Traumatic neuroma around the celiac trunk after gastrectomy mimicking a nodal metastasis: a case report.

Abstract

Traumatic neuroma is a well-known disorder that occurs after trauma or surgery involving the peripheral nerve and develops from a nonneoplastic proliferation of the proximal end of a severed, partially transected, or injured nerve. We present a case of traumatic neuroma around the celiac trunk after gastrectomy in a 56-year-old man, which was confirmed by pathology. CT demonstrated the presence of a lobulated, homogeneous, hypoattenuating mass around the celiac trunk, mimicking a nodal metastasis.

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Korean J Radiol 8(3), June 2007
Traumatic Neuroma around the Celiac
Trunk after Gastrectomy Mimicking a
Nodal Metastasis: A Case Report
Traumatic neuroma is a well-known disorder that occurs after trauma or
surgery involving the peripheral nerve and develops from a nonneoplastic prolif-
eration of the proximal end of a severed, partially transected, or injured nerve. We
present a case of traumatic neuroma around the celiac trunk after gastrectomy in
a 56-year-old man, which was confirmed by pathology. CT demonstrated the
presence of a lobulated, homogeneous, hypoattenuating mass around the celiac
trunk, mimicking a nodal metastasis.
raumatic neuroma is a well-known disorder that occurs after trauma or
surgery involving the peripheral nerve and develops from a nonneoplas-
tic proliferation of the proximal end of a severed, partially transected, or
injured nerve (1, 2). However, in the abdomen, traumatic neuromas have been
sporadically reported to occur in the bile duct (3 7). We present here a case of
traumatic neuroma around the celiac trunk after gastrectomy that mimicks a nodal
metastasis.
CASE REPORT
A 56-year-old man presented with a lobulated mass around the celiac trunk. This
patient had undergone a distal gastrectomy with gastroduodenostomy for early gastric
cancer nine years previously and a subtotal gastrectomy with gastrojejunostomy for
recurred gastric cancer in the remnant stomach five months previously. According to
the 5th American Joint Committee on Cancer (AJCC) TNM classification, the recurred
gastric cancer was a stage II lesion (T3 N0 M0) based on the pathology (Fig. 1A). On
the present admission, the patient showed no apparent discomfort and a physical
examination was normal. The laboratory tests showed no abnormal findings. The
carcinoembryonic antigen level was 1.6 ng/mL (< 5.0 ng/mL) and the serum carbohy-
drate antigen 19 9 level was 5.7 U/mL (< 39 U/mL).
A three-phase CT scan showed a lobulated, mildly enhanced, homogeneous, hypoat-
tenuating mass just distal to the celiac trunk (Figs. 1B E). This mass encased the
common hepatic artery, splenic artery, proper hepatic artery, and the gastroduodenal
artery (Figs. 1B, C). However, CT angiography showed no luminal narrowing or
irregularities of these arteries (Fig. 1F). A fluorodeoxyglucose (FDG)-positron emission
tomographic (PET) scan showed no increased uptake in the celiac region (mean
standardized uptake value of 3.2) (Fig. 1G). Because it was difficult to distinguish a
benign mass from a nodal metastasis, a decision was made to perform surgery.
During surgery, an ill-defined, irregular, pale tan, firm mass was seen around the
Jung Hyeok Kwon, MD1
Seung Wan Ryu, MD2
Yu Na Kang, MD3
Index terms:
Traumatic neuroma
Celiac trunk
Gastrectomy
Korean J Radiol 2007;8:242-245
Received September 17, 2006; accepted
after revision February 6, 2007.
Department of 1Diagnostic Radiology,
2Surgery, 3Pathology, Dongsan Medical
Center, Keimyung University School of
Medicine, Daegu 700-712, Korea
Address reprint requests to:
Jung Hyeok Kwon, MD, Department of
Diagnostic Radiology, Dongsan Medical
Center, Keimyung Univesity School of
Medicine, 194 Dongsan-dong, Jung-gu,
Daegu 700-712, Korea.
Tel. (8253) 250-7770
Fax. (8253) 250-7766
e-mail: kjh2603@dsmc.or.kr
T

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Traumatic Neuroma Mimicking Nodal Metastasis
Korean J Radiol 8(3), June 2007
243
AB
CD
Fig. 1. A 56-year-old man with traumatic neuroma around the celiac trunk.
A. A contrast-enhanced abdominal CT scan in the arterial phase showed no mass present around the celiac trunk 5 months previously.
B, C. Contrast-enhanced abdominal CT scans in the arterial phase show a lobulated hypoattenuating soft tissue mass in the celiac
region encasing the common hepatic artery, splenic artery, gastroduodenal artery, and the proper hepatic artery.
D, E. Contrast-enhanced abdominal CT scans in the portal phase (D) and equilibrium phase (E) show a mild homogeneous enhance-
ment of this mass.
F. Volume-rendering CT angiography shows that the celiac trunk and its tributaries are patent without vessel wall irregularities, or vessel
caliber stenosis.
EF

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celiac trunk. A frozen section revealed the presence of
fibrotic connective tissue without malignant cells, and the
proliferation of neural tissue. The tumor mass was resected
in several pieces (Fig. 1H). The size of the mass was 3.0
3.5 1.0 cm in aggregates. A histologic examination
showed proliferation of neural tissue and fibrotic change,
but there was no evidence of definite malignant cells. The
celiac mass consisted of small and large proliferating
fascicles of nerve in a background of collagen and fat tissue
(Fig. 1I, J). These findings were compatible with the
presence of a traumatic neuroma.
On a follow up CT scan performed seven months later,
there was no evidence of a soft tissue mass in the celiac
region.
DISCUSSION
Traumatic or amputation neuroma is a well-known
disorder that occurs 1 12 months after trauma or surgery
involving the peripheral nerve. Rather than representing a
neoplasm, neuroma represents a reactive hyperplasia of
nerve tissue and usually occurs at the proximal end of a
severed nerve (2).
In the abdomen, neuromas have been reported to occur
in the bile duct after cholecystectomy (3, 4), bile duct
surgery (5), orthotopic liver transplantation (6), and blunt
abdominal trauma (7). The neuromas occur as most of the
common bile duct is surrounded by a delicate net of
sympathetic and parasympathetic nerve fibers that are
derived from the celiac plexus. Most patients have no
Kwon et al.
244
Korean J Radiol 8(3), June 2007
GH
Fig. 1. G. Fluorodeoxyglucose (FDG)-positron emission tomography (PET) image shows no increased uptake around the celiac trunk
with a mean standardized uptake value of 3.2.
H. The resected celiac mass is composed of several pieces of irregular pale tan to yellow firm tissue, measuring 3.5
aggregates.
I, J. Microscopically, the celiac mass consists of small (arrows) and large (asterisk) proliferating fascicles of nerve in a background of
collagen and fat tissue (Hematoxylin & Eosin staining,
100). The celiac mass is composed of a haphazard proliferation of nerve
fascicles, including axons with their investitures of myelin, Schwann cells, and fibroblasts (Hematoxylin & Eosin staining,
3.0 1.0 cm in
200).
IJ

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Korean J Radiol 8(3), June 2007
245
symptoms, but some patients have upper abdominal pain
and jaundice. Treatment of this disorder is unnecessary
unless the patient has symptoms.
The celiac plexus, surrounding the root of the celiac
arterial trunk, are nerve networks consisting of both
sympathetic and parasympathetic fibers. Injury to celiac
plexus during lymph node dissection for gastric surgery is
possible.
Arterial invasion can be suggested with high specificity
when either arterial embedment, tumor involvement
exceeding one-half of the circumference of the vessel,
vessel wall irregularities, or vessel caliber stenosis is
present (8). In the present case, the mass encircled the
whole circumference of multiple vessels, but in any of the
encircled vessels, wall irregularity or vessel caliber stenosis
was not seen with CT angiography. This finding may be
unusual to a malignant tumor.
The tumor was homogeneous and hypovascular in
arterial, portal, and equilibrium phases of an enhanced CT
scan. There was also no increased uptake of FDG on the
FDG-PET scan, suggestive of the presence of a benign
hypovascular mass.
FDG is not a cancer-specific agent. False positive findings
have been reported in cases of active inflammation and
infection, and malignant tumors with low metabolic
activity or tumors smaller than 1.0 cm in diameter often
show false negative results (9). In detecting local lymph
node metastasis from stomach cancer, the sensitivity of
PET was lower than that of CT, and the specificity was
higher. However, the overall accuracy of PET was not
significantly different from that of CT in detecting both
local (63% vs. 75%) and distant (95% vs. 89%) lymph
node metastasis (10).
Our initial impression suggested that the mass was a
conglomerated nodal metastasis or postoperative
granuloma. A preoperative diagnosis of traumatic neuroma
is difficult to make, despite all modern imaging techniques,
and in most cases, a final diagnosis is made at surgery.
In conclusion, the imaging finding of traumatic neuroma
around the celiac trunk was a homogeneous hypovascular
mass without narrowing or irregularity of encased arteries
and without increased uptake on PET-CT. Although from a
clinical standpoint, establishing an accurate preoperative
diagnosis is difficult to perform, the presence of a traumatic
neuroma should be included in the differential diagnosis of
a mass around the celiac trunk in a patient that has
undergone celiac nodal dissection.
References
1. Murphey MD, Smith WS, Smith SE, Kransdorf MJ, Temple HT.
From the archives of the AFIP. Imaging of musculoskeletal
neurogenic tumors: radiologic-pathologic correlation.
Radiographics 1999;19:1253-1280
2. Yabuuchi H, Kuroiwa T, Fukuya T, Tomita K, Hachitanda Y.
Traumatic neuroma and recurrent lymphadenopathy after neck
dissection: comparison of radiologic features. Radiology
2004;233:523-529
3. Nagata Y, Tomioka T, Chiba K, Kanematsu T. Traumatic
neuroma of the common hepatic duct after laparoscopic
cholecystectomy. Am J Gastroenterol 1995;90:1887-1888
4. Shimura K, Tamada K, Asada M, Watabiki N, Wada I, Tanaka
N, et al. Intraductal ultrasonography of traumatic neuroma of
the bile duct. Abdom Imaging 2001;26:632-634
5. van Gulik TM, Brumelkamp WH, Lygidakis NJ. Traumatic
neuroma giving rise to biliary obstruction after reconstructive
surgery for iatrogenic lesions of biliary tract a report of three
cases. Hepatogastroenterology 1989;36:255-257
6. Mentha G, Rubbia-Brandt L, Orci L, Becker C, Giostra E, Majno
P, et al. Traumatic neuroma with biliary duct obstruction after
orthotopic liver transplantation. Transplantation 1999;67:177-
179
7. Katsinelos P, Dimiropoulos S, Galanis I, Tsolkas P, Paroutoglu
G, Arvaniti M, et al. Biliary stricture due to neuroma after an
innocent blunt abdominal trauma. Surg Endosc 2002;16:1494
8. Li H, Zeng MS, Zhou KR, Jin DY, Lou WH. Pancreatic
adenocarcinoma: the different CT criteria for peripancreatic
major arterial and venous invasion. J Comput Assist Tomogr
2005;29:170-175
9. Chang JM, Lee HJ, Goo JM, Lee HY, Lee JJ, Chung JK, et al.
False positive and false negative FDG-PET scans in various
thoracic diseases. Korean J Radiol 2006;7:57-69
10.Chen J, Cheong JH, Yun MJ, Kim J, Lim JS, Hyung WJ, et al.
Improvement in preoperative staging of gastric adenocarcinoma
with positron emission tomography. Cancer 2005;103:2383-
2390