Value of whole-body turbo short tau inversion recovery magnetic resonance imaging with panoramic table for detecting bone metastases: comparison with 99MTc-methylene diphosphonate scintigraphy

OBJECTIVE: The objectives of this study were to assess the efficacy and reliability of whole-body turbo short tau inversion recovery (STIR) magnetic resonance imaging (MRI) for detecting skeletal metastasis and to compare the results with those of bone scintigraphy. METHODS: Twenty-six patients with primary cancer (mean age=56 years, age range: 34-75 years) were assessed for bone metastasis with whole-body MRI and bone scintigraphy. Eight bone regions in each patient were assessed (total of 208 sites) with each of these 2 techniques. A turbo STIR sequence and panoramic table were used during MRI. Whole-body MRI and scintigraphy findings were compared with biopsy or follow-up imaging results. RESULTS: After at least 12 months of follow-up, 9 patients had bone metastases in a total of 31 sites. Whole-body MRI showed 29 metastases (94%) in the total 208 skeletal sites investigated in the 26 patients. Bone scintigraphy revealed metastases in 16 (52%) of the 208 sites. CONCLUSION: Whole-body turbo STIR MRI is a reliable method for screening patients with suspected skeletal metastases. This technique is also advantageous in that it reveals extraskeletal organ and soft tissue metastases.     

Whole-body MRI using a rolling table platform for the detection of bone metastases

The aim of this study was to compare the results of whole-body MRI using a recently developed rolling table platform with findings of nuclear scintigraphy in patients with bone metastases. Twenty-six patients with known or suspected bone metastases who had undergone radionuclide scintigraphy were examined by MRI. Patients were placed on a rolling table platform with integrated phased-array surface coils [BodySURF (system for unlimited field of view)] capable of pulling the patient through the isocenter of the magnet. Using a five-station approach three different image sets (T1-weighted gradient recalled echo, half-Fourier acquired single-shot turbo spin echo, and short tau inversion recovery) were collected in the coronal plane. In addition, the spine was imaged in the sagittal plane. The MRI findings were compared with the results obtained by scintigraphy. The whole-body MR examination lasting merely 40 min was feasible in all 26 patients. The MRI revealed excellent correlation with scintigraphy regarding metastatic lesions. A total of 60 regions with metastatic lesions were identified on bone scintigraphy. Fifty-three regions were detected on identical locations by MRI. The regions missed by MRI were located mainly in ribs and skull. The MRI could identify additional bone metastases in spine, pelvis, and femur. The MRI screening for bone metastases correlated well with bone scintigraphy. Use of the rolling table platform permits rapid imaging based on three different contrast mechanisms of the entire skeletal system.     

Whole-body bone marrow MRI in patients with metastatic disease to the skeletal system

PURPOSE: The purpose of this study was to evaluate the diagnostic potential of a whole-body bone marrow MR protocol in the detection of bone metastases. METHOD: Whole-body bone marrow MRI was performed in 18 patients with known malignant tumors and suspected bone metastases. The imaging protocol consisted of fast T1-weighted and STIR sequences applied in different anatomical positions covering the whole skeleton. MRI findings indicating bone metastases were compared with findings from bone scintigraphy. Metastatic lesions were confirmed by follow-up MR examinations, bone scintigraphy, radiography, or CT. RESULTS: A total number of 216 lesions were detected with MRI in comparison with 159 lesions detected with bone scintigraphy. Follow-up examinations confirmed 105 lesions. MRI detected 96 (91.4%) of the confirmed lesions, whereas bone scintigraphy detected 89 (84.8%). The entire examination, including patient positioning and changing of imaging coils, required 45 min of room time. CONCLUSION: Whole-body bone marrow MRI as used in this study is an effective method for evaluating the entire skeletal system in patients with suspected metastatic disease.     

Early response of breast cancer bone metastases to chemotherapy evaluated with MR imaging

Purpose: To compare T1-weighted spin-echo and fat-suppressed long echo time inversion recovery turbo spin-echo (long TE IR-TSE) MR images in the evaluation of early response of breast cancer bone metastases to chemotherapy.Material and Methods: Eighteen breast cancer patients with known bone metastases were investigated prospectively by MR, using T1-weighted and long TE IR-TSE sequences on the sternum, spine, pelvis and proximal femora, before and after a median of 6 courses of chemotherapy. Therapeutic response evaluation with MR was based on change in tumor size assessed quantitatively by measuring all focal metastases, and change in pattern and signal intensity (SI) of the metastases, assessed visually. Combined response evaluation based on clinical findings, conventional radiography, and scintigraphy was used as reference.Results: Progressive disease (2 patients) and no change (4 patients) were assessed equally well on both MR sequences. Long TE IR-TSE demonstrated partial response with higher accuracy than T1-weighted images, 58% (7/12 patients) vs. 17% (2/12 patients). In patients without progression there was an SI increase in or around the metastases in 6 patients on T1-weighted images and in 7 patients on long TE IR-TSE images.Conclusion: The long TE IR-TSE sequence demonstrated early partial response of breast cancer bone metastases to chemotherapy more accurately than the T1-weighted sequence.     

Turbo STIR magnetic resonance imaging as a whole-body screening tool for metastases in patients with breast carcinoma: preliminary clinical experience

This study was undertaken to assess the utility of whole-body turbo short tau inversion recovery (STIR) magnetic resonance imaging (MRI) to detect metastases to liver, brain, and bone as a single examination in women with breast cancer. Seventeen patients with biopsy-proven breast cancer and suspected metastatic disease attending over a 12-month period referred for both conventional imaging and whole-body MRI were included in the study. Three patients were found to be free of metastases at both conventional and MR imaging. Appendicular or axial skeletal metastases were identified in 11 of 17 patients, with correlation between findings at whole-body MRI and scintigraphy in 15 of the 17 patients. Five patients had evidence of hepatic metastases on whole-body MRI, of which metastases were identified in only three patients at CT despite contrast enhancement. Four patients had brain abnormalities (metastases in three patients, meningioma in one patient) detected on both whole-body and dedicated brain MRI. Preliminary clinical experience suggests that turbo STIR whole-body MRI may represent a convenient and cost-effective method of total body screening for metastases in patients with breast carcinoma.     

Role of whole-body diffusion-weighted MRI in detecting bone metastasis

Purpose

The aim of this study was to compare the results of whole-body diffusion-weighted magnetic resonance (DW-MR) imaging with staging based on computed tomography (CT) and nuclear scintigraphy using Tc99m results as the standard of reference.

Methods and materials

Seventeen patients with known malignant tumours were included in the study. The thorax and the abdomen were imaged using breath-hold diffusion-weighted imaging and T1-weighted imaging sequences in the coronal plane. Location and size of osseous metastases were documented by two experienced radiologists. Whole-body DW-MR imaging findings were compared with results obtained at skeletal scintigraphy and CT bone survey.

Results

The mean examination time for whole-body DW-MR imaging was 25.5 min. All bone metastases regardless of the size were identified with whole-body DW-MR imaging; MR imaging depicted more bone metastases than CT. Skeletal scintigraphy depicted osseous metastases in 13 patients (with greater sensitivity to the lower limb), whereas whole-body DW-MR imaging revealed osseous metastases in 13 patients (with greater sensitivity to the spine). DW-MR did not show good results for detection of rib cage metastases. The additional osseous metastases seen with MR imaging were confirmed at follow-up examinations and some had a change in therapy. MR identified 22 % more metastatic lesions when compared to bone scintigraphy and 119 % when compared to CT. Bone scintigraphy identified 80 % more metastatic lesions when compared to CT. On a per-patient basis, whole-body DW-MR imaging revealed sensitivity and specificity values of 100 %.

Conclusion

Whole-body DW-MR imaging was more sensitive in the detection of osseous metastases than were skeletal scintigraphy and CT bone survey.     

Whole-body MR imaging of bone marrow

In clinical routine, multimodality algorithms, including X-ray, computed tomography, scintigraphy and MRI, are used in case of suspected bone marrow malignancy. Skeletal scintigraphy is widely used to asses metastatic disease to the bone, CT is the technique of choice to assess criteria of osseous destruction and bone stability. MRI is the only imaging technique that allows direct visualization of bone marrow and its components with high spatial resolution. The combination of unenhanced T1-weighted-spin echo- and turbo-STIR-sequences have shown to be most useful for the detection of bone marrow abnormalities and are able to discriminate benign from malignant bone marrow changes. Originally, whole-body MRI bone marrow screening was performed in sequential scanning techniques of five body levels with time consuming coil rearrangement and repositioning of the patient. The introduction of a rolling platform mounted on top of a conventional MRI examination table facilitated whole-body MR imaging and, with the use of fast gradient echo, T1-weighted and STIR-imaging techniques, for the first time allowed whole-body imaging within less than one hour. With the development of parallel imaging techniques (PAT) in combination with global matrix coil concepts, acquisition time could be reduced substantially without compromises in spatial resolution, enabling the implementation of more complex and flexible examination protocols. Whole-body MRI represents a new alternative to the stepwise multimodality concept for the detection of metastatic disease, multiple myeloma and lymphoma of the bone with high diagnostic accuracy.     

Whole-body MR imaging: evaluation of patients for metastases

PURPOSE: To compare the results of whole-body magnetic resonance (MR) imaging with staging based on computed tomographic (CT), dedicated MR imaging, and nuclear scintigraphic results as standard of reference. MATERIALS AND METHODS: Fifty-one patients with known malignant tumors were included in the study. Patients were placed on a rolling table platform capable of moving the patient rapidly through the isocenter of the magnet bore. The thorax and the abdomen were imaged by using fast breath-hold T2-weighted sequences in the transverse plane. After intravenous administration of a paramagnetic contrast agent, three-dimensional gradient-echo data sets were collected in five stations and covered the body from the skull to the knees. Location and size of cerebral, pulmonary, hepatic, and osseous metastases were documented by two experienced radiologists. Whole-body MR imaging findings were compared with results obtained at skeletal scintigraphy, CT, and dedicated MR imaging. RESULTS: The mean examination time for whole-body MR imaging was 14.5 minutes. All cerebral, pulmonary, and hepatic metastases greater than 6 mm in diameter could be identified with whole-body MR imaging. Small pulmonary metastases were missed with MR imaging, which did not change therapeutic strategies, but MR imaging depicted a single hepatic metastasis that was missed with CT. Skeletal scintigraphy depicted osseous metastases in 21 patients, whereas whole-body MR imaging revealed osseous metastases in 24 patients. The additional osseous metastases seen with MR imaging were confirmed at follow-up examinations but did not result in a change in therapy. Whole-body MR imaging performed on a per-patient basis revealed sensitivity and specificity values of 100%. CONCLUSION: Whole-body MR imaging for the evaluation of metastases compared well with the reference techniques for cerebral, pulmonary, and hepatic lesions. Whole-body MR imaging was more sensitive in the detection of hepatic and osseous metastases than were the reference techniques.     

Screening for skeletal metastases of the spine and pelvis: gradient echo opposed-phase MRIcompared with bone scintigraphy

Opposed-phase gradient eho (GRE) MRI at 0.5 T was compared with T1-weighted GRE MRI and bone scintigraphy regarding the detection of malignant bone marrow infiltrates of the spine and pelvis. Seventeen control patients and 41 patients with suspected skeletal metastases were studied with plain and gadolinium-enhanced MRI. In the control group only a vertebral haemangiona showed contrast enhancement, while all metastases (confirmed histologically or by follw-up) were enhancing. Opposed-phase surface coil MRI showed a significantly higher contrast-to-noise ratio of 56 metastases than T1-weighted images. In 28 patients body coil opposed-phased MRI detectedmore metastatic foci of the spine and pelvis than did bone scintigraphy (84 vs 56). No scintigraphically visualised lesion was missed by MRI. In conclusion,body coil gadolinium-enhanced opposed-phase GRE MRI may be applied as a screning method for skeletal metastases of the spine and pelvis at intermediate field strengths. Correspondence to: K. Neumann     

How does iliac crest bone marrow biopsy compare with imaging in the detection of bone metastases in small cell lung cancer?

Iliac crest bone marrow biopsy (BMB) has often been used as the gold standard for the detection of bone marrow metastases in small cell lung cancer (SCLC). However, it is likely to lead to numerous false-negative results. For this reason, we compared the results of bone scintigraphy (BS), magnetic resonance imaging (MRI), and BMB in 48 sequential patients affected with pathologically confirmed SCLC (47 were evaluable; mean age, 58.4 years). The three procedures were carried out within 1 week, no treatment being performed during this period. Whole-body scans and spot views were obtained in the anterior and posterior projections. For MRI, only the thoracolumbar spine, the sternum and the pelvis were scanned, using spin-echo T1-weighted sequences, resulting in an acquisition time of less than 45 min. Only five BMBs were rated as positive. In these cases, both BS and MRI were also positive. The other 42 biopsies were negative. Among them, in ten cases both BS and MRI were positive. In 21 cases, both BS and MRI were negative. In five cases MRI was positive while BS was negative. Finally, in six cases MRI was negative whilst BS was positive. In most cases in which either BS or MRI was positive, follow-up scans confirmed the initial findings. This study suggests that BMB is more invasive and less sensitive than BS or MRI in detecting bone metastases. MRI seems to be more sensitive than BS in detecting small spinal or pelvic metastases. Whole-body bone scintigraphy is more sensitive in detecting skull, costal or peripheral metastases. BS and MRI should be used in combination and may replace BMB in the detection of bone metastases in SCLC. Correspondence to: I. Perrin-Resche     

Whole-body iodine-131 metaiodobenzylguanidine imaging for detection of bone metastases in patients with paraganglioma: comparison with bone scintigraphy

Iodine-131 metaiodobenzylguanidine (¹³¹I-MIBG) therapy is an effective treatment for patients with malignant paraganglioma for which surgical resection is not indicated. We performed high-dose ¹³¹I-MIBG therapy on two patients with malignant paraganglioma and multiple bone metastases. The bone metastases were diagnosed by magnetic resonance imaging (MRI). Metastatic bone lesions were evaluated by whole-body ¹³¹I-MIBG imaging and bone scintigraphy. Whole-body ¹³¹I-MIBG imaging showed extensive metastatic bone lesions, whereas conventional bone scintigraphy did not. There was a remarkable discrepancy between ¹³¹I-MIBG imaging and bone scintigraphy in the diagnosis of metastatic bone lesions of malignant paraganglioma in our two patients. High-dose ¹³¹I-MIBG imaging may detect early stages of bone metastases, compared with bone scintigraphy, in patients with malignant paraganglioma.     

Comparison of whole-body STIR-MRI and <Superscript>99m</Superscript>Tc-methylene-diphosphonate scintigraphy in children with suspected multifocal bone lesions

The study was performed to compare whole-body short time inversion recovery (STIR) MR imaging and ^99mTc-methylene diphosphonate planar scintigraphy in the examination of children with suspected multifocal skeletal malignant lesions. Sixteen patients with known or suspected malignant skeletal disease underwent both whole-body STIR MR imaging and bone scintigraphy. The lesions were described and numbered according to scintigraphic evaluation criteria. Thus, 16 regions were analyzed in each patient for the comparison between the two modalities. Histology was proven in the primary malignant regions. Follow-up MRIs were registered. Scintigraphy and MRI follow-up were evaluated as gold standard. A total of 139 different lesions was observed by both modalities. Baseline whole-body MRI revealed 119 bone lesions in 256 possible sites (46.5%); scintigraphy revealed only 58 lesions (22.6%). Congruence was observed in only four patients (25%). According to the location of the lesion, correlation was observed in 39/139 lesions (28%). In all, 57.5% of the lesions were detected only by MRI and 14.5% of the lesions were detected only by scintigraphy. Whole-body MRI was more sensitive (P<0.001). Of all lesions numbered which could be separated in the initial MRI, whole-body MRI detected 178 lesions in the patients. The results suggest that whole-body MRI using a STIR sequence is an effective radiation free method for examination of children with suspected multifocal bone lesions. MRI showed more lesions than conventional ^99mTc-methylene diphosphonate scintigraphy. Therefore, whole-body MRI may be feasible as a screening modality for metastatic and skip lesions in osteosarcoma, PNET, Ewing sarcoma and Langerhans cell histiocytosis in children.     

Comparative detectability of bone metastases and impact on therapy of magnetic resonance imaging and bone scintigraphy in patients with breast cancer.

OBJECTIVE: to evaluate the comparative impact of magnetic resonance imaging and bone scintigraphy in bone metastases of breast cancer. METHODS AND PATIENTS: in 81 patients with histologically proven breast cancer magnetic resonance imaging of the axial skeleton and whole-body bone scintigraphy had been performed. Images were retrospectively reviewed and compared for detection of metastases, extent of metastatic disease and therapeutic implications according to the patients' records. RESULTS: about 54/81 (67%) patients revealed bone metastases. In 7/54 (13%) patients with bone metastases, scintigraphy was false negative. In one patient a solitary sternal metastases was seen. In 26/53 [49%] patients with spinal metastases, magnetic resonance imaging showed more extensive disease. Local radiotherapy or surgery was indicated in ten patients with metastases not evident in bone scintigraphy, in 20 patients with positive results by both imaging modalities and in six patients with metastases of pelvis imaged by bone scintigraphy only. CONCLUSION: magnetic resonance imaging of the axial skeleton and pelvis appears superior for staging as only one patient had metastases merely outside the axial skeleton and local therapy was indicated even in spinal regions negative in bone scintigraphy.     

Comparison of18FDG-PET with99mTc-HMDP scntigraphy for the detection of bone metastases in patients with breast cancer

OBJECTIVE: Bone is one of the most common sites of metastasis in breast cancer patients. Although bone scintigraphy is widely used to detect metastatic breast cancer, the usefulness of 18FDG-PET for detecting bone metastasis has not been clearly evaluated. The purpose of this study was to compare the diagnostic accuracy of 18FDG-PET with bone scintigraphy in detecting bone metastasis in breast cancer patients. METHODS: Forty-four women aged 35 to 81 years (mean, 56 years) with breast cancer were examined in this study. Both 18FDG-PET and bone scintigraphy were performed for each patient with 0-69 day intervals (mean, 11.5 days). The results of each image interpretation were compared retrospectively. Whole-body bones were classified into 9 anatomical regions. Metastases were confirmed at 45/187 regions in 14 patients by bone biopsy or clinical follow-up including other imaging techniques for a period of at least 6 months afterwards. RESULTS: On a region basis, the sensitivity, specificity, and accuracy of 18FDG-PET were 84%, 99% and 95%, respectively. Although these results were comparable to those of bone scintigraphy, the combination of 18FDG-PET and bone scintigraphy improved the sensitivity (98%) and accuracy (97%) of detection. False negative lesions of bone scintigraphy were mostly bone marrow metastases and those of 18FDG-PET were mostly osteoblastic metastases. 18FDG-PET was superior to bone scintigraphy in the detection of osteolytic lesions (92% vs. 73%), but inferior in the detection of osteoblastic lesions (74% vs. 95%). CONCLUSIONS: This study shows that 18FDG-PET tends to be superior to bone scintigraphy in the detection of osteolytic lesions, but inferior in the detection of osteoblastic lesions. 18FDG-PET should play a complementary role in detecting bone metastasis with bone scintigraphy.     

MRI and PET/CT of patients with bone metastases from breast carcinoma

3.0Tesla magnetic resonance imaging (MRI) with diffusion-weighted imaging (DWI) was compared with combined 18F-fluorodeoxyglucose positron emission tomography and computed tomography (PET/CT) in patients with suspected bone metastases from breast cancer. A prospective clinical study was performed in 13 female breast cancer patients (mean age 61years; range 45-85 years). The spine was imaged in the sagittal plane with T1-weighted (T1), short tau inversion recovery (STIR), and T2-weighted fat-saturated (T2) sequences. The pelvis was imaged similarly in the coronal plane. Axial DWI was performed from the skull base to the mid-thigh. MRI and PET/CT were performed in all patients at a maximum interval of 10 working days and at least 14 days after chemotherapy. MRI was reviewed by two radiologists, and their consensus on potential metastases in 27 predefined locations was recorded. The predefined locations were the vertebral bodies (24), the left (1) and right (1) pelvic bones, and the sacral bone (1). The PET/CT was reviewed by a radiologists and a nuclear medicine physician. MRI detected 59 of the 60 active metastases found with our gold standard modality PET/CT. T1 had the highest sensitivity (98%) but rather low specificity (77%), but with the addition of STIR and DWI, the specificity increased to 95%. The additional metastases detected with MRI most likely represented postherapeutic residual scars without active tumour. In conclusion, 3.0Tesla MRI with T1, STIR, and DWI is useful for the clinical evaluation of bone metastases from breast cancer and compares well to PET/CT.     

Whole-body MR imaging for detection of bone metastases in children and young adults: comparison with skeletal scintigraphy and FDG PET.

OBJECTIVE: The purpose of this study was to compare the diagnostic accuracy of whole-body MR imaging, skeletal scintigraphy, and 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) for the detection of bone metastases in children. SUBJECTS AND METHODS: Thirty-nine children and young adults who were 2--19 years old and who had Ewing's sarcoma, osteosarcoma, lymphoma, rhabdomyosarcoma, melanoma, and Langerhans' cell histiocytosis underwent whole-body spin-echo MR imaging, skeletal scintigraphy, and FDG PET for the initial staging of bone marrow metastases. The number and location of bone and bone marrow lesions diagnosed with each imaging modality were correlated with biopsy and clinical follow-up as the standard of reference. RESULTS: Twenty-one patients exhibited 51 bone metastases. Sensitivities for the detection of bone metastases were 90% for FDG PET, 82% for whole-body MR imaging, and 71% for skeletal scintigraphy; these data were significantly different (p < 0.05). False-negative lesions were different for the three imaging modalities, mainly depending on lesion location. Most false-positive lesions were diagnosed using FDG PET. CONCLUSION: Whole-body MR imaging has a higher sensitivity than skeletal scintigraphy for the detection of bone marrow metastases but a lower sensitivity than FDG PET.     

Whole body MRI for detecting metastatic bone tumor: comparison with bone scintigrams.

PURPOSE: To compare the effectiveness of whole body MRI (WB-MRI [magnetic resonance imaging]) and bone scintigram (BS) at detecting bone metastasis. MATERIALS AND METHODS: WB-MRI was performed on 16 patients for detecting bone metastasis (6 breast carcinoma, 7 prostatic carcinoma, 1 renal cell carcinoma [RCC], 1 hepatocellular carcinoma [HCC], and 1 primary unknown). BS was also performed in all cases. Patients were placed on a table top extender (Philips Medical Systems). The maximal longitudinal field of view (FOV) was 200 cm. At first, the total spine was imaged in the sagittal plane with a three-station approach for two image sets (fast spin-echo [SE] T1-weighted images [T1WI] and short tau inversion recovery [STIR] images). The whole body was then imaged in the coronal plane with a seven-station approach for two image sets (fast field echo [FFE] T1WI and STIR). Total examination time, including patient positioning, was within 40 min. Three independent radiologists interpreted the imaging data. RESULTS: WB-MRI identified 5 cases of 24 lesions as bone metastasis, while BS identified 3 cases of 25 lesions. Concordance between WB-MRI and BS was seen in 3 cases of 22 lesions (81%). For two cases of 2 lesions, which were identified only with WB-MRI, the lesions were located in the sacrum and thoracic spine. For one case of 3 lesions, which was identified only with BS, the lesions were located in the skull and rib. CONCLUSION: WB-MRI was an excellent method for screening bone metastasis, especially the vertebral body.     

全身MRI与核素骨扫描对骨转移瘤诊断价值的对照研究

目的 评价全身MRI对骨转移瘤的诊断价值.方法 对30例经病理证实的恶性肿瘤患者在2周内分别进行伞身MRI及核素骨显像(BS),采取临床资料同常规MRI、CT等多种影像资料结合分析,辅以必要的随访复查为"金标准",分别以30例患者和270个部位为单位进行分析.使用McNemar检验比较两者对骨转移瘤诊断的敏感度、特异度.结果 30例患者中,"金标准"诊断27例患者存在骨转移,全身MRI检出25例,2例假阴性,无假阳性患者;BS检出27例阳性患者,其中2例为假阳性.以病例为单位,两者的敏感度均为92.6%(25/27),特异度分别为100%(3/3)及33.3%(1/3).ROC曲线下面积分别为0.9630及0.6296,差异无统计学意义(P>0.05).以病灶部位为单位统计显示全身MRI的敏感度、特异度分别为90.8%(108/119)、98.0%(148/151),高于骨扫描的70.6%(84/119)、90.7%(137/151)(P值均<0.01).全身MRI的ROC曲线下面积为0.9438,大于BS的0.8066(P<0.01).全身MRI同时发现3例患者存在脑转移,4例患者存在肺转移,4例患者存在肝转移.结论 全身MRI对骨转移瘤的综合诊断能力较Bs好,具有一定的临床应用价值.

Abstract：

Objective The aim of the study was to evaluate the reliability of whole-body MRI(WBMRI)in detecting osseous metastases.Methods Thirty patients verified with malignant tumor by histology were enrolled.All the patients underwent WB-MRI and bone scintigraphy(BS)with a two week interval.Clinical information,conventional MRI and CT images,and follow-up data were collected as gold standard for the diagnosis of bone metastases.The data of 30 patients and 270 segments as study unit respectively were analyzed.The sensitivity and specificity between WB-MRI and BS were compared with McNemar test.Resuits Bone metastases were confirmed in 27 of 30 patients by gold standard.Twenty-five patients with bone metastases were detected by WB-MRI and no false-positive cases.Twenty-seven patients with bone metastases were Nund by BS but having two false-positive oases.With patients as study unit,the diagnostic sensitivity of WB-MRI and BS were both 92.6%(25/27)and the specificity were 100%(3/3)and 33.3%(1/3),respectively.The area under ROC curve of WB-MRI and BS were 0.9630 and 0.6296,respectively(P>0.05).With segments as study unit,119 bone metastases segments were confirmed.The diagnostic sensitivity of WB-MRI and BS were 90.8%(108/119)and 70.6%(84/119)(P<0.01),while the specificity were 98.0%(148/151)and 90.7%(137/151),respectively(P<0.01).The area under ROC curve of WB-MRI and BS were 0.9438 and 0.8066.The former was obviously higher than the latter(P<0.01).Meauwhile.by WB-MRI,3 cases coexisting with brain metastases,4 cases with lung metastases,and 4 cases with hepatic metastases were found.Conclusion WB-MRI was a good tool for screening osseous metastases.     

Detection of malignant bone tumors: MR imaging vs scintigraphy

One hundred six patients with a known or suspected diagnosis of bone cancer (11 patients with biopsy-proved primary tumors, 95 patients with metastatic disease) were evaluated with scintigraphy and MR imaging to determine the relative sensitivity of each technique in the detection of bone disease. MR imaging was performed at 0.5 T as part of the entry evaluation into Intramural Research Board protocols (30%), for evaluation of cord compression, or because of an equivocal scintigram. MR was performed with T1-weighted (e.g., 300-500/10-20 [TR/TE]), T2-weighted (e.g., 2000/80) spin-echo (SE), and a short-TI inversion recovery (STIR) pulse sequence. Scintigrams were performed with 99mTc-methylene diphosphonate. A retrospective analysis showed that in 30 (28%) of 106 patients, MR imaging performed over a limited region of interest revealed a focal abnormality consistent with tumor that was not observed on scintigraphy. Only one patient had an abnormality on scintigraphy, caused by a metastasis, that was not found on MR images. In 73 (69%) of the 106 patients, the results of MR imaging and scintigraphy were equivalent; in 41 cases results of both techniques were normal. A McNemar analysis of the discordant cases showed MR imaging to be more sensitive than scintigraphy was (p less than .001). Our results suggest that although MR imaging has a greater sensitivity in detecting focal disease, scintigraphy is still the most useful screening test for evaluating the entire skeleton. MR imaging should be reserved for clarification of scintigraphic findings when suspicion is high for tumor.     

The value of bone scintigraphy,bone marrow scintigraphy and fast spin-echo magnetic resonance imaging in staging of patients with malignant solid tumours: a prospective study

The purpose of this prospective study was to define the value of bone scintigraphy (BS), bone marrow scintigraphy (BMS) and the new fast spin-echo (FSE) magnetic resonance imaging (MRI) sequences in screening for bone metastases in patients with solid malignant tumours. It was our particular interest to classify patients into a group with and a group without bone metastases, and not only to compare the absolute number of metastases detected by each method. Thirty-two patients were examined using technetium-99m dicarboxy propane diphosphonate bone scintigraphy, ^99mTc-labelled monoclonal anti-granulocyte antibodies for bone marrow scintigraphy and 1.5 T MRI using T1-weighted and FSE T2-weighted sequences. Against a reference standard obtained by re-evaluation of all clinical and imaging data 1 year after prospective BS, BMS and MRI had been performed, the three imaging modalities were falsely positive in two, eight and two cases and falsely negative in zero and four cases, respectively. BMS was falsely positive in eight patients because of vertebral marrow degeneration which caused photopenic defects which could not be differentiated from metastases. MRI showed these lesions to unequivocally contain fat. BMS and MRI were falsely negative in four cases because of the limited field of examination. In our study the key factor in classifying a patient as bone MI or MO was the possibility of surveying the entire skeleton, as is the case in BS, and not that MRI had a higher sensitivity compared to BS when analysis was on a lesion-by-lesion basis. BMS had the same limitations as MRI because the usual bone marrow distribution resulted in a physiologically limited field of view. We conclude that BS remains the method of choice in staging patients with solid tumours despite the fact that MRI is no longer a time-consuming method using FSE sequences. MRI has a complemantary role if special questions remain. BMS appears to have little value in the detection of bone metastases because of its poor specificity, its limited spatial resolution and its restriction to those areas of the skeleton containing haematopoietic marrow. Correspondence to: G.K. v. Schulthess