Monitoring of Circulating Tumor DNA Predicts Response to Treatment and Early Progression in Follicular Lymphoma: Results of a Prospective Pilot Study.

PURPOSE: Follicular lymphoma (FL) is the most frequent indolent non-Hodgkin lymphoma. Around 20% of patients suffer early disease progression within 24 months (POD24) of diagnosis. This study examined the significance of circulating tumor DNA (ctDNA) in predicting response to therapy and POD24 in patients with FL. EXPERIMENTAL DESIGN: We collected 100 plasma samples, before and during the treatment, from 36 patients with FL prospectively enrolled in 8 Spanish hospitals. They were treated with a chemotherapy-rituximab regimen and followed up for a median of 3.43 years. We performed targeted deep sequencing in cell-free DNA (cfDNA) and tumor genomic DNA from 31 diagnostic biopsy samples. RESULTS: Of the alterations detected in the diagnostic tissue samples, 73% (300/411) were also identified in basal cfDNA. The mean numbers of alterations per basal cfDNA sample in patients who suffered progression of disease within 24 months (POD24-pos) or did not achieve complete response (non-CR) were significantly higher than in POD24-neg or CR patients (unpaired samples t test, P = 0.0001 and 0.001, respectively). Pretreatment ctDNA levels, as haploid genome equivalents per milliliter of plasma, were higher in patients without CR (P = 0.02) and in POD24-pos patients compared with POD24-neg patients (P < 0.001). Dynamic analysis showed that ctDNA levels decreased dramatically after treatment, although the reduction was more significant in patients with CR and POD24-neg patients. CONCLUSIONS: Basal ctDNA levels are associated with the risk of early progression and response to treatment in FL. cfDNA monitoring and genotyping during treatment and follow-up predict response to treatment and early progression.

Long-term follow-up of patients with nodular lymphocyte predominant Hodgkin lymphoma: A report from the Spanish Lymphoma Oncology Group.

Nodular lymphocytic predominance Hodgkin lymphoma (NLPHL) is a very uncommon subtype of Hodgkin lymphoma (HL), representing approximately 5% of all HL cases, with an incidence of 0.3/100,000 cases per year and with unique characteristics which distinguish it from classic Hodgkin lymphoma. Given its low frequency, there is a lack of prospective randomized studies to inform practice, the accumulated experience of academic groups being the main source of relevant information for the management of these patients. Eighty-five patients recruited by the Spanish Lymphoma Group (GOTEL) from 12 different hospitals were retrospectively analyzed to describe their sociodemographic and clinical characteristics. The median follow-up was 16 years, with a 10-year overall survive of 92.9% and 81.2% at 20 years. Five patients developed a second malignancy. No transformation to a more aggressive lymphoma was detected. A total of 31% tumor relapses was found: 77% in a single location; most of them at a supra-diaphragmatic level. Patients received different first-line treatments, and progression was observed in 3/4 (75%) of the patients who did not receive any type of treatment, 6/23 (26%) who received both chemotherapy (CH) and radiotherapy (RT), 12/43 (27%) who received RT and 7/15 (47%) that received only CH treatment. The mean time to relapse was 3 years and 47% presented relapses beyond 5 years (higher probability in stage IV p < 0.001). This is one of the longest follow-up series of NLPHL published, confirming its excellent prognosis, and that treatments may be adapted to reduce toxicity. Causes of death in these patients are varied, and the minority due to a primary malignancy relapses.

Proposal and validation of a method to classify genetic subtypes of diffuse large B cell lymphoma.

Diffuse large B-cell lymphoma (DLBCL) is a heterogeneous disease whose prognosis is associated with clinical features, cell-of-origin and genetic aberrations. Recent integrative, multi-omic analyses had led to identifying overlapping genetic DLBCL subtypes. We used targeted massive sequencing to analyze 84 diagnostic samples from a multicenter cohort of patients with DLBCL treated with rituximab-containing therapies and a median follow-up of 6 years. The most frequently mutated genes were IGLL5 (43%), KMT2D (33.3%), CREBBP (28.6%), PIM1 (26.2%), and CARD11 (22.6%). Mutations in CD79B were associated with a higher risk of relapse after treatment, whereas patients with mutations in CD79B, ETS1, and CD58 had a significantly shorter survival. Based on the new genetic DLBCL classifications, we tested and validated a simplified method to classify samples in five genetic subtypes analyzing the mutational status of 26 genes and BCL2 and BCL6 translocations. We propose a two-step genetic DLBCL classifier (2-S), integrating the most significant features from previous algorithms, to classify the samples as N12-S, EZB2-S, MCD2-S, BN22-S, and ST22-S groups. We determined its sensitivity and specificity, compared with the other established algorithms, and evaluated its clinical impact. The results showed that ST22-S is the group with the best clinical outcome and N12-S, the more aggressive one. EZB2-S identified a subgroup with a worse prognosis among GCB-DLBLC cases.

mRNA in exosomas as a liquid biopsy in non-Hodgkin Lymphoma: a multicentric study by the Spanish Lymphoma Oncology Group.

PURPOSE: To determine the feasibility of mRNAs (C-MYC, BCL-XL, BCL-6, NF-κß, PTEN and AKT) in exosomes of plasma as a liquid biopsy method for monitoring and prognostic evolution in B-cell lymphomas. PATIENTS AND METHODS: Exosomes were isolated from 98 patients with B-cell Lymphoma and 68 healthy controls. mRNAs were analyzed by quantitative PCR. An additional 31 post-treatment samples were also studied. RESULTS: In the general and follicular lymphoma series, the presence of AKT mRNA was associated with poor response to rituximab-based treatment. Patients with first relapse or disease progression showed a lower percentage of PTEN and BCL-XL mRNA. The presence of BCL-6 mRNA was associated with a high death rate. The absence of PTEN mRNA in the general series, and presence of C-MYC mRNA in follicular lymphomas, were associated with short progression-free survival. BCL-6 and C-MYC mRNA were independent prognostic variables of overall survival. C-MYC mRNA may provide prognostic information with respect to overall survival. BCL-XL mRNA and increase of BCL-6 mRNA in post-treatment samples could serve as molecular monitoring markers. CONCLUSIONS: This is the first large study to evaluate the prognostic and predictive values of pretreatment tumor-associated mRNA in exosomes. BCL-6 and C-MYC mRNA positivity in pretreatment samples were predictors of worse PFS compared to patients with mRNA negativity. C-MYC mRNA positivity was also a statistically significant predictor of inability to obtain complete response with first-line therapy.

Consolidation treatment with Yttrium-90 ibritumomab tiuxetan after new induction regimen in patients with intermediate- and high-risk follicular lymphoma according to the follicular lymphoma international prognostic index: a multicenter, prospective phase II trial of the Spanish Lymphoma Oncology Group.

Relapse is the main cause of therapeutic failure in follicular lymphoma (FL). We set out to evaluate the role of consolidation with Yttrium-90 ibritumomab tiuxetan in patients with intermediate- and high-risk FL after four cycles of CHOP-R (cyclophosphamide, doxorubicin, vincristine, prednisone, rituximab) and two cycles of CHOP. Thirty patients were included. The overall response rate after consolidation therapy was 93%. Of the 18 patients who presented with a partial response after induction treatment, 11 had a complete response after consolidation treatment. The complete clinical response rate was 76.6%. The most important grade 3-4 toxicity was hematological, with 46% thrombopenia and 56% neutropenia. With a median follow-up of 26 months, the means for progression-free survival and overall survival were not reached. Our data support consolidation with Yttrium-90 ibritumomab tiuxetan as an effective treatment, which provides long progression-free and overall survival, in first line after a response to induction treatment in patients with intermediate- and high-risk FL.