Clinical Radiology (1992) 45, 271-272
Ultrasonic and Computed Tomographic Appearances of Paraganglioma Simulating Pancreatic Mass S. R. M A L T H O U S E ,
L_ R O B I N S O N
a n d S. C_ R A N K I N
Department of Diagnostic Radiology, Guy's Hospital, London W e report two cases of paraganglioma in which the tumour was situated adjacent to the head of the pancreas simulating a pancreatic mass lesion. The absence of biliary or pancreatic duct dilatation on ultrasound in the presence of a large mass suggested a retroperitoneal tumour rather than a pancreatic adenocarcinoma. Functional activity in these tumours is common and should be excluded before biopsy. Malthouse, S.R., R o b i n s o n , L. & Rankin, S.C. (1992)_
Clinical Radiology 45, 2 7 1 - 2 7 2 . U l t r a s o n i c a n d C o m p u t e d T o m o g r a p h i c A p p e a r a n c e s o f Paraganglioma Simulating Pancreatic Mass
P a r a g a n g l i o m a s or e x t r a - a d r e n a l p h a e o c h r o m o c y t o m a s are r a r e t u m o u r s a f f e c t i n g a b o u t 1 / 2 0 0 0 0 0 0 o f the p o p u l a t i o n . T h e y o r i g i n a t e in p a r a g a n g l i o n cells l y i n g a d j a c e n t to t h e g a n g l i a a n d p l e x u s e s o f the a u t o n o m i c n e r v o u s system. T u m o u r s m a y arise a n y w h e r e , for e x a m ple f r o m the c a r o t i d b o d y to t h e u r i n a r y b l a d d e r , b u t m o s t arise fi-om the s y m p a t h e t i c c h a i n b e t w e e n the origin o f the renal arteries a n d the a o r t i c b i f u r c a t i o n . T h e r e is an a s s o c i a t i o n o f p a r a g a n g l i o m a s with V o n H i p p e l L i n d a u disease, n e u r o f i b r o m a t o s i s a n d m u l t i p l e e n d o c r i n e n e o plasia types I I a a n d I I b ( L a n d s b e r g a n d Y o u n g , 1991). P a t i e n t s m a y p r e s e n t w i t h a mass, local s y m p t o m s c a u s e d by t h e mass, o r if the t u m o u r is f u n c t i o n a l l y active, w i t h s y m p t o m s d u e to excess h o r m o n e p r o d u c t i o n . T u m o u r s most, c o m m o n l y secrete c a t e c h o l a m i n e s g i v i n g rise to h y p e r t e n s i o n , a n x i e t y , p a l p i t a t i o n and t r e m o r . A r e c e n t s t u d y o f 28 cases o f p a r a g a n g l i o m a ( H a y e s et al., 1990) f o u n d t h a t 24 p a t i e n t s ( 8 6 % ) h a d h y p e r t e n s i o n . S e r u m c a t e c h o l a m i n e s w e r e e l e v a t e d in all 18 h y p e r t e n sive p a t i e n t s in w h o m d a t a w e r e a v a i l a b l e . In a n o t h e r s t u d y ( L a n e et al., 1989) 11 o f 12 cases ( 9 1 % ) o f p a r a g a n g l i o m a h a d e v i d e n c e o f c a t e c h o l a m i n e excess, t h o u g h the f r e q u e n c y o f h y p e r t e n s i o n was n o t r e p o r t e d .
(a)
CASE REPORTS
Case I. A 45-year-old female patient developed anaemia and was referred for a pelvic ultrasound for suspected uterine fibroids. Fibroids were confirmed and additionally a large mass was noted near to the head of the pancreas (Fig. la). The mass was well defined, had an echolucent centre and measured 8 cm in diameter. The bile ducts were not dilatated. Computed tomography (CT) was subsequently performed which showed a similar appearance (Fig. l b). The possibility of a retroperitoheal tumour was raised. The patient was not hypertensive and the vanillylmandclic acid (VMA) level in the urine was not measured. She subsequently underwent laparatomy, the mass was totally removed and shown to be a paraganglioma. Five years on she remains well. Case 2. A 58-year-old man was referred to surgical out-patients with st 4 month history of a right hypochondrial ache associated with anorexia and nausea. His past medical history included total correction of Fallot's tetralogy at the age of 43, removal of a left carotid body turnout when 41 and a right carotid body tumour at 56 years of age. Since his cardiac surgery he had suffered with intermittent supraventricular tachycardias. There was no history of hypertension.
Correspondence to: S. R. Malthouse, Department of Diagnostic Radiology, Guy's Hospital, St. Thomas Street, London SEI 9RT.
(b) Fig. 1 (a) Ultrasound, Transverse section through the upper abdomen showing the mass with echolucent centre situated between the splenic vein and inferior vena cava. (b) CT. Transverse section through the body of the pancreas after contrast. The mass is again demonstrated. Note the lack of biliary or pancreatm duct dilatation.
272
CLINICAL RADIOLOGY
DISCUSSION
(a)
(b) Fig. 2 (a) Ultrasound. Longitudinal section through the upper abdomen demonstrating an 8 cm mass with an echolucent centre. There is an echogenic focus with acoustic shadowing consistent with calcification. (b) CT. Transverse section through the upper abdomen. This demonstrates a large mass with a low density centre and small focus of calcification displacing the pancreatic body anteriorly.
The clinical diagnosis was cholecystitis or biliary colic and he was referred for US. The US examination confirmed gall-stones but also revealed an 8 Cln diameter well defined mass with an echolucent centre lying close to the head of the pancreas (Fig. 2a). No dilatation of the c o m m o n duct or pancreatic duct was seen. D u e to these appearances, a t u m o u r of neuroendocrine origin was considered. On CT the mass appeared to be displacing the pancreas anteriorly, further supporting the provisional diagnosis of a retroperitoneal t u m o u r (Fig. 2b). USguided biopsy confirmed a paraganglioma. The biopsy was complicated by a vasovagal attack but subsequent VMAs were normal. The t u m o u r was resected without incident, the gall-bladder being removed at the same time. Histology confirmed complete removal of a paraganglioma.
In both of these cases, the discovery of the mass was an incidental finding and neither patient had hypertension or symptoms attributable to hormone production. Both masses were large (8 cm diameter in both cases) and-well defined with central areas of low attenuation. Calcification was present in one case. These findings are in agreement with a recent study of 28 cases using CT where average size was 8.6 cm, 70% were well defined, 39% had central low attenuation and 15% had punctate calcification (Hayes et al., 1990). There is a dearth of literature on the US appearance of paragangliomas. The absence of biliary or pancreatic duct dilatation on US and the presence of central low attenuation suggest a diagnosis other than pancreatic carcinoma. In a study of pancreatic carcinoma using dynamic CT by Freeny (1988), 88% of patients with tumour in the pancreatic head had duct dilatation and only 18 of 153 cases (12%) had central areas of low attenuation consistent with necrosis. M a n y other retroperitoneal neoplasms including leiomyosarcoma, liposarcoma and malignant fibrous histiocytoma could give similar appearances though the absence of fat argues against liposarcoma (Lane et al., 1989). The US appearances might have been caused by a very large necrotic lymph node mass or a phlegmon of acute pancreatitis, although the clinical findings did not support these diagnoses. The majority of paragangliomas are functionally active. The mortality rate for surgery on unsuspected cases o f p h a e o c h r o m o c y t o m a is nearly 50%. The risk of a hypertensive crisis from biopsy or surgical excision is reduced by alpha and betablockade though the risk of haemorrhage may be unaffected (McCorkell and Niles, 1985)_ VMAs were not measured in Case 1 and only subsequent to biopsy in Case 2. Acknowledgements. We are grateful to Mrs H. Winskeli and Dr J. Bingham for their help and advice.
REFERENCES Freeny, PC, Marks, W M , Ryan, JA & Traverso, LW (1988). Pancreatic ductal adenocarcinoma: diagnosis and staging with dynamic CT. Radiology, 166, 125 133. Hayes, WS, Davidson, AJ, Grimley, PM & Hartman, DS (1990). Extraadrenal retroperitoneal paraganglioma: clinical, pathologic and CT findings. American Journal of Roentgenology, 155, 1247 1250. Landsberg, L & Young, JB (1991). Harrison's Principles of Internal Medic#w, eds. Wilson, JD, Braunwald, E, lsselbacher, KJ, Petersdoff, RG, Martin, JB, Fauci, AS et al. 12th edn, pp. 1735-1739. McGraw-Hill, New York. Lane, RH, Stephens, D H & Reiman, H M (1989). Primary retroperitoneal neoplasms: CT findings in 90 cases with clinical and pathologic correlation. American Journal of Roentgenology, 152, 83 89. McCorkell, SJ & Niles, N L (1985). Fine-needle aspiration of catecholamine-producing adrenal masses: a possibly fatal mistake. American Journal of Roentgenology, 145, 113 114.
Ultrasonic and Computed Tomographic Appearances of Paraganglioma Simulating Pancreatic Mass S. R. M A L T H O U S E ,
L_ R O B I N S O N
a n d S. C_ R A N K I N
Department of Diagnostic Radiology, Guy's Hospital, London W e report two cases of paraganglioma in which the tumour was situated adjacent to the head of the pancreas simulating a pancreatic mass lesion. The absence of biliary or pancreatic duct dilatation on ultrasound in the presence of a large mass suggested a retroperitoneal tumour rather than a pancreatic adenocarcinoma. Functional activity in these tumours is common and should be excluded before biopsy. Malthouse, S.R., R o b i n s o n , L. & Rankin, S.C. (1992)_
Clinical Radiology 45, 2 7 1 - 2 7 2 . U l t r a s o n i c a n d C o m p u t e d T o m o g r a p h i c A p p e a r a n c e s o f Paraganglioma Simulating Pancreatic Mass
P a r a g a n g l i o m a s or e x t r a - a d r e n a l p h a e o c h r o m o c y t o m a s are r a r e t u m o u r s a f f e c t i n g a b o u t 1 / 2 0 0 0 0 0 0 o f the p o p u l a t i o n . T h e y o r i g i n a t e in p a r a g a n g l i o n cells l y i n g a d j a c e n t to t h e g a n g l i a a n d p l e x u s e s o f the a u t o n o m i c n e r v o u s system. T u m o u r s m a y arise a n y w h e r e , for e x a m ple f r o m the c a r o t i d b o d y to t h e u r i n a r y b l a d d e r , b u t m o s t arise fi-om the s y m p a t h e t i c c h a i n b e t w e e n the origin o f the renal arteries a n d the a o r t i c b i f u r c a t i o n . T h e r e is an a s s o c i a t i o n o f p a r a g a n g l i o m a s with V o n H i p p e l L i n d a u disease, n e u r o f i b r o m a t o s i s a n d m u l t i p l e e n d o c r i n e n e o plasia types I I a a n d I I b ( L a n d s b e r g a n d Y o u n g , 1991). P a t i e n t s m a y p r e s e n t w i t h a mass, local s y m p t o m s c a u s e d by t h e mass, o r if the t u m o u r is f u n c t i o n a l l y active, w i t h s y m p t o m s d u e to excess h o r m o n e p r o d u c t i o n . T u m o u r s most, c o m m o n l y secrete c a t e c h o l a m i n e s g i v i n g rise to h y p e r t e n s i o n , a n x i e t y , p a l p i t a t i o n and t r e m o r . A r e c e n t s t u d y o f 28 cases o f p a r a g a n g l i o m a ( H a y e s et al., 1990) f o u n d t h a t 24 p a t i e n t s ( 8 6 % ) h a d h y p e r t e n s i o n . S e r u m c a t e c h o l a m i n e s w e r e e l e v a t e d in all 18 h y p e r t e n sive p a t i e n t s in w h o m d a t a w e r e a v a i l a b l e . In a n o t h e r s t u d y ( L a n e et al., 1989) 11 o f 12 cases ( 9 1 % ) o f p a r a g a n g l i o m a h a d e v i d e n c e o f c a t e c h o l a m i n e excess, t h o u g h the f r e q u e n c y o f h y p e r t e n s i o n was n o t r e p o r t e d .
(a)
CASE REPORTS
Case I. A 45-year-old female patient developed anaemia and was referred for a pelvic ultrasound for suspected uterine fibroids. Fibroids were confirmed and additionally a large mass was noted near to the head of the pancreas (Fig. la). The mass was well defined, had an echolucent centre and measured 8 cm in diameter. The bile ducts were not dilatated. Computed tomography (CT) was subsequently performed which showed a similar appearance (Fig. l b). The possibility of a retroperitoheal tumour was raised. The patient was not hypertensive and the vanillylmandclic acid (VMA) level in the urine was not measured. She subsequently underwent laparatomy, the mass was totally removed and shown to be a paraganglioma. Five years on she remains well. Case 2. A 58-year-old man was referred to surgical out-patients with st 4 month history of a right hypochondrial ache associated with anorexia and nausea. His past medical history included total correction of Fallot's tetralogy at the age of 43, removal of a left carotid body turnout when 41 and a right carotid body tumour at 56 years of age. Since his cardiac surgery he had suffered with intermittent supraventricular tachycardias. There was no history of hypertension.
Correspondence to: S. R. Malthouse, Department of Diagnostic Radiology, Guy's Hospital, St. Thomas Street, London SEI 9RT.
(b) Fig. 1 (a) Ultrasound, Transverse section through the upper abdomen showing the mass with echolucent centre situated between the splenic vein and inferior vena cava. (b) CT. Transverse section through the body of the pancreas after contrast. The mass is again demonstrated. Note the lack of biliary or pancreatm duct dilatation.
272
CLINICAL RADIOLOGY
DISCUSSION
(a)
(b) Fig. 2 (a) Ultrasound. Longitudinal section through the upper abdomen demonstrating an 8 cm mass with an echolucent centre. There is an echogenic focus with acoustic shadowing consistent with calcification. (b) CT. Transverse section through the upper abdomen. This demonstrates a large mass with a low density centre and small focus of calcification displacing the pancreatic body anteriorly.
The clinical diagnosis was cholecystitis or biliary colic and he was referred for US. The US examination confirmed gall-stones but also revealed an 8 Cln diameter well defined mass with an echolucent centre lying close to the head of the pancreas (Fig. 2a). No dilatation of the c o m m o n duct or pancreatic duct was seen. D u e to these appearances, a t u m o u r of neuroendocrine origin was considered. On CT the mass appeared to be displacing the pancreas anteriorly, further supporting the provisional diagnosis of a retroperitoneal t u m o u r (Fig. 2b). USguided biopsy confirmed a paraganglioma. The biopsy was complicated by a vasovagal attack but subsequent VMAs were normal. The t u m o u r was resected without incident, the gall-bladder being removed at the same time. Histology confirmed complete removal of a paraganglioma.
In both of these cases, the discovery of the mass was an incidental finding and neither patient had hypertension or symptoms attributable to hormone production. Both masses were large (8 cm diameter in both cases) and-well defined with central areas of low attenuation. Calcification was present in one case. These findings are in agreement with a recent study of 28 cases using CT where average size was 8.6 cm, 70% were well defined, 39% had central low attenuation and 15% had punctate calcification (Hayes et al., 1990). There is a dearth of literature on the US appearance of paragangliomas. The absence of biliary or pancreatic duct dilatation on US and the presence of central low attenuation suggest a diagnosis other than pancreatic carcinoma. In a study of pancreatic carcinoma using dynamic CT by Freeny (1988), 88% of patients with tumour in the pancreatic head had duct dilatation and only 18 of 153 cases (12%) had central areas of low attenuation consistent with necrosis. M a n y other retroperitoneal neoplasms including leiomyosarcoma, liposarcoma and malignant fibrous histiocytoma could give similar appearances though the absence of fat argues against liposarcoma (Lane et al., 1989). The US appearances might have been caused by a very large necrotic lymph node mass or a phlegmon of acute pancreatitis, although the clinical findings did not support these diagnoses. The majority of paragangliomas are functionally active. The mortality rate for surgery on unsuspected cases o f p h a e o c h r o m o c y t o m a is nearly 50%. The risk of a hypertensive crisis from biopsy or surgical excision is reduced by alpha and betablockade though the risk of haemorrhage may be unaffected (McCorkell and Niles, 1985)_ VMAs were not measured in Case 1 and only subsequent to biopsy in Case 2. Acknowledgements. We are grateful to Mrs H. Winskeli and Dr J. Bingham for their help and advice.
REFERENCES Freeny, PC, Marks, W M , Ryan, JA & Traverso, LW (1988). Pancreatic ductal adenocarcinoma: diagnosis and staging with dynamic CT. Radiology, 166, 125 133. Hayes, WS, Davidson, AJ, Grimley, PM & Hartman, DS (1990). Extraadrenal retroperitoneal paraganglioma: clinical, pathologic and CT findings. American Journal of Roentgenology, 155, 1247 1250. Landsberg, L & Young, JB (1991). Harrison's Principles of Internal Medic#w, eds. Wilson, JD, Braunwald, E, lsselbacher, KJ, Petersdoff, RG, Martin, JB, Fauci, AS et al. 12th edn, pp. 1735-1739. McGraw-Hill, New York. Lane, RH, Stephens, D H & Reiman, H M (1989). Primary retroperitoneal neoplasms: CT findings in 90 cases with clinical and pathologic correlation. American Journal of Roentgenology, 152, 83 89. McCorkell, SJ & Niles, N L (1985). Fine-needle aspiration of catecholamine-producing adrenal masses: a possibly fatal mistake. American Journal of Roentgenology, 145, 113 114.
