Birgit Federmann

Radioimmunotherapy with yttrium-90-ibritumomab tiuxetan as part of a reduced- intensity conditioning regimen for allogeneic hematopoietic cell transplantation in patients with advanced non-Hodgkin lymphoma: results of a phase 2 study

Forty patients were enrolled in this phase 2 study combining radioimmunotherapy (RIT) using yttrium-90-ibritumomab-tiuxetan (15 MBq [0.4 mCi]/kg) with reduced-intensity conditioning (RIC) using fludarabine (90 mg/m(2)) and 2 Gy total body irradiation followed by allogeneic hematopoietic cell transplantation (HCT) from related (n = 13) or unrelated (n = 27) donors for the treatment of advanced non-Hodgkin lymphoma. Diagnoses were follicular lymphoma (n = 17), chronic lymphocytic leukemia (n = 13), mantle cell lymphoma (n = 8), marginal zone lymphoma (n = 1), and lymphoplasmacytic lymphoma (n = 1). Median age was 55 years (range, 34-68 years). All patients were high risk with refractory disease or relapse after preceding autologous HCT. No additional toxicities attributable to RIT were observed. Engraftment was rapid and sustained. Incidences of acute graft-versus-host disease 2-4 and chronic graft-versus-host disease were 43% and 53%, respectively. Kaplan-Meier-estimated nonrelapse mortality was 45% at 2 years. Twenty-two of 40 patients (55%) are alive, resulting in a Kaplan-Meier-estimated 2-year survival of 51% for all, 67% for follicular lymphoma, 49% for chronic lymphocytic leukemia, and 37% for mantle cell lymphoma patients. The combined use of RIT with RIC is feasible with acceptable toxicity, even in elderly and heavily pretreated patients. This study is registered at www.clinicaltrials.gov as #NCT00302757.

Haploidentical allogeneic hematopoietic cell transplantation in adults using CD3/CD19 depletion and reduced intensity conditioning: a phase II study

Background We report a prospective multicenter phase II study of haploidentical hematopoietic stem cell transplantation using CD3/CD19-depleted grafts after reduced intensity conditioning with fludarabine, thiotepa, melphalan and OKT-3. Design and Methods Sixty-one adults with a median age of 46 years (range 19-65 years) have been enrolled. Diagnoses were acute myeloid leukemia (n=38), acute lymphoblastic leukemia (n=8), non-Hodgkins lymphoma (n=6), myeloma (n=4), chronic myeloid leukemia (n=3), chronic lymphatic leukemia (n=1) and myelodysplastic syndrome (n=1). Patients were considered high risk because of refractory disease (n=18), cytogenetics (n=6), complete remission (≥2) (n=9), chemosensitive relapse in partial remission (n=4) or relapse after prior hematopoietic stem cell transplantation (n=15 allogeneic, n=8 autologous, n=1 both). At haploidentical hematopoietic stem cell transplantation, 30 patients were in complete remission and 31 in partial remission. Grafts contained a median of 7.0×106 (range 3.2-22) CD34+ cells/kg, 4.2×104 (range 0.6-44) CD3+ T cells/kg and 2.7×107 (range 0.00-37.3) CD56+ cells/kg. Results Engraftment was rapid with a median of 12 days to granulocytes more than 0.5×109/L (range 9-50 days) and 11 days to platelets more than 20×109 (range 7-38 days). Incidence of grade IIIV acute graft-versus-host-disease and chronic graft-versus-host-disease was 46% and 18%, respectively. Non-relapse mortality on Day 100 was 23% and 42% at two years. Cumulative incidence of relapse/progression at two years was 31%. Kaplan-Meier estimated 1-year and 2-year overall survival with median follow up of 869 days (range 181-1932) is 41% and 28%, respectively. Conclusions This regimen allows successful haploidentical hematopoietic stem cell transplantation with reduced intensity conditioning in high-risk patients lacking a suitable donor. (clinicaltrials.gov identifier:NCT00202917).

High frequency of MYD88 mutations in vitreoretinal B-cell lymphoma: a valuable tool to improve diagnostic yield of vitreous aspirates

Vitreoretinal diffuse large B-cell lymphoma is a rare disorder, occurring as primary ocular disease or as secondary involvement by primary central nervous system lymphoma. It is usually diagnosed by cytologic, immunocytochemical, and molecular examination of vitreous aspirates. However, distinguishing vitreoretinal diffuse large B-cell lymphoma from uveitis remains difficult, and clonality analysis may be either unsuccessful or misleading. Diffuse large B-cell lymphoma arising in immune-privileged sites (eg, the central nervous system) shows a high frequency of MYD88 mutations. Therefore, we retrospectively assessed the frequency of MYD88 mutations in vitreoretinal lymphoma (VRL) and their diagnostic potential in 75 vitrectomy samples of 69 patients, and validated our results in a separate cohort (n = 21). MYD88 mutations were identified in 20 of 29 (69%) clinically, histologically, and molecularly confirmed VRL, including 6 cases of the test cohort initially diagnosed as reactive (3/6) or suspicious (3/6) for lymphoma. MYD88 mutations, especially L265P, are very frequent in VRL and their detection significantly improves the diagnostic yield of vitrectomy specimens.

MYD88 L265P and CXCR4 mutations in lymphoplasmacytic lymphoma identify cases with high disease activity.

Recurrent mutations in MYD88 have been identified in >90% of lymphoplasmacytic lymphoma (LPL). Recently, WHIM (warts, hypogammaglobulinaemia, infections, myelokathexis) syndrome‐like mutations in CXCR4 have been described in 28% of LPL cases, and seem to impact clinical presentation and response to therapy. We investigated the presence of the MYD88 L265P mutation in 90 decalcified, formalin‐fixed, paraffin‐embedded (FFPE) bone marrow (BM) biopsies, including 51 cases of LPL, 14 cases of B‐cell chronic lymphocytic leukaemia (CLL), 13 cases of marginal zone lymphoma (MZL) and 12 normal controls. In addition, the C‐terminal domain of CXCR4 was sequenced in LPL cases. MYD88 L265P was found in 49/51 (96%) LPL cases and in 1/13 (7·6%) MZL (splenic type), whereas all CLL samples remained negative. The two MYD88 wild type LPL cases were associated with cold agglutinin disease. Mutations in CXCR4 were detected in 17/47 (36·2%) LPL cases, which showed a higher extent of BM infiltration and lower leucocyte counts (P = 0·02), haemoglobin (P = 0·05) and platelet counts (P = 0·01). In conclusion the detection of MYD88 L265P mutation in FFPE samples is reliable and useful for subtyping small B‐cell lymphomas in BM biopsies. In addition, the presence of CXCR4 mutations identifies a subgroup of LPL patients with higher disease activity.

Monocyte-Induced Development of Th17 Cells and the Release of S100 Proteins Are Involved in the Pathogenesis of Graft-versus-Host Disease

Graft-versus-host disease (GvHD) is a major cause of morbidity and mortality after allogeneic hematopoietic cell transplantation. However, the pathophysiology of GvHD remains poorly understood. In this study, we analyzed the induction of Th17 cells by monocytes of patients with GvHD in vitro, demonstrating that monocytes isolated from patients with acute skin and intestinal GvHD stage I–IV and chronic GvHD induce significantly increased levels of Th17 cells compared with patients without GvHD. S100 proteins are known to act as innate amplifier of inflammation. We therefore investigated the presence of S100 proteins in the stool, serum, and bowel tissue of patients with GvHD and the influence of S100 proteins on the induction of Th17 cells. Elevated levels of S100 proteins could be detected in patients with acute GvHD, demonstrating the release of these phagocyte-specific proteins during GvHD. Furthermore, stimulation of monocytes with S100 proteins was found to promote Th17 development, emphasizing the role of S100 proteins in Th17-triggered inflammation. Altogether, our results indicate that induction of Th17 cells by activated monocytes and the stimulatory effects of proinflammatory S100 proteins might play a relevant role in the pathogenesis of acute GvHD. Regarding our data, S100 proteins might be novel markers for the diagnosis and follow-up of GvHD.

Dose-escalated radioimmunotherapy as part of reduced intensity conditioning for allogeneic transplantation in patients with advanced high-grade non-Hodgkin lymphoma.

A total of 20 patients enrolled in a multicenter phase II dose escalation study of radioimmunotherapy (RIT) using yttrium-90-ibritumomab tiuxetan at two dose levels (22 and 30 MBq/kg) in 10 patients, combined with reduced intensity conditioning (RIC) using fludarabine, melphalan and alemtuzumab followed by allogeneic hematopoietic cell transplantation (HCT) from either matched-related (n=5) or matched-unrelated donors (n=15). Postgrafting immunosuppression with cyclosporine was administered. Diagnoses were diffuse large B-cell lymphoma (n=13), transformed CLL (n=4), blastic mantle cell lymphoma (n=2) and follicular lymphoma grade 3 (n=1). Median age was 51 (range, 29–69) years. All patients were high risk with relapsed/refractory disease or relapse after preceding autologous HCT. Median follow-up of patients alive was 1115 (range, 1006–1252) days. No directly RIT-related toxicities were observed. The cumulative incidence of non-relapse mortality was 30%. Incidences of grade II–IV acute and chronic GvHD was 45% and 70%, respectively. Kaplan–Meier estimated 3-year OS and EFS were 20% for both dose levels. In conclusion, dose escalation of RIT and combined use with RIC is feasible with no additional toxicity due to dose escalation. This study is registered on http://clinicaltrials.gov as NCT00302757.

Consensus on the histopathological evaluation of liver biopsies from patients following allogeneic hematopoietic cell transplantation

After allogeneic hematopoietic cell transplantation (alloHCT) liver biopsy is performed for enigmatic liver disorders when noninvasive diagnostic steps have failed in establishing a definitive diagnosis. This document provides an updated consensus on the prerequisites for proper evaluation of liver biopsies in alloHCT patients and the histological diagnostic criteria for liver graft-versus-host disease (GvHD). The Working Group’s recommendations for the histological diagnosis of liver GvHD were derived from the peer-reviewed literature and from the consensus diagnosis of a total of 30 coded liver biopsies. Acceptance of the recommendations was tested by a survey distributed to all HCT centers in Austria, Germany and Switzerland. Consensus was achieved for biopsy indications, methods of sample acquisition and processing, reporting and interpretation of biopsy findings. As GvHD is variably treated and the treatment modalities have changed over time, the panel endorses the use of more frequent biopsies in clinical studies in order to improve the present challenging clinical and diagnostic situation.

Influence of age on outcome after allogeneic hematopoietic cell transplantation: a single center study in patients aged ⩾ 60

Reduced intensity conditioning regimens lead to an increasing use of allogeneic hematopoietic cell transplantation (HCT) in elderly patients. We retrospectively analyzed 151 patients aged ⩾60 receiving allogeneic HCT 2000–2012 at our center. Median age was 66 years. Kaplan–Meier estimated 3-year OS was 42% with a median follow-up of 38 months. Cumulative incidences of progression and non-relapse mortality after 3 years were 38 and 24%. OS was better in the group of patients >65 years with a Kaplan–Meier estimated OS of 50% vs 34%, P=0.060. We observed a significant influence of donor age (<50 years: 53% vs >50 years: 30%, P=0.017) and gender match (matched: 57% vs mismatched: 32%, P=0.007) on outcome. The use of a matched related donor was inferior compared with a matched or mismatched unrelated donor (19% vs 47%, P=0.015). On multivariate analysis there was an increased hazard ratio for a non-gender-matched HLA-matched-related donor (hazard ratio 3.23, 95% confidence interval 1.55–6.74, P=0.002). Age had no significant impact on OS (P=0.414). In conclusion, the data suggest that older age alone has no negative impact on the outcome of allogeneic HCT. Transplant decision should be tailored to disease risk and patient performance status rather than age.

The detection of SRSF2 mutations in routinely processed bone marrow biopsies is useful in the diagnosis of chronic myelomonocytic leukemia

Diagnosis of chronic myelomonocytic leukemia (CMML) is based on a combination of clinical, laboratory, and morphological parameters, including persistent peripheral blood monocytosis. Recently, mutations of serine/arginine-rich splicing factor 2 (SRSF2) have been identified in 40% to 50% of CMMLs and occasionally in other myeloid disorders. In this study, we established a robust assay for the detection of SRSF2 mutations in decalcified, paraffin-embedded bone marrow (BM) biopsies and investigated its diagnostic utility. BM biopsies of 78 patients with myeloid neoplasms, including 36 CMMLs, 22 myelodysplastic syndromes (MDS), and 20 Ph- myeloproliferative neoplasms (MPN) were analyzed. The region around hot spot P95 in exon 1 of SRSF2 was amplified and bidirectionally sequenced. In addition, a restriction fragment length polymorphism analysis was established. The JAK2 V617F mutation was investigated by allele-specific polymerase chain reaction. SRSF2 mutations were identified in 16 (44%) of 36 CMMLs, including 1 of 3 cases with associated systemic mastocytosis, 4 (20%) of 20 Ph- MPN, and 1 (4.5%) of 22 MDS. Restriction fragment length polymorphism analysis detected all mutations with the exception of a single P95A. Of note, 2 cases of JAK2 V617F+ primary myelofibrosis with SRSF2 mutation initially were diagnosed as CMML based on significant peripheral blood monocytosis. In CMML, no correlation with histopathology and/or clinical parameters was observed, but SRSF2 mutations were associated with normal karyotype (P < .001). In summary, SRSF2 mutations are frequent in CMML and a useful diagnostic feature demonstrable in BM biopsies, allowing a definitive diagnosis for cases with minimal dysplasia and normal karyotype. The role of SRSF2 mutations in cases with hybrid features between primary myelofibrosis and CMML needs further investigation.

The Immune Checkpoint Modulator OX40 and Its Ligand OX40L in NK-Cell Immunosurveillance and Acute Myeloid Leukemia

The TNFR-family member OX40 is expressed on AML cells, influencing various AML cellular functions as well as immunosurveillance by OX40L-expressing NK cells. These effects should be considered when developing OX40-targeted approaches for cancer immunotherapy. The TNF receptor family member OX40 promotes activation and proliferation of T cells, which fuels efforts to modulate this immune checkpoint to reinforce antitumor immunity. Besides T cells, NK cells are a second cytotoxic lymphocyte subset that contributes to antitumor immunity, particularly in leukemia. Accordingly, these cells are being clinically evaluated for cancer treatment through multiple approaches, such as adoptive transfer of ex vivo expanded polyclonal NK cells (pNKC). Here, we analyzed whether and how OX40 and its ligand (OX40L) influence NK-cell function and antileukemia reactivity. We report that OX40 is expressed on leukemic blasts in a substantial percentage of patients with acute myeloid leukemia (AML) and that OX40 can, after stimulation with agonistic OX40 antibodies, mediate proliferation and release of cytokines that act as growth and survival factors for the leukemic cells. We also demonstrate that pNKC differentially express OX40L, depending on the protocol used for their generation. OX40L signaling promoted NK-cell activation, cytokine production, and cytotoxicity, and disruption of OX40–OX40L interaction impaired pNKC reactivity against primary AML cells. Together, our data implicate OX40/OX40L in disease pathophysiology of AML and in NK-cell immunosurveillance. Our findings indicate that effects of the OX40–OX40L receptor–ligand system in other immune cell subsets and also malignant cells should be taken into account when developing OX40-targeted approaches for cancer immunotherapy. Cancer Immunol Res; 6(2); 209–21. ©2018 AACR.