- Email: [email protected]
Focal hepatic lesions mimicking cavernous hemangioma supplied by the portal vein
Hepatology Research 36 (2006) 70–73
Case report
Focal hepatic lesions mimicking cavernous hemangioma supplied by the portal vein Shiro Miyayama a,∗ , Osamu Matsui c , Yoh Zen d , Masashi Yamashiro a , Yasuji Ryu a , Tetsuya Minami c , Kazuo Notsumata b , Nobuyoshi Tanaka b a
Department of Diagnostic Radiology, Fukuiken Saiseikai Hospital, 7-1 Funabashi, Wadanaka-cho, Fukui 918-8503, Japan b Department of Internal Medicine, Fukuiken Saiseikai Hospital, 7-1 Funabashi, Wadanaka-cho, Fukui 918-8503, Japan c Department of Radiology, Kanazawa University Graduate School of Medical Science, 13-1 Takara-machi, Kanazawa 920-8461, Japan d Department of Pathology, Kanazawa University Graduate School of Medical Science, 13-1 Takara-machi, Kanazawa 920-8461, Japan Received 19 February 2006; received in revised form 21 May 2006; accepted 9 June 2006 Available online 13 July 2006
Abstract We report that imaging findings of focal hepatic lesion mimicking cavernous hemangioma supplied by the portal vein, which showed delayed enhancement on CT and hyperintensity similar to that of cerebrospinal fluid on T2-weighted MR images. Biopsy specimen showed the dilated portal veins and hyperplastic change in the surrounding liver parenchyma. CT during arterial portography (CTAP), in particular single-level dynamic CTAP, could clearly depict the abnormal dilated portal vein in the lesion and facilitated the diagnosis of this condition. © 2006 Elsevier Ireland Ltd. All rights reserved. Keywords: Focal hepatic lesion; Portal blood supply
1. Introduction Vascular malformations and hemangiomas are endothelial malformations and that may arise in anywhere in the body [1]. Several vascular malformations other than cavernous hemangioma have also been reported in the liver [2–7]. We encountered a case showing localized dilatation of the portal vein mimicking hepatic cavernous hemangioma supplied by the portal vein. In this report, we describe the radiological findings.
2. Case report A 48-year-old man was referred to our hospital for examination of focal hepatic lesions. He did not have any symptoms or signs of chronic liver disease. He did not have a daily ∗
Corresponding author. Tel.: +81 776 23 1111; fax: +81 776 28 8519. E-mail address: [email protected] (S. Miyayama).
1386-6346/$ – see front matter © 2006 Elsevier Ireland Ltd. All rights reserved. doi:10.1016/j.hepres.2006.06.010
drinking habit or a history of steroid administration and hepatic function was normal. Unenhanced CT showed multiple hypodense masses in the right lobe of the liver (Fig. 1a). The diameter of the maximal lesion was 7.5 cm at the posterior superior subsegment and other lesions ranged from 1 to 1.5 cm in diameter. On arterial phase CT, all lesions showed partial enhancement (Fig. 1b), and gradual fill-in and homogenous or inhomogenous enhancement was seen on equilibrium-phase CT (Fig. 1c). The lesions appeared hypointense on T1-weighted MR image and hyperintense similar to that of cerebrospinal fluid on T2-weighted MR image (Fig. 2). Hepatic arteriograms and CTHA did not show any abnormalities corresponding to the hepatic lesions other than a small stain suspected of being a cavernous hemangioma in the right lobe of the liver. On CTAP, all lesions were demonstrated as a hypodense mass containing dilated vessels connected to the portal vein at the periphery or center of the lesions (Fig. 3). Single-level dynamic CTAP was performed targeting the largest 7.5-cm lesion, followed by CTAP. Scanning began 5 s after injection of contrast material, and a 30-s continuous scan with a 2-mm collimation was obtained in
S. Miyayama et al. / Hepatology Research 36 (2006) 70–73
71
Fig. 1. (a) Unenhanced CT shows two hypodense mass lesions 7.5 cm (arrow) and 1 cm (arrowhead) in diameter in the right lobe of the liver. (b) Arterial phase CT shows partial enhancement of both large (arrow) and small lesions (arrowhead). (c) On equilibrium-phase CT, the largest lesion shows inhomogenous enhancement. The small lesion also becomes slightly hyperdense.
a single breath hold without table feed. Images were reconstructed at 0.2-s intervals with a small field of view targeting the lesion. Single-level dynamic CTAP clearly showed that contrast material slowly filled the dilated anomalous poste-
rior superior portal branch and the whole lesion was gradually enhanced (Fig. 4). Three-dimensional CT portography created from CTAP images also showed the dilated anomalous portal branch (Fig. 5).
Fig. 2. T2-weighted MR image demonstrates all lesions as hyperintense (arrow and arrowhead).
Fig. 3. CT during arterial portography (CTAP) shows the dilated portal vein in not only the large hypodense mass but also the small hypodense lesions (arrows).
72
S. Miyayama et al. / Hepatology Research 36 (2006) 70–73
Fig. 6. Histologically, the dilated portal veins and hyperplastic change in the surrounding liver parenchyma are seen. Hepatocytes in the surrounding liver parenchyma does not demonstrate atypia. Portal vein branches (PV) are dilated compared to neighboring hepatic artery (arrow) and bile ducts (arrowheads) (hematoxylin and eosin staining, 100×).
On sonography, the maximal lesion was depicted as an inhomogenous slightly hyperechoic mass with hypoechoic areas but other small lesions were not depicted. Biopsy specimen using an 18-G cutting needle (Max Core; Bard, Covington, GA) was obtained at the periphery of the maximal lesion under sonographic guidance. Histologically, the dilated portal veins and hyperplastic change in the surrounding liver parenchyma were seen. Hepatocytes in the surrounding liver parenchyma did not demonstrate atypia (Fig. 6). Anomalous dilatation of the portal vein was suspected, but the final diagnosis could not be established. None of the lesions showed any change over a 3-year follow-up period. Fig. 4. (a) Single-level dynamic CTAP image obtained 12 s after contrast material injection shows that the dilated portal veins are gradually opacified in both in large (arrow) and small (arrowhead) lesions. (b) Single-level dynamic CTAP image obtained 28 s after contrast material injection shows that the entire mass lesion becomes gradually enhanced.
Fig. 5. Three-dimensional CT portography clearly shows the dilated abnormal portal vein (arrow).
3. Discussion In the present case, hepatic cavernous hemangioma was initially suspected because of delayed enhancement on equilibrium-phase CT and hyperintensity on T2-weighted MR images. However, hepatic angiograms and CTHA did not show any findings corresponding to the lesion. Portal phase images of the superior mesenteric arteriogram showed a dilated portal vein and CTAP demonstrated that the dilated portal vein was located within the lesion. In particular, singlelevel dynamic CTAP could clearly depict gradual opacifying of the abnormal dilated portal vein in the largest lesion over time. The blood flow of the dilated anomalous portal vein was very slow; therefore, CT and MR image findings mimicked hepatic cavernous hemangioma. Several hepatic vascular anomalies, such as intrahepatic portosystemic venous shunt, peliosis hepatis, portal vein aneurysm, and hepatic sinusoidal dilatation, have been reported [2–7]. However, the imaging findings of our case did not correspond to any well-known abnormality. To our knowl-
S. Miyayama et al. / Hepatology Research 36 (2006) 70–73
edge, the literature contains only one case report by Arai et al. [8], which described the same condition as unusual multiple cavernous hemangiomas supplied by the portal vein. They also indicated that their diagnosis was tentative and might be reclassified as another category than hepatic cavernous hemangioma. Hepatic cavernous hemangioma is the most common benign hepatic tumor and has characteristic imaging findings [1]. Peripheral globular enhancement of the lesion on the arterial phase, centripetal enhancement that progresses to uniform filling in the tumor on the venous phase, and persistent enhancement on the delayed phase are seen on dynamic CT or MR images. Hyperintensity similar to that of cerebrospinal fluid on T2-weighted MR images is another characteristic finding. Several atypical hepatic hemangiomas have been reported [9,10]; however, these are usually supplied from the hepatic artery. In addition, contrast material usually enters the lesion from multiple points at the periphery of the lesion. In the present case, however, the contrast material entered the lesion from one point at the periphery or center of the lesion. We speculate that one lesion may be supplied by one dilated abnormal portal branch that the blood flows very slowly; this condition should be called localized portal vein dilatation, not cavernous hemangioma supplied by the portal vein. Hepatic angiosarcoma must also be considered in the differential diagnosis [11,12]. This tumor is the most common malignant mesenchymal tumor of the liver and rarely mimics hepatic cavernous hemangioma [12]. However, this tumor is also depicted on the arterial side on angiography, and usually shows rapid tumor growth [11,12]. Peliosis hepatis is an unusual disorder characterized by multiple blood-filled spaces within the liver. It is divided into two types: parenchymal and phlebectatic [3–6]. In the former, the blood-filled spaces have no endothelial lining and are usually associated with hemorrhagic parenchymal necrosis. In the latter, the spaces are lined with endothelium and are based on aneurysmal dilatation of the central vein. In both types, the abnormal findings are usually seen on the late arterial phase of the hepatic angiogram. Hepatic sinusoidal dilatation is another consideration in the differential diagnosis [7]. It usually occurs in young women with a history of long-term oral contraceptive use. Microscopically, hepatic sinusoidal dilatation is characterized by focal dilatation of the sinusoidal spaces associated with hepatocyte atrophy and necrosis. Hepatic sinusoidal dilatation is heterogeneously hypodense on portal phase CT and slightly hyperintense on T2-weighted MR images.
73
CTAP, in particular single-level dynamic CTAP, shows characteristic findings of this condition; however, CT and MR imaging findings for the present case mimicked those of hepatic cavernous hemangioma. We speculate that this condition may be misdiagnosed as hepatic cavernous hemangioma without performing CTAP, especially in the small lesions, although this condition may be rare. Clinically, however, a clear differential diagnosis between this condition and cavernous hemangioma may not be necessary because both are apparently benign. The portal venous phase CT images may depict the dilated portal vein entering into the lesion and may facilitate diagnosis of this condition; however, we did not obtain these images in this case. In summary, we reported a case of focal hepatic lesions mimicking hepatic cavernous hemangioma supplied by the portal vein. CTAP, in particular single-level dynamic CTAP, was useful to confirm this abnormality. A final diagnosis of this lesion could not be established, but should be categorized in terms of vascular malformations in the future.
References [1] Donnelly LF, Adams DM, Bisset III GS. Vascular malformations and hemangiomas: a practical approach in a multidisciplinary clinic. Am J Roentgenol 2000;174:597–608. [2] Ito K, Matsunaga N, Mitchell DG, et al. Imaging of congenital abnormalities of the portal venous system. Am J Roentgenol 1997;168: 233–7. [3] Pliskin M. Peliosis hepatis. Radiology 1975;114:29–30. [4] Tsukamoto Y, Nakata H, Kimoto T, Noda T, Kuroda Y, Haratake J. CT and angiography of peliosis hepatis. Am J Roentgenol 1984;142:539–40. [5] Maves CK, Caron KH, Bisset III GS, Agarwal R. Splenic and hepatic peliosis: MR findings. Am J Roentgenol 1992;158:75–6. [6] Radin DR, Kanel GC. Peliosis hepatis in a patient with human immunodeficiency virus infection. Am J Roentgenol 1991;156:91–2. [7] Yang DM, Jung DH, Park CH, Kim JE, Choi SJ. Imaging findings of hepatic sinusoidal dilatation. Am J Roentgenol 2004;183:1075–7. [8] Arai K, Matsui O, Kadoya M, et al. Unusual multiple cavernous hemangiomas of the liver supplied by portal blood. Diag Imag Abdomen 1990;10:570–4 (in Japanese). [9] Vilgrain V, Boulos L, Vullierme M-P, Denys A, Terris B, Menu Y. Imaging of atypical hemangiomas of the liver with pathologic correlation. RadioGraphics 2000;20:379–97. [10] Jang HJ, Kim TK, Lim HK, et al. Hepatic hemangioma: atypical appearances on CT, MR imaging, and sonography. Am J Roentgenol 2003;180:135–41. [11] Koyama T, Fletcher JG, Johnson CD, Kuo MS, Notohara K, Burgart LJ. Primary hepatic angiosarcoma: findings at CT and MR imaging. Radiology 2002;222:667–73. [12] Peterson MS, Baron RL, Rankin SC. Hepatic angiosarcoma: findings on multiphasic contrast-enhanced helical CT do not mimic hepatic hemangioma. Am J Roentgenol 2000;175:165–70.
Case report
Focal hepatic lesions mimicking cavernous hemangioma supplied by the portal vein Shiro Miyayama a,∗ , Osamu Matsui c , Yoh Zen d , Masashi Yamashiro a , Yasuji Ryu a , Tetsuya Minami c , Kazuo Notsumata b , Nobuyoshi Tanaka b a
Department of Diagnostic Radiology, Fukuiken Saiseikai Hospital, 7-1 Funabashi, Wadanaka-cho, Fukui 918-8503, Japan b Department of Internal Medicine, Fukuiken Saiseikai Hospital, 7-1 Funabashi, Wadanaka-cho, Fukui 918-8503, Japan c Department of Radiology, Kanazawa University Graduate School of Medical Science, 13-1 Takara-machi, Kanazawa 920-8461, Japan d Department of Pathology, Kanazawa University Graduate School of Medical Science, 13-1 Takara-machi, Kanazawa 920-8461, Japan Received 19 February 2006; received in revised form 21 May 2006; accepted 9 June 2006 Available online 13 July 2006
Abstract We report that imaging findings of focal hepatic lesion mimicking cavernous hemangioma supplied by the portal vein, which showed delayed enhancement on CT and hyperintensity similar to that of cerebrospinal fluid on T2-weighted MR images. Biopsy specimen showed the dilated portal veins and hyperplastic change in the surrounding liver parenchyma. CT during arterial portography (CTAP), in particular single-level dynamic CTAP, could clearly depict the abnormal dilated portal vein in the lesion and facilitated the diagnosis of this condition. © 2006 Elsevier Ireland Ltd. All rights reserved. Keywords: Focal hepatic lesion; Portal blood supply
1. Introduction Vascular malformations and hemangiomas are endothelial malformations and that may arise in anywhere in the body [1]. Several vascular malformations other than cavernous hemangioma have also been reported in the liver [2–7]. We encountered a case showing localized dilatation of the portal vein mimicking hepatic cavernous hemangioma supplied by the portal vein. In this report, we describe the radiological findings.
2. Case report A 48-year-old man was referred to our hospital for examination of focal hepatic lesions. He did not have any symptoms or signs of chronic liver disease. He did not have a daily ∗
Corresponding author. Tel.: +81 776 23 1111; fax: +81 776 28 8519. E-mail address: [email protected] (S. Miyayama).
1386-6346/$ – see front matter © 2006 Elsevier Ireland Ltd. All rights reserved. doi:10.1016/j.hepres.2006.06.010
drinking habit or a history of steroid administration and hepatic function was normal. Unenhanced CT showed multiple hypodense masses in the right lobe of the liver (Fig. 1a). The diameter of the maximal lesion was 7.5 cm at the posterior superior subsegment and other lesions ranged from 1 to 1.5 cm in diameter. On arterial phase CT, all lesions showed partial enhancement (Fig. 1b), and gradual fill-in and homogenous or inhomogenous enhancement was seen on equilibrium-phase CT (Fig. 1c). The lesions appeared hypointense on T1-weighted MR image and hyperintense similar to that of cerebrospinal fluid on T2-weighted MR image (Fig. 2). Hepatic arteriograms and CTHA did not show any abnormalities corresponding to the hepatic lesions other than a small stain suspected of being a cavernous hemangioma in the right lobe of the liver. On CTAP, all lesions were demonstrated as a hypodense mass containing dilated vessels connected to the portal vein at the periphery or center of the lesions (Fig. 3). Single-level dynamic CTAP was performed targeting the largest 7.5-cm lesion, followed by CTAP. Scanning began 5 s after injection of contrast material, and a 30-s continuous scan with a 2-mm collimation was obtained in
S. Miyayama et al. / Hepatology Research 36 (2006) 70–73
71
Fig. 1. (a) Unenhanced CT shows two hypodense mass lesions 7.5 cm (arrow) and 1 cm (arrowhead) in diameter in the right lobe of the liver. (b) Arterial phase CT shows partial enhancement of both large (arrow) and small lesions (arrowhead). (c) On equilibrium-phase CT, the largest lesion shows inhomogenous enhancement. The small lesion also becomes slightly hyperdense.
a single breath hold without table feed. Images were reconstructed at 0.2-s intervals with a small field of view targeting the lesion. Single-level dynamic CTAP clearly showed that contrast material slowly filled the dilated anomalous poste-
rior superior portal branch and the whole lesion was gradually enhanced (Fig. 4). Three-dimensional CT portography created from CTAP images also showed the dilated anomalous portal branch (Fig. 5).
Fig. 2. T2-weighted MR image demonstrates all lesions as hyperintense (arrow and arrowhead).
Fig. 3. CT during arterial portography (CTAP) shows the dilated portal vein in not only the large hypodense mass but also the small hypodense lesions (arrows).
72
S. Miyayama et al. / Hepatology Research 36 (2006) 70–73
Fig. 6. Histologically, the dilated portal veins and hyperplastic change in the surrounding liver parenchyma are seen. Hepatocytes in the surrounding liver parenchyma does not demonstrate atypia. Portal vein branches (PV) are dilated compared to neighboring hepatic artery (arrow) and bile ducts (arrowheads) (hematoxylin and eosin staining, 100×).
On sonography, the maximal lesion was depicted as an inhomogenous slightly hyperechoic mass with hypoechoic areas but other small lesions were not depicted. Biopsy specimen using an 18-G cutting needle (Max Core; Bard, Covington, GA) was obtained at the periphery of the maximal lesion under sonographic guidance. Histologically, the dilated portal veins and hyperplastic change in the surrounding liver parenchyma were seen. Hepatocytes in the surrounding liver parenchyma did not demonstrate atypia (Fig. 6). Anomalous dilatation of the portal vein was suspected, but the final diagnosis could not be established. None of the lesions showed any change over a 3-year follow-up period. Fig. 4. (a) Single-level dynamic CTAP image obtained 12 s after contrast material injection shows that the dilated portal veins are gradually opacified in both in large (arrow) and small (arrowhead) lesions. (b) Single-level dynamic CTAP image obtained 28 s after contrast material injection shows that the entire mass lesion becomes gradually enhanced.
Fig. 5. Three-dimensional CT portography clearly shows the dilated abnormal portal vein (arrow).
3. Discussion In the present case, hepatic cavernous hemangioma was initially suspected because of delayed enhancement on equilibrium-phase CT and hyperintensity on T2-weighted MR images. However, hepatic angiograms and CTHA did not show any findings corresponding to the lesion. Portal phase images of the superior mesenteric arteriogram showed a dilated portal vein and CTAP demonstrated that the dilated portal vein was located within the lesion. In particular, singlelevel dynamic CTAP could clearly depict gradual opacifying of the abnormal dilated portal vein in the largest lesion over time. The blood flow of the dilated anomalous portal vein was very slow; therefore, CT and MR image findings mimicked hepatic cavernous hemangioma. Several hepatic vascular anomalies, such as intrahepatic portosystemic venous shunt, peliosis hepatis, portal vein aneurysm, and hepatic sinusoidal dilatation, have been reported [2–7]. However, the imaging findings of our case did not correspond to any well-known abnormality. To our knowl-
S. Miyayama et al. / Hepatology Research 36 (2006) 70–73
edge, the literature contains only one case report by Arai et al. [8], which described the same condition as unusual multiple cavernous hemangiomas supplied by the portal vein. They also indicated that their diagnosis was tentative and might be reclassified as another category than hepatic cavernous hemangioma. Hepatic cavernous hemangioma is the most common benign hepatic tumor and has characteristic imaging findings [1]. Peripheral globular enhancement of the lesion on the arterial phase, centripetal enhancement that progresses to uniform filling in the tumor on the venous phase, and persistent enhancement on the delayed phase are seen on dynamic CT or MR images. Hyperintensity similar to that of cerebrospinal fluid on T2-weighted MR images is another characteristic finding. Several atypical hepatic hemangiomas have been reported [9,10]; however, these are usually supplied from the hepatic artery. In addition, contrast material usually enters the lesion from multiple points at the periphery of the lesion. In the present case, however, the contrast material entered the lesion from one point at the periphery or center of the lesion. We speculate that one lesion may be supplied by one dilated abnormal portal branch that the blood flows very slowly; this condition should be called localized portal vein dilatation, not cavernous hemangioma supplied by the portal vein. Hepatic angiosarcoma must also be considered in the differential diagnosis [11,12]. This tumor is the most common malignant mesenchymal tumor of the liver and rarely mimics hepatic cavernous hemangioma [12]. However, this tumor is also depicted on the arterial side on angiography, and usually shows rapid tumor growth [11,12]. Peliosis hepatis is an unusual disorder characterized by multiple blood-filled spaces within the liver. It is divided into two types: parenchymal and phlebectatic [3–6]. In the former, the blood-filled spaces have no endothelial lining and are usually associated with hemorrhagic parenchymal necrosis. In the latter, the spaces are lined with endothelium and are based on aneurysmal dilatation of the central vein. In both types, the abnormal findings are usually seen on the late arterial phase of the hepatic angiogram. Hepatic sinusoidal dilatation is another consideration in the differential diagnosis [7]. It usually occurs in young women with a history of long-term oral contraceptive use. Microscopically, hepatic sinusoidal dilatation is characterized by focal dilatation of the sinusoidal spaces associated with hepatocyte atrophy and necrosis. Hepatic sinusoidal dilatation is heterogeneously hypodense on portal phase CT and slightly hyperintense on T2-weighted MR images.
73
CTAP, in particular single-level dynamic CTAP, shows characteristic findings of this condition; however, CT and MR imaging findings for the present case mimicked those of hepatic cavernous hemangioma. We speculate that this condition may be misdiagnosed as hepatic cavernous hemangioma without performing CTAP, especially in the small lesions, although this condition may be rare. Clinically, however, a clear differential diagnosis between this condition and cavernous hemangioma may not be necessary because both are apparently benign. The portal venous phase CT images may depict the dilated portal vein entering into the lesion and may facilitate diagnosis of this condition; however, we did not obtain these images in this case. In summary, we reported a case of focal hepatic lesions mimicking hepatic cavernous hemangioma supplied by the portal vein. CTAP, in particular single-level dynamic CTAP, was useful to confirm this abnormality. A final diagnosis of this lesion could not be established, but should be categorized in terms of vascular malformations in the future.
References [1] Donnelly LF, Adams DM, Bisset III GS. Vascular malformations and hemangiomas: a practical approach in a multidisciplinary clinic. Am J Roentgenol 2000;174:597–608. [2] Ito K, Matsunaga N, Mitchell DG, et al. Imaging of congenital abnormalities of the portal venous system. Am J Roentgenol 1997;168: 233–7. [3] Pliskin M. Peliosis hepatis. Radiology 1975;114:29–30. [4] Tsukamoto Y, Nakata H, Kimoto T, Noda T, Kuroda Y, Haratake J. CT and angiography of peliosis hepatis. Am J Roentgenol 1984;142:539–40. [5] Maves CK, Caron KH, Bisset III GS, Agarwal R. Splenic and hepatic peliosis: MR findings. Am J Roentgenol 1992;158:75–6. [6] Radin DR, Kanel GC. Peliosis hepatis in a patient with human immunodeficiency virus infection. Am J Roentgenol 1991;156:91–2. [7] Yang DM, Jung DH, Park CH, Kim JE, Choi SJ. Imaging findings of hepatic sinusoidal dilatation. Am J Roentgenol 2004;183:1075–7. [8] Arai K, Matsui O, Kadoya M, et al. Unusual multiple cavernous hemangiomas of the liver supplied by portal blood. Diag Imag Abdomen 1990;10:570–4 (in Japanese). [9] Vilgrain V, Boulos L, Vullierme M-P, Denys A, Terris B, Menu Y. Imaging of atypical hemangiomas of the liver with pathologic correlation. RadioGraphics 2000;20:379–97. [10] Jang HJ, Kim TK, Lim HK, et al. Hepatic hemangioma: atypical appearances on CT, MR imaging, and sonography. Am J Roentgenol 2003;180:135–41. [11] Koyama T, Fletcher JG, Johnson CD, Kuo MS, Notohara K, Burgart LJ. Primary hepatic angiosarcoma: findings at CT and MR imaging. Radiology 2002;222:667–73. [12] Peterson MS, Baron RL, Rankin SC. Hepatic angiosarcoma: findings on multiphasic contrast-enhanced helical CT do not mimic hepatic hemangioma. Am J Roentgenol 2000;175:165–70.