Intravascular Lymphomatosis: A Study of 20 Cases in Thailand and a Review of the Literature

BackgroundAccording to the World Health Organization classification (2001), intravascular large B-cell lymphoma (IVLBCL) is characterized by the presence of lymphoma cells only in the lumina of small vessels. It has not been proven whether IVLBCL is a specific clinicopathologic entity. Intravascular large B-cell lymphoma and other intravascular lymphomatoses (IVLs), including IVL with B-cell phenotype and extravascular growth (B-IVL) and IVL with T-cell phenotype (T-IVL), were compared in a series of cases diagnosed at a single institution and in cases reported in the literature.Patients and MethodsTwenty cases of IVL diagnosed among 1826 consecutive cases of non-Hodgkin's lymphoma (NHL,1.1%) at Siriraj Hospital included 3 cases of IVLBCL, 14 cases of B-IVL, and 3 cases of T-IVL. In the literature, 102 cases of IVLBCL, 88 cases of B-IVL, and 18 cases of T-IVL were described in sufficient detail to be analyzed.ResultsAll 3 groups were quite similar in clinical manifestations and outcome. Contrary to the previous review of 79 cases of IVL in 1989, blood, marrow, and nodal involvement could be detected in approximately 30% of cases. Patients who received chemotherapy had better survival than patients without treatment—statistically significant in IVLBCL and B-IVL (P < 0.05). Cases with skin involvement had better survival than cases without skin involvement—statistically significantly in T-IVL (P < 0.05).ConclusionThese results indicate that IVLBCL is not different from B-IVL or T-IVL in a biologic sense, and IVL seems to be better terminology than IVLBCL because it includes the T-cell phenotype that constitutes approximately 9% of cases. Early diagnosis is very important because chemotherapy significantly prolongs survival.