Risk score and prognostication modeling based on mRNA expressivity in the tumor microenvironment of hepatocellular carcinoma

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Background: Stromal elements in the tumor microenvironment (TME) impact prognosis and response to therapy. Advances in mRNA-sequencing improved understanding of gene expressivity, but few models exist to model prognosis in association with mRNA expression. Methods: Clinical data and mRNA-seq of 256 patients (pts) with hepatocellular carcinoma (HCC) were obtained from TCGA. The expressivity of 191 genes enriched in cellular and structural components of the TME and clinical data were analyzed using machine learning, multivariable COX model, and Kaplan-Meier (KM) analysis to model risk score (RS) for prediction of prognosis. Results: Prognostication was modeled with higher risk score (RS) representing worse prognosis. Gene expression associated with poor (P) and good (G) in stage 1 and 2 HCC was identified (refer to presentation). RS (stage 1) = 5.997 - 0.589 × (Age at diagnosis−7.979E-06) - 4.818 × (P/G−0.009); RS (stage 2) = -5.704 - 0.780 × (Age at diagnosis−9.383E-06) + 7.228 × (P/G−0.004). Based on RS, pts were clustered into 2 groups in each stage - high and low RS groups, showing two KM curves with P < 0.05, HR = 3.213 (95% CI 2.212 – 4.347) in stage 1; HR = 2.733 (95% CI 2.131 – 3.426) in stage 2, confirming the validity of RS modeling. Analysis of immune profiles in high and low RS groups shows that expression of genes associated with immunosuppressive factors, desmoplastic reaction, neutrophils, and co-inhibitory factors of T-cells are higher in high RS group in both stages (p < 0.05). Conclusions: Machine learning-assisted mathematical modeling of RS and gene analysis identified TME-related genes and gene groups that are strongly associated with worse prognosis in stage 1 and 2 of HCC. RS could potentially prognosticate pts in the clinic with available genomic profiles.

Haemophagocytic lymphohistiocytosis (HLH) in patients with large B-cell lymphoma treated with standard of care (SOC) axicabtagene ciloleucel (Axi-cel)

8057

Background: HLH is a rare but serious complication of chimeric antigen receptor (CAR) T cell therapy, characterized by severe immune activation, and immune mediated multi-organ failure. Diagnosis is difficult in the context of cytokine release syndrome (CRS) and optimal treatment and outcomes are unclear. Methods: Retrospective, descriptive analysis of patients with relapsed/refractory LBCL treated with SOC axi-cel at MD Anderson Cancer Center between 01/2018 - 10/2019 (data cut-off 12/21/2019). Progression-free survival (PFS) defined as time from axi-cel infusion to progression/death or last follow-up. Diagnosis of HLH per HLH-2004 and CART cell therapy toxicity guidelines (Neelapu, 2018) Results: One hundred and five patients with relapsed/refractory LBCL included, 6 diagnosed with HLH. No significant difference in baseline characteristics, disease stage, international prognostic index or inflammatory markers at baseline between groups, with exception of platelet count which was lower in HLH group 116 [37-129] versus 141 [9-391] (p = 0.07). Development of HLH was early after CART cell infusion at a median 11 days [7 – 78 days] with 3 patients having bone marrow hemophagocytosis; all 6 had abnormalities in liver function tests, fibrinogen, triglycerides, and at least 1 ferritin level > 10,000. CART toxicity in HLH cohort: 4 patients experienced grade 0-1 CRS, and 1 with grade 2 CRS while 3 HLH patients experienced grade 3-4 IEC-associated neurotoxicity syndrome ( ICANS), and 2 patients had grade 0-1 ICANS. Five HLH patients treated with high dose steroids, and tocilizumab; anakinra administered in 2 patients. Four of 6 patients had resolution of HLH with treatment and didn’t require escalation to HLH specific therapy however 1 patient was treated with steroids/etoposide. PFS and overall survival (OS) were significantly shorter in HLH group, PFS 1 months vs 8 months, respectively (p < 0.001) and median OS 2 months vs not reached, respectively (p = 0.001) follow up 10 months (95% CI 8-12 months). One patient died of acute respiratory failure, 2 patients died of HLH and multi-organ failure without progressive disease (PD). Of 3 remaining patients, all had radiographic PD at day 30, 2 of whom died of PD. Conclusions: HLH is likely an underreported complication of CART cell therapy, and patients with HLH have significantly worse outcomes. In this series the majority of patients died of PD, not the syndrome itself. More information is necessary to design treatment strategies that won’t compromise CART outcomes.

Prognostic impact of dose, duration, and timing of corticosteroid therapy in patients with large B-cell lymphoma treated with standard of care axicabtagene ciloleucel (Axi-cel)

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Background: Corticosteroids are commonly used for management of severe toxicities associated with chimeric antigen receptor (CAR) T-cell therapy. However, it remains unclear whether the dose, duration, and timing of corticosteroid therapy may impact clinical efficacy of CAR T-cell therapy. Methods: This is a retrospective analysis of patients with relapsed or refractory LBCL treated with standard of care axi-cel at MD Anderson Cancer Center, Houston, Texas between 01/2018 and 05/2019 (data cut-off 12/21/2019). Progression-free survival (PFS) was defined as time from axi-cel infusion to progression/death or last follow-up, and the Breslow test was used for comparisons between subgroups. Results: One hundred patients with relapsed or refractory LBCL were included in the study, and 60 (60%) received corticosteroids for management of toxicities after axi-cel infusion. There was no significant difference in baseline tumor burden, disease stage or international prognostic index between the 2 groups. The median cumulative dexamethasone-equivalent dose was 186 mg (range, 8-1803 mg) and the median duration of corticosteroid treatment was 9 days (range 1-30); 45 (45%) patients started corticosteroid treatment between day 0 and 7, and 15 (15%) beyond day 7. After a median follow-up of 10 months (95% CI 8-10 months), median PFS was 8 months (95% CI, 3-13 months), and use of corticosteroids (any dose) showed a trend for association with shorter PFS (6 vs 9 months, p = 0.13). Use of high-dose corticosteroids (Quartiles (Q) 3-4, 195-1803 mg) significantly associated with shorter PFS (2 vs 9 months, p = 0.005). A trend for shorter PFS was observed among patients receiving corticosteroids for a prolonged time (Q3-Q4, 10-30 days) (5 vs 8 months, p = 0.12) and among patients starting corticosteroids within the first 7 days after axi-cel infusion (6 vs 11 months, p = 0.07). At most recent follow-up, 36 patients died, 28 of progression. Median overall survival has not been reached, and was significantly shorter among patients who received corticosteroids (13 vs not reached, p = 0.006). Conclusions: Early and prolonged use of high-dose corticosteroids is associated with early progression and death in patients with LBCL treated with axi-cel. Additional evaluation is needed to understand the mechanism underlying this association.

Role of extra corporeal methods for light chain removal on renal recovery in multiple myeloma: A systematic review

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Background: Renal impairment (RI) in Multiple Myeloma (MM) adversely affects the prognosis. Removing circulating free light chains via hemodialysis (HD) or plasma exchange (PLEX) along with chemotherapy can improve renal outcomes in MM. Methods: Per PRISMA guidelines a systematic search yielded 7311 articles since 2009 on 4 databases. After screening, 16 studies were included. Results: Main modalities were high cut off (HCO) HD, high flux (HF) HD, conventional HD and PLEX. N = 541 patients underwent HD/PLEX. 375/541 (69.3%) patients received HCO HD. In 2 RCTs, there was no significant difference in renal recovery (55.8% vs 51.6%; 41% vs 33%). The overall survival (OS) between the 2 groups was lower in the HCO group vs conventional HD (55.8% vs 76.6%) at 2 years while there was no significant difference in second study. Conclusions: HCO has failed to show promising efficacy with 2 RCTs failing to show statistical OS difference. There is paucity of data and further trials are needed. [Table: see text]