27-year-old Bosnian male was admitted at the Department of Thoracic Surgery, Clinical Center of the University of Sarajevo because of the round lesion in lower right lobe, previously diagnozed on his chest X-ray. X-ray was performed because of the repetitive hemoptysis, cough and tachycardia.  
The specimen of the lung was analyzed intraoperatively. The specimen was composed of the preserved lymphatic follicles and plasma cells (Kappa & Lambda positive). Among these proliferating small lymphocytes were noticed /CD20(+), bcl-2(+) and bcl-6(-). Ki-67 staining (MIB antibody) was very low.  
The right lower lobe was surgically removed and the specimen is shown here.  
In basal parts of right lobe a big, white tumor mass (60x50x45 mm) were detected. The mass was well-circumscribed, closely related to visceral pleura.  
Microscopically, the central area of the specimen was composed of the areas with fibrosis, necrosis with proliferation of stromal (myo)fibroblasts. These changes significantly reduced the alveolar spaces. There were also some histiocytes and extravated erythrocytes with areas of fresh and old hemorrhage. Periferally, there were infiltration of small round lymphocytes with finely dispersed chromatin and proliferation of plasma cells.  
Immunohistochemistry: CK-pan (positive within epithelial cells); Bcl-2 (positive within lymphocytes), CD20 (positive), SMA (positive), Kappa (positive) and Lambda (positive). Ki-67 was very low.  
Histochemistry: PAS (negative), Pearls (positive).  
Additionally, we analyzed the patient's history of disease. He has been exposed to industrial dusts as a proffesional mechanician. No other diseases or disorders.  
Differential diagnosis: lymphoma in combination with interstitial fibrosis; rheumatoid lung disease; pulmonary hemosiderosis?  
 
I added this case to this section though not quite sure that it belongs to this category.  
Please, give your opinion whether this is inflammatory myofibroblastic tumor or intestitial fibrosis associated with lymphoma? ALK-1 staining will be performed very soon and updated here.  
 
imported on 2006-12-03 10:48:25 originally owned by semir