Martin Bast

BACKGROUND: Despite advances in treatments for Hodgkin's lymphoma, about 20% of patients still die from progressive disease. Current prognostic models predict the outcome of treatment with imperfect accuracy, and clinically relevant biomarkers have not been established to improve on the International Prognostic Score. METHODS: Using gene-expression profiling, we analyzed 130 frozen samples obtained from patients with classic Hodgkin's lymphoma during diagnostic lymph-node biopsy to determine which cellular signatures were correlated with treatment outcome. We confirmed our findings in an independent cohort of 166 patients, using immunohistochemical analysis. RESULTS: Gene-expression profiling identified a gene signature of tumor-associated macrophages that was significantly associated with primary treatment failure (P=0.02). In an independent cohort of patients, we found that an increased number of CD68+ macrophages was correlated with a shortened progression-free survival (P=0.03) and with an increased likelihood of relapse after autologous hematopoietic stem-cell transplantation (P=0.008), resulting in shortened disease-specific survival (P=0.003). In multivariate analysis, this adverse prognostic factor outperformed the International Prognostic Score for disease-specific survival (P=0.003 vs. P=0.03). The absence of an elevated number of CD68+ cells in patients with limited-stage disease defined a subgroup of patients with a long-term disease-specific survival of 100% with the use of current treatment strategies. CONCLUSIONS: An increased number of tumor-associated macrophages was strongly associated with shortened survival in patients with classic Hodgkin's lymphoma and provides a new biomarker for risk stratification.

BACKGROUND: The distinction between Burkitt's lymphoma and diffuse large-B-cell lymphoma is crucial because these two types of lymphoma require different treatments. We examined whether gene-expression profiling could reliably distinguish Burkitt's lymphoma from diffuse large-B-cell lymphoma. METHODS: Tumor-biopsy specimens from 303 patients with aggressive lymphomas were profiled for gene expression and were also classified according to morphology, immunohistochemistry, and detection of the t(8;14) c-myc translocation. RESULTS: A classifier based on gene expression correctly identified all 25 pathologically verified cases of classic Burkitt's lymphoma. Burkitt's lymphoma was readily distinguished from diffuse large-B-cell lymphoma by the high level of expression of c-myc target genes, the expression of a subgroup of germinal-center B-cell genes, and the low level of expression of major-histocompatibility-complex class I genes and nuclear factor-kappaB target genes. Eight specimens with a pathological diagnosis of diffuse large-B-cell lymphoma had the typical gene-expression profile of Burkitt's lymphoma, suggesting they represent cases of Burkitt's lymphoma that are difficult to diagnose by current methods. Among 28 of the patients with a molecular diagnosis of Burkitt's lymphoma, the overall survival was superior among those who had received intensive chemotherapy regimens instead of lower-dose regimens. CONCLUSIONS: Gene-expression profiling is an accurate, quantitative method for distinguishing Burkitt's lymphoma from diffuse large-B-cell lymphoma.

PURPOSE: The heterogeneity of diffuse large B-cell lymphoma (DLBCL) has prompted the search for new markers that can accurately separate prognostic risk groups. We previously showed in a multivariate model that LMO2 mRNA was a strong predictor of superior outcome in DLBCL patients. Here, we tested the prognostic impact of LMO2 protein expression in DLBCL patients treated with anthracycline-based chemotherapy with or without rituximab. PATIENTS AND METHODS: DLBCL patients treated with anthracycline-based chemotherapy alone (263 patients) or with the addition of rituximab (80 patients) were studied using immunohistochemistry for LMO2 on tissue microarrays of original biopsies. Staining results were correlated with outcome. RESULTS: In anthracycline-treated patients, LMO2 protein expression was significantly correlated with improved overall survival (OS) and progression-free survival (PFS) in univariate analyses (OS, P = .018; PFS, P = .010) and was a significant predictor independent of the clinical International Prognostic Index (IPI) in multivariate analysis. Similarly, in patients treated with the combination of anthracycline-containing regimens and rituximab, LMO2 protein expression was also significantly correlated with improved OS and PFS (OS, P = .005; PFS, P = .009) and was a significant predictor independent of the IPI in multivariate analysis. CONCLUSION: We conclude that LMO2 protein expression is a prognostic marker in DLBCL patients treated with anthracycline-based regimens alone or in combination with rituximab. After further validation, immunohistologic analysis of LMO2 protein expression may become a practical assay for newly diagnosed DLBCL patients to optimize their clinical management.

Purpose Patients with double-hit lymphoma (DHL) rarely achieve long-term survival following disease relapse. Some patients with DHL undergo consolidative autologous stem-cell transplantation (autoSCT) to reduce the risk of relapse, although the benefit of this treatment strategy is unclear. Methods Patients with DHL who achieved first complete remission following completion of front-line therapy with either rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) or intensive front-line therapy, and deemed fit for autoSCT, were included. A landmark analysis was performed, with time zero defined as 3 months after completion of front-line therapy. Patients who experienced relapse before or who were not followed until that time were excluded. Results Relapse-free survival (RFS) and overall survival (OS) rates at 3 years were 80% and 87%, respectively, for all patients (n = 159). Three-year RFS and OS rates did not differ significantly for autoSCT (n = 62) versus non-autoSCT patients (n = 97), but 3-year RFS was inferior in patients who received R-CHOP compared with intensive therapy (56% v 88%; P = .002). Three-year RFS and OS did not differ significantly for patients in the R-CHOP or intensive therapy cohorts when analyzed by receipt of autoSCT. The median OS following relapse was 8.6 months. Conclusion In the largest reported series, to our knowledge, of patients with DHL to achieve first complete remission, consolidative autoSCT was not associated with improved 3-year RFS or OS. In addition, patients treated with R-CHOP experienced inferior 3-year RFS compared with those who received intensive front-line therapy. When considered in conjunction with reports of patients with newly diagnosed DHL, which demonstrate lower rates of disease response to R-CHOP compared with intensive front-line therapy, our findings further support the use of intensive front-line therapy for this patient population.

Peripheral T-cell lymphoma is the most common type of T-cell lymphoma seen in adults in the United States. Clinical data were reviewed from 134 cases of peripheral T-cell lymphoma diagnosed in three centers. The median age of the patients was 57 years (range, 4-97 years), 59% were male, and 36 patients (27%) had a history of a preceding disorder of the immune system. The tumors were grouped histologically into large cell (43%), mixed large and small cell (40%), and small cell (17%). The stage at diagnosis was I (7%), II (21%), III (22%), and IV (50%). B symptoms were present in 57%. The most frequent sites of extranodal involvement were bone marrow (35%), skin (13%), and lung (11%). Eighty patients were treated with a multiagent chemotherapy regimen with proven curative potential in aggressive non-Hodgkin's lymphomas and the remainder of the patients received less intensive chemotherapy (36 patients), radiotherapy (nine patients), or no treatment (nine patients). Fifty percent of the intensively treated patients achieved complete remission and the actuarial 4-year survival was 45%. However, the 4-year, disease-free survival in patients with Stage IV disease was only 10%. Although peripheral T-cell lymphomas appeared similar in many ways to their B-cell counterparts, disease-free survival by stage was low and patients with Stage IV disease had an especially poor outlook.