[Clinical characteristics of intravascular large B cell lymphoma: a single-center retrospective study]

Objective: To investigate clinic-pathological characteristics, diagnosis, treatment and prognosis of intravascular large B cell lymphoma (IVLBCL) in China. Methods: Clinical and pathological records were analyzed from 12 IVLBCL patients diagnosed between Jan 2010 to Jun 2016. Kaplan-Meier method was used to estimate overall survival (OS), and univariate analysis was performed to identify prognostic factors. Results: A series of 12 patients with IVLBCL (median age, 53.8 years; range, 32-76 years; 6 males and 6 females) was reviewed. Fever was the most common symptom (10/12), respiratory symptoms (cough, pleural effusion, dyspnea, 50%) and hemophagocytic lymphohistiocytosis (50%) were frequently observed, and only 12 patients had neurological symptom. All patients had elevated lactic dehydrogenase and serum ferritin. International Prognostic Index score was high in 75% of total patients. All patients had extra-nodal involved, pulmonary (6/12) and bone marrow (4/12) were frequently involved. Large lymphoid cells within vessel lumina or sinuses were observed in all patients. These cells were large, with scant cytoplasm, vesicular nuclei, and one or more nucleoli, and the structures of vessels and sinus were reserved. CD20 and CD79a were positive in all cases. 11patients received rituximab combined CHOP regimen chemotherapies, overall response rate (ORR) was 90.1%, and complete response rate was 66.7%. Median survival time and median progression time were not reached after a median follow-up of 20 months. Univariate analysis revealed that no clinical characters were associated with OS. Conclusion: As a rare variant of DLBCL, IVLBCL presented with pulmonary involved frequently, and trans-bronchial lung biopsy had good positive rates. Rituximab contained chemotherapy was the backbone for IVLBCL.