Inflammatory
pseudotumour is a rare lesion especially in childhood. The exact aetiology
of this lesion is unknown, but it is generally regarded as a benign,
reactive inflammatory condition although some may recur or metastasize.
We present here our experience in the management of a case of inflammatory
pseudotumour with a review of literature.
Introduction
Inflammatory pseudotumour, also called inflammatory myofibroblastic
tumour or plasma cell granuloma, is a rare, benign tumour like lesion
which was first described in 1953 by Pack and Baker.1 Histologically
it is characterized by a proliferation of spindle shaped cells, myofibroblasts
mixed with inflammatory cells consisting of plasma cells, lymphocytes
and occasionally histiocytes.2 The liver is a relatively
common site of origin. While the total number of cases reported in
literature is approximately 50, only 15 paediatric inflammatory pseudotumour
cases have been reported in literature.3 We report our
experience in the management of a case of inflammatory pseudotumour.
Case Report
A 7 month old girl was admitted to our hospital for an abdominal mass
that was palpated by a local physician whom she had visited for cough
and cold. There was no history of fever or any other major medical
or surgical history in the past. On admission, physical examination
revealed a nontender, firm mass in the right upper quadrant. Laboraory
investigations including the liver function tests and alpha foetoprotein
were all within normal ranges except for haemoglobin 5.9 g/dl, WBC
count were 12,500/cmm, and ESR was 110 mm at end of 1 hour. Ultrasound
examination showed a single, mixed echogenic solid lesion with few
anechoic cystic areas in the anterior inferior segment of the liver.
CT scan revealed a 6.3 x 5.4 x 6.0 cm size well defined heterogeneously
enhancing noncalcified mass lesion with central hypodensity seen arising
from segment IV and
V with a large exophytic component which is compressing the gallbladder
and displacing the bowel loops. A trucut liver biopsy showed hepatocytes
entrapped within and amidst plump fibroblastic cell, with lymphocytes
and plasma cells. The patient underwent an exploratory laparotomy
and the exophytic liver mass was resected by partial resection of
the anterior inferior segment of the right lobe. Histologically, the
mass was well circumscribed with a pseudocapsule and was charaterized
by proliferation of elongated spindle shaped myofibroblasts with diffuse
infiltration of plasma cells and lymphocytes. The post operative course
was uneventful and she is now 4 months postsurgery and is doing well.
Discussion
Inflammatory pseudotumour is a rare benign condition and 15 paediatric
cases have been reported in literature till date.3 the
age at diagnosis of the patients, 6 boys and 9 girls, ranged from
10 months to 15 years (median 6 years). The lesion was solitary in
13 patients and multiple in 2, with the size of the lesion exceeding
5 cm in 9 patients. The lesion has been seen in various organs and
tissues namely lungs, mesentery of intestines, omentum, stomach, spleen,
ovary with liver been the common site of origin.4-6 Surgical
resection was the usual treatment except for 1 patient whose unresectable
lesion was treated with prednisolone. All the patients recovered and
no death was reported.3
 |
| Fig.
1 : CT scan showing a well defined heterogeneously enhancing
noncalcified mass lesion seen arising from segment IV and V compressing
the gall bladder and displacing the bowel loops |
|
Inflammatory pseudotumour
has been believed to be a lesion caused by an inflammatory reaction.
According to the hypothesis of Horiuchi et al,7 micro-organisms
seed into the hepatic parenchyma through the portal vein and induce
various degree of inflammatory reaction, resulting in granulomatous
inflammation. Other mechanisms have been proposed including an immune
reaction,8-108-10 intraparenchymal haemorrhage and necrosis,9
occlusive phlebitis of the intrahepatic veins,8,9 a secondary
reaction to intrahepatic rupture of a biliary radical, or a suppurative
inflammatory process from ascending cholangitis.6
There are no specific laboratory or radiologic findings in inflammatory
pseudotumour of the liver. However inflammatory pseudotumour of the
liver is enhanced by extravasation of contrast material in fibrous
tissue on the delayed-phase CT (3 to 6 minutes after the injection
of contrast material).11 Affected patients have varying
degrees of nonspecific symptoms and inflammatory responses, such as
fever, impaired growth, leucocytosis, anaemia, thrombocytosis, and
an increase in the erythrocyte sedimentation rate or the CRP as was
seen in our case.
Inflammatory pseudotumours are usually considered benign and some
may actually resolve without treatment.12 It is, however,
known that some pseudotumours may recur or metastasize and some patients
die of the disease.13 Inflammatory pseudotumours are considered
to be polyclonal nonneoplastic lesion, however cytogenetics study
in an inflammatory pseudotumour of the intestine showed chromosomal
abnormality and a monoclonality of the cells suggesting that inflammatory
pseudotumour is not merely a tissue reaction to inflammation.4
Local recurrence or distant metastasis were seen in patients with
aneuploid lesion whereas no recurrence was observed in the patient
with diploid lesion.13 Hence inflammatory pseudotumour
are biologically heterogenous and include a wide range of lesions,
from those that may regress to those that may recur or metastasize.
Hence if the features are suggestive of an inflammatory pseudotumour
of the liver with AFP levels normal, the Trucut biopsy to establish
the diagnosis is essential and if the tumour is resectable, resection
should be the best way to examine the biological characteristics and
to control the disease.
References
1. Pack GT, Baker HW. Total right hepatic lobectomy: report of
a case. Ann Surg 1953; 138 : 53-8.
2. Souid AK, Ziemba MC, Dubansky AS, et al. Inflammatory myofibroblastic
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3. Sakai M, Ikeda H, et al. Inflammatory pseudotumor of the liver:
case report and review of the literature. J Pediatr Surg 2001; 36
: 663-6.
4. Treissman SP, Gillis DA, Lee CLY, et al. Omental-mesenteric inflammatory
pseudotumor: cytogenetics demonstration of genetic changes and monoclonality
in one tumor. Cancer 1994; 73 : 1433-7.
5. Maves CK, Johnson JF, Bove K, et al. Gastric inflammatory pseudotumor
in children. Radiology 1989; 173 : 381-3.
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8. Someren A. Inflammatory pseudotumor of the liver with occlusive
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10. Bahadori M, Aieebow AA. Plasma cell granuloma of the lung. Cancer
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11. Fukuya T, Honda H, Matusumata T, et al. Diagnosis of inflammatory
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12. Flisak ME, Budris DM, Olson MC, et al. Inflammatory pseudotumor
of the liver: appearance on MRI. Clin Imaging 1994; 18 : 1-3.
13. Biselli R, Ferlini C, Fattorossi A, et al. Inflammatory myofibroblastic
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