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Intrapleural bronchogenic cyst
European Journal of Radiology 32 (1999) 204 – 207 www.elsevier.nl/locate/ejrad
Case report
Intrapleural bronchogenic cyst Reiji Sugita a,*, Kazuhiro Morimoto b, Fumiaki Yuda c a Department of Radiology, NTT Tohoku Hospital, 2 -29 -1 Yamatomachi, Sendai City, Miyagi Pref. 984 -8560, Japan Department of Surgery, Yamagata Municipal Hospital, 1 -3 -26 Nanokamachi, Yamagata city, Yamagata Pref. 990, Japan c Department of Pathology, Yamagata Municipal Hospital, 1 -3 -26 Nanokamachi, Yamagata City, Yamagata Pref. 990, Japan b
Received 15 June 1998; received in revised form 7 January 1999; accepted 8 January 1999
Abstract We report the first case of a 14-year-old male presenting with intrapleural bronchogenic cyst investigation by CT and MRI. Our findings emphasize the value of the combination of CT and MRI for differential diagnosis of intrapleural tumors. © 1999 Elsevier Science Ireland Ltd. All rights reserved. Keywords: Magnetic resonance imaging; Computed tomography; Thorax; Bronchogenic cyst; Intrapleural tumor
1. Introduction Bronchogenic cysts are unusual developmental anomalies of the bronchopulmonary foregut [1]. They are typically found in the mediastinum around the tracheobronchial tree or in the pulmonary parenchyma [2]. To the best of our knowledge, however, no intrapleural bronchogenic cyst located far from the mediastinum has been found. We report the first case of an intrapleural bronchogenic cyst investigated by CT and MRI.
on T1-weighted spin echo (SE) images and high intensity on T2-weighted fast SE images. The mass showed no enhancement after the intravenous administration of gadolinium–DTPA. The mass was resected by videothoracoscopy. At surgery, the mass was found within the pleural cavity, and did not adhere to the pleura (Fig. 1D). The macroscopic examination revealed a thin-walled cyst containing gel-like material. The microscopic examination demonstrated that the wall of the cyst was lined by respiratory epithelium and contained cartilage, smooth muscle, and glands (Fig. 1E). The histological diagnosis was a bronchogenic cyst.
2. Case report An incidental mass was found in the chest radiograph of a 14-year-old male. CT images demonstrated a homogeneous mass with a CT number of 35 HU (Fig. 1A). The mass was adjacent to the chest wall, with obtuse angles between it and the pleura. On MR images, the mass showed as homogeneous and a markedly low margination between the tumor and the chest wall (Fig. 1B and C). MR signal intensity was intermediate * Corresponding author. Tel. + 81-22-236-5791; fax: +81-022236-5794. E-mail address: [email protected] (R. Sugita)
3. Discussion Bronchogenic cysts result from separation of an aberrant bud from the tracheobronchial tree between the 26th and 40th days of intrauterine life [1]. Most bronchogenic cysts originate in the mediastinum around the tracheobronchial tree or in the pulmonary parenchyma [2]. They can occur in many atypical locations including the neck, intradural space, and below the diaphragm. There are no reports of intrapleural bronchogenic cysts. CT findings of a bronchogenic cyst typically show sharp margination and no contrast enhancement [3].
0720-048X/99/$ - see front matter © 1999 Elsevier Science Ireland Ltd. All rights reserved. PII: S 0 7 2 0 - 0 4 8 X ( 9 9 ) 0 0 0 0 7 - 8
R. Sugita et al. / European Journal of Radiology 32 (1999) 204–207
The CT density can vary from typical water density to high density depending on the cyst’s content. High density represents increased calcium, blood, or protein content within the fluid. The MR appearance is also dependent on the cyst’s content [4 – 6]. If the fluid within a cyst is mainly serous, it will yield a very low signal on T1-weighted images and a very high signal on
205
T2-weighted images. However, the high protein content of the cystic fluid shortens T1, thus resulting in a high signal on T1-weighted images. In our patient, the CT density of the mass was slightly higher than that of water. On the MR image the tumor showed intermediate intensity on T1weighted images and high intensity on T2-weighted
Fig. 1. (A) Intrapleural bronchogenic cyst in a 14-year-old male. The CT scan shows a mass with a CT number of 35 HU. Left side angles of the interface with the chest wall are obtuse (arrows). (B) T1-weighted axial SE (600/15) MR image shows the lesion as an intermediate homogeneous signal mass and a markedly hypointense stripe between the tumor and the chest wall (arrows). (C) T2-weighted axial fast SE (3000/120) MR image showing the lesion as a bright signal. (D) At surgery with videothoracoscopy, the tumor was located in the pleural cavity: T, tumor; C, chest wall; L, lung. (E) Histological specimen shows the thin wall of the cyst lined by ciliated, pseudostratified, columnar, respiratory epithelium (H and E, original magnification × 100).
206
R. Sugita et al. / European Journal of Radiology 32 (1999) 204–207
Fig. 1. (Continued)
images. These findings suggested that the mass contained proteinaceous fluid. When evaluating pleural masses, CT images are helpful, especially with respect to location (i.e. pleural versus parenchymal) [7]. In our case, the CT scans showed that the angles formed between the mass and the pleura were obtuse. Although there is considerable overlap in the appearance of extrapleural, pleural, and parenchymal lesions, this finding suggested an extraparenchymal location. On the other hand, the role of MR imaging for the evaluation of a pleural mass may be limited [7]. In our case, the MR image also showed that the angles
formed between the mass and the pleura were obtuse. This finding suggested that the tumor was extraparenchymal. However, there was a markedly low signal stripe between the mass and the chest wall on the T1-weighted images. This low signal line appeared to represent the cortex of the rib. These findings may lead to the false conclusion that the mass was located in the pulmonary parenchyma away from the chest wall. The differential diagnosis of intrapleural mass includes lipoma, localized fibrous tumor, malignant mesothelioma, and metastatic disease [7]. Lipomas show a uniform fatty signal. Localized fibrous tumors
R. Sugita et al. / European Journal of Radiology 32 (1999) 204–207
207
Fig. 1. (Continued)
often demonstrate lobulated, well-circumscribed, and non-calcified soft tissue masses. Malignant pleural tumors tend to show pleural effusion associated with a markedly thickened, irregular, and often nodular pleura. The differential diagnosis between a bronchogenic cyst and these other entities may be aided by CT and MRI. In conclusion, we present the first reported case of an intrapleural bronchogenic cyst. Our findings emphasize the value of the combination of CT and MRI for differential diagnosis of intrapleural masses. .
References [1] Fraser RG, Pare JAP, Pare PD, Fraser RS, Genereux GP.
[2]
[3]
[4] [5] [6]
[7]
Diagnosis of Disease of the Chest, 3rd edn. Philadelphia, PA: Saunders, 1989:695 – 773. Suen HC, Mathisen DJ, Grillo HC, et al. Surgical management and radiological characteristics of bronchogenic cysts. Ann Thorac Surg 1993;55:476 – 81. Nakata H, Nakayama C, Kimoto T, et al. Computed tomography of mediastinal bronchogenic cysts. J Comput Assist Tomogr 1982;6:733 – 8. Nakata H, Egashira K, Watanabe H, et al. MRI of bronchogenic cysts. J Comput Assist Tomogr 1993;17:267 – 70. Palmer WE, Rivitz SM, Chew FS. Bilateral bronchogenic cysts. Am J Roentgenol 1991;157:950. Marin ML, Romney BM, Franco K, et al. Bronchogenic cyst: a case report emphasizing the role of magnetic resonance imaging. J Thorac Imaging 1991;6:43 – 6. McLoud TC, Flower CD. Imaging the pleura: Sonography, CT, and MR imaging. Am J Roentgenol 1991;156:1145– 53.
Case report
Intrapleural bronchogenic cyst Reiji Sugita a,*, Kazuhiro Morimoto b, Fumiaki Yuda c a Department of Radiology, NTT Tohoku Hospital, 2 -29 -1 Yamatomachi, Sendai City, Miyagi Pref. 984 -8560, Japan Department of Surgery, Yamagata Municipal Hospital, 1 -3 -26 Nanokamachi, Yamagata city, Yamagata Pref. 990, Japan c Department of Pathology, Yamagata Municipal Hospital, 1 -3 -26 Nanokamachi, Yamagata City, Yamagata Pref. 990, Japan b
Received 15 June 1998; received in revised form 7 January 1999; accepted 8 January 1999
Abstract We report the first case of a 14-year-old male presenting with intrapleural bronchogenic cyst investigation by CT and MRI. Our findings emphasize the value of the combination of CT and MRI for differential diagnosis of intrapleural tumors. © 1999 Elsevier Science Ireland Ltd. All rights reserved. Keywords: Magnetic resonance imaging; Computed tomography; Thorax; Bronchogenic cyst; Intrapleural tumor
1. Introduction Bronchogenic cysts are unusual developmental anomalies of the bronchopulmonary foregut [1]. They are typically found in the mediastinum around the tracheobronchial tree or in the pulmonary parenchyma [2]. To the best of our knowledge, however, no intrapleural bronchogenic cyst located far from the mediastinum has been found. We report the first case of an intrapleural bronchogenic cyst investigated by CT and MRI.
on T1-weighted spin echo (SE) images and high intensity on T2-weighted fast SE images. The mass showed no enhancement after the intravenous administration of gadolinium–DTPA. The mass was resected by videothoracoscopy. At surgery, the mass was found within the pleural cavity, and did not adhere to the pleura (Fig. 1D). The macroscopic examination revealed a thin-walled cyst containing gel-like material. The microscopic examination demonstrated that the wall of the cyst was lined by respiratory epithelium and contained cartilage, smooth muscle, and glands (Fig. 1E). The histological diagnosis was a bronchogenic cyst.
2. Case report An incidental mass was found in the chest radiograph of a 14-year-old male. CT images demonstrated a homogeneous mass with a CT number of 35 HU (Fig. 1A). The mass was adjacent to the chest wall, with obtuse angles between it and the pleura. On MR images, the mass showed as homogeneous and a markedly low margination between the tumor and the chest wall (Fig. 1B and C). MR signal intensity was intermediate * Corresponding author. Tel. + 81-22-236-5791; fax: +81-022236-5794. E-mail address: [email protected] (R. Sugita)
3. Discussion Bronchogenic cysts result from separation of an aberrant bud from the tracheobronchial tree between the 26th and 40th days of intrauterine life [1]. Most bronchogenic cysts originate in the mediastinum around the tracheobronchial tree or in the pulmonary parenchyma [2]. They can occur in many atypical locations including the neck, intradural space, and below the diaphragm. There are no reports of intrapleural bronchogenic cysts. CT findings of a bronchogenic cyst typically show sharp margination and no contrast enhancement [3].
0720-048X/99/$ - see front matter © 1999 Elsevier Science Ireland Ltd. All rights reserved. PII: S 0 7 2 0 - 0 4 8 X ( 9 9 ) 0 0 0 0 7 - 8
R. Sugita et al. / European Journal of Radiology 32 (1999) 204–207
The CT density can vary from typical water density to high density depending on the cyst’s content. High density represents increased calcium, blood, or protein content within the fluid. The MR appearance is also dependent on the cyst’s content [4 – 6]. If the fluid within a cyst is mainly serous, it will yield a very low signal on T1-weighted images and a very high signal on
205
T2-weighted images. However, the high protein content of the cystic fluid shortens T1, thus resulting in a high signal on T1-weighted images. In our patient, the CT density of the mass was slightly higher than that of water. On the MR image the tumor showed intermediate intensity on T1weighted images and high intensity on T2-weighted
Fig. 1. (A) Intrapleural bronchogenic cyst in a 14-year-old male. The CT scan shows a mass with a CT number of 35 HU. Left side angles of the interface with the chest wall are obtuse (arrows). (B) T1-weighted axial SE (600/15) MR image shows the lesion as an intermediate homogeneous signal mass and a markedly hypointense stripe between the tumor and the chest wall (arrows). (C) T2-weighted axial fast SE (3000/120) MR image showing the lesion as a bright signal. (D) At surgery with videothoracoscopy, the tumor was located in the pleural cavity: T, tumor; C, chest wall; L, lung. (E) Histological specimen shows the thin wall of the cyst lined by ciliated, pseudostratified, columnar, respiratory epithelium (H and E, original magnification × 100).
206
R. Sugita et al. / European Journal of Radiology 32 (1999) 204–207
Fig. 1. (Continued)
images. These findings suggested that the mass contained proteinaceous fluid. When evaluating pleural masses, CT images are helpful, especially with respect to location (i.e. pleural versus parenchymal) [7]. In our case, the CT scans showed that the angles formed between the mass and the pleura were obtuse. Although there is considerable overlap in the appearance of extrapleural, pleural, and parenchymal lesions, this finding suggested an extraparenchymal location. On the other hand, the role of MR imaging for the evaluation of a pleural mass may be limited [7]. In our case, the MR image also showed that the angles
formed between the mass and the pleura were obtuse. This finding suggested that the tumor was extraparenchymal. However, there was a markedly low signal stripe between the mass and the chest wall on the T1-weighted images. This low signal line appeared to represent the cortex of the rib. These findings may lead to the false conclusion that the mass was located in the pulmonary parenchyma away from the chest wall. The differential diagnosis of intrapleural mass includes lipoma, localized fibrous tumor, malignant mesothelioma, and metastatic disease [7]. Lipomas show a uniform fatty signal. Localized fibrous tumors
R. Sugita et al. / European Journal of Radiology 32 (1999) 204–207
207
Fig. 1. (Continued)
often demonstrate lobulated, well-circumscribed, and non-calcified soft tissue masses. Malignant pleural tumors tend to show pleural effusion associated with a markedly thickened, irregular, and often nodular pleura. The differential diagnosis between a bronchogenic cyst and these other entities may be aided by CT and MRI. In conclusion, we present the first reported case of an intrapleural bronchogenic cyst. Our findings emphasize the value of the combination of CT and MRI for differential diagnosis of intrapleural masses. .
References [1] Fraser RG, Pare JAP, Pare PD, Fraser RS, Genereux GP.
[2]
[3]
[4] [5] [6]
[7]
Diagnosis of Disease of the Chest, 3rd edn. Philadelphia, PA: Saunders, 1989:695 – 773. Suen HC, Mathisen DJ, Grillo HC, et al. Surgical management and radiological characteristics of bronchogenic cysts. Ann Thorac Surg 1993;55:476 – 81. Nakata H, Nakayama C, Kimoto T, et al. Computed tomography of mediastinal bronchogenic cysts. J Comput Assist Tomogr 1982;6:733 – 8. Nakata H, Egashira K, Watanabe H, et al. MRI of bronchogenic cysts. J Comput Assist Tomogr 1993;17:267 – 70. Palmer WE, Rivitz SM, Chew FS. Bilateral bronchogenic cysts. Am J Roentgenol 1991;157:950. Marin ML, Romney BM, Franco K, et al. Bronchogenic cyst: a case report emphasizing the role of magnetic resonance imaging. J Thorac Imaging 1991;6:43 – 6. McLoud TC, Flower CD. Imaging the pleura: Sonography, CT, and MR imaging. Am J Roentgenol 1991;156:1145– 53.