Diversity of intratumoral regulatory T cells in B-cell non-Hodgkin lymphoma.

Tumor-infiltrating regulatory T cells (Tregs) contribute to an immunosuppressive tumor microenvironment. Despite extensive studies, the prognostic impact of tumor-infiltrating Tregs in B-cell non-Hodgkin lymphomas (B-NHLs) remains unclear. Emerging studies suggest substantial heterogeneity in the phenotypes and suppressive capacities of Tregs, emphasizing the importance of understanding Treg diversity and the need for additional markers to identify highly suppressive Tregs. Here, we applied single-cell RNA sequencing and T-cell receptor sequencing combined with high-dimensional cytometry to decipher the heterogeneity of intratumoral Tregs in diffuse large B-cell lymphoma and follicular lymphoma (FL), compared with that in nonmalignant tonsillar tissue. We identified 3 distinct transcriptional states of Tregs: resting, activated, and unconventional LAG3+FOXP3- Tregs. Activated Tregs were enriched in B-NHL tumors, coexpressed several checkpoint receptors, and had stronger immunosuppressive activity compared with resting Tregs. In FL, activated Tregs were found in closer proximity to CD4+ and CD8+ T cells than other cell types. Furthermore, we used a computational approach to develop unique gene signature matrices, which were used to enumerate each Treg subset in cohorts with bulk gene expression data. In 2 independent FL cohorts, activated Tregs was the major subset, and high abundance was associated with adverse outcome. This study demonstrates that Tregs infiltrating B-NHL tumors are transcriptionally and functionally diverse. Highly immunosuppressive activated Tregs were enriched in tumor tissue but absent in the peripheral blood. Our data suggest that a deeper understanding of Treg heterogeneity in B-NHL could open new paths for rational drug design, facilitating selective targeting to improve antitumor immunity.

The Geriatric Prognostic Index: a clinical prediction model for survival of older diffuse large B-cell lymphoma patients treated with standard immunochemotherapy.

The International prognostic Index (IPI) is the most widely used clinical prediction model for diffuse large B-cell lymphoma (DLBCL) patients treated with rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone (R-CHOP), but may be suboptimal in older patients. We aimed to develop and externally validate a clinical prediction model for older, RCHOP- treated DLBCL patients by examining geriatric assessment and lymphoma-related parameters in real-world cohorts. A population-based training set of 365 R-CHOP-treated DLBCL patients ≥70 years was identified through the Cancer Registry of Norway. The external test set consisted of a population-based cohort of 193 patients. Data on candidate predictors were retrieved from the Cancer Registry and through review of clinical records. Cox regression models for 2-year overall survival were used for model selection. Activities of daily living, the Charlson Comorbidity Index, age, sex, albumin, stage, Eastern Cooperative Oncology Group performance status and lactate dehydrogenase level were identified as independent predictors and combined into a Geriatric Prognostic Index (GPI). The GPI demonstrated good discrimination (optimismcorrected C-index 0.752), and identified low-, intermediate- and high-risk groups with significantly different survivals (2- year overall survival, 94%, 65%, and 25%, respectively). At external validation, the continuous and grouped GPI demonstrated good discrimination (C-index 0.727 and 0.710, respectively) and the GPI groups had significantly different survivals (2-year overall survival 95%, 65%, and 44%, respectively). Both the continuous and grouped GPI showed better discrimination than the IPI, revised-IPI and National Comprehensive Cancer Network (NCCN)-IPI (C-index 0.621, 0.583, and 0.670, respectively). In conclusion, we have developed and externally validated a GPI for older DLBCL patients treated with R-CHOP that outperformed the IPI, revised-IPI and NCCN-IPI. A web-based calculator is available at https://wide.shinyapps. io/GPIcalculator/.

A simplified frailty score predicts survival and can aid treatment-intensity decisions in older patients with DLBCL.

Patients with diffuse large B-cell lymphoma (DLBCL) have a median age of 70 years. Yet, empirical knowledge about the treatment of older patients is limited because they are frequently excluded from clinical trials. We aimed to construct a simplified frailty score and examine survival and treatment-related mortality (TRM) according to frailty status and treatment intensity in an older real-world population with DLBCL. All patients aged ≥70 years diagnosed with DLBCL between 2006 and 2016 in southeastern Norway (N = 784) were included retrospectively and divided into training (n = 522) and validation (n = 262) cohorts. We constructed and validated a frailty score based on geriatric assessment variables and examined survival and TRM according to frailty status and treatment. The frailty score identified 3 frailty groups with distinct survival and TRM, independent of established prognostic factors (2-year overall survival [OS]: fit, 82%; unfit, 47%; frail, 14%; P < .001). For fit patients, full-dose R-CHOP (initial dosage >80%) was associated with better survival than attenuated R-CHOP ([R-miniCHOP]; 2-year OS: 86% vs 70%; P = .012), also in adjusted analyses. For unfit and frail patients, full-dose R-CHOP was not superior to R-miniCHOP, whereas an anthracycline-free regimen was associated with poorer survival in adjusted analyses. A simplified frailty score identified unfit and frail patients with a higher risk for death and TRM, which can aid treatment-intensity decisions in older patients with DLBCL. In this study, fit patients benefited from full-dose R-CHOP, whereas unfit and frail patients had no benefit from full-dose R-CHOP over R-miniCHOP. An online calculator for assessment of the frailty score is available at https://wide.shinyapps.io/app-frailty/.