A multi-center analysis of the impact of DA-EPOCH-R dose-adjustment on clinical outcomes of patients with double/triple-hit lymphoma

Patients with double- and triple-hit lymphomas (DHL/THL) have inferior outcomes with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP), and higher-intensity regimens such as dose-adjusted (DA)-EPOCH-R are standard. Dose-intensification of DA-EPOCH-R is guided by hematologic toxicity, without conclusive benefit for DHL/THL patients. To determine if cumulative doses of DA-EPOCH-R or compliance with dose adjustment impacts survival, we retrospectively evaluated detailed clinical data from 109 adult (age ≥18 years) patients with DHL/THL treated with ≥4 cycles of induction DA-EPOCH-R from 2014 to 2019 at six centers. A comprehensive multivariate analysis was performed. Survival outcomes for the entire cohort were comparable to historical estimates for DHL/THL treated with this regimen (median follow-up 27.9 months). Overall survival (OS) and progression-free survival (PFS) were not significantly associated with cumulative chemotherapy dose, dose escalation, or compliance with dose adjustment. Heterogeneous dosing practices were observed. Prospective investigation is warranted to evaluate the practice of dose adjustment of R-EPOCH for patients with DHL/THL.

Outcomes of Burkitt lymphoma (BL) managed in academic (Acad) or community (Comm) centers: real-world evidence (RWE) from 30 US sites

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Background: Prior analyses have suggested better overall survival (OS) of cancer patients (pts) treated in Acad rather than Comm hospitals, but these disparities may reflect different patient characteristics. We examined outcomes of pts with BL in a large RWE cohort from 30 US healthcare systems (Evens, ASH 2019) with a mix of Acad and affiliated Comm sites. Methods: We collected clinical data on adults with BL diagnosed in 2009-2018, individually assigned to Acad or Comm principal setting of care. We compared duration of chemotherapy (CTx, incl. standard CODOX-M/IVAC, hCVAD/MA, DA-EPOCH), rates of complete response (CR), progression-free survival (PFS), and OS adjusting for age, sex, HIV, performance status (PS), stage, LDH > 3x upper limit of normal (ULN), involvement of bone marrow or cerebrospinal fluid (CSF), reporting adjusted risk (RR) or hazard ratio (HR) with 95% CI. Results: Among 641 BL pts, 77 (12%) were managed in Comm setting. Comm pts had lower median age (45 vs 48 in Acad, P= .049), less frequent HIV (13% vs 23%, P= .039), less marrow (21% vs 36%, P= .009) or detected CSF involvement (8% vs 15%, P= .11), and less LDH > 3xULN (21% vs 41%, P= .013), with no significant differences in sex, PS, stage, hemoglobin, or receipt of CTx (97% vs 99%). Acad sites more often applied standard intensive CTx regimens (93% vs 85%, P= .03) and rituximab (92% vs 79%, P= .001), without significant difference in median time to CTx ( P= .69) or treatment-related mortality (TRM, P= .16). Pts managed in Comm (vs Acad) sites were less likely to achieve CR (61% vs 75%, P= .03; RR = 0.79 [0.65-0.95]) and had worse 3-year PFS (46% vs 67%, log-rank P= .003; HR = 2.17 [1.51-3.14]) and OS (53% vs 72%, P= .006; HR = 2.20 [1.48-3.25]). There was no significant interaction with age, sex, HIV, PS, or CSF involvement. Excess mortality concentrated in the 1st year of follow-up. CR, PFS, and OS appeared similar between Acad and Comm settings for pts receiving hCVAD or DA-EPOCH, but outcomes were significantly worse in Comm setting for pts receiving CODOX-M/IVAC. Median number of cycles did not differ between Comm or Acad sites, but median duration of CODOX-M/IVAC delivery was significantly longer in Comm setting (113 vs 101 days, P= .023). Conclusions: In this large RWE analysis, superior outcomes of adults with BL in Acad setting were not explained by baseline patient characteristics or TRM. Differences in the use of standard CTx regimens, rituximab, duration of Ctx, and CR rates suggest need for further research on potential barriers to delivery of intensive CTx for BL in a broader Comm setting.

Post-transplant lymphoproliferative disorder (PTLD) after solid organ transplant (SOT): A multicenter real world analysis (RWA) of 877 patients (pts) treated in the modern era

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Background: Historically, SOT PTLD have modest outcomes in part due to heterogeneous treatment approaches. Additionally, there remains an absence of a large data repository in PTLD to help delineate contemporary pt outcomes & prognostic factors. We conducted a large, multicenter RWA to study outcomes & prognostication of SOT PTLD in the modern era. Methods: Retrospective data on 877 untreated SOT PTLD pts ages ≥18 years (yrs) (2000-2018) were analyzed from 15 academic centers. Prognostic factors for relapse free survival (RFS) & overall survival (OS) were assessed by Cox model. Results: The median age at diagnosis was 54 yrs (range 18-84). The majority of pts were white (78%) & male (67%). Median time from SOT to PTLD diagnosis was 57 months (range 0.23-470). SOT types: kidney (41%) liver (19%), lung (16%), and heart (11%); 11% multi-organ. Tumor was EBV+ in 52%. Graft involvement (18%) and rejection (21%) were seen in a proportion of pts. Most pts had reduction in immunosuppression (79%) and rituximab (R)-containing regimen (61%) as part of 1st line therapy (Tx). Most common Tx: R monotherapy (34%), R+chemotherapy (29%) & chemotherapy without R (8%). Maintenance R use was infrequent (6%). Overall response rate was 63% [51% complete response (CR) and 12% partial response (PR)] and 19% of pts had primary refractory disease. With 44-month median follow-up (0.1-304), 62% of pts were alive. Median OS & RFS for all pts were 12 & 9 yrs, respectively, while differential survival rates were identified for several pt subsets (Table). On univariate analysis, lung SOT was associated with borderline RFS (HR 0.68 [95% CI 0.44-1.03], P= 0.07) and inferior OS (HR 0.67 [95% CI 0.49-0.91], P= 0.012), while EBV negative PTLD was associated with poorer RFS (HR 1.51 [95% CI 1.12-2.04, P= 0.006). In addition, achievement of PR to 1st line Tx vs CR was strongly prognostic for inferior RFS (HR 2.58 [95% CI 1.88-3.54], P< .0001) and OS (HR 2.30 [95% CI 1.60-3.29], P< .0001). Conclusions: In this large, multicenter PTLD RWA, type of SOT was strongly associated with long-term RFS and OS and EBV status predicted RFS. Furthermore, depth of response to 1st line Tx was a critical determinant for long-term pt survival. [Table: see text]

Prostacyclin production in tryptase and thrombin stimulated human bladder endothelial cells: effect of pretreatment with phospholipase A2 and cyclooxygenase inhibitors

PURPOSE

Thrombin and tryptase stimulation of human bladder microvascular endothelial cells (Cambrex Bioscience, Walkersville, Maryland) results in the production of multiple membrane phospholipid derived inflammatory mediators via the activation of a calcium independent phospholipase A2 that may have important implications in bladder inflammatory conditions, such as interstitial cystitis. We examined the effect of multiple phospholipase A2 and cyclooxygenase inhibitors on the immediate release of prostacyclin from human bladder microvascular endothelial cells.

MATERIALS AND METHODS

We stimulated confluent human bladder microvascular endothelial cell monolayers with thrombin or tryptase and measured the immediate release of prostacyclin. Human bladder microvascular endothelial cells were pretreated with several selective phospholipase A2 and cyclooxygenase inhibitors before thrombin or tryptase stimulation to determine which combination of phospholipase A2/cyclooxygenase isoforms was involved in this process. Phospholipase A2 activity was measured using (16:0, [3H]18:1) plasmenylcholine substrate in the absence of calcium. [3H] arachidonic acid release was measured in the surrounding medium from prelabeled human bladder microvascular endothelial cell monolayers. Prostacyclin release into the surrounding medium was measured using a commercially available immunoassay kit.

RESULTS

The immediate increase in prostacyclin release from thrombin or tryptase stimulated human bladder microvascular endothelial cells depended on the activation of membrane associated calcium independent phospholipase A2, resulting in an increase in arachidonic acid production. Constitutively active cyclooxygenase-1 was then responsible for further metabolism of free arachidonic acid to prostacyclin.

CONCLUSIONS

These results show that the search for a suitable anti-inflammatory agent that selectively target specific phospholipase A2 isoforms requires rigorous testing in several cell types in response to various stimuli.

Protease-activated receptor stimulation activates a Ca2+-independent phospholipase A2 in bladder microvascular endothelial cells

Increased mast cell numbers and mast cell activation represent one of the prevalent etiologic theories for interstitial cystitis, an inflammatory condition in the bladder. This study was designed primarily to determine whether increased mast cell tryptase in the bladder wall may play a role in activating bladder endothelial cell phospholipase A(2) (PLA(2)), leading to increased inflammatory phospholipid metabolite accumulation, which may propagate the inflammatory process. We stimulated human bladder microvascular endothelial cells with thrombin or tryptase and measured the activation of PLA(2) and the production of multiple membrane phospholipid-derived inflammatory mediators. Thrombin and tryptase stimulation resulted in activation of a Ca(2+)-independent PLA(2), leading to increased release of arachidonic acid and prostacyclin and increased production of platelet-activating factor. These responses were blocked completely by pretreatment of human bladder microvascular endothelial cells with the Ca(2+)-independent PLA(2)-selective inhibitor bromoenol lactone. The combination of increased prostacyclin and platelet-activating factor in the bladder circulation may result in vasodilation and increased polymorphonuclear leukocyte adherence to the endothelium and may facilitate recruitment of polymorphonuclear leukocytes to the bladder wall of patients with interstitial cystitis.

Measurement of the motility of endothelial cells in confluent monolayers

OBJECTIVE

The reported experiments were designed to develop and test a method to measure the motility of endothelial cells in confluent cultures.

METHODS

Endothelial cell cultures were recorded by time-lapse video. Frames from the recording were digitized, and cell locations were identified at 30-minute intervals using either the centroids or nuclei. The speed of the cells was determined for distances between their successive positions. Cells were stained immunocytochemically to determine the status of their adherens junctions.

RESULTS

Prior to reaching confluence cells exhibited motility unhampered by collisions. After reaching confluence, cells continued to exhibit motility that decreased with time until the cells ceased effective movement. The motility in confluent monolayers persisted in the presence of complete adherens junctions. Motility could be restored in quiescent confluent cultures by the addition of fibroblast growth factor 2 (FGF-2). Generally, cells responding to FGF-2 moved without obvious loss of adherens junctions.

CONCLUSION

These experiments provide evidence that (1) endothelial cells in culture are motile, (2) they do not form circumferential adherens junctions until the culture reaches confluency, (3) the establishment of adherens junctions itself does not interdict cell motion, and (4) the immotile state is reversible by FGF-2 in the presence of adherens junctions.