–1048.
Traill Z, Richards MA, Moore NR. Magnetic resonance imaging of metastatic bone disease. Clin Orthop and Relat Res 1995;312:76–88.
Kostuik JP, Weinstein JN. Differential diagnosis and surgical treatment of metastatic spine tumors. In: Frymoyer, JW, ed. The adult spine: principles and practice. New York, NY: Raven Press; 1991:861.
Devita VI, Hellman S, Jaffe ES et al.
Hodgkin’s disease and lymphomas. In: xx xx. Cancer − principles in practice of oncology. 4th ed. Philadelphia, PA: JB Lippincott; 1993:1819.
Mac Vicar D, Husband JE. Reticuloendothelial disorders. In: xx xx Grainger and Allison’s diagnostic radiology. Textbook of medical imaging. 3rd ed New York; Edinburgh; London; Madrid; Melbourne; San Francisco; Tokyo: Churchill Livingstone; 1997:2555.
Linden A, Zankovich R, Theissen P, Diehl V, Schicha H. Malignant lymphoma: bone marrow imaging versus biopsy. Radiology 1989;173(2):335–339.
Edeiken-Monroe B, Edeiken J, Kim EE. Radiologic concepts of lymphoma of bone. Radiol Clin North Am 1990;28(4):841–864.
Hoane BR, Shields AF, Porter BA, Shulman HM. Detection of lymphomatous bone marrow involvement with magnetic resonance imaging. Blood 1991;78:728–738.
Kaiser MC, Ramos L. Tumors. In: xx xx. MRI of the spine. A guide to clinical applications. 1st ed. New York, NY: Thieme Medical Publishers Inc.; 1990:60.
Rahmouni A, Divine M, Mathieu D, Golli M, Dao TH, Jazaerli N et al.
Detection of multiple myeloma involving the spine: efficacy of fat-suppression and contrast-enhanced MR imaging. Am J Roentgenol 1993a;160(5):1049–1052.
Huvos AG. Bone tumors: diagnosis, treatment and prognosis. 2nd ed. Philadelphia, PA: WB Saunders; 1991:653–676.
Moulopoulos LA, Varma DG, Dimopoulos MA, Leeds NE, Kim EE, Johnston DA et al.
Multiple myeloma: spinal MR imaging in patients with untreated newly diagnosed disease. Radiology 1992;185(3):833–840.
Kaplan PA, Dussault RG. Bone marrow. In Higgins CB, Hricak H, Helms CA, eds. Magnetic resonance imaging of the body. Philadelphia; New York: Lippincott-Raven Publishers; 1997:1295.
Fruehwald FX, Tscholakoff D, Schwaighofer B, Wicke L, Neuhold A, Ludwig H, Hajek PC. Magnetic resonance imaging of the lower vertebral column in patients with multiple myeloma. Invest Radiol 1988;23(3):193–199.
Libshitz HI, Malthouse SR, Cunningham D, MacVicar AD, Husband JE. Multiple myeloma: appearance at MR imaging. Radiology 1992;182 (3):833–837.
Rahmouni A, Divine M, Mathieu D, Golli M, Haioun C, Dao TH et al.
MR appearance of multiple myeloma of the spine before and after treatment. Am J Roentgenol 1993b;160(5):1053–1057.
Salmon SE, Cassady JR. Plasma cell neoplasms. In Devita VT, Hellman S, Rosenberg SA, eds. Cancer principle and practice of oncology. 5th ed. Philadelphia; New York: Lippincott-Raven Publishers; 1997:2344.
Moulopoulos LA, Gika D, Anagnostopoulos A, Delasalle K, Weber D, Alexanian R, Dimopoulos MA. Prognostic significance of magnetic resonance imaging of bone marrow in previously untreated patients with multiple myeloma. Ann Oncol 2005;16(11):1824–1828.
Moulopoulos LA, Dimopoulos MA, Smith TL, Weber DM, Delasalle KB, Libshitz HI, Alexanian R. Prognostic significance of magnetic resonance imaging in patients with asymptomatic multiple myeloma. Clin Oncol 1995;13:251–256.
Lecouvet FE, Malghem J, Michaux L, Michaux JL, Lehmann F, Maldague BE et al.
Vertebral compression fractures in multiple myeloma. Part II. Assessment of fracture risk with MR imaging of spinal bone marrow. Radiology 1997;204(1):201–205.
Lecouvet FE, Vande Berg BC, Michaux L, Scheiff JM, Malghem J, Jamart J et al.
Chronic lymphocytic leukemia: changes in bone marrow composition and distribution assessed with quantitative MRI. J Magn Reson Imaging 1998;8(3):733–739.
Major NM, Helms CA, Richardson WJ. The ‘mini brain’: plasmacytoma in a vertebral body on MR imaging. Am J Roentgenol 2000;175(1):261–263.
Bredella MA, Steinbach L, Caputo G, Segall G, Hawkins R. Value of FDG PET in the assessment of patients with multiple myeloma. Am J Roentgenol 2005;184(4):1199–1204.
Miller AL , Hoffer FA. Malignant and benign bone tumors. Radiol Clin North Am 2001;39(4):673–699.
[Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5]
[Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6], [Table 7], [Table 8], [Table 9], [Table 10], [Table 11], [Table 12], [Table 13]