CLINICAL
AND
LABORATORY OBSERVATIONS
Primary Pericardial Synovial Sarcoma in an Adolescent Patient: Magnetic Resonance and Diffusion-weighted Imaging Features Evrim Ozmen, MD, Yasemin Kayadibi, MD, Cesur Samanci, MD, Nil Ustundag, MD, Gulnihal Ozdemir, MD, Ibrahim Adaletli, MD, and Sebuh Kurugoglu, MD
Summary: Primary synovial sarcomas of the pericardium are extremely rare tumors, especially in pediatric population. As far as we know, only few cases have been reported in the literature. This uncommon location for synovial sarcomas could lead to misdiagnosis. Radiologists and clinicians should be aware of the imaging findings and differential diagnosis of pericardial synovial sarcoma. Herein we presented a 15-year-old boy who had primary pericardial synovial sarcoma with imaging features. Key Words: synovial sarcoma, pericardium, magnetic resonance, MRI, DWI
(J Pediatr Hematol Oncol 2015;37:e230–e233)
S
ynovial sarcomas, which are uncommon malignant softtissue tumors, originate from the mesenchymal cells and differentiate into the neoplastic cells that are similar to the synovial tissue. They frequently affect extremities of young adults. The head, neck, chest, abdomen, and paravertebral areas are other possible locations where the synovial sarcomas may originate from.1,2 However, the pericardium is an unusual place for synovial sarcomas and as far as we know only 2 pediatric cases have been reported in the literature.3,4 Typically, synovial sarcomas have very poor prognosis and most of the patients die within 6 months after the diagnosis.1,3,5,6 In this case report, we present the radiologic findings of primary pericardial sarcoma.
bronchus totally. After the contrast administration, the mass had mild enhancement with contrast material. In addition, subsegmental atelectasis was observed in the lung parenchyma adjacent to the mass regarding to external impression of the mass. There was a slight pericardial effusion. There was no pulmonary nodule with regard to metastasis (Fig. 1). Magnetic resonance (MR) examination was conducted for further assessment of the relationship between the mass and adjacent structures, especially with the myocardium. The mass was hypointense on T1-weighted (W) images, heterogenous hyperintense on T2W images, and it was enhanced heterogenously with contrast material. Diffusionweighted images (DWI) revealed significant restriction of diffusion inside of the tumor (Fig. 2). Biopsy was performed through thoracotomy, and the results of histopathologic examination were compatible with synovial sarcoma (Fig. 3). Surgical treatment was not considered a primary option for this diffusely infiltrating tumor, which could not be totally resected as the tumor encased the major vascular structures and left main bronchus >50% of them. The patient was referred to the oncology department for palliative chemotherapy combined with vincristine, actinomycin D, and cyclophosphamide. It was also planned that the patient would receive radiotherapy after chemotherapy. There was an initial partial response on CT images and he was alive at 4-month followup (Fig. 4). After chemotherapy and radiotherapy, the part of tumor that extended to the left hemithorax and left lung was regressed, whereas the component of tumor at the pericardium adjacent to the left myocardium was relatively stable. Thus, we thought that the tumor arose from the pericardium.
DISCUSSION CASE REPORT A 15-year-old boy presented with complaints of chest pain, shortness of breath, and fever for a period of 3 months. The patient had no additional significant medical, surgical, or family history. On chest x-ray, cardiothoracic ratio was enlarged and cardiophrenic sinus was obscured on the left side. Transthoracic echocardiography revealed a large echogenic mass that involved the pericardium beside the left ventricle, pericardial effusion, and mild mitral insufficiency. Pericardiocentesis was performed and cytologic examination of the bloody pericardial fluid showed that there was not any malignant cell. Computed tomography (CT) of the chest showed a large left mediastinal mass, which was 116 cm in diameter. The mass involved the pericardium, invaded the esophagus, and encased both the left pulmonary artery and left main Received for publication April 9, 2014; accepted November 25, 2014. From the Cerrahpasa Medical School of Istanbul University, Istanbul, Turkey. The authors declare no conflict of interest. Reprints: Cesur Samanci, MD, Cerrahpasa Medical School of Istanbul University, Kocamustafapasa Cd. No:53, Fatih, Istanbul, Turkey (e-mail: [email protected]). Copyright r 2015 Wolters Kluwer Health, Inc. All rights reserved.
e230 | www.jpho-online.com
Primary cardiac tumors are rare neoplasms with 0.001% to 0.03% prevalence in autopsy series, and primary pericardial tumors constitute only 6.7% to 12.8% among them.7–9 Metastases are more common than the primary tumors of the pericardium. The most common primary malignant neoplasm arising from the pericardium is the mesothelioma, followed by sarcomas, lymphoma, and germ cell tumors. Sarcomas are very rare malignant mesenchymal neoplasms and have many subtypes including angiosarcoma, synovial sarcoma, fibrosarcoma, liposarcoma, rhabdomyosarcoma, and undifferentiated sarcoma.7,8 As far we know, the true prevalence of pericardial synovial sarcoma is not known. However, according to systematic review of the literature, there are few case reports about primary pericardial synovial sarcomas with a wide range of age between 13 and 70 years.1,3,5,6 Furthermore, there are only 2 published reports of primary pericardial synovial sarcoma in children.3,4 To the best of our knowledge, there are no data about DWI characteristics of pericardial synovial sarcomas. In our patient, there was a significant diffusion restriction probably due to its higher cellularity. J Pediatr Hematol Oncol
Volume 37, Number 4, May 2015
J Pediatr Hematol Oncol
Volume 37, Number 4, May 2015
FIGURE 1. Axial CT image, which was obtained before chemotherapy, showed the large heterogenous left mediastinal mass enhanced mildly with contrast material after the contrast administration. There was a slight pericardial effusion. Note that the mass is involving the pericardium and circumscribing the left pulmonary vein.
Chest radiography is often used as a first-choice radiologic modality and can depict the enlarged cardio-
Pericardial Synovial Sarcoma: DWI Features
mediastinal silhouette, contour irregularity of the heart, and pericardial effusion. Transthoracic and transesophageal echocardiography could show thickened pericardium, pericardial mass, and effusion. However, those modalities are limited in demonstrating the possible invasion to the mediastinum and lung parenchyma.2,8,9 Cross-sectional imaging modalities including CT and MR can be useful in further characterization of pericardial tumors. Synovial sarcoma is usually seen as a large mass with heterogenous density on CT. In contrast, MR can give better anatomic detail and demonstrate the invasion of the tumor to adjacent structures including the myocardium, great vessels, and cardiac chambers, thanks to its higher contrast resolution. Cardiac MR can also provide additional information about the cardiac function including ventricular volume and mass accurately. This examination requires special imaging protocols, sequences, and parameters. However, we did not obtain functional results with cardiac MR imaging. We just performed conventional chest MR for the assessment of the relationship between the tumor and adjacent structures. Synovial sarcomas appear as heterogenous masses, and there is no specific imaging feature to differentiate it from other sarcomas on MR images. DWI is a technique that depends on the random Brownian motion of water molecules in the
FIGURE 2. A, Axial T2-weighted sequence demonstrated the heterogenous hyperintense mass adjacent to the left ventricle with regard to the pericardial synovial sarcoma. B, Axial T2-weighted image of the upper section showed that the mass extended to the contralateral part of the chest anterior to the vertebrae. C, Diffusion-weighted image showed that the lesion was hyperintense when compared with the adjacent structures D, Apparent diffusion coefficient image revealed a hypointense mass with regard to the significant restriction of diffusion, especially at the left component of the tumor.
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e231
J Pediatr Hematol Oncol
Ozmen et al
Volume 37, Number 4, May 2015
FIGURE 3. A, Hematoxylin and eosin staining of the sample revealed uniform spindle cells inside of the mass. B, Hemotoxylin and eosin staining of the sample showed that a small group of tumoral cells had increased amounts of eosinophilic cytoplasm C, Bcl-2 staining demonstrated strong Bcl-2 immunoreactivity in synovial sarcoma cells D, Epithelial membrane antigen staining showed EMA immunoreactivity in synovial sarcoma cells.
intercellulary space within the voxel. The most established clinical indication for DWI is evaluation of cerebral ischemia. DWI has some advantages as it is noninvasive, does not have the risk of radiation exposure, and does not require contrast
agent administration. Typically, the low values of diffusion that indicate diffusion restriction found in most tumors have been attributed to their increased cellular density.10 DWI might be helpful in diagnosis; however, it could not
FIGURE 4. A, Axial CT image, which was obtained after chemotherapy, showed more homogenous and smaller mass that had partial response to the therapy. The mass encased the left pulmonary artery, and the margins of tumor could not be delineated from the esophagus and aorta. B, Axial CT image of the lower section revealed that the tumor, which was adjacent to the left myocardium, also encased the left pulmonary vein.
e232 | www.jpho-online.com
Copyright
r
2015 Wolters Kluwer Health, Inc. All rights reserved.
J Pediatr Hematol Oncol
Volume 37, Number 4, May 2015
differentiate synovial sarcomas from the other tumors including other sarcomas, primary cardiac tumors, metastases, and mesothelioma. Although positron emission tomography is believed to be useful for distant metastasis, DWI might demonstrate distant metastases as well.2,8,9 Metastasis, mesothelioma, and teratoma can mimic synovial sarcomas. Lung and breast cancers, lymphoma, and leukemia are the most common metastatic neoplasms of the pericardium; however, known history of primary neoplasms could be helpful in the differential diagnosis. Multicystic appearance and the presence of calcification are characteristics of teratomas and they are usually detected in prenatal life by ultrasound. Typically, synovial sarcomas are not in cystic appearance and do not include calcifications. However, they may contain septation. It is very challenging to differentiate synovial sarcoma from mesothelioma either radiologically or pathologically. Pericardial mesothelioma is usually seen as heterogenous soft-tissue mass infiltrating the parietal and visceral pericardium diffusely on both CT and MR imaging, whereas primary synovial sarcoma of the pericardium is usually presented with a solitary large mass. Furthermore, invasion to the adjacent structures is unusual for synovial sarcomas.3,8,9 Surgery is the primary treatment choice for pericardial synovial sarcoma with or without chemotherapy. Although radiotherapy could be helpful to reduce the local invasion, it is not preferred routinely as there are some cardiac complications in long-term follow-up. Prognosis is not promising for synovial sarcomas despite the treatment, and 5-year survival rates of synovial sarcomas is between 36% and 76%.3,5,7
CONCLUSIONS Primary synovial sarcoma of the pericardium is extremely rare entity, especially in pediatric population.
Copyright
r
Pericardial Synovial Sarcoma: DWI Features
This uncommon location could lead to misdiagnosis. MR examination with DWI can be helpful in the diagnosis, evaluation of extension, stage, and response to treatment.
REFERENCES 1. Cheng Y, Sheng W, Zhou X, et al. Pericardial synovial sarcoma, a potential for misdiagnosis: clinicopathologic and molecular cytogenetic analysis of three cases with literature review. Am J Clin Pathol. 2012;137:142–149. 2. O’Sullivan PJ, Harris AC, Munk PL. Radiological features of synovial cell sarcoma. Br J Radiol. 2008;81:346–356. 3. Yoshino M, Sekine Y, Koh E, et al. Pericardial synovial sarcoma: a case report and review of the literature. Surg Today. 2014;44:2167–2173. 4. Hing SN, Marshall L, Al-Saadi R, et al. Primary pericardial synovial sarcoma confirmed by molecular genetic studies: a case report. J Pediatr Hematol Oncol. 2007;29:492–495. 5. Al-Rajhi N, Husain S, Coupland R, et al. Primary pericardial synovial sarcoma: a case report and literature review. J Surg Oncol. 1999;70:194–198. 6. Oizumi S, Igarashi K, Takenaka T, et al. Primary pericardial synovial sarcoma with detection of the chimeric transcript SYT-SSX. Jpn Circ J. 1999;63:330–332. 7. Patel J, Sheppard MN. Pathological study of primary cardiac and pericardial tumours in a specialist UK centre: surgical and autopsy series. Cardiovasc Pathol. 2010;19:343–352. 8. Grebenc ML, Rosado de Christenson ML, Burke AP, et al. Primary cardiac and pericardial neoplasms: radiologic-pathologic correlation. Radiographics. 2000;20:1073–1103. 9. Restrepo CS, Vargas D, Ocazionez D, et al. Primary pericardial tumors. Radiographics. 2013;33:1613–1630. 10. Padhani AR, Liu G, Koh DM, et al. Diffusion-weighted magnetic resonance imaging as a cancer biomarker: consensus and recommendations. Neoplasia. 2009;11:102–125.
2015 Wolters Kluwer Health, Inc. All rights reserved.
www.jpho-online.com |
e233
AND
LABORATORY OBSERVATIONS
Primary Pericardial Synovial Sarcoma in an Adolescent Patient: Magnetic Resonance and Diffusion-weighted Imaging Features Evrim Ozmen, MD, Yasemin Kayadibi, MD, Cesur Samanci, MD, Nil Ustundag, MD, Gulnihal Ozdemir, MD, Ibrahim Adaletli, MD, and Sebuh Kurugoglu, MD
Summary: Primary synovial sarcomas of the pericardium are extremely rare tumors, especially in pediatric population. As far as we know, only few cases have been reported in the literature. This uncommon location for synovial sarcomas could lead to misdiagnosis. Radiologists and clinicians should be aware of the imaging findings and differential diagnosis of pericardial synovial sarcoma. Herein we presented a 15-year-old boy who had primary pericardial synovial sarcoma with imaging features. Key Words: synovial sarcoma, pericardium, magnetic resonance, MRI, DWI
(J Pediatr Hematol Oncol 2015;37:e230–e233)
S
ynovial sarcomas, which are uncommon malignant softtissue tumors, originate from the mesenchymal cells and differentiate into the neoplastic cells that are similar to the synovial tissue. They frequently affect extremities of young adults. The head, neck, chest, abdomen, and paravertebral areas are other possible locations where the synovial sarcomas may originate from.1,2 However, the pericardium is an unusual place for synovial sarcomas and as far as we know only 2 pediatric cases have been reported in the literature.3,4 Typically, synovial sarcomas have very poor prognosis and most of the patients die within 6 months after the diagnosis.1,3,5,6 In this case report, we present the radiologic findings of primary pericardial sarcoma.
bronchus totally. After the contrast administration, the mass had mild enhancement with contrast material. In addition, subsegmental atelectasis was observed in the lung parenchyma adjacent to the mass regarding to external impression of the mass. There was a slight pericardial effusion. There was no pulmonary nodule with regard to metastasis (Fig. 1). Magnetic resonance (MR) examination was conducted for further assessment of the relationship between the mass and adjacent structures, especially with the myocardium. The mass was hypointense on T1-weighted (W) images, heterogenous hyperintense on T2W images, and it was enhanced heterogenously with contrast material. Diffusionweighted images (DWI) revealed significant restriction of diffusion inside of the tumor (Fig. 2). Biopsy was performed through thoracotomy, and the results of histopathologic examination were compatible with synovial sarcoma (Fig. 3). Surgical treatment was not considered a primary option for this diffusely infiltrating tumor, which could not be totally resected as the tumor encased the major vascular structures and left main bronchus >50% of them. The patient was referred to the oncology department for palliative chemotherapy combined with vincristine, actinomycin D, and cyclophosphamide. It was also planned that the patient would receive radiotherapy after chemotherapy. There was an initial partial response on CT images and he was alive at 4-month followup (Fig. 4). After chemotherapy and radiotherapy, the part of tumor that extended to the left hemithorax and left lung was regressed, whereas the component of tumor at the pericardium adjacent to the left myocardium was relatively stable. Thus, we thought that the tumor arose from the pericardium.
DISCUSSION CASE REPORT A 15-year-old boy presented with complaints of chest pain, shortness of breath, and fever for a period of 3 months. The patient had no additional significant medical, surgical, or family history. On chest x-ray, cardiothoracic ratio was enlarged and cardiophrenic sinus was obscured on the left side. Transthoracic echocardiography revealed a large echogenic mass that involved the pericardium beside the left ventricle, pericardial effusion, and mild mitral insufficiency. Pericardiocentesis was performed and cytologic examination of the bloody pericardial fluid showed that there was not any malignant cell. Computed tomography (CT) of the chest showed a large left mediastinal mass, which was 116 cm in diameter. The mass involved the pericardium, invaded the esophagus, and encased both the left pulmonary artery and left main Received for publication April 9, 2014; accepted November 25, 2014. From the Cerrahpasa Medical School of Istanbul University, Istanbul, Turkey. The authors declare no conflict of interest. Reprints: Cesur Samanci, MD, Cerrahpasa Medical School of Istanbul University, Kocamustafapasa Cd. No:53, Fatih, Istanbul, Turkey (e-mail: [email protected]). Copyright r 2015 Wolters Kluwer Health, Inc. All rights reserved.
e230 | www.jpho-online.com
Primary cardiac tumors are rare neoplasms with 0.001% to 0.03% prevalence in autopsy series, and primary pericardial tumors constitute only 6.7% to 12.8% among them.7–9 Metastases are more common than the primary tumors of the pericardium. The most common primary malignant neoplasm arising from the pericardium is the mesothelioma, followed by sarcomas, lymphoma, and germ cell tumors. Sarcomas are very rare malignant mesenchymal neoplasms and have many subtypes including angiosarcoma, synovial sarcoma, fibrosarcoma, liposarcoma, rhabdomyosarcoma, and undifferentiated sarcoma.7,8 As far we know, the true prevalence of pericardial synovial sarcoma is not known. However, according to systematic review of the literature, there are few case reports about primary pericardial synovial sarcomas with a wide range of age between 13 and 70 years.1,3,5,6 Furthermore, there are only 2 published reports of primary pericardial synovial sarcoma in children.3,4 To the best of our knowledge, there are no data about DWI characteristics of pericardial synovial sarcomas. In our patient, there was a significant diffusion restriction probably due to its higher cellularity. J Pediatr Hematol Oncol
Volume 37, Number 4, May 2015
J Pediatr Hematol Oncol
Volume 37, Number 4, May 2015
FIGURE 1. Axial CT image, which was obtained before chemotherapy, showed the large heterogenous left mediastinal mass enhanced mildly with contrast material after the contrast administration. There was a slight pericardial effusion. Note that the mass is involving the pericardium and circumscribing the left pulmonary vein.
Chest radiography is often used as a first-choice radiologic modality and can depict the enlarged cardio-
Pericardial Synovial Sarcoma: DWI Features
mediastinal silhouette, contour irregularity of the heart, and pericardial effusion. Transthoracic and transesophageal echocardiography could show thickened pericardium, pericardial mass, and effusion. However, those modalities are limited in demonstrating the possible invasion to the mediastinum and lung parenchyma.2,8,9 Cross-sectional imaging modalities including CT and MR can be useful in further characterization of pericardial tumors. Synovial sarcoma is usually seen as a large mass with heterogenous density on CT. In contrast, MR can give better anatomic detail and demonstrate the invasion of the tumor to adjacent structures including the myocardium, great vessels, and cardiac chambers, thanks to its higher contrast resolution. Cardiac MR can also provide additional information about the cardiac function including ventricular volume and mass accurately. This examination requires special imaging protocols, sequences, and parameters. However, we did not obtain functional results with cardiac MR imaging. We just performed conventional chest MR for the assessment of the relationship between the tumor and adjacent structures. Synovial sarcomas appear as heterogenous masses, and there is no specific imaging feature to differentiate it from other sarcomas on MR images. DWI is a technique that depends on the random Brownian motion of water molecules in the
FIGURE 2. A, Axial T2-weighted sequence demonstrated the heterogenous hyperintense mass adjacent to the left ventricle with regard to the pericardial synovial sarcoma. B, Axial T2-weighted image of the upper section showed that the mass extended to the contralateral part of the chest anterior to the vertebrae. C, Diffusion-weighted image showed that the lesion was hyperintense when compared with the adjacent structures D, Apparent diffusion coefficient image revealed a hypointense mass with regard to the significant restriction of diffusion, especially at the left component of the tumor.
Copyright
r
2015 Wolters Kluwer Health, Inc. All rights reserved.
www.jpho-online.com |
e231
J Pediatr Hematol Oncol
Ozmen et al
Volume 37, Number 4, May 2015
FIGURE 3. A, Hematoxylin and eosin staining of the sample revealed uniform spindle cells inside of the mass. B, Hemotoxylin and eosin staining of the sample showed that a small group of tumoral cells had increased amounts of eosinophilic cytoplasm C, Bcl-2 staining demonstrated strong Bcl-2 immunoreactivity in synovial sarcoma cells D, Epithelial membrane antigen staining showed EMA immunoreactivity in synovial sarcoma cells.
intercellulary space within the voxel. The most established clinical indication for DWI is evaluation of cerebral ischemia. DWI has some advantages as it is noninvasive, does not have the risk of radiation exposure, and does not require contrast
agent administration. Typically, the low values of diffusion that indicate diffusion restriction found in most tumors have been attributed to their increased cellular density.10 DWI might be helpful in diagnosis; however, it could not
FIGURE 4. A, Axial CT image, which was obtained after chemotherapy, showed more homogenous and smaller mass that had partial response to the therapy. The mass encased the left pulmonary artery, and the margins of tumor could not be delineated from the esophagus and aorta. B, Axial CT image of the lower section revealed that the tumor, which was adjacent to the left myocardium, also encased the left pulmonary vein.
e232 | www.jpho-online.com
Copyright
r
2015 Wolters Kluwer Health, Inc. All rights reserved.
J Pediatr Hematol Oncol
Volume 37, Number 4, May 2015
differentiate synovial sarcomas from the other tumors including other sarcomas, primary cardiac tumors, metastases, and mesothelioma. Although positron emission tomography is believed to be useful for distant metastasis, DWI might demonstrate distant metastases as well.2,8,9 Metastasis, mesothelioma, and teratoma can mimic synovial sarcomas. Lung and breast cancers, lymphoma, and leukemia are the most common metastatic neoplasms of the pericardium; however, known history of primary neoplasms could be helpful in the differential diagnosis. Multicystic appearance and the presence of calcification are characteristics of teratomas and they are usually detected in prenatal life by ultrasound. Typically, synovial sarcomas are not in cystic appearance and do not include calcifications. However, they may contain septation. It is very challenging to differentiate synovial sarcoma from mesothelioma either radiologically or pathologically. Pericardial mesothelioma is usually seen as heterogenous soft-tissue mass infiltrating the parietal and visceral pericardium diffusely on both CT and MR imaging, whereas primary synovial sarcoma of the pericardium is usually presented with a solitary large mass. Furthermore, invasion to the adjacent structures is unusual for synovial sarcomas.3,8,9 Surgery is the primary treatment choice for pericardial synovial sarcoma with or without chemotherapy. Although radiotherapy could be helpful to reduce the local invasion, it is not preferred routinely as there are some cardiac complications in long-term follow-up. Prognosis is not promising for synovial sarcomas despite the treatment, and 5-year survival rates of synovial sarcomas is between 36% and 76%.3,5,7
CONCLUSIONS Primary synovial sarcoma of the pericardium is extremely rare entity, especially in pediatric population.
Copyright
r
Pericardial Synovial Sarcoma: DWI Features
This uncommon location could lead to misdiagnosis. MR examination with DWI can be helpful in the diagnosis, evaluation of extension, stage, and response to treatment.
REFERENCES 1. Cheng Y, Sheng W, Zhou X, et al. Pericardial synovial sarcoma, a potential for misdiagnosis: clinicopathologic and molecular cytogenetic analysis of three cases with literature review. Am J Clin Pathol. 2012;137:142–149. 2. O’Sullivan PJ, Harris AC, Munk PL. Radiological features of synovial cell sarcoma. Br J Radiol. 2008;81:346–356. 3. Yoshino M, Sekine Y, Koh E, et al. Pericardial synovial sarcoma: a case report and review of the literature. Surg Today. 2014;44:2167–2173. 4. Hing SN, Marshall L, Al-Saadi R, et al. Primary pericardial synovial sarcoma confirmed by molecular genetic studies: a case report. J Pediatr Hematol Oncol. 2007;29:492–495. 5. Al-Rajhi N, Husain S, Coupland R, et al. Primary pericardial synovial sarcoma: a case report and literature review. J Surg Oncol. 1999;70:194–198. 6. Oizumi S, Igarashi K, Takenaka T, et al. Primary pericardial synovial sarcoma with detection of the chimeric transcript SYT-SSX. Jpn Circ J. 1999;63:330–332. 7. Patel J, Sheppard MN. Pathological study of primary cardiac and pericardial tumours in a specialist UK centre: surgical and autopsy series. Cardiovasc Pathol. 2010;19:343–352. 8. Grebenc ML, Rosado de Christenson ML, Burke AP, et al. Primary cardiac and pericardial neoplasms: radiologic-pathologic correlation. Radiographics. 2000;20:1073–1103. 9. Restrepo CS, Vargas D, Ocazionez D, et al. Primary pericardial tumors. Radiographics. 2013;33:1613–1630. 10. Padhani AR, Liu G, Koh DM, et al. Diffusion-weighted magnetic resonance imaging as a cancer biomarker: consensus and recommendations. Neoplasia. 2009;11:102–125.
2015 Wolters Kluwer Health, Inc. All rights reserved.
www.jpho-online.com |
e233
