27-year-old African American female with no significant past medical history presented with fever, productive cough, and significant facial puffiness for the past 15 days. She also reported night sweats and unintentional weight loss of 15 lbs. in the past 1 month. She visited emergency twice in the past one month and was also prescribed a respiratory quinolone for 7 days by her primary medical doctor but her symptoms did not improve significantly. Patient denies any similar episode prior to this presentation. No significant family history was found. She is a nonsmoker and emigrated from Ghana in childhood.
Physical examination was remarkable for mild respiratory distress, visible facial puffiness, decreased breath sounds, dullness on percussion, and increased tactile fremitus on right side of the chest.
Vital signs were within acceptable limits except for tachycardia (127) and tachypnea (22) on the day of presentation. Laboratory investigations revealed a normal complete blood count with hemoglobin of 12 g/dL, white blood cells of 8300/uL, and platelets of 424000/uL. Other significant laboratory data included elevated lactate level of 3.1 and lactate dehydrogenase of 1475 IU/L.
Chest X-ray revealed a large right-sided infiltrate with pleural effusion (Figure 1). She was admitted to the Intensive Care Unit with airborne precautions with working diagnosis of bacterial pneumonia to rule out pulmonary tuberculosis as she reported fever and night sweats for one month. Three sets of sputum samples were collected on three different occasions for acid-fast bacilli testing which were reported negative. Later chest CT without contrast revealed 10 x 14 x 16 cm mass in the right lung without hilar lymphadenopathy, small pericardial effusion, bilateral pleural effusions, and compressive atelectasis of the right lung (Figure 2) and possible differentials were pleural fibroma, sarcoma, pulmonary pleural blastoma, and primary pulmonary lymphoma (no palpable lymph nodes). The patient subsequently underwent chest CT with contrast for possible superior vena cava obstruction (Figure 3) and CT guided core biopsy of the right lung mass for tissue diagnosis (Figure 4).
The pathology report revealed atypical B cell rich lymphoid infiltrate consistent with large B cell lymphoma (Figure 5). Immunohistochemistry showed expression of vimentin, leukocyte common antigen (LCA), cluster of differentiation 20 (CD20), CD79a, and CD99 but not of CD3, CD5, CD10, or thyroid transcription factor- (TTF-) 1. Based on these findings, mature large B cell lymphoma was diagnosed.
Initially, patient received "involved field radiation" for two days because of the bulky tumor size and superior vena cava involvement. Patient was started on R-CHOP (rituximab + cyclophosphamide, doxorubicin, vincristine, and prednisone). She responded well to the treatment and tumor was shrunken down on repeated CXR (Figure 6).