Hematopoietic stem cell mobilization with the reversible CXCR4 receptor inhibitor plerixafor (AMD3100)—Polish compassionate use experience

Recent developments in the field of targeted therapy have led to the discovery of a new drug, plerixafor, that is a specific inhibitor of the CXCR4 receptor. Plerixafor acts in concert with granulocyte colony-stimulating factor (G-CSF) to increase the number of stem cells circulating in the peripheral blood (PB). Therefore, it has been applied in the field of hematopoietic stem cell mobilization. We analyzed retrospectively data regarding stem cell mobilization with plerixafor in a cohort of 61 patients suffering from multiple myeloma (N = 23), non-Hodgkin’s lymphoma (N = 20), or Hodgkin’s lymphoma (N = 18). At least one previous mobilization attempt had failed in 83.6% of these patients, whereas 16.4% were predicted to be poor mobilizers. The median number of CD34+ cells in the PB after the first administration of plerixafor was 22/μL (range of 0–121). In total, 85.2% of the patients proceeded to cell collection, and a median of two (range of 0–4) aphereses were performed. A minimum of 2.0 × 106 CD34+ cells per kilogram of the patient’s body weight (cells/kg b.w.) was collected from 65.6% of patients, and the median number of cells collected was 2.67 × 106 CD34+ cells/kg b.w. (0–8.0). Of the patients, 55.7% had already undergone autologous stem cell transplantation, and the median time to neutrophil and platelet reconstitution was 12 and 14 days, respectively. Cases of late graft failure were not observed. We identified the diagnosis of non-Hodgkin’s lymphoma and previous radiotherapy as independent factors that contributed to failure of mobilization. The current report demonstrates the satisfactory efficacy of plerixafor plus G-CSF for stem cell mobilization in heavily pre-treated poor or predicted poor mobilizers

Clinicopathological characteristics and outcome of plasmablastic lymphoma patients: A single-center retrospective analysis.

e20034 Background: Plasmablastic lymphoma (PBL) is a rare CD20-negative lymphoma with an aggressive clinical course and short median survival ranging from 9 to 32 months. It is often associated with HIV infection but it also affects immunocompetent patients. Due to the rare occurrence most data comes from small, retrospective series. Methods: This is a retrospective single-center analysis of PBL patients (pts) referred to MSCNRIO between 2003-2019. Diagnosis was established according to the WHO 2017 classification criteria. Kaplan–Meier method was used for calculating overall survival (OS) and progression-free-survival (PFS) and the log-rank test for comparisons. Univariate analysis of prognostic factors was carried out. Results: 24 pts with a diagnosis of PBL were included. The median age at diagnosis was 54 years (range 29-90). 15 pts (63%) were men. LDH was elevated in 10 pts (41%). Stage III or IV was reported in 21 (87.5%) pts, IPI score of 3-5 in 12 (50%) and ECOG performance status &gt; 1 in 7 pts (29%). 20 pts (83.3%) had extranodal involvement, including oropharynx (n = 12), gastrointestinal tract (n = 1), bone marrow (n = 7), skeletal bone (n = 9), central nervous system (n = 3), skin and subcutaneous tissue (n = 2). Only 3 pts (13%) were infected by HIV, 2 had history of immunosuppressive therapy. Pathologically, all cases were negative for CD20 and positive for CD38 or CD138 expression. Ki67 &gt; 90% was noted in 16 cases (66%). 11 pts received CHOP chemotherapy, 3 pts - thalidomide- and 4 pts - bortezomib-based regimens, 1 was treated with both agents. 4 pts received different protocols; 1 pt received no treatment. CR was observed in 8 pts (33%), PR in 6 (25%) and no response in 10 (42%). 2 pts received ASCT in the 1st remission. 17 pts (71%) experienced relapsed/progressive disease. 16 pts died: 11 from disease progression, 2 from other neoplasm. With a median follow-up of 20 months (range 2-122) median OS was 21 months and 2-year OS rate was 46% (95%C.I 27%, 65%). 2-year PFS rate was 37% (95% C.I. 17%, 57%), with median PFS 12 months (range 0.7-105). On univariate analysis there was a trend for correlation of high IPI with PFS; (95%C.I 0.99-1.03, P= 0.08). Achieving CR significantly correlated with better OS (HR 5; 95% C.I. 1.41-17; P= 0.01)) and PFS (HR 5.1, 95%C.I. 1.4, 18; P= 0.004). Conclusions: Our results confirm other reported data on PBL. Patients in our cohort shared typical clinical features but majority of them were immunocompetent. PBL prognosis remains poor despite incorporating novel agents into treatment and requires new therapeutic approaches. </jats:p

Omission of Radiotherapy in Primary Mediastinal B-Cell Lymphoma: IELSG37 Trial Results

PURPOSE The role of consolidation radiotherapy in patients with primary mediastinal B-cell lymphoma (PMBCL) is controversial. METHODS The IELSG37 trial, a randomized noninferiority study, aimed to assess whether irradiation can be omitted in patients with PMBCL with complete metabolic response (CMR) after induction immunochemotherapy. The primary end point was progression-free survival (PFS) at 30 months after random assignment. Patients with CMR were randomly assigned to observation or consolidation radiotherapy (30 Gy). With a noninferiority margin of 10% (assuming a 30-month PFS of 85% in both arms), a sample size of 540 patients was planned with 376 expected to be randomly assigned. RESULTS The observed events were considerably lower than expected; therefore, primary end point analysis was conducted when ≥95% of patients were followed for ≥30 months. Of the 545 patients enrolled, 268 were in CMR after induction and were randomly assigned to observation (n 5 132) or radiotherapy (n 5 136). The 30-month PFS was 96.2% in the observation arm and 98.5% in the radiotherapy arm, with a stratified hazard ratio of 1.47 (95% CI, 0.34 to 6.28) and absolute risk difference of 0.68% (95% CI, -0.97 to 7.46). The 5-year overall survival (OS) was 99% in both arms. Nonrandomized patients were managed according to local policies. Radiotherapy was the only treatment in 86% of those with Deauville score (DS) 4 and in 57% of those with DS 5. The 5-year PFS and OS of patients with DS 4 (95.8% and 97.5%, respectively) were not significantly different from those of randomly assigned patients. Patients with DS5 had significantly poorer 5-year PFS and OS (60.3% and 74.6%, respectively). CONCLUSION This study, the largest randomized trial of radiotherapy in PMBCL, demonstrated favorable outcomes in patients achieving CMR with no survival impairment for those omitting irradiation