A Descriptive Study of 103 Primary Cutaneous B-Cell Lymphomas: Clinical and Pathological Characteristics and Treatment from the Spanish Lymphoma Oncology Group (GOTEL).

Primary cutaneous B-cell lymphomas (PCBCLs) are B-cell lymphomas that can occur in the skin without evidence of extracutaneous involvement. The 2005 WHO/EORTC classification of cutaneous lymphomas and its 2018 update have distinguished three main categories based on clinicopathological, immunohistochemical, and genetic characteristics: primary cutaneous marginal zone lymphoma (PCMZL), primary cutaneous follicle centre lymphoma (PCFCL), and primary cutaneous diffuse large B-cell lymphoma, leg type (PCDLBCL-LT). PCMZL and PCFCL are clinically indolent, while PCDLBCL-LT is an aggressive lymphoma. Due to its low incidence and lack of prospective studies, it is difficult to establish a standard treatment for each subgroup. The objective of our study was to describe the clinical and pathological characteristics of 103 patients with cutaneous B-cell lymphoma from 12 centres belonging to the Spanish Lymphoma Oncology Group. The median age was 53 years (40-65). According to skin extension, 62% had single-site lymphoma, 17% had regional lymphoma, and 20% had multifocal lymphoma. Histology: 66% had PCMZL, 26% had PCFCL, and 8% had PCDLBCL-LT. Twenty-three percent of the patients were treated exclusively with surgery, 26% with radiotherapy only, 21% with surgery plus radiotherapy, 10% with polychemotherapy, and 5% with rituximab monotherapy. Overall, 96% of patients achieved a complete response, and 44% subsequently relapsed, most of them relapsing either locally or regionally. The 10-year OS was 94.5% for the entire cohort, 98% for the PCMZL cohort, 95% for the PCFCL cohort, and 85.7% for the PCDLBCL-LT cohort. Our data are comparable to those of other published series, except for the high frequency of PCMZL. The expected heterogeneity in therapeutic management has been observed.

CD8+ NKs as a potential biomarker of complete response and survival with lenalidomide plus R-GDP in the R2-GDP-GOTEL trial in recurrent/refractory diffuse large B cell lymphoma.

Background: Diffuse large B cell lymphoma (DLBCL) is the most common non-Hodgkin lymphoma worldwide. DLBCL is an aggressive disease that can be cured with upfront standard chemoimmunotherapy schedules. However, in approximately 35-40% of the patients DLBCL relapses, and therefore, especially in this setting, the search for new prognostic and predictive biomarkers is an urgent need. Natural killer (NK) are effector cells characterized by playing an important role in antitumor immunity due to their cytotoxic capacity and a subset of circulating NK that express CD8 have a higher cytotoxic function. In this substudy of the R2-GDP-GOTEL trial, we have evaluated blood CD8+ NK cells as a predictor of treatment response and survival in relapsed/refractory (R/R) DLBCL patients. Methods: 78 patients received the R2-GDP schedule in the phase II trial. Blood samples were analyzed by flow cytometry. Statistical analyses were carried out in order to identify the prognostic potential of CD8+ NKs at baseline in R/R DLBCL patients. Results: Our results showed that the number of circulating CD8+ NKs in R/R DLBCL patients were lower than in healthy donors, and it did not change during and after treatment. Nevertheless, the level of blood CD8+ NKs at baseline was associated with complete responses in patients with R/R DLBCL. In addition, we also demonstrated that CD8+ NKs levels have potential prognostic value in terms of overall survival in R/R DLBCL patients. Conclusion: CD8+ NKs represent a new biomarker with prediction and prognosis potential to be considered in the clinical management of patients with R/R DLBCL. Clinical trial registration: https://www.clinicaltrialsregister.eu/ctr-search/search?query=2014-001620-29 EudraCT, ID:2014-001620-29.

18F-FDG-PET/CT response after first-line treatment as a prognostic factor for survival in peripheral T-cell lymphoma: a Spanish retrospective study.

BACKGROUND: An accurate assessment of tumor viability after first-line treatment is critical for predicting treatment failure in peripheral T-cell lymphomas (PTCLs). 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) has been adopted as the preferred assessment method in clinical trials, but its impact in clinical practice should be examined. This study aims to determine the prognostic significance of18F-FDG-PET/CT for survival following first-line treatment in PTCL patients. RESEARCH DESIGN AND METHODS: Retrospective observational study including 175 patients diagnosed with PTCL between 2008 and 2013 in 13 Spanish sites. RESULTS: Fifty patients were evaluated with18F-FDG-PET/CT following first-line therapy: 58% were18F-FDG-PET/CT-negative and 42% were18F-FDG-PET/CT-positive. Disease progression occurred in 37.9% of18F-FDG-PET/CT-negative patients and in 80.9% of18F-FDG-PET/CT-positive patients (p = 0.0037). Median progression-free survival and overall survival were 67 and 74 months for18F-FDG-PET/CT-negative patients, and 5 (p < 0.0001) and 10 months (p < 0.0001), respectively, in18F-FDG-PET/CT-positive patients. After multivariate analysis, only B symptoms emerged as a negative predictive factor of complete response (RR 7.08; 95% CI 1.60-31.31; p = 0.001). CONCLUSIONS: 18F-FDG-PET/CT identifies high-risk PTCL patients who will have poor prognosis and survival following first-line treatment. However, more research is needed to confirm the best treatment options for PTCL patients.

SEOM-GOTEL clinical guidelines on diffuse large B cell lymphoma (2022)

Diffuse large B-cell lymphoma is the most frequent histological subtype of NHL and the paradigm for the management of aggressive lymphoma. An excisional or incisional lymph node biopsy evaluated by an experienced hemopathologist is recommended to establish the diagnosis. Twenty years following its introduction, R-CHOP remains the standard first-line treatment. No modification of this scheme (increased chemotherapy dose intensity, new monoclonal antibodies, or the addition of immunomodulators or anti-target agents) has significatively improved the clinical outcomes, whereas therapy for recurrence or progression is evolving rapidly. The irruption of CART cells, polatuzumab vedotin, tafasitamab, and CD20/CD3 bispecific antibodies are changing the natural history of relapsed patients and will challenge R-CHOP as the benchmark for newly diagnosed patients (AU)

Peripheral T-cell lymphoma with a T follicular-helper phenotype: A different entity? Results of the Spanish Real-T study.

Nodal peripheral T-cell lymphoma (PTCL) with a T follicular helper phenotype (PTCL-TFH) is a new type of PTCL. We aimed to define its clinical characteristics and prognosis compared to PTCL not otherwise specified (PTCL-NOS) and angioimmunoblastic T-cell lymphoma (AITL). This retrospective observational study included 175 patients diagnosed with PTCL between 2008 and 2013 in 13 Spanish sites. Patient diagnosis was centrally reviewed, and patients were reclassified according to the World Health Organization (WHO) 2016 criteria: 21 patients as PTCL-NOS, 55 as AITL and 23 as PTCL-TFH. Median follow-up was 56.07 months (95% CI 38.7-73.4). Progression-free survival (PFS) and overall survival (OS) were significantly higher in patients with PTCL-TFH than in those with PTCL-NOS and AITL (PFS, 24.6 months vs. 4.6 and 7.8 months, respectively, p = 0.002; OS, 52.6 months vs. 10.0 and 19.3 months, respectively, p < 0.001). Histological diagnosis maintained an independent influence on both PFS (hazard ratio [HR] 4.1 vs. PTCL-NOS, p = 0.008; HR 2.6 vs. AITL, p = 0.047) and OS (HR 5.7 vs. PTCL-NOS, p = 0.004; HR 2.6 vs. AITL, p = 0.096), regardless of the International Prognostic Index. These results suggest that PTCL-TFH could have more favourable features and prognosis than the other PTCL subtypes, although larger series are needed to corroborate these findings.

SEOM-GOTEL clinical guidelines on diffuse large B cell lymphoma (2022).

Diffuse large B-cell lymphoma is the most frequent histological subtype of NHL and the paradigm for the management of aggressive lymphoma. An excisional or incisional lymph node biopsy evaluated by an experienced hemopathologist is recommended to establish the diagnosis. Twenty years following its introduction, R-CHOP remains the standard first-line treatment. No modification of this scheme (increased chemotherapy dose intensity, new monoclonal antibodies, or the addition of immunomodulators or anti-target agents) has significatively improved the clinical outcomes, whereas therapy for recurrence or progression is evolving rapidly. The irruption of CART cells, polatuzumab vedotin, tafasitamab, and CD20/CD3 bispecific antibodies are changing the natural history of relapsed patients and will challenge R-CHOP as the benchmark for newly diagnosed patients.

Impact of Molecular Testing Using Next-Generation Sequencing in the Clinical Management of Patients with Non-Small Cell Lung Cancer in a Public Healthcare Hospital.

Next-generation sequencing (NGS) is a molecular approach able to provide a comprehensive molecular profile of non-small cell lung cancer (NSCLC). The broad spectrum of biomarker-guided therapies has positioned molecular diagnostic laboratories as a central component of patient clinical management. Here, we show the results of an UNE-EN ISO 15189:2022 NGS-accredited assay in a cohort of 350 patients. TP53 (51.0%), KRAS (26.6%) and EGFR (12.9%) were the most frequently mutated genes. Furthermore, we detected co-occurring and mutually exclusive alterations, as well as distinct molecular profiles according to sex and smoking habits. Actionable genetic alterations were significantly more frequent in female patients (80.5%, p < 0.001) and in never-smoker patients (87.7%, p < 0.001). When NGS was established as the main molecular testing strategy, 36.4% of patients received at least one line of targeted treatment. Among 200 patients with stage IV NSCLC, first-line treatment with targeted therapies was associated with a longer progression-free survival (PFS) (13.4 months (95% CI, 10.2-16.6) (p = 0.001)). Similarly, the overall survival (OS) of patients receiving at least one targeted drug was significantly longer (26.2 months (95% CI, 11.8-40.5) (p < 0.001)). Our results show that the implementation of NGS in the public healthcare system has provided a broader application of precision medicine.

Technical Validation and Clinical Implications of Ultrasensitive PCR Approaches for EGFR-Thr790Met Mutation Detection in Pretreatment FFPE Samples and in Liquid Biopsies from Non-Small Cell Lung Cancer Patients.

In pretreatment tumor samples of EGFR-mutated non-small cell lung cancer (NSCLC) patients, EGFR-Thr790Met mutation has been detected in a variable prevalence by different ultrasensitive assays with controversial prognostic value. Furthermore, its detection in liquid biopsy (LB) samples remains challenging, being hampered by the shortage of circulating tumor DNA (ctDNA). Here, we describe the technical validation and clinical implications of a real-time PCR with peptide nucleic acid (PNA-Clamp) and digital droplet PCR (ddPCR) for EGFR-Thr790Met detection in diagnosis FFPE samples and in LB. Limit of blank (LOB) and limit of detection (LOD) were established by analyzing negative and low variant allele frequency (VAF) FFPE and LB specimens. In a cohort of 78 FFPE samples, both techniques showed an overall agreement (OA) of 94.20%. EGFR-Thr790Met was detected in 26.47% of cases and was associated with better progression-free survival (PFS) (16.83 ± 7.76 vs. 11.47 ± 1.83 months; p = 0.047). In LB, ddPCR was implemented in routine diagnostics under UNE-EN ISO 15189:2013 accreditation, increasing the detection rate of 32.43% by conventional methods up to 45.95%. During follow-up, ddPCR detected EGFR-Thr790Met up to 7 months before radiological progression. Extensively validated ultrasensitive assays might decipher the utility of pretreatment EGFR-Thr790Met and improve its detection rate in LB studies, even anticipating radiological progression.

Lenalidomide plus R-GDP (R2-GDP) in Relapsed/Refractory Diffuse Large B-Cell Lymphoma: Final Results of the R2-GDP-GOTEL Trial and Immune Biomarker Subanalysis.

PURPOSE: New therapeutic options are needed in relapsed/refractory diffuse large B-cell lymphoma (R/R DLBCL). Lenalidomide-based schedules can reverse rituximab refractoriness in lymphoma. PATIENTS AND METHODS: In the phase II R2-GDP trial, 78 patients unsuitable for autologous stem cell transplant received treatment with the following schedule: lenalidomide 10 mg Days (D)1-14, rituximab 375 mg/m2 D1, cisplatin 60 mg/m2 D1, gemcitabine 750 mg/m2 D1 and D8, and dexamethasone 20 mg D1-3, up to 6 cycles (induction phase), followed by lenalidomide 10 mg (or last lenalidomide dose received) D1-21 every 28 days (maintenance phase). Primary endpoint was overall response rate (ORR). Secondary endpoints included progression-free survival (PFS), overall survival (OS), safety, and monitorization of key circulating immune biomarkers (EU Clinical Trials Register number: EudraCT 2014-001620-29). RESULTS: After a median follow-up of 37 months, ORR was 60.2% [37.1% complete responses (CR) and 23.1% partial responses (PR)]. Median OS was 12 months (47 vs. 6 months in CR vs. no CR); median PFS was 9 months (34 vs. 5 months in CR vs. no CR). In the primary refractory population, ORR was 45.5% (21.2% CR and 24.3% PR). Most common grade 3-4 adverse events were thrombocytopenia (60.2%), neutropenia (60.2%), anemia (26.9%), infections (15.3%), and febrile neutropenia (14.1%). Complete responses were associated with a sharp decrease in circulating myeloid-derived suppressor cells and regulatory T cells. CONCLUSIONS: R2-GDP schedule is feasible and highly active in R/R DLBCL, including the primary refractory population. Immune biomarkers showed differences in responders versus progressors.

Circulating myeloid-derived suppressor cells and regulatory T cells as immunological biomarkers in refractory/relapsed diffuse large B-cell lymphoma: translational results from the R2-GDP-GOTEL trial.

BACKGROUND: The search for immunological markers with ability of predicting clinical outcome is a priority in lymphomas, and in cancer in general. It is well known that some immunomodulatory cells, such as myeloid derived suppressor cells (MDSCs) or regulatory T cells (Tregs), are recruited by tumors, jeopardizing antitumor immunosurveillance. In this work, we have studied blood levels of these immunosuppressive cells in patients with relapsed/refractory diffuse large B-cell lymphoma (R/R DLBCL), prior to and along the course of the experimental rituximab, gemcitabine, dexamethasone, and cisplatin (R2-GDP) schedule, as a translational substudy of the R2-GDP-GOTEL trial (EudraCT Number: 2014-001620-29), which included lenalidomide as an immunomodulator. METHODS: Blood samples were taken before treatment, at cycle 3 and end of induction. Samples were analyzed by flow cytometry. Non-parametric tests were used. Mann-Whitney U test was used to compare basal cells distributions, and Wilcoxon test was considered to compare cells distribution at different times. Spearman test was performed to measure the degree of association between cell populations. RESULTS: In this study, MDSC and Treg circulating concentration was found increased in all patients compared with a healthy control group and decreased after treatment only in patients with longest overall survival (>24 months), reaching the levels of the healthy group. Likewise, the number of inhibited T lymphocytes expressing Programmed Death-1 (PD-1) were increased in peripheral blood from patients and decreased on the treatment, whereas activated T lymphocytes increased after therapy in those with better overall survival. CONCLUSIONS: In conclusion, blood concentration of MDSCs and Treg cells may be good prognostic markers for overall survival after 2 years in R/R DLBCL. These results point to a possible role of these elements in the immunosuppression of these patients, as assessed by the circulating activated and inhibited T lymphocytes, and therefore, they may be considered as therapeutic targets in DLBCL.

Multicenter Study of the Seroprevalence of Antibodies against Covid-19 in Patients with Lymphoma: An Analysis of the Oncological Group for the Treatment and Study of Lymphomas (Gotel).

The new Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) coronavirus has generated a pandemic, in which there are population groups at higher risk and who are potentially fatal victims of the disease. Cancer patients have been considered a group with special susceptibility, particularly patients with lung tumour involvement and haematological neoplasms. The Spanish Lymphoma Oncology Group (GOTEL) carried out a multicenter study of SARS-CoV-2 seroprevalence in patients with lymphoma. Results: A total of 150 patients were included between 22 May and 11 June 2020. The mean age was 65 years (range 17-89), 70 women (46.5%) and 80 men (53, 5%). At the time of diagnosis of lymphoma, 13 cases were stage I (9%), 27 (18%) stage II, 37 (24.5%) stage III, and 73 (48.5%) stage IV, while 6.6% had a primary extranodal origin. A total of 10 cases with positive serology for SARS-CoV-2 were identified, which is a prevalence of 6% in this population. None of the patients required intensive care unit management and all fully recovered from the infection. Conclusion: IgG antibody seroprevalence in lymphoma patients appears similar to that of the general population and does not show greater aggressiveness.

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.

Long-term follow-up of a prospective phase 2 clinical trial of extended treatment with rituximab in patients with B cell post-transplant lymphoproliferative disease and validation in real world patients.

The purpose of this report is to provide long-term follow-up of 38 patients diagnosed of post-transplant lymphoproliferative disease (PTLD) included in a phase 2 clinical trial of first line therapy with rituximab and to evaluate the same therapy in a real world cohort of 21 consecutive patients treated once the trial was closed. Eligible patients were ≥ 18 years of age with a biopsy-proven CD20 positive B cell PTLD and treatment naive except for reduction of immunosuppression. Treatment consisted in four weekly infusions of rituximab at the standard dose of 375 mg/m2. Patients in complete remission (CR) were followed without further treatment, and those in partial remission (PR) were treated with another four cycles of weekly rituximab. Median follow-up in the clinical trial was 13.0 years. Disease-specific survival (DSS) at 10 years was 64.7% [95% confidence interval (CI) 48.2-81.2%]. For those patients who achieved CR (61%), DSS at 5 and 10 years was 94.4% (95% CI 83.8-100%) and 88.1% (95% CI 72.6-100%), respectively, and only 1 patient progressed beyond 5 years. The median follow-up of the real world patients was 6.5 years. DSS at 5 years was 75.2% (95% CI 56.4-94.0%). DSS at 5 years of patients who achieved CR (38%) was 87.5% (95% CI 64.6-100%). In conclusion, PTLD patients in CR after rituximab have an excellent long-term outcome. These results not only apply in the clinical trial setting but are also reproducible in the real world. However, those patients who do not respond represent an unmet clinical need and should be included in prospective clinical trials.

Clinical and pathological characteristics of peripheral T-cell lymphomas in a Spanish population: a retrospective study.

We investigated the clinicopathological features and prognostic factors of patients with peripheral T-cell lymphoma (PTCL) in 13 sites across Spain. Relevant clinical antecedents, CD30 expression and staining pattern, prognostic indices using the International Prognostic Index and the Intergruppo Italiano Linfomi system, treatments, and clinical outcomes were examined. A sizeable proportion of 175 patients had a history of immune-related disorders (autoimmune 16%, viral infections 17%, chemo/radiotherapy-treated carcinomas 19%). The median progression-free survival (PFS) and overall survival (OS) were 7·9 and 15·8 months, respectively. Prognostic indices influenced PFS and OS, with a higher number of adverse factors resulting in shorter survival (P < 0·001). Complete response (CR) to treatment was associated with better PFS (62·6 vs. 4 months; P < 0·001) and longer OS (67·0 vs. 7·3 months; P < 0·001) compared to no CR. CD30 was expressed across all subtypes; >15% of cells were positive in anaplastic lymphoma kinase-positive and -negative anaplastic large-cell lymphoma and extranodal natural killer PTCL groups. We observed PTCL distribution across subtypes based on haematopathological re-evaluation. Poor prognosis, effect of specific prognostic indices, relevance of histopathological sub-classification, and response level to first-line treatment on outcomes were confirmed. Immune disorders amongst patients require further examination involving genetic studies and identification of associated immunosuppressive factors.

Oral vinorelbine versus etoposide with cisplatin and chemo-radiation as treatment in patients with stage III non-small cell lung cancer: A randomized phase II (RENO study).

OBJECTIVES: Concomitant chemo-radiation is the standard treatment for unresectable stage III non-small cell lung cancer (LA-NSCLC). The aim of this study was to assess the safety and efficacy of oral vinorelbine and cisplatin (OVP) compared with etoposide and cisplatin (EP), both in combination with radiotherapy, in this setting. MATERIAL AND METHODS: An open-label, randomized phase II trial was undertaken including 23 hospitals in Spain. Adults with untreated unresectable stage III NSCLC were randomized1:1 to receive: oral vinorelbine (days 1 and 8 with cisplatin on day 1 in 3-week cycles; 2 cycles of induction, 2 cycles in concomitance) or etoposide (days 1-5 and 29-32 with cisplatin on days 1 and 8 in 4-week cycles; 2 cycles in concomitance). Both groups received concomitant radiotherapy 2 Gy/day (66 Gy). The primary endpoint was progression free survival (PFS). RESULTS: One hundred and forty patients were enrolled. Sixty-nine patients received OVP and 71 received EP. Globally adverse events grade 3/4 per cycle were fewer in the vinorelbine arm (19.4%) than in the etoposide arm (62.6%) (p < 0.001). One patient (1.5%) in the OVP arm and 12 pts (17.6%) in the EP arm presented esophagitis grade 3/4 (p = 0.002). Median PFS was similar in both groups (10.8 [95% CI 7.7-13.8] and 9.6 months [95% CI 4.4-14.8]; p = 0.457, respectively). Preliminary median overall survival was 30 months in the OVP arm and 31.9 months in the EP arm (p = 0.688). CONCLUSIONS: Our findings show that OVP could be considered a standard combination with similar efficacy and better safety profile for the treatment of LA-NSCLC patients.

Development, Implementation and Assessment of Molecular Diagnostics by Next Generation Sequencing in Personalized Treatment of Cancer: Experience of a Public Reference Healthcare Hospital.

The establishment of precision medicine in cancer patients requires the study of several biomarkers. Single-gene testing approaches are limited by sample availability and turnaround time. Next generation sequencing (NGS) provides an alternative for detecting genetic alterations in several genes with low sample requirements. Here we show the implementation to routine diagnostics of a NGS assay under International Organization for Standardization (UNE-EN ISO 15189:2013) accreditation. For this purpose, 106 non-small cell lung cancer (NSCLC) and 102 metastatic colorectal cancer (mCRC) specimens were selected for NGS analysis with Oncomine Solid Tumor (ThermoFisher). In NSCLC the most prevalently mutated gene was TP53 (49%), followed by KRAS (31%) and EGFR (13%); in mCRC, TP53 (50%), KRAS (48%) and PIK3CA (16%) were the most frequently mutated genes. Moreover, NGS identified actionable genetic alterations in 58% of NSCLC patients, and 49% of mCRC patients did not harbor primary resistance mechanisms to anti-EGFR treatment. Validation with conventional approaches showed an overall agreement >90%. Turnaround time and cost analysis revealed that NGS implementation is feasible in the public healthcare context. Therefore, NGS is a multiplexed molecular diagnostic tool able to overcome the limitations of current molecular diagnosis in advanced cancer, allowing an improved and economically sustainable molecular profiling.

Transformed follicular lymphoma in the rituximab era: A report from the Spanish Lymphoma Oncology Group.

Follicular lymphoma (FL) is the second most common non-Hodgkin lymphoma (NHL) subtype. The histological transformation (HT) of FL is an event considered frequent in the natural history of this tumor. We studied the transformation rates, predictive factors, and treatment characteristics that may impact in the survival of patients with FL and HT. A total of 1074 patients diagnosed with FL were prospectively enrolled from 1990 to 2016 in a Spanish registry. Sixty-four HTs were recorded based on clinical criteria (55%) or histological confirmation (45%). The cumulative incidence rate of transformation at 5 years is 7.3%. The 5-year overall survival (OS) without HT was 85% (95% confidence interval [CI], 70%-90%) vs 66% (95% CI, 51%-76%; P = 0.0012) with HT. Factors associated with HT were elevated lactate dehydrogenase (LDH) (odds ratio [OR] 1.83), intermediate-high Follicular lymphoma international prognostic index (FLIPI) (OR 2.16-OR 3.21), B symptoms (OR 2.46), or Eastern Cooperative Oncology Group (ECOG) 1 (OR 2.35). Treatment options related to HT were "watch and wait" or no rituximab or anthracyclines initially. A 5-year OS for patients treated with chemotherapy before HT was 55% (95% CI, 38%-69%) versus 81% (95% CI, 53%-93%; P = 0.009) for those who had not received it. The HT rate has decreased after the introduction of rituximab, as has been previously described. The timing of this treatment had an impact on the survival of these patients.

Unraveling transformation of follicular lymphoma to diffuse large B-cell lymphoma.

Follicular lymphoma (FL) is an indolent but largely incurable disease. Some patients suffer histological transformation to a more aggressive subtype with poorer prognosis. This study aimed to improve our understanding of the genetics underlying FL histological transformation, and to identify genetic drivers or promoters of the transformation by elucidating the differences between FL samples from patients who did and did not transform. We conducted targeted massive parallel sequencing of 22 pre-transformed FL/transformed diffuse large B-cell lymphoma pairs and 20 diagnostic samples from non-transformed FL patients. Additionally, 22 matched samples from 11 transformed FL patients (pre-transformed FL and diffuse large B-cell lymphoma) and 9 non-transformed FLs were studied for copy number variation using SNP arrays. We identified recurrently mutated genes that were enriched at transformation, most notably LRP1B, GNA13 and POU2AF1, which have roles in B-cell differentiation, GC architecture and migration. Mutations in POU2AF1 might be associated with lower levels of expression, were more frequent in transformed FLs, and seemed to be specific to transformed- compared with de novo-diffuse large B-cell lymphomas. Pre-transformed FLs carried more mutations per sample and had greater subclonal heterogeneity than non-transformed FLs. Finally, we identified four mutated genes in FL samples that differed between patients who did and did not transform: NOTCH2, DTX1, UBE2A and HIST1H1E. The presence of mutations in these genes was associated with shorter time to transformation when mutated in the FL biopsies. This information might be useful for identifying patients at higher risk of transformation.

Post-transplant lymphoproliferative disorders after solid organ and hematopoietic stem cell transplantation.

Post-transplant lymphoproliferative disorders (PTLD) are a rare complication after both solid organ (SOT) and allogeneic hematopoietic stem cell transplantation (allo-HSCT). In this single center retrospective study, we compared clinical, biological, and histological features, and outcomes of PTLD after both types of transplant. We identified 82 PTLD (61 after SOT and 21 after allo-HSCT). The presence of B symptoms, Waldeyer ring, spleen, central nervous system, and liver involvement, and advanced Ann-Arbor stage were more frequent in allo-HSCT recipients. PTLD had an earlier onset in allo-HSCT than in SOT cohort (4 vs. 64 months, p < .0001). PTLD was EBV-positive in 100% of allo-HSCT, in contrast to 47% of SOT (p = .0002). Four years after PTLD diagnosis, median overall survival was 32% (95% CI, 22-48) and 10% (95% CI, 2-49) in SOT and allo-HSCT recipients, respectively (p = .002). In conclusion, the clinical presentation and the outcome of PTLD varies greatly depending on the type of transplant.