Characterization of relapse patterns in patients with acute lymphoblastic leukemia treated with blinatumomab

2020 ◽  
pp. 107815522093485
Author(s):  
Kimberly M Lau ◽  
Ila M Saunders ◽  
Aaron M Goodman

Introduction Blinatumomab is a CD19/CD3 bispecific T-cell engager (BiTE) antibody that simultaneously binds CD19 on the surface of B-cells and CD3 on the surface of T-cells, resulting in tumor cell lysis. It is approved for the treatment of patients with relapsed/refractory B-cell acute lymphoblastic leukemia (B-ALL) and in patients with minimal residual disease after intensive induction chemotherapy. Relapse patterns after treatment with blinatumomab have not been well characterized. Methods We reviewed patients treated with blinatumomab with relapsed, refractory or minimal residual disease-positive B-ALL from 1 December 2014 to 31 December 2018 at a single academic medical center. Patient demographics, blast percentage prior to blinatumomab initiation, prior lines of therapy, blinatumomab treatment duration, sites of relapse, progression free survival, and overall survival were collected. Results A total of 20 patients were identified. Four (20%) patients developed extramedullary relapse following blinatumomab. The median time from treatment initiation to extramedullary relapse was 179 days (range 47–241). Sites of extramedullary relapse included the pancreas, adrenal gland, kidneys, liver, parotid gland, and brain. Conclusion Extramedullary relapse occurs frequently following treatment of B-ALL with blinatumomab. Further studies aimed at preventing extramedullary relapse following blinatumomab treatment are warranted.

2017 ◽  
Vol 35 (15_suppl) ◽  
pp. e18517-e18517
Author(s):  
Alissa Minkovsky ◽  
Karry Charest ◽  
Ryan Schmidt ◽  
Debra Briggs ◽  
Daniel J. DeAngelo ◽  
...  

e18517 Background: Multiparametric flow cytometry (FC) of bone marrow aspirate (BM) is a widely used method of minimal residual disease (MRD) assessment in acute lymphoblastic leukemia (ALL). In practice, ALL with hematogone-like phenotype and patients with recurrence of isolated extramedullary disease present challenges in accurate determination of MRD status. We hypothesized that addition of FC MRD of peripheral blood would aid in the interpretation of MRD status. Methods: 76 matched BM and PB specimens were analyzed independently for presence of ALL MRD by 6-color FC. Results: The overall rate of BM MRD-positivity was 24% (18/76) and PB was also MRD-positive in 22% (4/18) of BM-positive cases. PB MRD sensitivity and specificity relative to BM MRD was 13% [95% confident interval (CI) 2%-42%] and 98% [88-100%] for B-ALL samples (n = 65) and 67% [13%-98%] and 75% [36%-95%] for T-ALL samples (n = 11), respectively. We identified 2 cases with evidence of leukemic cells in PB at the time of the extramedullary relapse that were interpreted as MRD-negative in BM. Conclusions: PB MRD demonstrates high specificity with relatively low sensitivity, especially in B-ALL when compared to T-ALL. The use of combined PB and BM samples in MRD assessment by current FC methods may have added clinical and diagnostic value in patients with high risk of extramedullary relapse, including PB MRD as a non-invasive method for monitoring of systemic relapse.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Stephanie L. Rellick ◽  
Gangqing Hu ◽  
Debra Piktel ◽  
Karen H. Martin ◽  
Werner J. Geldenhuys ◽  
...  

AbstractB-cell acute lymphoblastic leukemia (ALL) is characterized by accumulation of immature hematopoietic cells in the bone marrow, a well-established sanctuary site for leukemic cell survival during treatment. While standard of care treatment results in remission in most patients, a small population of patients will relapse, due to the presence of minimal residual disease (MRD) consisting of dormant, chemotherapy-resistant tumor cells. To interrogate this clinically relevant population of treatment refractory cells, we developed an in vitro cell model in which human ALL cells are grown in co-culture with human derived bone marrow stromal cells or osteoblasts. Within this co-culture, tumor cells are found in suspension, lightly attached to the top of the adherent cells, or buried under the adherent cells in a population that is phase dim (PD) by light microscopy. PD cells are dormant and chemotherapy-resistant, consistent with the population of cells that underlies MRD. In the current study, we characterized the transcriptional signature of PD cells by RNA-Seq, and these data were compared to a published expression data set derived from human MRD B-cell ALL patients. Our comparative analyses revealed that the PD cell population is markedly similar to the MRD expression patterns from the primary cells isolated from patients. We further identified genes and key signaling pathways that are common between the PD tumor cells from co-culture and patient derived MRD cells as potential therapeutic targets for future studies.


Sign in / Sign up

Export Citation Format

Share Document