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Mediastinal Castleman disease: heterogeneous enhancement with filling-in pattern on dynamic CT and MRI
European Journal of Radiology Extra 52 (2004) 103–105
Mediastinal Castleman disease: heterogeneous enhancement with filling-in pattern on dynamic CT and MRI Young Jin Kim, Byoung Wook Choi∗ , Jae Seung Seo, Kyu Ok Choe Department of Diagnostic Radiology, College of Medicine, Yonsei University, 134 Shinchon-dong, Seodaemun-gu, Seoul 120752, Republic of Korea Received 17 May 2004; received in revised form 17 September 2004; accepted 20 September 2004
Abstract Homogeneously intense contrast enhancement is considered to be the CT finding characteristic of unicentric thoracic Castleman diseases. We report a case of mediastinal Castleman disease presenting a huge tumor with heterogeneous enhancement accompanied with a filling-in pattern enhancement on dynamic CT and magnetic resonance imaging (MRI). © 2004 Elsevier Ireland Ltd. All rights reserved. Keywords: Castleman disease; Mediastinal tumor; MRI; CT
1. Introduction Castleman disease is a rare benign lymphoproliferative disease of unclear etiology and pathogenesis. Moderate to striking uniform contrast enhancement has been reported as a typical CT finding, which might be helpful to differentiate it from other mediastinal masses, such as a lymphoma [1–3]. However, we noticed that the present case showed an unusually large sized tumor, which had mixed components of early enhancement and unusual centripetal delayed enhancement and strikingly engorged vessels around its mass on dynamic CT and magnetic resonance imaging (MRI).
2. Case report A 26-year-old healthy woman presented a mediastinal mass on a chest radiograph during a routine health check-up. She underwent a CT scan (Fig. 1A and B). Our routine chest CT protocol is composed of a spiral scan taken on the arterial phase and a thin-section scan taken on the delayed phase. A large mass was found on the anterior mediastinum, which ∗
Tel.: +82 2361 5837; fax: +82 2393 3035. E-mail address: [email protected] (B.W. Choi).
1571-4675/$ – see front matter © 2004 Elsevier Ireland Ltd. All rights reserved. doi:10.1016/j.ejrex.2004.09.009
was relatively well encapsulated and slightly lobulated. The mass extended from the prevascular space to the right paracardiac area. Within the mass, linear and spotted calcifications were noted. Multiple dilated and tortuous vascular structures and multiple enlarged lymph nodes were noted around the mass. Heterogeneous and strong enhancement was seen during the arterial phase, but the poorly enhanced central area observed in the arterial phase showed delayed enhancement. We considered this mass as a tumor of vascular origin such as a hemangioma or an angiosarcoma. Subsequently, the patient underwent MRI to better characterize the mass with a dynamic scan and evaluate the extension of the mass. T1-weighted images showed homogenous and slightly higher signal intensities than that of the chest wall muscle. T2-weighted images demonstrated a heterogeneous bright signal intensity on the right portion of the mass and a relatively hypointense signal intensity on the left portion with multiple signal void structures, suggesting peripheral vessels (Fig. 1C and D). No fat component within the mass was demonstrated in the T1-weighted images with or without fat suppression. A dynamic enhancement study showed early peripheral enhancement in the superior portion of the mass with a delayed fill-in pattern and ultimate homogenous enhancement (Fig. 1E). The inferior portion of the mass showed early enhancement and delayed washout.
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Y.J. Kim et al. / European Journal of Radiology Extra 52 (2004) 103–105
Fig. 1. A 26-year-old woman without remarkable medical history: (A) contrast-enhanced chest CT scan shows a well-defined, heterogeneously enhancing mass in the arterial phase. A poorly enhanced area was noted within the central portion of the mass. (B) Thin-section CT in the delayed phase demonstrates delayed enhancement of the poorly enhanced portion. Spotted calcification is noted within the mass. (C–D) Double inversion recovery T1-weighted image (C) shows homogenous and a slightly higher signal intensity than that of the chest wall muscle. Double inversion recovery T2-weighted image (D) shows a heterogeneous mass and peripheral tortuous signal void structures, suggesting blood vessels. (E) Dynamic MR imaging demonstrates early peripheral and a delayed fill-in pattern enhancement on the upper part of the mass. The tubular structure traversing the mass (arrow) is a ghost artifact due to the right pulmonary artery. Dynamic images were obtained before and 27, 54, 81 s and 15 min after an intravenous injection of gadolinium. (F) Photomicrograph of the histopathologic specimen shows central hyalinized capillaries and typical concentric layering of perifollicular lymphocytes (onion-skin appearance). Hematoxylin–eosin, 200×.
One month later, an excision was performed without complication. The specimen consisted of a lump of relatively well-circumscribed firm tissue. Upon sectioning, the cut surface showed a homogeneously pale tan to yellow color and was solid and firm. Thick fibrous bands, multifocal hemorrhage and calcification were noted within the mass. The surrounding fat tissue contained sev-
eral enlarged lymph nodes. Microscopic sections of the mass showed numerous small follicle-like structures with hyalinized capillaries. Perifollicular concentric layering of small lymphocytes, so called “onion-skin appearance”, was noted on high-power magnification. The pathologic diagnosis was Castleman disease of the hyaline-vascular type.
Y.J. Kim et al. / European Journal of Radiology Extra 52 (2004) 103–105
3. Discussion Castleman disease, also known as angiofollicular hyperplasia or giant lymph node hyperplasia, is a rare disorder of lymphoid tissue. This disease may occur anywhere along the lymphatic chain but it is most commonly found as a solitary mass in the mediastinum [1,2]. Two distinct histologic patterns of Castleman disease have been described, including the hyaline-vascular type, accounting for 90% of cases, and the remainder of cases as the plasma cell type, which is often associated with constitutional symptoms [4]. Three patterns have been reported on CT or MRI, including a solitary noninvasive mass (50%), a dominant infiltrative mass with associated lymphadenopathy (40%), like the present case, and a matted lymphadenopathy without a dominant mass (10%) [5]. In Castleman disease, CT with contrast material usually shows a dense uniform enhancement. Dynamic CT demonstrates early rapid enhancement and washout in the delayed phase, which are considered as typical imaging characteristics that help to differentiate this disease from other mediastinal tumors, furthermore, peripheral hypervascularity is a characteristic finding on power Doppler ultrasonography [2,5,6]. A punctate or arborizing pattern of calcification may be seen [6]. Some recent studies have reported a considerable number of cases showing heterogeneous attenuation. Meador and McLarney [3] reported that tumors greater than 5 cm in diameter generally demonstrate heterogeneous enhancement. In several studies, a focal low attenuation area within the mass showing delayed enhancement on dynamic CT or MRI, was pathologically proven to be central stellate fibrosis interspersed within the mass [6,7]. In the present case, dynamic CT and MR images showed a filling-in pattern enhancement on a part of the mass and early enhancement and delayed washout on the remainder. To our knowledge, there have been few reports on Castleman disease showing a centripetal enhancement pattern. The observed early peripheral enhancement and delayed filling-in
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may have been due to peripheral feeding arteries, the large size of the tumor, or the internal fibrotic area, resembling a hepatic hemangioma. An MRI study has been reported to be useful for the evaluation of peripheral or tumoral hypervascularity and the relationship with adjacent vascular structures, because vascular structures appear signal void with high contrast to the mass [8]. In the present case, double inversion recovery, so called ‘black blood imaging’ with T1- or T2-weighted images, excellently demonstrated peripheral dilated and tortuous vascular structures. In summary, Castleman disease may show a heterogeneous enhancement pattern; it shows not only early enhancement followed by delayed washout but also a centripetal form. Early peripheral enhancement is well demonstrated by dynamic CT or MRI, whereas peripheral hypervascularity is well demonstrated with double inversion recovery T1- or T2weighted images. References [1] McCarthy MJ, Vukelja SJ, Banks PM, Weiss RB. Angiofollicular lymph node hyperplasia (Castleman disease). Cancer Treat Rev 1995;21:291–310. [2] Moon WK, Im JG, Kim JS, et al. Mediastinal Castleman disease: CT findings. J Comput Assist Tomogr 1994;18:43–6. [3] Meador TL, McLarney JK. CT features of Castleman disease of the abdomen and pelvis. AJR 2001;175:115–8. [4] Keller AR, Hochholzer L, Castleman B. Hyaline vascular and plasmacell types of giant lymph node hyperplasia of the mediastinum and other locations. Cancer 1972;29:670–81. [5] McAdams HP, Rosado-de-Christenson M, Fishback NF, Templeton PA. Castleman disease of the thorax: radiologic features with clinical and histopathologic correlation. Radiology 1998;209:221–8. [6] Kim TJ, Han JK, Kim YH, Kim TK, Choi BI. Castleman disease of the abdomen: imaging spectrum and clinicopathologic correlations. J Comput Assist Tomogr 2001;25:207–14. [7] Ota T, Mitsuyoshi A, Zaima M, et al. Visualization of central stellate fibrosis in hyaline vascular type Castleman disease. Brit J Radiol 1997;70:1060–2. [8] Moon WK, Im JG, Han MC. Castleman disease of the mediastinum: MR imaging features. Clin Radiol 1994;49:466–7.
Mediastinal Castleman disease: heterogeneous enhancement with filling-in pattern on dynamic CT and MRI Young Jin Kim, Byoung Wook Choi∗ , Jae Seung Seo, Kyu Ok Choe Department of Diagnostic Radiology, College of Medicine, Yonsei University, 134 Shinchon-dong, Seodaemun-gu, Seoul 120752, Republic of Korea Received 17 May 2004; received in revised form 17 September 2004; accepted 20 September 2004
Abstract Homogeneously intense contrast enhancement is considered to be the CT finding characteristic of unicentric thoracic Castleman diseases. We report a case of mediastinal Castleman disease presenting a huge tumor with heterogeneous enhancement accompanied with a filling-in pattern enhancement on dynamic CT and magnetic resonance imaging (MRI). © 2004 Elsevier Ireland Ltd. All rights reserved. Keywords: Castleman disease; Mediastinal tumor; MRI; CT
1. Introduction Castleman disease is a rare benign lymphoproliferative disease of unclear etiology and pathogenesis. Moderate to striking uniform contrast enhancement has been reported as a typical CT finding, which might be helpful to differentiate it from other mediastinal masses, such as a lymphoma [1–3]. However, we noticed that the present case showed an unusually large sized tumor, which had mixed components of early enhancement and unusual centripetal delayed enhancement and strikingly engorged vessels around its mass on dynamic CT and magnetic resonance imaging (MRI).
2. Case report A 26-year-old healthy woman presented a mediastinal mass on a chest radiograph during a routine health check-up. She underwent a CT scan (Fig. 1A and B). Our routine chest CT protocol is composed of a spiral scan taken on the arterial phase and a thin-section scan taken on the delayed phase. A large mass was found on the anterior mediastinum, which ∗
Tel.: +82 2361 5837; fax: +82 2393 3035. E-mail address: [email protected] (B.W. Choi).
1571-4675/$ – see front matter © 2004 Elsevier Ireland Ltd. All rights reserved. doi:10.1016/j.ejrex.2004.09.009
was relatively well encapsulated and slightly lobulated. The mass extended from the prevascular space to the right paracardiac area. Within the mass, linear and spotted calcifications were noted. Multiple dilated and tortuous vascular structures and multiple enlarged lymph nodes were noted around the mass. Heterogeneous and strong enhancement was seen during the arterial phase, but the poorly enhanced central area observed in the arterial phase showed delayed enhancement. We considered this mass as a tumor of vascular origin such as a hemangioma or an angiosarcoma. Subsequently, the patient underwent MRI to better characterize the mass with a dynamic scan and evaluate the extension of the mass. T1-weighted images showed homogenous and slightly higher signal intensities than that of the chest wall muscle. T2-weighted images demonstrated a heterogeneous bright signal intensity on the right portion of the mass and a relatively hypointense signal intensity on the left portion with multiple signal void structures, suggesting peripheral vessels (Fig. 1C and D). No fat component within the mass was demonstrated in the T1-weighted images with or without fat suppression. A dynamic enhancement study showed early peripheral enhancement in the superior portion of the mass with a delayed fill-in pattern and ultimate homogenous enhancement (Fig. 1E). The inferior portion of the mass showed early enhancement and delayed washout.
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Y.J. Kim et al. / European Journal of Radiology Extra 52 (2004) 103–105
Fig. 1. A 26-year-old woman without remarkable medical history: (A) contrast-enhanced chest CT scan shows a well-defined, heterogeneously enhancing mass in the arterial phase. A poorly enhanced area was noted within the central portion of the mass. (B) Thin-section CT in the delayed phase demonstrates delayed enhancement of the poorly enhanced portion. Spotted calcification is noted within the mass. (C–D) Double inversion recovery T1-weighted image (C) shows homogenous and a slightly higher signal intensity than that of the chest wall muscle. Double inversion recovery T2-weighted image (D) shows a heterogeneous mass and peripheral tortuous signal void structures, suggesting blood vessels. (E) Dynamic MR imaging demonstrates early peripheral and a delayed fill-in pattern enhancement on the upper part of the mass. The tubular structure traversing the mass (arrow) is a ghost artifact due to the right pulmonary artery. Dynamic images were obtained before and 27, 54, 81 s and 15 min after an intravenous injection of gadolinium. (F) Photomicrograph of the histopathologic specimen shows central hyalinized capillaries and typical concentric layering of perifollicular lymphocytes (onion-skin appearance). Hematoxylin–eosin, 200×.
One month later, an excision was performed without complication. The specimen consisted of a lump of relatively well-circumscribed firm tissue. Upon sectioning, the cut surface showed a homogeneously pale tan to yellow color and was solid and firm. Thick fibrous bands, multifocal hemorrhage and calcification were noted within the mass. The surrounding fat tissue contained sev-
eral enlarged lymph nodes. Microscopic sections of the mass showed numerous small follicle-like structures with hyalinized capillaries. Perifollicular concentric layering of small lymphocytes, so called “onion-skin appearance”, was noted on high-power magnification. The pathologic diagnosis was Castleman disease of the hyaline-vascular type.
Y.J. Kim et al. / European Journal of Radiology Extra 52 (2004) 103–105
3. Discussion Castleman disease, also known as angiofollicular hyperplasia or giant lymph node hyperplasia, is a rare disorder of lymphoid tissue. This disease may occur anywhere along the lymphatic chain but it is most commonly found as a solitary mass in the mediastinum [1,2]. Two distinct histologic patterns of Castleman disease have been described, including the hyaline-vascular type, accounting for 90% of cases, and the remainder of cases as the plasma cell type, which is often associated with constitutional symptoms [4]. Three patterns have been reported on CT or MRI, including a solitary noninvasive mass (50%), a dominant infiltrative mass with associated lymphadenopathy (40%), like the present case, and a matted lymphadenopathy without a dominant mass (10%) [5]. In Castleman disease, CT with contrast material usually shows a dense uniform enhancement. Dynamic CT demonstrates early rapid enhancement and washout in the delayed phase, which are considered as typical imaging characteristics that help to differentiate this disease from other mediastinal tumors, furthermore, peripheral hypervascularity is a characteristic finding on power Doppler ultrasonography [2,5,6]. A punctate or arborizing pattern of calcification may be seen [6]. Some recent studies have reported a considerable number of cases showing heterogeneous attenuation. Meador and McLarney [3] reported that tumors greater than 5 cm in diameter generally demonstrate heterogeneous enhancement. In several studies, a focal low attenuation area within the mass showing delayed enhancement on dynamic CT or MRI, was pathologically proven to be central stellate fibrosis interspersed within the mass [6,7]. In the present case, dynamic CT and MR images showed a filling-in pattern enhancement on a part of the mass and early enhancement and delayed washout on the remainder. To our knowledge, there have been few reports on Castleman disease showing a centripetal enhancement pattern. The observed early peripheral enhancement and delayed filling-in
105
may have been due to peripheral feeding arteries, the large size of the tumor, or the internal fibrotic area, resembling a hepatic hemangioma. An MRI study has been reported to be useful for the evaluation of peripheral or tumoral hypervascularity and the relationship with adjacent vascular structures, because vascular structures appear signal void with high contrast to the mass [8]. In the present case, double inversion recovery, so called ‘black blood imaging’ with T1- or T2-weighted images, excellently demonstrated peripheral dilated and tortuous vascular structures. In summary, Castleman disease may show a heterogeneous enhancement pattern; it shows not only early enhancement followed by delayed washout but also a centripetal form. Early peripheral enhancement is well demonstrated by dynamic CT or MRI, whereas peripheral hypervascularity is well demonstrated with double inversion recovery T1- or T2weighted images. References [1] McCarthy MJ, Vukelja SJ, Banks PM, Weiss RB. Angiofollicular lymph node hyperplasia (Castleman disease). Cancer Treat Rev 1995;21:291–310. [2] Moon WK, Im JG, Kim JS, et al. Mediastinal Castleman disease: CT findings. J Comput Assist Tomogr 1994;18:43–6. [3] Meador TL, McLarney JK. CT features of Castleman disease of the abdomen and pelvis. AJR 2001;175:115–8. [4] Keller AR, Hochholzer L, Castleman B. Hyaline vascular and plasmacell types of giant lymph node hyperplasia of the mediastinum and other locations. Cancer 1972;29:670–81. [5] McAdams HP, Rosado-de-Christenson M, Fishback NF, Templeton PA. Castleman disease of the thorax: radiologic features with clinical and histopathologic correlation. Radiology 1998;209:221–8. [6] Kim TJ, Han JK, Kim YH, Kim TK, Choi BI. Castleman disease of the abdomen: imaging spectrum and clinicopathologic correlations. J Comput Assist Tomogr 2001;25:207–14. [7] Ota T, Mitsuyoshi A, Zaima M, et al. Visualization of central stellate fibrosis in hyaline vascular type Castleman disease. Brit J Radiol 1997;70:1060–2. [8] Moon WK, Im JG, Han MC. Castleman disease of the mediastinum: MR imaging features. Clin Radiol 1994;49:466–7.