Analysis of prognostic factors in patients with adult T-cell leukemia/lymphoma

Abstract

8575 Background: Adult T-cell leukemia/lymphoma (ATLL) is associated with human T-cell lymphotropic virus type-I (HTLV-1) described in Southern Japan, Europe, Caribbean and South America. Risk-stratification tools for ATLL have not been adequately evaluated. This study attempts to define prognostic factors for patients with ATLL. Methods: A total of 102 cases from our Institution were collected between January 1997 and September 2008. Diagnosis was based on clinical history and histological findings consistent with ATLL and either positive HTLV-1 serology or evidence of HTLV-1 integration. Survival curves were estimated using the Kaplan-Meier method. Univariate and multivariate analyses were evaluated using log-rank and Cox regression tests, respectively. Results: Median age was 61 years with a female:male ratio of 1.15:1. Clinical types were acute (n=45), lymphomatous (n=43), cutaneous (n=10), smoldering (n=3) and chronic (n=1). Median OS for acute, lymphomatous, smoldering and cutaneous subtype were 2, 11, 17 and 39 months, respectively (log-rank 28.5, p<0.00001). In the univariate analysis, presence of B symptoms, ECOG performance status 2, clinical stage II or higher, elevated LDH level and bone marrow (BM) involvement were independent factors for survival with p<0.05. The IPI score was available in 92 patients; 13 (14%), 12 (13%), 29 (32%) and 38 (41%) patients were low, low-intermediate, high-intermediate and high-risk, respectively. Median OS by IPI risk group was 40, 13, 6 and 2 months, respectively (p<0.005). The prognostic index for T-cell lymphoma (PIT) score was determined in 80 patients; 20 (25%), 17 (21%), 33 (41%) and 10 (13%) patients had scores of 0–1, 2, 3 and 4, respectively. Median OS by PIT risk group was 19, 5, 3 and 2 months, respectively (p<0.005). In multivariate analysis, BM involvement and elevated LDH were significant for survival. Conclusions: This retrospective series represents the largest Latin-American experience on ATLL, which is a heterogeneous disease with distinct clinical features and outcomes. The IPI ant PIT scores, used for risk-stratification of aggressive B-cell and peripheral T-cell lymphomas, respectively, appear as good prognostic indicators for ATLL as well. Further research is needed to better risk-stratify this unique lymphoma. No significant financial relationships to disclose.