Use of Fluorodeoxyglucose-Positron Emission Tomography in the Diagnosis of Intravascular Diffuse Large B-Cell Lymphoma
Patient 1
A white man aged 67 years, with diastolic heart failure and chronic obstructive pulmonary disease, presented to the emergency department (ED) with shortness of breath. The initial laboratory results were significant for a newly elevated creatinine level of 2.06 mg/dL and a brain natriuretic peptide level of 648 pg/mL.
Imaging studies included a chest radiograph, a ventilation/perfusion scan, and an echocardiogram, as well as a right heart catheterization. All were nondiagnostic.
The patient's shortness of breath persisted despite treatment with diuretics, antibiotics, and steroids. Further laboratory workup revealed an elevated lactate dehydrogenase (LDH) level of 1,338 IU/L. A bone marrow biopsy performed because of concern about malignancy was unremarkable. Flow cytometry of the bone marrow aspirate did not reveal clonal B- or T-cell populations. Immunohistochemical staining was not performed. During this hospitalization for shortness of breath, the patient's mental staus began to decline, and his oxygen requirements increased. The patient was intubated but expired 48 hours after mechanical ventilation was initiated.
Patient 2
A white woman aged 67 years presented to the ED with generalized weakness, fatigue, and nausea. The patient’s medical history was significant for a diagnosis of stage IIIa ovarian cancer. She was treated with surgical resection and completed 6 cycles of adjuvant carboplatin and paclitaxel 3 months prior to this presentation. She had good response to treatment with normalization of CA-125.
After completion of chemotherapy, the patient was found to have persistent anemia and thrombocytopenia. Admission laboratory results were significant for a hemoglobin level of 8.4 g/dL, a platelet count of 20,000/μL, and an LDH level of 1,220 IU/L.
Chest, abdomen, and pelvis CT scans showed mesenteric adenopathy and splenomegaly (Figures 3A, 3B, and 3C) compared with prior imaging. Bone marrow biopsy revealed large lymphoid cells with scant cytoplasm and irregular nuclei, primarily within blood vessels and sinusoids consistent with IVLBCL (Figure 4). Flow cytometry of the bone marrow specimen showed an abnormal B-cell population with expression CD20, CD19, FMC-7, and dim κ light chain restriction. The cells were negative for CD5 and CD10. Immunohistochemical staining was positive for CD20, CD79a, PAX5, BCL-2 , and MUM1.
The patient was treated with 4 cycles of cyclophosphamide, doxorubicin, vincristine, prednisone, and rituximab, plus intrathecal methotrexate. The chemotherapy dose was reduced in the final cycle because of neuropathy in the hands and feet. The patient had undergone autologous stem-cell transplantation to allow high-dose chemotherapy. She was doing well more than 5 months after her transplant without evidence of recurrent disease.
Patient 3
A white man aged 76 years presented to the ED with cutaneous nodules, weight loss, fatigue, fevers, and epigastric pain. The patient’s medical history was significant for asymptomatic lymphoplasmacytic lymphoma diagnosed 2 months earlier, which had not required treatment. Laboratory results on admission revealed transaminitis, mild anemia with a hemoglobin level of 11 g/dL, and LDH level of 497 IU/L.




