Pulmonary inflammatory pseudotumor

BFig. 4. The resected tumor (arrow) in the left upper lobe was 38 32 mm insize with a relatively regular margin and a solid and elastically soft interior. A:Left upper lobe. B: A cut surface of the tumor.

AA

BFig. 5. Pathological findings showed inflammatory cell infiltration involving lymphocytes and plasma cells, fibrosis
and spindle-shaped mesenchymal cells with hematoxylin and eosin staining of low power field (A) and high power
field (B). Bar = 500 µm in A and 50 µm in B.

modalities, the pseudotumor is seen as an isolated
and well-defined shadow with a round to oval
shape, and clinical differentiation from lung cancer
is often difficult (Ishida et al., 1989; Kobashi et al.,2006). In the present patient as well, we suspectedlung cancer from the clinical symptoms and image
findings, and performed the CT-guided lung biopsy,
but no malignant cells were observed. However,
FDG-PET of the tumor further showed a high FDG
uptake, so we highly suspected lung cancer again
and considered performing video-assisted thoracic
surgery. Recently, FDG-PET has been widelyused as an adjunct for the diagnosis of lung cancer(Ung et al., 2007). A higher level of the standard
FDG uptake is correlated to poorer prognosis

Discussion
Inflammatory pseudotumor of the lung is asolitary, non-neoplastic, space-occupying lesionin which collagenic fiber, inflammatory cells andmesenchymal cells are blended together in various
amounts (Bernardi et al., 1983). In 2000, Cerfolio
et al. reported that among 56,400 patients treatedwith chest surgery over 50 years at the Mayo
Clinic, inflammatory pseudotumor of the lung wasobserved in only 23 patients (0.04%), of which 18
patients (78%) were involved with symptoms suchas coughing, hemosputum, shortness of breathand chest pain (Cerfolio et al., 2000). In imaging
71

Y. Takagi et al.

(Berghmans et al., 2008). However, FDG-PET
often shows positive even for inflammatory lungdisease. Of 66 patients with lung nodule shadowsthat were positive in FDG-PET, 7 patients werefalse positive for inflammatory lung disease: oneof the 7 had an inflammatory pseudotumor of thelung (Higashi et al., 2001). Because inflammatory
pseudotumor of the lung is a rare disease,application of FDG-PET has been seldom reported(Slosman et al., 1994). But, FDG-PET shows high
FDG uptake for inflammatory pseudotumor of thelung, and differentiation from liver cancer or lungcancer is difficult (Kawashima et al., 2006). In
addition, it is characteristic of FDG-PET that thehilar and the mediastinal lymph nodes also show
positive, as observed in the present patient. FDGPET is also useful in diagnosing metastasis oflung cancer to lymph nodes (Melek et al., 2008),
which makes differentiation of lung pseudotumor
from lung cancer more difficult. Even though
inflammatory pseudotumor of the lung is benign,
3 of 5 patients with incomplete resection had arecurrence (Cerfolio et al., 2000), or 3 of 18 treatedpatients had a recurrence (Melloni et al., 2005).
Therefore, we had no choice but to perform a left
upper lobectomy in the present patient, because
sufficient resection margins are required. The
postoperative course was good, and we believe that
this was an appropriate choice. Cases of recurrence
after complete resection have been reported(Dehabreh et al., 1999) with some multiple tumor
cases (Lee et al., 2005; Kobashi et al., 2006). We
emphasize that the present patient will requirea careful follow-up. Along with the progress indiagnostic imaging, inflammatory pseudotumorof the lung has been increasingly observed. The
characteristics of FDG-PET findings should also
be fully understood.

small cell lung cancer (NSCLC): a systematic review
and meta-analysis (MA) by the European Lung Cancer Working Party for the IASLC Lung Cancer Staging Project. J Torac Oncol 2008;3:6–12.
2 Bernardi RS, Lee SS, Chen HP, Stines GJ. Inflammatory pseudotumors of the lung. Surg Gynecol
Obstet 1983;156:89–96.
3 Cerfolio RJ, Allen MS, Nascimento AG, Deschamps
C, Trastek VF, Miller DL, et al. Inflammatory pseudotumors of the lung. Ann Thorac Surg 1999;67:933–936.
4 Dahabreh J, Zisis C, Arnogiannaki N, Katis K. Inflammatory pseudotumor: a contcroversial entity.
Eur J Cardiothorac Surg 1999;16:670–673.
5 Higashi KK, Ueda Y, Sakuma T, Seki H, Oguchi M,Taniguchi M, et al. Comparison of FDG PET and TI
SPECT in evaluation of pulmonary nodules. J NuclMed. 2001;42:1497–1498.
6 Ishida T, Oka T, Nishino T, Tateishi M, Mitsudomi
T, Sugimachi K. Inflammatory pseudotumor of thelung in adults: radiographic and clinicopathologicalanalysis. Ann Thorac Surg 1989;48:90–95.
7 Kawamura E, Habu D, Tsushima H, Torii K, Kawabe
J, Ohsawa M, et al. A case of hepatic inflammatory
pseudotumor identified by FDG-PET. Ann Nucl Med
2006;20:321–323.
8 Kobashi Y, Fukuda M, Nakata M, Irei T, Oka M.
Inflammatory pseudotumor of the lung: clinicopathilogical analysis in seven adult patients. Int J
Clin Oncol 2006;11:461–466.
9 Lee HL, Kim L, Lee KH, Kim KH, Kim CW. A
case of pulmonary inflammatory pseudotumor:
recurrence appearing as several consolidative lesion after complete resection. Kor J Intern Med
2005;20:168–172.
10 Melek H, Gunluoglu MZ, Demr A, Akin H, Olcmen A,Dincer SI, et al. Role of positron emission tomography in mediastinal lymphatic staging of non-small celllung cancer. Eur J Cardiothorac Surg 2008;33:294–299.
11 Melloni G, Carretta A, Ciriaco P, Arrigoni G, Fieschi
S, Rizzo N, et al. Inflammatory pseudotumor of thelung in adults. Ann Thorac Surg 2005;79:426–432.
12 Slomsman DO, Spilliopoulos A, Keller A, Lemoine
R, Besse F, Couson F, et al. Quantitative metabolic
PET imaging of a plasma cell granuloma. J Thorac
Imaging 1994;9:116–119.
13 Ung YC, Maziak DE, Vanderveen JA, Smith CA,
Gulenchyn K, Lacchetti C, et al. 18F-Fluorodeoxyglucose positron emission tomography in the diagnosis and staging of lung cancer: a systematic review.
J Natl Cancer Inst 2007;99:1753–1767.

References
1 Berghmans T, Dusart M, Paesmans M, HosseinFoucher C, Buvat I, Castagne C, et al. Primary tumor
standardized uptake value (SUV max) measured on
fluorodeoxyglucose positron emission tomography(FDG-PET) is a prognostic value for survival in non-Received June 20, 2008; accepted July 22, 2008
Corresponding author: Hiroshige Nakamura, MD72