ALBERT

Description: INTRODUCTION. Bortezomib- and/or lenalidomide-based combinations are standard initial approaches in transplant (ASCT) ineligible NDMM. Different studies confirmed the advantages of continuous treatment. Despite the benefits of bortezomib maintenance, the parenteral administration and the risk of peripheral neuropathy (PN) limit its long-term use. The oral proteasome inhibitor (PI) Ixazomib plus Lenalidomide-dexamethasone was effective and well tolerated at diagnosis or relapse. The need for a convenient and well tolerated PI-based frontline therapy for an extended duration with minimal cumulative toxicity remains an unmet need for the elderly. In this prospective, multicenter, phase II randomized study, we assessed Ixazomib in combination with dexamethasone, Cyclophosphamide, Thalidomide or Bendamustine, followed by Ixazomib maintenance in ASCT-ineligible NDMM. METHODS. NDMM patients (pts) ≥65 years old or younger ASCT-ineligible could be enrolled. Treatment consisted of nine 28-day induction cycles of Ixazomib 4 mg on days 1,8,15 and dexamethasone 40 mg on days 1,8,15,22 (Id) or combined with Cyclophosphamide 300 mg/m2 orally on days 1,8,15 (ICd) or plus Thalidomide 100 mg/day (ITd) or plus Bendamustine 75 mg/m2 iv on days 1,8 (IBd); followed by maintenance with Ixazomib 4 mg on days 1,8,15 until progression. Because the study included the novel drug Ixazomib, dual stopping rules combining efficacy (at least very good partial response [VGPR] rate), and safety (predefined toxicity possibly related to Ixazomib) were planned and analyzed in a cohort of 5 patients in each arm during the first 4 cycles. Here we report the results of the cohort analysis during the first 4 cycles and the efficacy and safety analysis during induction treatment. RESULTS. In February 2017, the protocol was amended due to a low enrolment and the IBd arm, the only one including an iv drug, was closed. After closing this arm, all the other all oral arms continued the enrolment. Overall, 175 pts were enrolled (Id 42, ICd 61, ITd 61, and IBd 11 pts) and 171 pts started treatment. Median age was 74 years, 20% of pts had high risk cytogenetics, 44% were fit, 30% intermediate and 26% frail, according to the IMWG frailty score. Median follow-up was 13.2 months (IQR 8.9-20.7). During the first 4 cycles, at least VGPR rate was 24% with Id, 33% with ICd, 31% with ITd and 18% with IBd. In March 2018, after the analysis of the 4th cohort, the Id arm was closed due to high risk of inefficacy. Overall response rate (ORR) during induction was 73%, VGPR was 39%. ≥VGPR rates were 24% in Id, 48% in ICd, 43% in ITd and 27% in IBd. Median time to first response was 2.4 and to the best response 4 months. Responses were comparable according to cytogenetics: in high risk pts, ORR was 77%, ≥VGPR 46% and ≥nCR 17% as compared to 71%, 36% and 18% in standard risk pts (p=0.53, p=0.33 and p=1, respectively). Response rates were also comparable according to frailty status: in frail pts, ORR was 73%, ≥VGPR 36% and ≥nCR 11% as compared to 75%, 40% and 17% in intermediate and 70%, 40% and 22% in fit pts (p=0.78, p=0.90 and p=0.32, respectively). Median number of induction cycles was 9 (IQR 5-9); 93 (53%) pts completed induction treatment and 14 (8%) pts are still on induction treatment. During the first 4 cycles, hematologic toxicity was limited, and non-hematologic toxicity manageable. The most frequent G3-4 adverse event (AE) was rash in ITd arm (11%); discontinuation rate due to toxicity was 6%. During induction, the rate of at least 1 hematologic G≥3 AE was 11% and at least 1 non-hematologic G≥3 AE was 44%. The most frequent G≥3 AEs were neutropenia (8%), gastrointestinal (9%), infections (11%), neurologic (11%) and dermatologic (6%). G3-4 thrombocytopenia (3%) and PN (5%) were limited. Ixazomib dose reduction due to AEs was required in 15% of pts. The rate of non-hematologic AEs was slightly higher in ITd arm (37% in Id, 37% in ICd, 53% in ITd, 55% in IBd). Early death rate (

Description: INTRODUCTION In newly diagnosed Multiple Myeloma (MM) patients (pts), Copy Number (CN) losses of chromosome 17p13, carrying the TP53 tumor-suppressor gene, are strong predictors of poor outcomes. On the contrary, the prognostic relevance of TP53 mutations at the onset of the disease is less clear, due to the very limited frequency of clonal lesions, as revealed by Sanger sequencing. To address this poorly investigated issue, we used an ultra-deep sequencing (UDS) approach to characterize the TP53 structural architecture in both newly diagnosed and relapsed MM pts and to assess the prognostic role and evolution over time of small TP53 mutated sub-clones. SAMPLES AND METHODS A cohort of 99 newly diagnosed MM pts treated up-front with bortezomib-based regimens and autologous stem cell transplantation, was included in this molecular study. In 29 cases, samples were collected both at diagnosis and at relapse(s). DNA was obtained from CD138+ highly purified plasma cells. TP53 gene mutational status was analysed by using an amplicon-targeted UDS approach (GSJ, 454 Roche Life Sciences). In order to discriminate between low frequency sub-clonal TP53 variants and sequencing errors, sequencing raw data were filtered according to cut-off values based on different ranges of sequences' coverage depth. Additional filters were also applied, based on both quality and biological cut-offs, to obtain a final confident list of variants. Analysis of CN alterations (CNAs) was performed by SNPs array and results analysed with ChAS software. RESULTS With a median coverage of 1386X, a list of 129 correctly called TP53 variants (either missense, or nonsense or splice ones), including 20 INDELs, was detected. Only deleterious and N/A variants (according to SIFT classification) were included in the list. Most newly diagnosed MM pts (55%) carried at least one TP53 sub-clonal variant (on average 1.08 variants per pts), with 45/99 (45%) carrying non-mutated TP53. Pts carrying TP53 sub-clonal variants bared also TP53 CN hemizygous losses (20%), CKS1B gains (56%) and cdkn2c losses (14%). According to TP53 sub-clonal mutational load, pts were stratified in two sub-groups, including 28 pts with ≥2 (high load) and 71 with

Description: Allogeneic stem cell transplantation (allo-SCT), which provides a tumor-free graft, is an alternative approach to autologous transplantation for multiple myeloma (MM) that offers the possibility of cure through a graft vs myeloma effect (GVM). However, the inherent non relapse mortality (NRM) and the high post-transplant relapse rate are the major shortcomings of this strategy which continues to have a controversial role in MM treatment. To highlight the long-term clinical outcomes of allo-SCT, we performed a retrospective analysis on 102 patients (pts) with MM who received at our Institution either a myeloablative (MA) (74 pts) or a non-myeloablative (NMA) (28 pts) conditioning regimen between 1990 and 2014. The MA regimen consisted in low dose TBI and cyclophosphamide (cyclo) ± melphalan (mel) or busulfan-cyclo. The NMA regimen was mel-fludarabine. Graft versus host disease (GVHD) prophylaxis consisted in cyclosporine + methotrexate (83%) or mycophenolate (17%), with the addition of thymoglobulin for unrelated or related female vs male recipient donors. The median age was 42 yrs (IQR 38-47), 60% pts were male. The hematopoietic cell donors were sibling in 77 pts and unrelated in 25, while the source of stem cells was peripheral blood in 65 and bone marrow in 37 pts. Fifty-six pts received allo-SCT as first-line therapy, 31 as second-line and 13 as third or fourth-line. Median time from diagnosis to allo-SCT was 22 months. Response status at the time of transplant was at least PR in 63% of the pts, including ≥ VGPR in 36% and CR in 12%. Overall, the response rate after allo-SCT was as follows: CR 58%, VGPR 19%, PR 18%. Median CR duration was 10 years (44% at 15 years). The incidence of acute grade II-IV and III-IV GVHD was 25% and 15%, respectively. The incidence of all grades chronic cGVHD was 48%, grade ≥2: 24%, with a median onset time of 178 days. By competitive risks analysis, the cumulative incidence of cGVHD at 1 and 3 years was 20% and 32%, respectively. On univariate analysis, the gender combination of female donor-male patient resulted in significantly higher incidence of cGVHD (sub hazard ratio, SHR, 2.3, P= 0.03). The cumulative incidence of NRM was 6.6% at 100 days, 11% at 1 year and 14.4% at 3 years, with lack of statistically significant relationship with the conditioning regimen. By univariate analysis, 〈 PR prior to allo-SCT (SHR 2.8) and all grades cGVHD (SHR 4.6) were significantly associated with an increased NRM. By competitive risks analysis, the cumulative incidence of relapse was 50% at 5 years, 58% at 10 years and 59% at 15 years. On univariate analysis, sibling donor (SHR 0.54, P=0.047), all grades cGVHD (SHR 0.5, P=0.011) and ≥VGPR after allo-SCT (SHR 0.38, P=0.001) were significantly associated with extended time to progression. All grades cGVHD (SHR 0.43, P=0.005) and ≥VGPR after allo-SCT (SHR 0.36, P= 0.001) were independent predictors for a lower risk of progression on multivariate analysis. With a median follow-up of 13 years, overall survival (OS) was 43% at 5 years and 34% at 10 years. In univariate analysis, low ISS stage at diagnosis, sibling donor, absence of female donor-male patient gender combination, ≥VGPR prior to allo-SCT and first-line allo-SCT were significantly related to OS. Multivariate analysis confirmed an OS benefit for having a sibling donor (HR 0.30, P

Description: Background Although remarkable advances have been achieved in MM therapy, mainly thanks to the introduction of novel-agent-based regimens, the disease remains incurable. Neoplastic CD138+ plasma cells are the hallmark of MM: both their expansion in the bone marrow (BM) and the production of monoclonal immunoglobulin (Ig) are responsible for the clinical manifestation of the disease. However, the existence of a Myeloma Propagating Cells (MPCs) has been proposed as a major cause of MM drug-resistance, leading to relapse. Several studies support the hypothesis that MPCs are phenotypically close to memory B cells residing in the CD138- compartment; however, very little is known concerning their molecular characteristics. Here we present an extensive molecular characterization of clonotypic CD19+ B cells clones obtained from newly diagnosed MM patients (pts), in order to recognize biological pathways possibly explaining the malignant clone’s persistence. Methods CD138+ and CD138- cell fractions were collected from BM and peripheral blood (PBL) of 50 newly diagnosed MM pts. CD19+ B cell and CD27+ memory B cell populations were isolated from CD138- cell fraction. Clonogenic assays were performed by plating cell fractions obtained from RPMI-8226 and NCI-H929 cell lines. The molecular characterization included: IgH gene rearrangement Sanger sequencing; analysis of the whole spectrum of genomic aberrations and gene expression profiling, by Affymetrix 6.0 SNPs array and HG-U133 Plus 2.0 microarray, respectively. Results Clonogenic assays showed that CD138- cells, plated on conditioned media, were able to form colonies after two weeks of culture more efficiently than CD138+ cells. By VDJ gene rearrangement sequencing, a clonal relationship between the CD138+ clone and the memory B ones was confirmed. SNPs arrays showed that both BM and PBL CD138+ cell fractions carried exactly the same genomic macro-alterations. On the contrary, in the CD138-19+27+ cell fractions from BM and PBL any macro-alteration was detected, whereas several micro-alterations (median number per sample: 32 amplifications and 16 losses, range: 8-122 Kb, average markers per region: 50) unique of the memory B cells clone were highlighted. An enrichment analysis revealed the involvement of genes affected by losses (17 genes) in both DNA repair mechanisms and transcriptional regulation and the involvement of genes affected by gains (46 genes) in both the negative regulation of apoptosis and the angiogenesis. Interestingly, KRAS, WWOX and XIAP genes, renown to be involved in MM pathogenesis, are located in the amplified regions in the immature cells. Moreover, several LOH regions were described, which covered at least 106 tumor suppressor genes involved in MM and leukemia (including TP53, CDKN2C and RASSF1A). Transcriptome profiles analysis of the CD19+ cell fractions highlighted pathways suggesting a possible involvement of immature cells in MM pathogenesis. The gene expression profiles of 20 MM CD19+ cells samples (12 from PBL, 8 from BM) were compared both to their normal counterpart and to the mature CD138+ cell fractions. In particular, unsupervised analysis by hierarchical clustering discriminated the differential expression of 11480 and 11360 probes in the PBL and BM CD19+ clones, respectively (2; FDR=0,05; p

Description: Background: AML is a heterogeneous disease. The karyotype provides important prognostic information that influences therapy and outcome. Identification of AML patients (pts) with poor prognosis such as those with complex karyotype (CK) has great interest and impact on therapeutic strategies. TP53 is the most frequently mutated gene in human tumours. TP53 mutation rate in AML was reported to be low (2.1%), but the incidence of TP53 mutations in AML with a complex aberrant karyotype is still debated. Aims: To investigate the frequency of TP53 mutations in adult AML pts, the types of mutations, the associations with recurrent cytogenetic abnormalities and their relationship with response to therapy, clinical outcome and finally their prognostic role. To this aim, we focused on a subgroup of TOT/886 AML pts treated at the Serˆgnoli Institute of Bologna between 2002 and 2013. Patients and Methods: 886 AML patients were analysed for morphology, immunophenotype, cytogenetic and for a panel of genetic alterations (FLT3, NPM1, DNMT3A, IDH1, IDH2 mutations, WT-1 expression, CBF fusion transcripts). Of these, 172 adult AML pts were also examined for TP53 mutations using several methods, including Sanger sequencing, Next-Generation Deep-Sequencing (Roche) and HiSeq 2000 (Illumina) platform. 40 samples were genotyped with Genome-Wide Human SNP 6.0 arrays or with CytoScan HD Array (Affymetrix) and analysed by Nexus Copy Numberª v7.5 (BioDiscovery). Results: Of the 886 AML patients, 172 pts were screened for TP53 mutations. Sanger sequencing analysis detected TP53 mutations in 29/172 AML patients with 36 different types of mutations; seven pts (4%) had 2 mutations. At diagnosis, the median age of TP53 mutated and wild type patients was 68 years (range 42-86), and 65 years (range 22-97) respectively. Median WBC count was 8955/mmc (range 580-74360/mmc) and 1240/mmc (range 400-238000/mmc). Conventional cytogenetics showed that: a) 52 pts (30,2%) had 3 or more chromosome abnormalities, i.e. complex karyotype; b) 71 (41,3%) presented with one or two cytogenetic abnormalities (other-AML); c) 34 pts (19,8%) had normal karyotype. Most of the TP53 mutated pts (23/29, 79.3%) had complex karyiotype, whereas only 6/29 mutated pts had “no complex Karyotype” (21% and 3% of the entire screened population, respectively). Overall, TP53 frequency was 44.2% in the complex karyotype group, suggesting a pathogenetic role of TP53 mutations in this subgroup of leukemias. As far as the types of TP53 alterations regards, the majority of mutations (32) were deleterious.. Copy Number Alterations (CNAs) analysis performed on 40 cases by Affymetrix SNP arrays showed the presence of several CNAs in all cases: they ranged from loss or gain of the full chromosome (chr) arm to focal deletions and gains targeting one or few genes involving macroscopic (〉1.5 Mbps), submicroscopic genomic intervals (50 Kbps - 1.5 Mbps) and LOH (〉5 Mbps) events. Of relevance, gains located on chr 8 were statistically associated with TP53 mutations (p = 0.001). In addition to the trisomy of the chr 8, others CNAs, located on chromosomes 5q, 3, 12, 17 are significantly associated (p = 0.05) with TP53 mutations. WES analysis was performed in 37 pts: 32 TP53 were wt while 5 pts were TP53 mutated. Interestingly, TP53 mutated patients had more incidence of complex karyotype, more aneuploidy state, more number of somatic mutations (median mutation rate 30/case vs 10/case, respectively). Regarding the clinical outcome, as previously reported (Grossmann V. et Al. Blood 2013), alterations of TP53 were significantly associated with poor outcome in terms of both overall survival (median survival: 4 and 31 months in TP53 mutated and wild type patients, respectively; p

Description: Introduction The differentiation status plasticity of Multiple Myeloma (MM) plasma cells (PCs) is an adaptive strategy that might confer a specific fitness to tumour cells, enabling their interaction with an evolving microenvironment. Therefore, proliferation rates of MM clones are not constant, and the immunophenotypic profile of the most skilled MM PCs might be the expression of specific genetic and genomic programs, that emerge under the therapeutic pressure and promote tumour development. However, the genomic background that supports any diverse plasma cell differentiation phenotypes has not yet been inferred. Aim To correlate the genetic and genomic background with the immunophenotypic profile of MM clones at diagnosis, in order to stratify patients (pts) according to a Maturation Index, and ultimately to evaluate the impact of this stratification on the disease outcome. Patients and Methods 117 newly diagnosed MM (NDMM) pts, mostly treated up-front with a proteasome inhibitor (PI) -based treatment, were included in the study. For each pts, both neoplastic PCs and CD19+ B cells compartments were characterized by 8-color multi-parameter flow cytometry analysis, combining CD138-PE, CD38-PE-Cy7, CD56-APC-Cy7, CD20-APC, CD19-FITC, CD27-APC, CD45-PerCp, CD28-APC, CD117-FITC, CD28-APC, CD81-APC, IgK-APC and IgL-FITC. In a subgroup of pts, both a SNP array profile for copy number alterations (CNAs) and a 25-genes targeted mutational panel were assessed in CD138+ PCs. A custom ddPCR assay was also employed to evaluate through a 10-Hh gene signature the self-renewal status of PCs. Results In order to define a Maturation Index, pts were evaluated at different levels of heterogeneity for: a) differential expression of CD19/CD81 markers; b) level of chromosomal instability (CIN) and point mutations; d) self-renewal status. Based on the co-expression of CD19 and CD81 markers, pts were stratified in 3 different subgroups, recapitulating a progressive PC maturation process: the most immature, which included pts with CD19+/CD81+ PCs (18/117 = 15%), the intermediate, including CD19-/CD81+ PCs (42/117 = 36%) and the most mature, including CD19-/CD81- PCs (57/117 = 49%). The advanced PC differentiation status characterizing this latter subgroup was further confirmed by the high expression of CD28 and CD44, and the reduced expression of CD20, CD27 and CD45, commonly associated with less mature stages of the disease (p

Description: Introduction: The role of serum free light chain (sFLC) assay for monitoring immunoglobulin (Ig) secretory multiple myeloma (Ig-MM) remains an area of debate. IMWG guidelines (Durie et al. Leukemia 2006) recommend the use of electrophoresis (EP) and immunofixation (IF) for definitions of response and progressive disease (PD), while the measurement of sFLC is required only to fulfill criteria for stringent complete response. Aims: We aimed at evaluating the prognostic impact of sFLC levels during monitoring of Ig-MM. Methods: We analyzed all consecutive Ig-MM patients (pts) who received at our Centre a first line novel agent-based therapy between October 2006 and December 2018, and for whom sFLC data by BN II nephelometer, along with serum and urine EP plus IF, were available at diagnosis and every 3-4 months until the last contact date. Criteria for response and PD were those established by the IMWG. IMWG criteria for PD in oligo/non-secretory MM were used to identify an increase in sFLC levels. sFLC escape (sFLCe) was defined as an increase in sFLC, without any IMWG criteria of PD. To evaluate the prognostic role of rising sFLC, sFLCe was considered as an event for outcomes after relapse. Second time to progression/sFLCe (2nd TTPe) was the time from the date of first PD or sFLCe to that of second PD or sFLCe, while OS after progression/sFLCe (OS after Pe) was calculated from first PD or sFLCe to the date of death. Results: A total of 339 pts were identified. At baseline, 311 (92%) pts had an abnormal sFLC ratio (sFLCR) and 231 (68%) a sFLC measurable disease defined by an abnormal sFLCR and involved sFLC ≥100 mg/L. First-line treatments included proteasome-inhibitors (PI) (42%), immunomodulators (IMiDs) (13%), or both these agents (45%). Autotransplant was performed in 48% of pts. Overall, 148 (44%) pts achieved a complete response (CR) and 198 (60%) achieved (or maintained) a normal sFLCR. With a median follow-up of 54.1 (IQR 25.0-83.7) months (mos), median PFS and OS were 35.9 and 97.9 mos. The presence at baseline of a sFLC measurable disease was associated with worse PFS (median 31.5 vs 45.6 mos, HR=1.58, p=0.004) and OS (64.5% vs 83.3% at 54 mos, HR=1.98, p=0.003), while sFLCR normalization predicted for extended PFS (median 45.3 vs 16.8 mos, HR=0.21, p

Description: Multiple Myeloma (MM) maintenance therapy is a low intensive, prolonged treatment, commonly administered to newly diagnosed patients (pts) at the end of fixed-time, front-line regimens. Lenalidomide (LEN) is considered the best available maintenance option for MM able to prolong pts survival. However, the actual benefits or disadvantages of a LEN-based continuous maintenance and its potential role as selective pressure able to induce genomic changes are still unclear. The identification of specific therapy-driven modifications has been so far prevented by the scarce number of homogeneously-treated cohorts of pts with paired samples (diagnosis, D and relapse, R). In this study we estimated the role of LEN maintenance therapy in eliciting genomic changes in a cohort of MM pts homogeneously up-front treated with PI-based regimens. Whole genome Copy Number Aberrations (CNAs) landscape was obtained by SNPs array in 54 pts whose BM-CD138+ were collected both at D and at first R. Pts had an high-risk (HR) disease, as defined both by the presence of HR cytogenetic aberration at baseline in 81% of pts and by the 29 m median TTP. RawCopy 1.10 was used for the segmentation of SNPs array signals; samples' purity was adjusted by using manually reviewed ASCAT solutions. A custom gene-level CN calling approach was set up, to match every gene's CN value at D and R, thus generating genomic evolutive patterns based on changes of these values. Finally, high-risk genomic loci were computed using GISTIC 2.0_v7 to derive focal regions with oncogene and/or tumor suppressor genes relevant for MM biology. After induction therapy, 31/54 pts were treated with HD chemotherapy followed by either single or double ASCT; LEN maintenance therapy was then offered both to 20/31 auto-transplanted and to 6/23 not auto-transplanted pts. Three main evolutive trajectories (linear L, drift D, and branching B) were defined according to the CN changes' direction, reflecting a putative positive, negative, or both positive and negative selective pressure, respectively. A fourth, stable (S) trajectory was also observed, characterized by the absence of CN changes between D and R. Overall, 29, 15 and 10 pts relapsed with B/D, L and S pattern, respectively; at R, all LEN-treated pts quantitively and qualitatively changed their sub-clonal architecture: a B/D evolutive pattern characterized 70% of pts. By contrast, genome remained mostly stable in 61% of not-treated pts. We then focused on CN changes of specific chromosomal regions and/or genomic loci, whose prognostic role has been already established in MM (i.e. CN losses of TP53 on chr17p, RB1 on chr13q, CYLD on chr16q, CDKN2C and FAM46C on chr1p; CN gain of CKS1B on chr1q). When present at D these CNAs tended to persist throughout the disease course regardless of whether pts received or not maintenance. The emersion of any of these CNAs at R was widely observed both in pts receiving or not maintenance, whereas a negative selective pressure over them was more likely to occur in pts receiving maintenance, as compared to the others (50% vs 11% of B/D trajectories in LEN-treated vs not-treated pts, respectively). Strikingly, in LEN-treated pts, the extension of both TTP and OS was favored by the extinction and/or negative selection of the HR CNAs (B/D patterns), and shortened by their stability or positive selection (L/S patterns) (median TTP 46 vs 32 m HR=3,6 CI 1,2-10,6, p=0.01; median OS 111 vs 63 m HR 5,7 CI 1,1-32,4, p=0.04 in B/D vs L/S pts, respectively). On the contrary, the absence of maintenance selective pressure seemed to affect neither the evolution trajectory, nor the clinical course of not-treated pts (fig 1). The extinction of sub-clones carrying HR lesions in pts receiving maintenance therapy is likely to be associated to the negative selection exerted by the therapy itself. This might explain the extended survival of pts receiving maintenance and relapsing with B/D evolution patterns, as compared to that of pts whose genomic landscape either tended to remain stable or let the prevalent emersion of HR genomic features. On the contrary, the sub-clonal architecture of pts not receiving maintenance seemed to randomly evolve, due to the absence of a specific therapy-related selective pressure. Overall, information on the genomic changes occurring throughout the disease course might be relevant for the recognition of pts most benefitting from a continuous therapy. Thanks to AIRC_IG2014-15839, RF-2016-02362532 Disclosures Zamagni: Takeda: Honoraria, Speakers Bureau; Sanofi: Honoraria, Other: Advisory Board, Speakers Bureau; Janssen: Honoraria, Other: Advisory board, Speakers Bureau; Amgen: Honoraria, Other: Advisory board, Speakers Bureau; BMS: Honoraria, Other: Advisory Board, Speakers Bureau; Celgene Corporation: Honoraria, Other: Advisory board, Speakers Bureau. Tacchetti:BMS: Honoraria; Takeda: Honoraria, Speakers Bureau; Janssen: Honoraria; Oncopeptides: Honoraria, Speakers Bureau; Amgen: Honoraria, Speakers Bureau; Celgene: Honoraria, Speakers Bureau. Mancuso:Celgene: Honoraria, Speakers Bureau; Janssen: Honoraria; Takeda: Honoraria; Amgen: Honoraria. Petrucci:Janssen-Cilag: Honoraria, Membership on an entity's Board of Directors or advisory committees; Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees; Bristol-Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees; Sanofi: Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees. Liberati:Incyte: Consultancy; Servier: Honoraria, Membership on an entity's Board of Directors or advisory committees; AbbVie: Honoraria, Membership on an entity's Board of Directors or advisory committees; Takeda: Membership on an entity's Board of Directors or advisory committees; Amgen: Membership on an entity's Board of Directors or advisory committees; Bristol & Mayer: Honoraria; Janssen: Honoraria; Celgene: Honoraria. Rossi:Roche: Membership on an entity's Board of Directors or advisory committees; Janssen: Membership on an entity's Board of Directors or advisory committees; Daiichi-Sankyo: Consultancy; Celgene: Membership on an entity's Board of Directors or advisory committees; Amgen: Membership on an entity's Board of Directors or advisory committees; Gilead: Membership on an entity's Board of Directors or advisory committees; Sanofi: Membership on an entity's Board of Directors or advisory committees; Abbvie: Membership on an entity's Board of Directors or advisory committees; Pfizer: Membership on an entity's Board of Directors or advisory committees; Jazz: Membership on an entity's Board of Directors or advisory committees; Astellas: Membership on an entity's Board of Directors or advisory committees; Novartis: Honoraria; Mundipharma: Honoraria; BMS: Honoraria; Sandoz: Honoraria. Boccadoro:Bristol-Myers Squibb: Honoraria, Research Funding; Mundipharma: Research Funding; Sanofi: Honoraria, Research Funding; Celgene: Honoraria, Research Funding; Amgen: Honoraria, Research Funding; Janssen: Honoraria, Research Funding; Novartis: Honoraria, Research Funding; AbbVie: Honoraria. Cavo:amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; novartis: Honoraria; sanofi: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; bms: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: travel accommodations, Speakers Bureau; celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: travel accommodations, Speakers Bureau; AbbVie: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees.

Description: Smoldering multiple myeloma (SMM) is an asymptomatic plasma cell disorder whose risk of progression to symptomatic MM (MM) is highly variable. Therefore, the identification of predictors of progression into MM is a relevant end point. Several markers (serum M protein, percentage of bone marrow plasma cells, free light chain, FLC, ratio, immunophenotyping of aberrant plasma cells and focal lesions, FLs at MRI) have already been established to identify sub-groups of SMM patients (pts) with a highest risk of progression into MM. Among imaging methods, FDG-PET/CT is a reliable technique for assessing early skeletal involvement and for predicting outcomes at the onset of MM. However, no data are available regarding the impact of PET/CT FLs in SMM on time to progression (TTP) into symptomatic disease. To address this issue, we prospectively studied pts with a suspected diagnosis of SMM with FDG-PET/CT. A cohort of 73 pts, with a median age of 61 years old (range 27-83) and a confirmed diagnosis of SMM, followed for a median of 2.2 years, is herein reported. By study design, all the pts were studied with PET/CT at baseline. Bone marrow involvement was described as negative, diffuse or focal. The number of FLs, as well as size and associated standardized uptake values (SUV) were recorded. For each FL, the presence of eventual underlying osteolytic lesion was investigated by the CT part of the scan; pts with osteolytic lesions were excluded from the present study, as they were considered as having symptomatic MM. Follow-up took place every 3-4 months and included clinical history, serum and urine markers and PET/CT plus axial MRI for occurrence of symptoms or an increase in M component. Progression to MM was defined by the presence of CRAB features. Skeletal progression was defined by the appearance of one or more sites of osteolytic bone destruction, pathological fractures and/or soft masses at PET/CT or MRI. The start of systemic therapy was defined as the date of event for the analysis of TTP. Baseline patient characteristics were as follows: 83% had IgG isotype, 8% IgA and 9% BJ, with a median M component of 2.5 g/dL; 70% had ISS stage I, 23% stage II and 7% stage III. Median plasma cell involvement on bone marrow (BMPC) was 30% (range 5-100%), with 16% of the pts having more than 60% BMPC. The median serum involved/uninvolved FLC ratio was 14.39 (range 1.28-2255), with 11% of the pts presenting with a ratio ≥ 100. PET/CT was negative in 64/73 pts (88%) and positive in 9/73 (12%) of them; 5 pts had 1 FLs, 1 pt 2 FLs, 2 pts more than 3 FLs and 1 pt a diffuse bone marrow involvement. Median SUV max value was 4.45 (range 2.5-5.2). No significant differences between patients with positive or negative PET/CT were found regarding the other baseline characteristics. At the time of the present analysis, 63% of the pts remained in the asymptomatic phase while 37% of them progressed to MM, in a median time of 4 years, including 21% with skeleton involvement, with/without the appearance of other CRAB symptoms, and 16% with exclusive serological signs of progression. Sixty six per cent of the pts with positive PET/CT progressed to MM in comparison to 33% of the pts with negative PET/CT (P = 0.034). The relative risk of progression of the pts with a positive PET/CT was 2.3 (95% CI 09.-5.9, P= 0.06). Moreover, the relative risk of skeletal progression was 4.0 (95% CI 1.3-12, P= 0.013), with a median TTP of 2.2 years for pts with positive PET/CT versus 7 years for those with negative PET/CT (figure 1). The probability of progression within 2 and 3 years for pts with positive PET/CT was 48% and 65%, respectively, in comparison to 32% and 42% for negative pts. In conclusion, approximately 10% of the pts with SMM have a positive PET/CT, mainly with few FLs, without underlying osteolytic lesion, with a low FDG uptake. PET/CT positivity significantly increased the risk of progression of SMM into active MM. PET/CT could become a new risk factor to define high risk SMM. A larger cohort of pts will be presented at the meeting. Further studies are warranted to find and optimal cut off point of FLs to capture the higher risk of progression at 2 year and to merge with other prognostic factors. Figure 1 Figure 1. Disclosures No relevant conflicts of interest to declare.

Description: F-18-fluorodeoxyglucose positron emission tomography integrated with computed tomography (FDG-PET/CT) enables to detect with relatively high sensitivity and specificity myeloma bone disease and extramedullary sites of metabolically active clonal plasma cells. FDG-PET/CT has also been used to assess and monitor the metabolic response to therapy and to predict the prognosis. One of the major limitation of PET/CT is the lack of standardized image criteria and of inter-observer reproducibility in interpreting the results. Aim of the present sub-study was to prospectively evaluate FDG-PET/CT at diagnosis, after 4 cycles of induction therapy and prior to maintenance therapy in a sub-group of patients enrolled into EMN02/HO95 MM international phase III trial. In particular, the two primary end-points were firstly to assess the prognostic significance of PET/CT at diagnosis and after therapy and secondly to standardize PET/CT evaluation by centralized imaging and revision and definition of criteria for interpretation. Seven hundred and 18 patients with newly diagnosed transplant-eligible symptomatic MM have been prospectively randomized in Italy from February 2011 through April 2014 to receive 4 cycles of bortezomib-melphalan-prednisone (VMP) vs high-dose melphalan and single or double autologous stem cell transplantation (ASCT) as intensification following induction with bortezomib-cyclophosphamide-dexamethasone (VCD). Consolidation therapy with bortezomib-lenalidomide-dexamethasone vs no consolidation was planned after VMP or ASCT(s), followed by lenalidomide maintenance until progression or toxicity. One hundred and three patients were included in the PET/CT imaging sub-study, and followed for a median of 24 months. By study design, PET/CT was performed and analysed in each of the 8 participating centres at baseline, after induction therapy and prior to the start of maintenance (EOT). Each PET scan was a posteriori re-interpreted in a blinded independent central review process, managed by WIDEN®, by a panel of 5 expert nuclear medicine physicians. They described the following characteristics: bone marrow metabolic state (BM), number (Fx) and score (Fs) of focal PET positive lesions, osteolysis (Lx), presence and site of extramedullary disease (EM), and fractures(Fr), according to the IMPeTUs criteria (Nanni et al, EJNM 2015). Moreover, a global score (GS), from 1 to 5, was given to each patient, considering the highest score among BM, Fx, Fs and EM. Concordance among reviewers on different metrics was calculated using Krippendorf's alpha (AK) coefficient Baseline characteristics of the patients were the following: median age 58 years, ISS and R-ISS stage III 15% and 10%, high-risk cytogenetics (t(4;14) ± del(17p) ±del (1p)±1q gain detected by FISH) 42%. At baseline, 78% of the patients had FLs, with a median SUVmax of 6.0. The percentages of PET positive patients for the different characteristics are summarized in table 1. The agreement among reviewer was good for BM (AK=0.49), Fx (AK=0.65), Fs (AK=0.62), Lx (AK=0.62) and EM (AK=0.40). Of all parameters, only Fx ≥ 4 was associated with worse PFS and OS (P = 0.06) Following 4 cycles of VCD, PET/CT remained positive in 59% of the patients, with a median SUVmax of 3.7. Of all parameters, only Fs ≥ 4 was predictive of worse OS (P= 0.05). Prior to maintenance therapy, PET/CT remained positive in 34% of the patients, with a median SUVmax of 3.4. Normal PET/CT findings before maintenance (66%) were associated with a significant improvement in PFS, in particular the following: presence of FLs (P=0.03), Fx ≥ 4 (P=0.001), Fs ≥2 (P=0.03), 3 (P=0.03) and 4 (P=0.006) and SUVmax ≥ 3.4 (p=0.002). GS was also predictive for PFS if ≥ 3 (P=0.033), 4 (P=0.0001) and 5 (P=0.004). The same parameters were also predictive for OS. The prognostic relevance of pre-maintenance PET/CT was retained across the randomization arm (VMP or ASCT), in terms of PFS and OS. In conclusion, PET/CT was confirmed to be a reliable predictor of outcome in newly diagnosed transplant eligible MM patients, whatever the treatment. Normalization of PET/CT before maintenance was associated with a significant improvement for PFS and OS. FDG-PET/CT is by now the preferred imaging technique for evaluating and monitoring response to therapy. Acknowledgments: this study was partially supported by a grant to Elena Zamagni from Fondazione del Monte di Bologna e Ravenna Table 1 Table 1. Disclosures Gay: Amgen: Honoraria; Bristol-Myers Squibb: Honoraria; Celgene: Honoraria; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees; Janssen: Membership on an entity's Board of Directors or advisory committees; Mundipharma: Membership on an entity's Board of Directors or advisory committees. Larocca:Bristol-Myers Squibb: Honoraria; Janssen-Cilag: Honoraria; Celgene: Honoraria; Amgen: Honoraria. Sonneveld:Celgene: Other: Advisory board, Research Funding; Onyx: Other: Advisory board, Research Funding; Millennium: Other: Advisory board, Research Funding; Janssen-Cilag: Other: Advisory board, Research Funding. Cavo:Amgen: Honoraria; Celgene: Honoraria, Research Funding; Janssen: Honoraria, Research Funding; Takeda: Honoraria; Bristol-Myers Squibb: Honoraria.