Clinicobiological features and prognostic impact of diffuse large B-cell lymphoma component in the outcome of patients with previously untreated follicular lymphoma.

BACKGROUND: The co-existence at diagnosis of follicular lymphoma (FL) and diffuse large B-cell lymphoma (DLBCL) components (FL/DLBCL) has been considered a transformed lymphoma and accordingly treated although clinicobiological information on these patients is scarce. The aim of this study was to analyze the initial features and outcome of FL/DLBCL patients in the rituximab era. PATIENTS AND METHODS: All patients consecutively diagnosed at a single institution with FL/DLBCL (n = 40), as well as those with pure FL (n = 328) or de novo DLBCL (n = 510) as controls. RESULTS: The proportion of the DLBCL component was highly variable (median 50%). In 29 FL/DLBCL cases analyzed, the cell of origin was GCB in 86%, ABC in 10% and unclassifiable in 4%. NOTCH1-2 was mutated in 10% of these cases. The proportion of DLBCL component did not impact on overall survival (OS). Regarding initial characteristics, patients with FL/DLBCL were closer to FL in terms of primary nodal origin, good performance status and advanced stage, whereas the other features were intermediate between FL and DLBCL. FL/DLBCL patients were treated as DLBCL with no further intensification. Complete response and primary refractory rates were 65% and 20%, respectively, with these figures being similar to DLBCL and worse than FL. Progression-free survival and OS were intermediate between FL and DLBCL (5-year OS: 85%, 73% and 63% for FL, FL/DLBCL and DLBCL, respectively). FL/DLBCL histology did not reach independent prognostic value for OS in the multivariate analyses. CONCLUSIONS: The outcome of FL/DLBCL patients is not worse than that of de novo DLBCL. These cases should be treated with immunochemotherapy as DLBCL, but intensification with ASCT may not be necessary. The biological insights of FL/DLBCL warrants further genetic and molecular studies.

A B-cell epigenetic signature defines three biologic subgroups of chronic lymphocytic leukemia with clinical impact.

Prospective identification of patients with chronic lymphocytic leukemia (CLL) destined to progress would greatly facilitate their clinical management. Recently, whole-genome DNA methylation analyses identified three clinicobiologic CLL subgroups with an epigenetic signature related to different normal B-cell counterparts. Here, we developed a clinically applicable method to identify these subgroups and to study their clinical relevance. Using a support vector machine approach, we built a prediction model using five epigenetic biomarkers that was able to classify CLL patients accurately into the three subgroups, namely naive B-cell-like, intermediate and memory B-cell-like CLL. DNA methylation was quantified by highly reproducible bisulfite pyrosequencing assays in two independent CLL series. In the initial series (n=211), the three subgroups showed differential levels of IGHV (immunoglobulin heavy-chain locus) mutation (P<0.001) and VH usage (P<0.03), as well as different clinical features and outcome in terms of time to first treatment (TTT) and overall survival (P<0.001). A multivariate Cox model showed that epigenetic classification was the strongest predictor of TTT (P<0.001) along with Binet stage (P<0.001). These findings were corroborated in a validation series (n=97). In this study, we developed a simple and robust method using epigenetic biomarkers to categorize CLLs into three subgroups with different clinicobiologic features and outcome.

NOTCH1 mutations identify a genetic subgroup of chronic lymphocytic leukemia patients with high risk of transformation and poor outcome.

NOTCH1 has been found recurrently mutated in a subset of patients with chronic lymphocytic leukemia (CLL). To analyze biological features and clinical impact of NOTCH1 mutations in CLL, we sequenced this gene in 565 patients. NOTCH1 mutations, found in 63 patients (11%), were associated with unmutated IGHV, high expression of CD38 and ZAP-70, trisomy 12, advanced stage and elevated lactate dehydrogenase. Sequential analysis in 200 patients demonstrated acquisition of mutation in one case (0.5%) and disappearance after treatment in two. Binet A and B patients with NOTCH1-mutated had a shorter time to treatment. NOTCH1-mutated patients were more frequently refractory to therapy and showed shorter progression-free and overall survival after complete remission. Overall survival was shorter in NOTCH1-mutated patients, although not independently from IGHV. NOTCH1 mutation increased the risk of transformation to diffuse large B-cell lymphoma independently from IGHV, with this being validated in resampling tests of replicability. In summary, NOTCH1 mutational status, that was rarely acquired during the course of the disease, identify a genetic subgroup with high risk of transformation and poor outcome. This recently identified genetic subgroup of CLL patients deserves prospective studies to define their best management.

Next-generation sequencing reveas the secrets of the chronic lymphocytic leukemia genome

The study of the detailed molecular history of cancer development is one of the most promising techniques to understand and fight this diverse and prevalent disease. Unfortunately, this history is as diverse as cancer itself. Therefore, even with next-generation sequencing techniques, it is not easy to distinguish significant (driver) from random (passenger) events. The International Cancer Genome Consortium (ICGC) was formed to solve this fundamental issue by coordinating the sequencing of samples from 50 different cancer types and/or sub-types that are of clinical and societal importance. The contribution of Spain in this consortium has been focused on chronic lymphocytic leukemia (CLL). This approach has unveiled new and unexpected events in the development of CLL. In this review, we introduce the approaches utilized by the consortium for the study of the CLL genome and discuss the recent results and future perspectives of this work (AU)

Comparison of four prognostic scores in peripheral T-cell lymphoma.

BACKGROUND: To compare the usefulness of four prognostic scores in patients with peripheral T-cell lymphoma (PTCL) from a single institution. PATIENTS AND METHODS: One hundred twenty-one patients (77 male/36 female, median age 53 years) with PTCL [anaplastic large-cell lymphoma (ALCL) 21, PTCL not otherwise specified 56 and other 44)]. Complete response (CR) rate and 5-year overall survival (OS) were 41% and 31%, respectively. International Prognostic Index (IPI), Prognostic Index for T-cell lymphoma (PIT), International peripheral T-cell lymphoma Project score (IPTCLP) and modified Prognostic Index for T-cell lymphoma (mPIT) were calculated as in the original references. mPIT was only assembled to 41 patients in whom Ki-67 immunostaining was available. ALCL patients were analyzed separately. RESULTS: Concordance among IPI, PIT and IPTCLP was 52% for low-risk group, 27% for low/intermediate-risk group, 20% for high/intermediate-risk group and 14% for high-risk group. IPI, PIT and IPTCLP predicted CR, with IPI being the best score in logistic regression. Neither Ki-67 immunostaining nor mPIT predicted CR. Five-year OS (low-risk versus intermediate- or high-risk categories) according to IPI, PIT, IPTCLP and mPIT were 52% versus 45%, 75% versus 49%, 58% versus 20% and 39% versus 0%, respectively. IPTCLP was the best score for OS in multivariate analysis. CONCLUSION: All the scores demonstrated their usefulness to assess the outcome of patients with PTCL, with IPTCLP being the most significant to predict OS.