Predictive Factors of Overall Survival in Patients with Relapsed AL Amyloidosis Treated with Single Agent Daratumumab

Background: Two prospective phase II studies evaluated the efficacy of the anti-CD38 monoclonal antibody Daratumumab as a single agent (sDARA) in patients with relapsed AL amyloidosis and reported impressive hematologic and organ response rates. However, both studies included small number of patients and in one study sDARA was administered for 6 cycles (n=40) while in the other study, it was administered until hematologic progression, toxicity or for up to 24 months (n=22). Furthermore, predictive factors associated with hematologic and organ responses, and optimal duration of therapy remain unclear. Methods: We retrospectively studied the clinical and biological characteristics of patients with AL amyloidosis treated with sDARA, between April 2017 and December 2020, to identify factors associated with hematologic and organ response rates and impact on progression-free survival and overall survival (OS). Criteria for hematologic and organ response were defined according to the consensus criteria of ISA. Major organ deterioration progression-free survival (MOD-PFS) was used as a composite of endpoints from the time between sDARA initiation and whichever of the following occurred first: death, development of end stage cardiac or renal failure, or hematologic progression. OS was defined as the length of time between initiation of sDARA and the date of death or last follow-up. To account for immortal time bias, a landmark analysis for MOD-PFS and OS starting at the 12-month mark was performed to evaluate the impact of treatment duration on outcomes. Results: Eighty six patients with AL amyloidosis received sDARA. The median age was 67 years (range, 39-86) and 65% were male, 75% with lambda AL amyloidosis. Of the 86 patients, 38% had t(11;14) and 11% had 1q gain. At time of sDARA initiation, 35% of patients had >2 organs involved, including 22% with BU stage III (14% IIIa and 8% IIIb) and 13% with renal stage III disease. Majority (44%) of the patients received sDara as 2 nd line therapy, but 2% received as frontline, 21% as 3 rd line and 33% as 4 th line or more. Half of the patients (45%) were previously treated with HDM/SCT and 87% with proteasome inhibitor based regimen. Patients received a median of 12 cycles of sDARA (range 1-36) with a median follow-up time of 21.6 months (range 1.2-48.3). Hematologic CR and VGPR were achieved by 44% and 37% of patients, respectively and significantly associated with prolonged MOD-PFS and OS (Figure A and B). The median time to cardiac and renal responses were 6.8 months (range 0.9-12) and 6.7 months (range 1.8-42), respectively. At 12 months, cardiac and renal responses were observed in 47% and 61%, respectively and correlated with depth of hematologic response. The median OS and MOD-PFS were not reached (95% CI 40-NR) and 36 months (95% CI 28-NR), respectively. Achievement of cardiac response was associated with improved MOD-PFS (42 vs. 25 months; HR 0.25, 95% CI 0.08-0.78; p=0.01) and OS (NR vs 26 months; HR 0.20, 95% CI 0.04-0.89; p=0.02) and achievement of renal response was associated with improved MOD-PFS (NR vs. 13 months; HR 0.06, 95% CI 0.02-0.20; p<0.0001) and OS (NR vs. 25 months; HR 0.19, 95% CI 0.05-0.65; p=0.004). Importantly, presence of t(11;14) and number of previous lines of therapy did not impact MOD-PFS and OS. On an univariate analysis, several variables including dFLC >180 mg/L, bone marrow infiltration >10%, 24h proteinuria >3.5 g and NTproBNP >8500 pg/mL were significantly associated with lower MOD-PFS and OS, but only achievement of VGPR or CR and presence of 1q Gain were independently associated with MOD-PFS and OS (Figure C and D) on a multivariate analysis. Finally, on a landmark analysis, patients who received >12 cycles vs <12 cycles had significantly longer MOD-PFS (30 vs. 13 months; HR 0.47, 95% CI 0.31-0.72; p=0.0018)) and OS (NR vs. 15 months; HR 0.09, 95% CI 0.03-0.37; p<0.0001). Conclusion: sDARA confers very high rates of hematologic responses (81% of patients achieving >VGPR) in patients with relapsed AL amyloidosis and leads to prolonged OS and MOD-PFS, which is independent of the number of previous lines of treatment. Our data confirmed that achievement of hematologic response is a major predictor of OS and MOD-PFS in AL amyloidosis, and revealed that presence of 1q Gain is associated with lower response rate to sDARA. Longer duration of therapy (>12 cycles) with sDARA was associated with prolonged MOD-PFS and OS. Figure 1 Figure 1. Disclosures Sloan: Stemline: Honoraria; Abbvie: Honoraria; Astra Zeneca: Membership on an entity's Board of Directors or advisory committees; Pharmacosmos: Membership on an entity's Board of Directors or advisory committees. Sanchorawala: Karyopharm: Research Funding; Pfizer: Honoraria; Regeneron: Membership on an entity's Board of Directors or advisory committees; Takeda: Membership on an entity's Board of Directors or advisory committees, Research Funding; Prothena: Membership on an entity's Board of Directors or advisory committees, Research Funding; Proclara: Membership on an entity's Board of Directors or advisory committees; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Research Funding; Caleum: Membership on an entity's Board of Directors or advisory committees, Research Funding; Sorrento: Research Funding.

SIOP Ependymoma I: Final results, long term follow-up and molecular analysis of the trial cohort: A BIOMECA Consortium Study

Background: SIOP Ependymoma I was a non-randomised trial assessing event free and overall survival (EFS/OS) from non-metastatic intracranial ependymoma in children aged 3 to 21 years, treated with a staged management strategy. Chemotherapy efficacy in ependymoma is debated and therefore the response rate (RR) of subtotally resected (STR) ependymoma to vincristine, etoposide and cyclophosphamide (VEC) was an additional primary outcome. We report final results with 12-year follow-up and post hoc analyses of recently described biomarkers. Methods: 74 participants were eligible. Children with gross total resection (GTR) received radiotherapy, whilst those with STR received VEC before radiotherapy. DNA methylation and 1q status were evaluated, alongside hTERT, ReLA, Tenascin-C, H3K27me3 and pAKT expression. Results: Five- and ten-year EFS was 49.5% and 46.7%, OS was 69.3% and 60.5%. GTR was achieved in 33/74 (44.6%) and associated with improved EFS (p=0.003, HR=2.6, 95% confidence interval (CI) 1.4-5.1). Grade 3 tumours were associated with worse OS (p=0.005, HR=2.8, 95%CI 1.3-5.8). 1q gain and hTERT expression were associated with poorer EFS (p=0.003, HR=2.70, 95%CI 1.49-6.10 and p=0.014, HR=5.8, 95%CI 1.2-28 respectively) and H3K27me3 loss with worse OS (p=0.003, HR=4.6, 95%CI 1.5-13.2). DNA methylation profiles showed expected patterns. 12 participants with STR did not receive chemotherapy; a protocol violation. However, chemotherapy RR was 65.5% (19/29, 95%CI 45.7-82.1), exceeding a prespecified 45% RR. Conclusions: RR of STR to VEC exceeded the pre-specified criterion for efficacy. However, cases of inaccurate treatment stratification highlighted the need for rapid central review. Prognostic associations for 1q gain, H3K27me3 and hTERT were confirmed.

EPEN-04. SIOP EPENDYMOMA I: FINAL RESULTS, LONG TERM FOLLOW-UP AND MOLECULAR ANALYSIS OF THE TRIAL COHORT: A BIOMECA CONSORTIUM STUDY

Introduction Surgery and radiotherapy are established childhood ependymoma treatments. The efficacy of chemotherapy has been debated. We report final results of the SIOP Ependymoma I trial, with 12-year follow-up, in the context of a post-hoc analysis of more recently described biomarkers. Aims and Methods The trial assessed event free (EFS) and overall survival (OS) of patients aged three to 21 years with non-metastatic intracranial ependymoma, treated with a staged management strategy targeting maximum local control. The study also assessed: the response rate (RR) of subtotally resected (STR) disease to vincristine, etoposide and cyclophosphamide (VEC); and surgical operability. Children with gross total resection (GTR) received radiotherapy of 54 Gy in 30 daily fractions over six weeks, whilst those with STR received VEC before radiotherapy. We retrospectively assessed methylation and 1q status alongside hTERT, RELA, Tenascin C, H3K27me3 and pAKT expression. Results Between 1999 and 2007, 89 participants were enrolled, 15 were excluded with metastatic (n=4) or non-ependymoma tumours (n=11) leaving a final cohort of 74. Five- and ten-year EFS was 49.5% and 46.7%, OS was 69.3% and 60.5%. 1q gain was associated with poorer EFS (p=0.002, HR=3.00, 95%CI 1.49–6.10). hTERT expression was associated with worse five-year EFS (20.0% Vs 83.3%, p=0.014, HR=5.8). GTR was achieved in 33/74 (44.6%) and associated with improved EFS (p=0.006, HR=2.81, 95% confidence interval 1.35–5.84). There was an improvement in GTR rates in the latter half of the trial (1999-2002 32.4% versus 2003-2007 56.8%). Despite the protocol, 12 participants with STR did not receive chemotherapy. However, chemotherapy RR was 65.5% (19/29, 95%CI 45.7–82.1). Conclusions VEC exceeded the pre-specified RR of 45% in children over three years with STR intracranial ependymoma. However, cases of inaccurate stratification at treating centres highlights the need for rapid central review. We also confirmed associations between 1q gain, hTERT expression and outcome.

Carfilzomib-based induction/consolidation with or without autologous transplant (ASCT) followed by lenalidomide (R) or carfilzomib-lenalidomide (KR) maintenance: Efficacy in high-risk patients.

8002 Background: Cytogenetic abnormalities (CA) are one of the most powerful prognostic factors in multiple myeloma (MM). In the FORTE study, carfilzomib-lenalidomide-dexamethasone induction/consolidation with ASCT (KRd_ASCT) significantly improved progression-free survival (PFS) vs KRd without ASCT (KRd12, HR 0.64) or carfilzomib-cyclophosphamide-dexamethasone (KCd) plus ASCT (KCd_ASCT, HR 0.53). KR maintenance significantly improved PFS vs R (HR 0.63). Methods: MM patients (pts) were randomized to KRd_ASCT vs KCd_ASCT vs KRd12 and, thereafter, to KR vs R maintenance. Subgroup analyses according to FISH evaluated the impact of each single high-risk (HiR) CA [del17p, t(4;14), t(14;16), del1p and 1q gain (3 copies) or amp1q (≥4 copies)] and that of combined CA, defining HiR by the presence of ≥1 HiR CA and double-hit (DH) by the presence of ≥2 HiR CA. Pts negative for all the HiR CA were considered at standard risk (SR). The primary objective was the impact of treatment on PFS according to pt risk. Results: 396 out of 474 enrolled pts were included in the analysis with complete FISH data: 243 HiR, 105 DH and 153 SR. Among HiR pts, 60 had del17p, 65 t(4;14), 20 t(14;16), 44 del1p, 126 1q gain and 49 amp1q. SR pts benefited from intensification with KRd_ASCT vs KRd12 (HR 0.47, p = 0.05) and KCd_ASCT (HR 0.38, p = 0.01), with a 4-year PFS of 80%, 67% and 57%, respectively. In HiR pts, KRd_ASCT improved PFS vs KRd12 (HR 0.6, p = 0.04) and KCd_ASCT (HR 0.57, p = 0.01), with a 4-year PFS of 62%, 45% and 45%, respectively. The advantage with KRd_ASCT vs KRd12 (HR 0.53, p = 0.07) and KCd_ASCT (HR 0.49; p = 0.03) was also observed in DH pts (4-year PFS 55%, 31% and 33%, respectively). Analyses by single CA were limited by the small number of pts in each subgroup, but a trend towards a PFS benefit from KRd_ASCT vs KRd12 was seen in pts with del17p (HR 0.61, p = 0.3), t(4;14) (HR 0.59, p = 0.2) and 1q gain (HR 0.45, p = 0.02). In pts with del1p, KRd_ASCT (HR 0.24, p = 0.06) and KRd12 (HR 0.33, p = 0.09) showed superiority over KCd_ASCT, while amp1q pts had the worst outcome regardless of treatment (KRd_ASCT vs KCd_ASCT, HR 1.16, p = 0.73; KRd12 vs KCd_ASCT, HR 1.34, p = 0.45). KR improved PFS vs R in SR (3-year PFS 90% vs 73%, HR 0.42, p = 0.06), HiR (3-year PFS 69% vs 56%, HR 0.6, p = 0.04) and DH pts (3-year PFS 67% vs 42%, HR 0.53, p = 0.1). Despite the small subgroups, a beneficial trend with KR vs R was observed in pts with del17p (HR 0.59, p = 0.37), t(4;14) (HR 0.59, p = 0.3), 1q gain (HR 0.54, p = 0.07) and del1p (HR 0.23, p = 0.08), while amp1q pts showed the worst outcome and no benefit from KR vs R (HR 0.83, p = 0.7). Conclusions: KRd_ASCT and KR maintenance are highly effective in SR and also in HiR and DH pts, with impressive 4-year PFS from diagnosis (KRd_ASCT: HiR 62%, DH 55%) and 3-year PFS from maintenance (KR: HiR 69%, DH 67%), thus supporting their use in HiR pts, who represent an unmet medical need. Clinical trial information: NCT02203643.

Aberrations of Chromosomes 1 and 16 in Breast Cancer: A Framework for Cooperation of Transcriptionally Dysregulated Genes

Derivative chromosome der(1;16), isochromosome 1q, and deleted 16q—producing arm-level 1q-gain and/or 16q-loss—are recurrent cytogenetic abnormalities in breast cancer, but their exact role in determining the malignant phenotype is still largely unknown. We exploited The Cancer Genome Atlas (TCGA) data to generate and analyze groups of breast invasive carcinomas, called 1,16-chromogroups, that are characterized by a pattern of arm-level somatic copy number aberrations congruent with known cytogenetic aberrations of chromosome 1 and 16. Substantial differences were found among 1,16-chromogroups in terms of other chromosomal aberrations, aneuploidy scores, transcriptomic data, single-point mutations, histotypes, and molecular subtypes. Breast cancers with a co-occurrence of 1q-gain and 16q-loss can be distinguished in a “low aneuploidy score” group, congruent to der(1;16), and a “high aneuploidy score” group, congruent to the co-occurrence of isochromosome 1q and deleted 16q. Another three groups are formed by cancers showing separately 1q-gain or 16q-loss or no aberrations of 1q and 16q. Transcriptome comparisons among the 1,16-chromogroups, integrated with functional pathway analysis, suggested the cooperation of overexpressed 1q genes and underexpressed 16q genes in the genesis of both ductal and lobular carcinomas, thus highlighting the putative role of genes encoding gamma-secretase subunits (APH1A, PSEN2, and NCSTN) and Wnt enhanceosome components (BCL9 and PYGO2) in 1q, and the glycoprotein E-cadherin (CDH1), the E3 ubiquitin-protein ligase WWP2, the deubiquitinating enzyme CYLD, and the transcription factor CBFB in 16q. The analysis of 1,16-chromogroups is a strategy with far-reaching implications for the selection of cancer cell models and novel experimental therapies.

Focal amplification of FAL1, an oncogenic enhancer lncRNA mapping to chromosome 1q is associated with dysregulated BMI1/p21 axis and an adverse event in intracranial ependymomas

Gain of chromosome 1q locus is a common cytogenetic feature associated with intracranial ependymomas; however, candidate non-coding RNAs on this locus have not been identified. Recent studies have reported somatic copy number alterations for long non coding RNA (lncRNA) FAL1/FALEC residing on chromosome 1q to stabilize BMI1, an epigenetic repressor and PRC1 component, leading with to downregulation of p21/CDKN1A tumor suppressor gene. We aimed to study the role of FAL1 in ependymomas, its association with 1q gain, BMI1/p21 regulatory axis and clinicopathological parameters. Using SNP array analysis (GSE32101), 31% (discovery cohort) and 63.8% (in-house cohort) showed amplification/gain of FAL1 locus with higher prevalence in intracranial tumors. Copy number gain of FAL1 locus was significantly associated with increased FAL1 (p=0.003) and BMI1 (p=0.007) levels, and reduced p21 (p=0.001) expressions. Interestingly, gain of FAL1 locus and FAL1 transcripts did not show any association with 1q gain or RELA fusions. Subcellular localization reported FAL1 to be expressed in nuclear compartment in ependymomas. Chromatin immunoprecipitation-qPCR demonstrated in-vivo binding of BMI1 at p21 promoter locus with BMI1 target genes to be enriched in cell architecture related pathways. A 3-tier survival analysis between FAL1 gain and increased expression levels of FAL1 and BMI1 correlated with poor outcome in our cohort. Ours is the first study demonstrating gain of FAL1 locus and its interplay with the BMI1/p21 axis in intracranial ependymomas. Further studies into this epigenetic regulatory mechanism will unravel novel driver mutations in intracranial ependymomas

Ultra high-risk PFA ependymoma is characterized by loss of chromosome 6q

Background Within PF-EPN-A, 1q gain is a marker of poor prognosis, however, it is unclear if within PF-EPN-A additional cytogenetic events exist which can refine risk stratification. Methods Five independent non-overlapping cohorts of PF-EPN-A were analyzed applying genome wide methylation arrays for chromosomal and clinical variables predictive of survival. Results Across all cohorts, 663 PF-EPN-A were identified. The most common broad copy number event was 1q gain (18.9%), followed by 6q loss (8.6%), 9p gain (6.5%), and 22q loss (6.8%). Within 1q gain tumors, there was significant enrichment for 6q loss (17.7%), 10q loss (16.9%) and 16q loss (15.3%). The 5-year progression free survival (PFS) was strikingly worse in those patients with 6q loss, with a 5-year PFS of 50% (95%CI 45-55%) for balanced tumors, compared with 32% (95%CI 24-44%) for 1q gain only, 7.3% (95%CI 2.0-27%) for 6q loss only and 0 for both 1q gain and 6q loss (p=1.65x10 -13 ). After accounting for treatment, 6q loss remained the most significant independent predictor of survival in PF-EPN-A but is not in PF-EPN-B. Distant relapses were more common in 1q gain irrespective of 6q loss. RNA-sequencing comparing 6q loss to 6q balanced PF-EPN-A suggests that 6q loss forms a biologically distinct group. Conclusions We have identified an ultra high-risk PF-EPN-A ependymoma subgroup, which can be reliably ascertained using cytogenetic markers in routine clinical use. A change in treatment paradigm is urgently needed for this particular subset of PF-EPN-A where novel therapies should be prioritized for upfront therapy.

Prognostic value of integrated cytogenetic, somatic variation, and copy number variation analyses in Korean patients with newly diagnosed multiple myeloma

Background To investigate the prognostic value of gene variants and copy number variations (CNVs) in patients with newly diagnosed multiple myeloma (NDMM), an integrative genomic analysis was performed. Methods Sixty-seven patients with NDMM exhibiting more than 60% plasma cells in the bone marrow aspirate were enrolled in the study. Whole-exome sequencing was conducted on bone marrow nucleated cells. Mutation and CNV analyses were performed using the CNVkit and Nexus Copy Number software. In addition, karyotype and fluorescent in situ hybridization were utilized for the integrated analysis. Results Eighty-three driver gene mutations were detected in 63 patients with NDMM. The median number of mutations per patient was 2.0 (95% confidence interval [CI] = 2.0–3.0, range = 0–8). MAML2 and BHLHE41 mutations were associated with decreased survival. CNVs were detected in 56 patients (72.7%; 56/67). The median number of CNVs per patient was 6.0 (95% CI = 5.7–7.0; range = 0–16). Among the CNVs, 1q gain, 6p gain, 6q loss, 8p loss, and 13q loss were associated with decreased survival. Additionally, 1q gain and 6p gain were independent adverse prognostic factors. Increased numbers of CNVs and driver gene mutations were associated with poor clinical outcomes. Cluster analysis revealed that patients with the highest number of driver mutations along with 1q gain, 6p gain, and 13q loss exhibited the poorest prognosis. Conclusions In addition to the known prognostic factors, the integrated analysis of genetic variations and CNVs could contribute to prognostic stratification of patients with NDMM.