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Dynamic CT features of mediastinal hemangioma: more information for evaluation
Journal of Clinical Imaging 24 (2000) 276 ± 278
Dynamic CT features of mediastinal hemangioma More information for evaluation Yun-Chung Cheung*, Shu-Hang Ng, Yung-Liang Wan, Chih-Feng Tan, Ho-Fai Wong, Koon-Kwan Ng First Department of Diagnostic Radiology, Chang Gung Medical Center at Linkou and Keelung, Chang Gung Medical College, Chang Gung University, 5 Fu-Hsing Street, Kwei Shan Hsiang, Tao Yuan Hsien, Taiwan Received 1 August 2000
Abstract Dynamic enhancing feature in mediastinal hemangioma was rarely reported. Slow, gradually increasing and prolonged contrast stains are the diagnostic hints in our case that avoid the hemorrhagic catastrophe from transthoracic core needle biopsy. A rare finding of an aberrant vessel entering into the tumor was valuable for operative planning. Dynamic computed tomography (CT) can provide more information for evaluation in such cases. D 2001 Elsevier Science Inc. All rights reserved. Keywords: Mediastinum; Hemangioma; Needle biopsy; Computed tomography
1. Introduction Mediastinal hemangiomas are uncommon benign vascular tumors that account for less than 0.5% of all mediastinal masses [1,2]. The preoperative diagnosis of these tumors is seldom attainable. Cohen et al. [1] even stated that radiological studies, including computed tomography (CT), offered little in the preoperative diagnosis. Phleboliths or the peripheral `puddling' contrast enhancement is potentially diagnostic finding for such vascular tumors [2,3]. Dynamic CT is widely applied in evaluation of abdominal hemangiomas, but is rarely reported in mediastinal hemangiomas. Herein, we report a case of mediastinal hemangioma, presenting with suggestive enhancing features that avoided hemorrhagic catastrophe from core needle biopsy. The CT features will be discussed.
by chest radiography taken for a week. Physical examination and laboratory data were unremarkable. The previous CT performed in a local hospital showed a heterogeneously enhancing mass in the superior mediastinum. A specific
2. Case report A 19-year-old healthy man was admitted because of a superior mediastinal mass that was incidentally discovered * Corresponding author. Tel.: +886-3-3281200 ext. 2575; fax: +886-33330365. E-mail address: [email protected] (Y.-C. Cheung).
Fig. 1. Dynamic CT scans at the approximate levels consisting of (A) precontrast, (B) 30 s, (C) 3 min, (D) 5 min after a bolus injection of contrast medium show an ill-defined mediastinal mass consisting of gradually enhancing areas (arrowheads). The enhancement is gradually increased and persisted. The mass shows infiltrating with multiple enhancing vessels in the preaortic region.
0899-7071/01/$ ± see front matter D 2001 Elsevier Science Inc. All rights reserved. PII: S 0 8 9 9 - 7 0 7 1 ( 0 0 ) 0 0 2 2 3 - 0
Y.-C. Cheung et al. / Journal of Clinical Imaging 24 (2000) 276±278
Fig. 2. Reconstruction of CT scans (left oblique view) obtained at 30 s after contrast medium injection shows an aberrant vein (arrow) originating from left brachiocephalic vein and entering the mass.
diagnosis was not made. He has subsequently consulted us for a CT-guided core needle biopsy. Due to the infiltrating appearance admixing with fatty components, hemangioma was included in the differential diagnosis. In order to evaluate the nature and vascularity of the mass before biopsy, we performed a dynamic CT study with a bolus injection of 100 ml contrast medium at the rate of 2 ml/s by powerful injector via the left antecubital vein. Spiral scanning of the mediastinal mass was done repeatedly at 30 s, 3 min and 5 min after injection. CT showed an ill-defined infiltrating mediastinal mass consisting of inhomogeneously enhanced areas. The enhancement gradually increased with time and persisted on the delayed scans (Fig. 1). In addition, a vascular structure, originating from the left brachiocephalic vein and coursing downward into the mass, was clearly seen on the scans made at 30 s after injection (Fig. 2). The mass extended to the preaortic fossa and the left hilum, and closely abutted the left atrium. Mediastinal hemangioma was tentatively diagnosed due to the delay washout of contrast medium within the tumor. The CT-guided biopsy was cancelled because of the risk of substantial bleeding. At surgery, a 15 12 cm nonencapsulated mediastinal mass adhered to the left pulmonary artery and vein. After the ligation of the aberrant vein from the left brachiocephalic vein, subtotal excision of the tumor was performed. Histologic evaluation revealed many large dilated and congested vascular spaces as well as abnormal thickened vessels and foci of organizing thrombi. The diagnosis of cavernous hemangioma was confirmed. 3. Discussion Mediastinal hemangiomas typically occur in a young population; approximately 75% manifest before the age of 35 years [2]. Most patients are asymptomatic at presentation; however, some may present with nonspecific symptoms, such as cough, chest pain and dyspnea due to compression or invasion of adjacent structures [1,2]. At histologic examination, these tumors are composed of
277
large, interconnecting vascular spaces interposed with various stromal elements such as fat, myxoid and fibrous tissues. Organized thrombi are frequent. The thrombi may calcify as phleboliths that are a reliable diagnostic feature of hemangiomas [2,4]. The tumors are categorized according to the size of their vascular spaces as capillary, cavernous or venous hemangiomas. Grossly, they are mostly well circumscribed, but rarely have true capsule [5]. The lack of true capsule and of surrounding compressible tissue in mediastinum can explain why it has a high risk of hemorrhage for core needle biopsy. Although true hemangiomas are always benign, histologic evaluation is still necessary to differentiate them from malignant vascular tumors such as hemangioendotheliomas and hemangiopericytomas. Transthoracic needle aspiration biopsy of mediastinal hemangiomas has been reported to be of little diagnostic use [1,6]. Since core needle biopsy was controversially avoided in mediastinal hemangioma, surgery is the recommended course of treatment; nevertheless, the procedure is still hazardous due to the potential complication of substantial blood loss. On CT, various enhancement patterns have been reported including central, mixed central and peripheral, peripheral, and nonspecific increased attenuation [7]. The presence of intratumoral thrombi and slow infusion of contrast medium hamper the development of central enhancement, and frequently result in heterogeneous enhancement. Therefore, preoperative diagnosis may not be achieved easily. Dynamic enhanced CT of hemangiomas elsewhere in the body shows gradually increased and persistent enhancement of the mass due to the delayed washout. In fact, there is no distinguishable histologic architecture between these hemangiomas in mediastinum and body. To our knowledge, the dynamic features were rarely reported in the mediastinal hemangioma, probably due to the rarity of this tumor. In our case, the early scans revealed enhancing areas within the tumor. In the delay scans, the enhancement was persisting and gradually increased with time. Although the early scans were not diagnostic, the delayed washout effect of contrast medium was a big hint in suspecting this tumor. Scanning in different phases of this tumor provided different information that benefits for diagnosis. Not only demonstrating the enhancing pattern of the tumor, the early scans also revealed an aberrant vessel from the brachiocephalic vein that was valuable for operative planning. Without this information, hemorrhagic catastrophe may occur during the biopsy or the operation. In conclusion, dynamic spiral CT can provide more valuable information for evaluation in such cases of mediastinal hemangioma.
References [1] Cohen AJ, Sbaschnig RJ, Hochholzer L, Lough FC, Albus RA. Mediastinal hemangiomas. Ann Thorac Surg 1987;43:656 ± 9.
278
Y.-C. Cheung et al. / Journal of Clinical Imaging 24 (2000) 276±278
[2] Davis JM, Mark GJ, Greene R. Benign blood vascular tumors of the mediastinum. Radiology 1978;126:581 ± 7. [3] Seline TH, Gross BH, Francis IR. CT and MR imaging of mediastinal hemangiomas. J Comput Assisted Tomogr 1990;14: 766 ± 8. [4] Gindhart TD, Tucker WY, Choy SH. Cavernous hemangioma of the superior mediastinum. Am J Surg Pathol 1979;3:353 ± 61.
[5] Marchevsky AM, Kanebo M. Surgical pathology of the mediastinum. New York, NY: Raven Press, 1984. pp. 239 ± 44. [6] Schurawitzki H, Stiglbauer R, Klepetko W, Eckersberger F. CT and MRI in benign mediastinal hemangioma. Clin Radiol 1991;43: 91 ± 4. [7] McAdams HP, Rosado-de-Christenson ML, Moran CA. Mediastinal hemangioma: radiographic and CT features in 14 patients. Radiology 1994;193:399 ± 402.
Dynamic CT features of mediastinal hemangioma More information for evaluation Yun-Chung Cheung*, Shu-Hang Ng, Yung-Liang Wan, Chih-Feng Tan, Ho-Fai Wong, Koon-Kwan Ng First Department of Diagnostic Radiology, Chang Gung Medical Center at Linkou and Keelung, Chang Gung Medical College, Chang Gung University, 5 Fu-Hsing Street, Kwei Shan Hsiang, Tao Yuan Hsien, Taiwan Received 1 August 2000
Abstract Dynamic enhancing feature in mediastinal hemangioma was rarely reported. Slow, gradually increasing and prolonged contrast stains are the diagnostic hints in our case that avoid the hemorrhagic catastrophe from transthoracic core needle biopsy. A rare finding of an aberrant vessel entering into the tumor was valuable for operative planning. Dynamic computed tomography (CT) can provide more information for evaluation in such cases. D 2001 Elsevier Science Inc. All rights reserved. Keywords: Mediastinum; Hemangioma; Needle biopsy; Computed tomography
1. Introduction Mediastinal hemangiomas are uncommon benign vascular tumors that account for less than 0.5% of all mediastinal masses [1,2]. The preoperative diagnosis of these tumors is seldom attainable. Cohen et al. [1] even stated that radiological studies, including computed tomography (CT), offered little in the preoperative diagnosis. Phleboliths or the peripheral `puddling' contrast enhancement is potentially diagnostic finding for such vascular tumors [2,3]. Dynamic CT is widely applied in evaluation of abdominal hemangiomas, but is rarely reported in mediastinal hemangiomas. Herein, we report a case of mediastinal hemangioma, presenting with suggestive enhancing features that avoided hemorrhagic catastrophe from core needle biopsy. The CT features will be discussed.
by chest radiography taken for a week. Physical examination and laboratory data were unremarkable. The previous CT performed in a local hospital showed a heterogeneously enhancing mass in the superior mediastinum. A specific
2. Case report A 19-year-old healthy man was admitted because of a superior mediastinal mass that was incidentally discovered * Corresponding author. Tel.: +886-3-3281200 ext. 2575; fax: +886-33330365. E-mail address: [email protected] (Y.-C. Cheung).
Fig. 1. Dynamic CT scans at the approximate levels consisting of (A) precontrast, (B) 30 s, (C) 3 min, (D) 5 min after a bolus injection of contrast medium show an ill-defined mediastinal mass consisting of gradually enhancing areas (arrowheads). The enhancement is gradually increased and persisted. The mass shows infiltrating with multiple enhancing vessels in the preaortic region.
0899-7071/01/$ ± see front matter D 2001 Elsevier Science Inc. All rights reserved. PII: S 0 8 9 9 - 7 0 7 1 ( 0 0 ) 0 0 2 2 3 - 0
Y.-C. Cheung et al. / Journal of Clinical Imaging 24 (2000) 276±278
Fig. 2. Reconstruction of CT scans (left oblique view) obtained at 30 s after contrast medium injection shows an aberrant vein (arrow) originating from left brachiocephalic vein and entering the mass.
diagnosis was not made. He has subsequently consulted us for a CT-guided core needle biopsy. Due to the infiltrating appearance admixing with fatty components, hemangioma was included in the differential diagnosis. In order to evaluate the nature and vascularity of the mass before biopsy, we performed a dynamic CT study with a bolus injection of 100 ml contrast medium at the rate of 2 ml/s by powerful injector via the left antecubital vein. Spiral scanning of the mediastinal mass was done repeatedly at 30 s, 3 min and 5 min after injection. CT showed an ill-defined infiltrating mediastinal mass consisting of inhomogeneously enhanced areas. The enhancement gradually increased with time and persisted on the delayed scans (Fig. 1). In addition, a vascular structure, originating from the left brachiocephalic vein and coursing downward into the mass, was clearly seen on the scans made at 30 s after injection (Fig. 2). The mass extended to the preaortic fossa and the left hilum, and closely abutted the left atrium. Mediastinal hemangioma was tentatively diagnosed due to the delay washout of contrast medium within the tumor. The CT-guided biopsy was cancelled because of the risk of substantial bleeding. At surgery, a 15 12 cm nonencapsulated mediastinal mass adhered to the left pulmonary artery and vein. After the ligation of the aberrant vein from the left brachiocephalic vein, subtotal excision of the tumor was performed. Histologic evaluation revealed many large dilated and congested vascular spaces as well as abnormal thickened vessels and foci of organizing thrombi. The diagnosis of cavernous hemangioma was confirmed. 3. Discussion Mediastinal hemangiomas typically occur in a young population; approximately 75% manifest before the age of 35 years [2]. Most patients are asymptomatic at presentation; however, some may present with nonspecific symptoms, such as cough, chest pain and dyspnea due to compression or invasion of adjacent structures [1,2]. At histologic examination, these tumors are composed of
277
large, interconnecting vascular spaces interposed with various stromal elements such as fat, myxoid and fibrous tissues. Organized thrombi are frequent. The thrombi may calcify as phleboliths that are a reliable diagnostic feature of hemangiomas [2,4]. The tumors are categorized according to the size of their vascular spaces as capillary, cavernous or venous hemangiomas. Grossly, they are mostly well circumscribed, but rarely have true capsule [5]. The lack of true capsule and of surrounding compressible tissue in mediastinum can explain why it has a high risk of hemorrhage for core needle biopsy. Although true hemangiomas are always benign, histologic evaluation is still necessary to differentiate them from malignant vascular tumors such as hemangioendotheliomas and hemangiopericytomas. Transthoracic needle aspiration biopsy of mediastinal hemangiomas has been reported to be of little diagnostic use [1,6]. Since core needle biopsy was controversially avoided in mediastinal hemangioma, surgery is the recommended course of treatment; nevertheless, the procedure is still hazardous due to the potential complication of substantial blood loss. On CT, various enhancement patterns have been reported including central, mixed central and peripheral, peripheral, and nonspecific increased attenuation [7]. The presence of intratumoral thrombi and slow infusion of contrast medium hamper the development of central enhancement, and frequently result in heterogeneous enhancement. Therefore, preoperative diagnosis may not be achieved easily. Dynamic enhanced CT of hemangiomas elsewhere in the body shows gradually increased and persistent enhancement of the mass due to the delayed washout. In fact, there is no distinguishable histologic architecture between these hemangiomas in mediastinum and body. To our knowledge, the dynamic features were rarely reported in the mediastinal hemangioma, probably due to the rarity of this tumor. In our case, the early scans revealed enhancing areas within the tumor. In the delay scans, the enhancement was persisting and gradually increased with time. Although the early scans were not diagnostic, the delayed washout effect of contrast medium was a big hint in suspecting this tumor. Scanning in different phases of this tumor provided different information that benefits for diagnosis. Not only demonstrating the enhancing pattern of the tumor, the early scans also revealed an aberrant vessel from the brachiocephalic vein that was valuable for operative planning. Without this information, hemorrhagic catastrophe may occur during the biopsy or the operation. In conclusion, dynamic spiral CT can provide more valuable information for evaluation in such cases of mediastinal hemangioma.
References [1] Cohen AJ, Sbaschnig RJ, Hochholzer L, Lough FC, Albus RA. Mediastinal hemangiomas. Ann Thorac Surg 1987;43:656 ± 9.
278
Y.-C. Cheung et al. / Journal of Clinical Imaging 24 (2000) 276±278
[2] Davis JM, Mark GJ, Greene R. Benign blood vascular tumors of the mediastinum. Radiology 1978;126:581 ± 7. [3] Seline TH, Gross BH, Francis IR. CT and MR imaging of mediastinal hemangiomas. J Comput Assisted Tomogr 1990;14: 766 ± 8. [4] Gindhart TD, Tucker WY, Choy SH. Cavernous hemangioma of the superior mediastinum. Am J Surg Pathol 1979;3:353 ± 61.
[5] Marchevsky AM, Kanebo M. Surgical pathology of the mediastinum. New York, NY: Raven Press, 1984. pp. 239 ± 44. [6] Schurawitzki H, Stiglbauer R, Klepetko W, Eckersberger F. CT and MRI in benign mediastinal hemangioma. Clin Radiol 1991;43: 91 ± 4. [7] McAdams HP, Rosado-de-Christenson ML, Moran CA. Mediastinal hemangioma: radiographic and CT features in 14 patients. Radiology 1994;193:399 ± 402.