The natural history of intravascular lymphomatosis

Abstract

Intravascular lymphomatosis (IVL) is a rare and clinically devastating form of extranodal B‐cell non‐Hodgkin's lymphoma. We performed a comprehensive analysis of the literature on IVL's published between 1959 and 2011 and evaluated the natural history as well as identified prognostic and predictive factors in patients. Nonparametric two‐tailed Mann–Whitney U‐test and Mantel–Cox log rank test were used to evaluate the survival intervals and prognostic factors. Multivariate analysis of variance (MANOVA) and chi‐squared statistics were carried out to examine treatment‐related predictive factors. Of the 740 patients with IVL, 651 (88%) had a diagnosis of B‐cell lymphoma, 45 (6%) with T‐cell lymphoma, and 12 patients (2%) with NK cell lymphoma. Central nervous system (CNS) IVL had the highest proportion of postmortem diagnosis, 250 (60%) compared to 21 (8%) of skin, 28 (11%) of bone marrow (BM) and spleen, and 17 (7%) of lung IVL's. Age P = 0.0073), non‐CNS site of initial diagnosis (P = 0.0014), lactate dehydrogenase (LDH) P = 0.0112), and rituximab treatment (P < 0.0001) were favorable prognostic factors. Gender, ethnicity, hemoglobin, BM biopsy, and the type of imaging studies used were not significant. Rituximab and doxorubicin treatment worked significantly better in patients with age >71 and LDH >577 compared to nonrituximab, nondoxorubicin regimens (MANOVA 2 degrees of freedom, P = 0.0345), with a median time from treatment to death of 20.0 (95% confidence interval [CI] 14.0–N/A, n = 14) months versus 2.0 (95%CI 0.5–N/A, n = 5) (χ² = 4.7, P = 0.0304). Patients with CNS IVL relapsed primarily in the CNS (88%) while same‐organ relapse occurred less frequently in skin (23%), BM and spleen (50%) and lung (20%) IVL's. Our results indicate that IVL is primarily a disease of B‐lymphoma cells. Timely diagnosis and treatment with rituximab‐based chemotherapy improve patient survival. The pattern of recurrence is different between CNS IVL and IVL's in other organs.