Prognostic information from nonmalignant and malignant lymphocytes in follicular lymphoma in relation to therapy

Follicular lymphoma is the most common indolent lymphoma. It is composed of centrocytes and centroblasts, residing in follicles that also harbour nonmalignant immune and stroma cells. Follicular lymphoma is graded according to the World Health Organization criteria that are based on the frequency of centroblasts. There is consensus that grades 1 and 2 are indolent, but not whether grade 3 is aggressive. Differences between grades 3A and 3B are also unclear. The nonmalignant cells in the microenvironment interact with the tumour cells and with each other. These interactions may be important for disease outcome. Since the introduction of the therapeutic monoclonal anti-CD20 antibody rituximab, the prognosis of follicular lymphoma has improved. It is likely that the mechanisms of rituximab affect and involve not only CD20+ follicular lymphoma cells but also the surrounding as well as the systemic immune cells. The aim of this thesis was to identify biological predictors for outcome in follicular lymphoma in relation to therapy. In paper I, using flow cytometry, we reported that higher numbers of CD8+ T cells in diagnostic lymph nodes are an independent predictor of better overall and disease-specific survival. This finding was reproduced in paper II in which computerised quantifications of tissue microarrays were used for a unifying multivariate model. This model showed that many cells in the microenvironment were independently important for outcome. Higher levels of cells positive for CD8 (cytotoxic T cells), forkhead box protein 3 (regulatory T cells) and programmed death-1 (PD-1+ T cells) correlated with good prognosis, but higher levels of cells positive for CD4 (helper T cells) and CD68 (macrophages) with poor. The best predictors for poor outcome were increasing CD4/CD8 and follicular/interfollicular CD4 ratios, suggesting that outcome is influenced by the balance between detrimental follicular B-helper and helper2 T-cells on one hand and favourable cytotoxic and helper1 T cells on the other. In paper III we used prospectively recorded flow cytometry analyses from two randomised trials where all patients received single rituximab with or without interferon-α priming. T cells in tumours (both CD4+ and CD8+) were associated with fast and good clinical responses to rituximab, while T cells in blood (both CD4+ and CD8+) correlated with slower but good and sustained responses, and were more important for survival. Interferon-α abrogated the dependence on high numbers of CD8+ cells (in both blood and tumours) for good rituximab responses. In paper IV we reviewed the follicular lymphoma grades in 828 patients with long follow-up times, of whom 40% received upfront rituximab. Compared with grade 1–3A patients and independently of clinical factors, grade 3B patients showed higher mortality but outcome was improved after upfront anthracyclines. Grade 3B patients experienced no relapses or deaths beyond five years of follow-up. Furthermore, patients with grade 3B were different in their clinical characteristics. In the entire population, patients with grade 3A had similar outcome as those with grade 1–2. However, in patients given upfront rituximab-containing therapy, increasing grades of 1, 2, and 3A correlated with better overall survival and time to treatment-failure, independently of clinical factors. We conclude that outcome in follicular lymphoma is determined by the balance between competing immune cells in the microenvironment and by their interactions with each other and with the tumour cells. Rituximab and interferon-α alter the prognostic properties of the immune cells, and also involve systemic T cells that may be very important for disease outcome. Grade 3B, or follicular large B-cell lymphoma, is a distinct, aggressive but curable entity. Grades 1, 2 and 3A are indolent and incurable. Increasing grades predict better outcome with rituximab therapy. Our findings suggest a future of personalised therapy based on biological characteristics of the patients and of the tumours

Systemic and Intra-Nodal Activation of NK Cells After Rituximab Monotherapy for Follicular Lymphoma

Monotherapy with the anti-CD20 monoclonal antibody rituximab can induce complete responses (CR) in patients with follicular lymphoma (FL). Resting FcRγIII+ (CD16+) natural killer (NK) cells respond strongly to rituximab-coated target cells in vitro. Yet, the contribution of NK cells in the therapeutic effect in vivo remains unknown. Here, we followed the NK cell repertoire dynamics in the lymph node and systemically during rituximab monotherapy in patients with FL. At baseline, NK cells in the tumor lymph node had a naïve phenotype albeit they were more differentiated than NK cells derived from control tonsils as determined by the frequency of CD56dim NK cells and the expression of killer cell immunoglobulin-like receptors (KIR), CD57 and CD16. Rituximab therapy induced a rapid drop in NK cell numbers coinciding with a relative increase in the frequency of Ki67+ NK cells both in the lymph node and peripheral blood. The Ki67+ NK cells had slightly increased expression of CD16, CD57 and higher levels of granzyme A and perforin. The in vivo activation of NK cells was paralleled by a temporary loss of in vitro functionality, primarily manifested as decreased IFNγ production in response to rituximab-coated targets. However, patients with pre-existing NKG2C+ adaptive NK cell subsets showed less Ki67 upregulation and were refractory to the loss of functionality. These data reveal variable imprints of rituximab monotherapy on the NK cell repertoire, which may depend on pre-existing repertoire diversity

Excellent survival after R‐Hyper‐CVAD in hospitalized patients with high‐risk large B‐cell lymphoma: The Karolinska experience

Abstract Patients with high‐risk aggressive B‐cell lymphoma exhibit poor survival after R‐CHOP. More intensive regimens yield higher rates of remission but also of complication. We investigated all 401 patients < 70 years with high‐risk (age‐adjusted [aa] international prognostic index [IPI] ≥2, extranodal, or bulky) aggressive B‐cell lymphoma hospitalized at Karolinska for urgent start of immunochemotherapy (129 R‐Hyper‐CVAD; 261 R‐CHOP/R‐CHOEP). Patients showed IPI 3–5 (70%), WHO PS ≥2 (49%), bulky disease (70%), extranodal (75%) and CNS (8%) involvement. Five‐year overall/progression‐free survival (OS/PFS) was better in patients who started R‐Hyper‐CVAD (84%/77%) compared with R‐CHOP/R‐CHOEP (66%/55%). Differences were independent in multivariable analysis, seen in all patient categories, and accentuated in extreme high‐risk disease: R‐Hyper‐CVAD vs. R‐CHOP/R‐CHOEP showed 5‐year PFS 69% vs.40% in aaIPI 3 and 88% vs. 38% in CNS involvement. For validation, survival was compared between the two Karolinska sites and calendar periods. Survival was superior 2006–2010 at the site that introduced R‐Hyper‐CVAD/R‐MA 2006, identical at both sites 2011–2017 after the other site adopted R‐Hyper‐CVAD/R‐MA 2011, and excellent 2018–2020 when R‐Hyper‐CVAD/R‐MA use increased to 75% of patients. Despite considerable toxicity, also patients aged 61–69 years showed better survival with R‐Hyper‐CVAD/R‐MA. This is the largest single‐centre series of patients treated with R‐Hyper‐CVAD/R‐MA, showing favourable outcome in high‐risk aggressive B‐cell lymphoma

High incidence of chronic graft-versus-host disease after myeloablative allogeneic stem cell transplantation for chronic lymphocytic leukemia in Sweden : graft-versus-leukemia effect protects against relapse

Allogeneic hematopoietic stem cell transplantation (allo-SCT) is a potentially curative treatment option for eligible patients with chronic lymphocytic leukemia (CLL). However, it is known that cure of CLL is only possible if a graft-versus-leukemia effect is present. Between 1994 and 2007, 48 adults underwent allo-SCT for poor-risk CLL in Sweden. Of these, ten (21%) patients aged 24-53 years (median: 46 years) received myeloablative conditioning (MAC), based on TBI and cyclophosphamide. All MAC patients had refractory, poorly controlled CLL before allo-SCT (partial remission in 9/10 patients and progressive disease in one). The cumulative incidence of acute graft-versus-host disease (GVHD) grades II-IV was 30%. Nine patients developed chronic GVHD; extensive in four. Rates of nonrelapse mortality at 1, 3 and 10 years were 0, 10 and 20%, respectively. Two patients relapsed 36 and 53 months after transplantation. Six patients were still alive after a median follow-up time of 11.5 years (range 5.9-13.7). The probabilities of relapse-free and overall survival from 1, 3 and 5 years after transplantation were 100, 90 and 70%, and 100, 90 and 80%, respectively. Nevertheless, our analysis of long-term outcome after MAC allo-SCT for CLL suggests that younger patients with poorly controlled CLL may benefit from MAC allo-SCT

Splenic marginal zone lymphoma in Sweden 2000–2020: Increasing rituximab use and better survival in the elderly

Abstract The treatment of splenic marginal zone lymphoma is debated: splenectomy (the old standard‐of‐care) is better than chemotherapy but maybe not better than rituximab‐containing treatment. We examined all 358 patients diagnosed with splenic marginal zone lymphoma in Sweden 2000–2020. The median overall survival was 11.0 years. The median age was 73 years; 61% were women. Age was the only independently prognostic clinical characteristic. Eighty‐six patients were started on wait‐and‐watch, 90 rituximab monotherapy, 47 rituximab‐chemotherapy, 88 splenectomy, 37 chemotherapy, and 10 both systemic therapy and splenectomy. Overall survival was inferior in patients treated with chemotherapy, but equal in patients treated with rituximab, rituximab‐chemotherapy and splenectomy. Patients treated with both systemic therapy and splenectomy showed good outcome, suggesting that surgery can be safely reserved for nonresponders. After adjustment for age, survival did not differ between patients started on wait‐and‐watch and those treated with splenectomy or rituximab‐containing therapy. Over time, rituximab use and survival increased in patients ≥73 years. This is, to our knowledge, the largest population‐based study of splenic marginal zone lymphoma patients treated with upfront rituximab. We conclude that wait‐and‐watch remains the most reasonable option in asymptomatic splenic marginal zone lymphoma patients. Symptomatic patients should be offered single‐agent rituximab in first line

Real‐world data on treatment concepts in classical Hodgkin lymphoma in Sweden 2000–2014, focusing on patients aged >60 years

Abstract Treatment for patients > 60 years with classical Hodgkin lymphoma (cHL) is problematic; there is no gold standard, and outcome is poor. Using the Swedish Lymphoma Registry, we analysed all Swedish patients diagnosed with cHL between 2000 and 2014 (N = 2345; median age 42 years; 691 patients were >60 years). The median follow‐up time was 6.7 years. Treatment for elderly patients consisted mainly of ABVD or CHOP, and the younger patients were treated with ABVD or BEACOPP (with no survival difference). In multivariable analysis of patients > 60 years, ABVD correlated with better survival than CHOP (p = 0.027), and ABVD became more common over time among patients aged 61–70 years (p = 0.0206). Coinciding with the implementation of FDG‐PET/CT, the fraction of advanced‐stage disease increased in later calendar periods, also in the older patient group. Survival has improved in cHL patients > 60 years (p = 0.027), for whom ABVD seems superior to CHOP