a 52-year - old male was admitted to our hospital suffering with cough , fever and sweating for the previous two weeks . there was no history of treatment or medication for diabetes mellitus and hypertension . the patient was a smoker ( 45 pack - years ) and he drank alcohol . on the posteroanterior chest radiograph , variable sized nodules and masses were seen in both lower lobes and the right upper lobe ( fig . the contrast enhanced chest ct scan revealed variable sized masses in the right upper lobe and both lower lobes , and the masses displayed central necrosis ( fig . no endobronchial lesion was visualized on bronchoscopy . a ct - guided percutaneous transthoracic needle biopsy ( ptnb ) the histologic examination of the percutaneous transthoracic needle biopsy specimen showed diffuse infiltrates of large lymphoid cells ( fig . 1 g ) and they were negative for cd20 , cd30 ( ki-1 ) and cd56 . the specimen showed nearly normal , fully matured myeloids and an adequate number of megakaryocytes without lymphomatous involvement . 18f - fluoro-2-deoxyglucose positron emission tomography ( fdg - pet ) showed multiple hypermetabolic masses with photopenic defects ( maxsuv 8.9 ) in both lungs ( fig . finally , we diagnosed the patient as suffering with primary pulmonary peripheral t - cell lymphoma not otherwise specified . the follow - up contrast enhanced chest ct scan obtained two months after the initial diagnosis showed aggravated t - cell lymphoma involvement in the lungs ( fig . we observed multifocal irregular enhancing lesions in both parietal cortical areas on the brain ct and mri obtained four months after the initial diagnosis and this all suggested multiple parenchymal and meningeal metastases . sadly , the patient eventually expired from pneumonia during icu care after multiple episodes of neutropenic fever . primary pulmonary lymphoma is diagnosed according to the following strict criteria : 1 ) the lung , bronchus or both are involved without evidence of mediastinal adenopathy or a mass on the chest radiographs , 2 ) extrathoracic lymphoma was not previously diagnosed and 3 ) there was no evidence of extrathoracic lymphoma or lymphatic leukemia at the time that primary lymphoma of the lung was diagnosed . further , for making the diagnosis of primary pulmonary lymphoma , the disease is not present outside of the thorax for least three months after the initial diagnosis ( 2 ) . low - grade b - cell lymphoma is the most frequent form of primary pulmonary lymphoma ; however , primary pulmonary peripheral t - cell lymphoma is extremely rare . peripheral t - cell lymphoma ( ptcl ) comprises a group of rare , aggressive cancers that develop from t - cells that are at different stages of maturity . the world health organization ( who ) has divided the various types of ptcl into two main categories : 1 ) precursor t - cell neoplasms , which include precursor t - lymphoblastic lymphoma / leukemia ; and 2 ) peripheral t - cell neoplasms , which are subcategorized as predominantly leukemic disease , predominantly disseminated disease , predominantly extranodal disease and predominantly nodal disease . the cases that do not match one of the defined entities of ptcl are best categorized as ' not otherwise specified ' , reflecting the fact that we do not yet understand everything about lymphomas or the immune system ( 3 ) . the incidence of ptcl tends to be higher in korea ( 25% of the cases of nhl ) than in europe ( 10 - 15% of the cases of nhl ) , as well as the incidence of peripheral t - cell lymphoma not otherwise specified ( ptcln ) is higher in korea ( 11% of the cases of nhl ) that in europe ( 4% of the cases of nhl ) ( 3 , 4 ) . patients with ptcln are usually adults with generalized disease ; the lymph nodes , liver and spleen may be involved . the most common radiologic finding of ptcln is generalized lymphadenopathy ( 3 , 5 ) . in patients with disseminated conditions , the imaging features are not distinguishable from those of the other subtypes of lymphoma in the disseminated state . our case shows a very unique feature of primary pulmonary ptcln as the disease presented as multiple lung masses with central necrosis and there was no disease involvement at any other site on the detailed work up . the radiologic appearance of central necrosis in the consolidation or mass can also present in such benign conditions as abscess , lung infarction , c - anca ( anti - neutrophil cytoplasmic antibody)-associated granulomatous vasculitis and carcinomas . the thick wall and irregular inner margin are more frequently seen in malignant lesions , as was noted in our case . this may be due to the rapid tumor growth and it tends to occur in large nodules and masses . a cavity with air - fluid levels may be apparent when there is communication between an adjacent bronchus and a necrotic tumor mass . there has been a report about extranodal ptcl showing a pattern of photopenic defect on pet scanning , like was seen in our case ( 6 ) . this photopenic defect correlates well with central necrosis , yet necrosis is an uncommon pet scan finding for lymphoma . tumor necrosis generally correlates with hypoxia and it is a predictor of a poor prognosis for patients with malignant tumor . tumor hypoxia plays a major role in tumor progression and resistance to treatment , like what happened in our case ( 6 ) . for most of the subtypes of ptcl , the treatment regimen is typically chop - based chemotherapy ( cyclophosphamide , doxorubicin , vincristine and prednisone ) , or epoch ( etoposide added to chop ) in the frontline setting ( 7 ) . adult t - cell leukemia or lymphoma has a poor prognosis due to the life - threatening complications that include infections and hypercalcemia ( 8) . the clinical course is usually aggressive , and relapses are more common for t - cell leukemia or lymphoma than for the b - cell lymphomas of a similar histologic grade ( 9 , 10 ) . we report herein on a rare case of ptcl and we present the ct and pet images of this often fatal neoplasm .
primary pulmonary t - cell lymphoma is an extremely rare malady , and we diagnosed this in a 52-year - old male who was admitted to our hospital with cough for the previous two weeks . 
 the chest ct demonstrated multiple variable sized mass - like consolidations with low density central necrosis in the peripheral portion of both the upper and lower lobes . 
 positron emission tomography ( pet ) showed multiple areas of hypermetabolic fluorodeoxyglucose ( fdg ) uptake in both lungs with central metabolic defects , which correlated with central necrosis seen on ct . 
 the histological sample showed peripheral t - cell lymphoma of the not otherwise specified form . 
 the follow - up ct scan showed an increased extent of the multifocal consolidative lesions despite that the patient had undergone chemotherapy .