Citations

Abstract Background: Previous studies have proposed combination of various factors that predict poor mobilization after GCSF stimulation. However, there is no single clinical or laboratory test that reliably correlates with bone marrow reserve and PBPC mobilization. Peripheral blood CD34+ cell count (pCD34) reliably correlates with PBPC mobilization and yield but only after GCSF administration. Methods: We have prospectively followed 36 autologous PBPC transplant candidates, from the time of initial evaluation to transplant, to evaluate factors the correlate with bone marrow reserve and autologous PBPC mobilization. Results: The patients median age was 63 (range 26 – 76). 21 of the 36 patients were diagnosed with dysproteinemia, primarily multiple myeloma, 10 patients had non-Hodgkin’s lymphoma while the remaining 5 had other form of hematological malignancies. Our evaluation shows baseline platelet count prior to growth factor administration significantly correlate with total CD34+ cell yield (spearman: r = 0.64, p <0.001, Figure 1). In addition, daily platelet count during PBPC harvest correlate with CD34+ cell yield for the day (spearman: r = 0.6, p <0.001). Using multiple linear regression model (F = 19.1, p <0.001, R2 = 0.64), we have determined patients’ age (p = 0.03) and type of disease (p <0.001), in addition to platelet count (p<0.001), significantly correlate with total CD34+ cell yield. Further analysis showed low baseline platelet count predicts poor PBPC mobilization. Using Receiver Operating Curve (ROC), we have determined that platelet count of 174,000/ul was the best cut-off for collecting at least 2 million/Kg CD34+ cells with sensitivity of 81% and specificity of 78% and estimated correct classification of 81%. Even though pCD34 counts were slightly more sensitive and were better at identifying poor mobilizers in our cohort (best cut-off 10/ul, sensitivity 96%, specificity 67%, correct classification 89%), their clinical utility were diminished since the values were only known after GCSF administration. Conclusion: Baseline platelet count is a sensitive predictor of bone marrow reserve and can be used prior to growth factor administration to predict poor mobilization. Figure 1: Correlation of baseline platelet count and total CD34+ cell yield Figure 1:. Correlation of baseline platelet count and total CD34+ cell yield

2015 Background: A prior study of intra-CSF topotecan (TOPO) for unselected pts w/ NM reported PFS 6 mo of 19%, and OS of 15 wks (Groves, NeuroOncol 2008;10:208). We postulated that greater activity might occur in pts w/ malignancies considered sensitive to topoisomerase inhibitors. Methods: We reviewed outcome of women with NM and adenocarcinoma of the breast, ovary or lung receiving IVe TOPO (0.4 mg 2x/wk x 4wk, Q wk x 4, Q 2wk x 2, Q mo x 3, Q 2mo x 3, and Q 3mo x 4) until progression (PROG) or adverse events (AE). All had baseline CSF cytology, and MRI of brain and spine. CSF cytology was obtained at each treatment (Rx), and brain/spine MRI Q 3mo. Neuro-specific PROG was defined as recurrent + CSF cytology; PROG of NM on MRI; all-cause neurologic worsening; pt refusal; or death. PFS/OS were measured from 1st TOPO Rx. All pts signed consent; the study was IRB approved. Results: 17 women (breast -12; lung-3; ovary - 2) were treated via Ommaya reservoirs; 7 (41%) had VP shunts w/ valves, adjusted for Rx. Median (med) age was 53 (41-79), and KPS 70 (50-90). At presentation, 11(65%) had + CSF cytology and 14 (82%) had NM on MRI [brain-11 (65%); spine-10 (59%)]. 15 (88%) had no prior intrathecal Rx. 13 pts (76%) received focal RT for CNS disease, and 8 (47%), chemotherapy for extracranial disease. Med.number of Rx were 13/pt (range, 3-50); med. duration of TOPO Rx was 14 wks (range, 1-109). Med. neuro-specific PFS was 13 wks; PFS6 was 41%, and PFS12, 29 %. Med. OS was 33 wks (range, 5-180), w/ 4 alive at 13+, 30+, 33+, and 180+ wks. 4 pts (24%) lived > 95 wks. Of 11 w/ baseline + CSF cytology, 7 (64%) cleared CSF of malignant cells (med. duration clear = 47 wk (range, 9-104). AE included arachnoiditis (18%), leukoencephalopathy (18%), and Ommaya infections (12%). Rx was stopped for neuro PROG (29%); systemic PROG (23%); refusal (18%); AE (12%); or persistent negative CSF (6%); 12% are still on Rx. Conclusions: Promising activity of IVe TOPO was observed in women with NM from breast, lung and ovarian cancer. PFS 6 and 12, OS and cytologic response were twice that noted in prior studies of NM pts w/ unselected malignancies. This data supports our plan for a phase II study targeting this select cohort.

14034 Background: While orthostatic liver transplant (OLT) is an accepted treatment for localized hepatocellular carcinoma (HCC), little data exists as to the appropriate treatment of recurrent disease. Consensus opinion favors avoiding systemic chemotherapy on the grounds that toxicity would be poorly tolerated by patients medically immunosuppressed to prevent allograft rejection. Methods: Study design: retrospective chart review. The medical records of all patients who underwent OLT at the Mayo Clinic in Jacksonville, Florida, from February 1998 to April 2005 were reviewed. Those patients who developed recurrent HCC treated with systemic chemotherapy and were followed for at least 5 weeks with documented side effects were identified as the study population. Tolerance of treatment was assessed through review of side effects and Eastern Co-operative Oncology Group (ECOG) performance status scores. Disease progression was identified as increasing size of lesions on computed tomography (CT) scans and increasing serum alpha fetoprotein (AFP) levels. The primary endpoint was defined as discontinuation of chemotherapy due to severe side effects. Results: Of 1133 patients undergoing OLT, 179 were diagnosed with HCC. Thirty developed recurrent disease. Of these, 8 did not receive chemotherapy (2 observation only, 2 Hospice care, 2 radiation therapy, 1 surgical resection, 1 chemoembolization), 10 were lost to follow-up, and 2 died of rapidly progressive disease. The remaining 10 patients underwent systemic chemotherapy with six patients receiving multiple regimens. Seven patients received from 2 to 15 cycles of gemcitabine and cisplatin. Cytopenias were the most common side effect. One patient discontinued the regimen after developing neutropenic fever following 2 cycles of treatment. Five patients received from 1 to 12 cycles of capecitabine. Diarrhea was the most common side effect. Three patients received from 3 to 6 cycles of doxorubicin. Stomatitis and cytopenias were the most common side effects. No treatment related mortalities were observed. Conclusions: Palliative systemic chemotherapy is not usually associated with life threatening side effects and therefore is a viable option for patients with recurrent HCC following OLT. No significant financial relationships to disclose.

749 Background: Solid Pseudopapillary Neoplasms (SPNs) of the pancreas are rare accounting for 1-2% of all pancreatic tumors. Previous studies had shown that a pathogenic mutation of the CTNNB1 gene is present in over 90% of the SPN tumors with very limited information available on the specific molecular changes present in SPN. Here we report the results of next generation genetic testing of a large series of SPN tumors from the Foundation Medicine database. Methods: Foundation Medicine database from 07/2012 to 04/2019 was reviewed. A total of 31 cases of SPN tumors were identified out of 12,892 cases of pancreatic cancers. Information collected included demographic information on the patients as well as tumor analysis for next generation genetic sequencing of 315 genes associated with cancer with FoundationOne or 324 genes associated with FoundationOneCDx. Microsatellite stability status and tumor mutation burden were determined. Results: Twenty nine out of 31 cases (93%) had a CTNNB1 mutation. Seventy percent of the CTNNB1 mutations were on position 32 (14 cases, 41%) or in position 37 (9 cases, 29%). Other sites of CTNNB1 mutations included position 34 (3 cases, 9.6%), position 2 (2 cases, 6.4%) and position 38 (1 case, 3.2%). Two cases did not have a CTNNB1 mutation, one had a CDKN2A mutation and the other had no detectable mutations. Most cases had additional mutations aside from the CTNNB1, the most common were TP53 (3 cases, 9.6%) and LRP1B (2 cases, 6.4%). Other accompanying mutations were seen just once. Twenty-five percent of these cases had actionable gene mutations, each found in one case including: MSH2, BRCA2, ATM, XRCC3, ATRX, PTEN, ESR1, CDKN2, and PIK3CA. Conclusions: Next generation genetic testing of SPN tumors is of clinical benefit since it identifies actionable mutations in 29% of the cases.

Abstract Background: Disparities in MM survival among different racial groups persist despite improvements in overall survival (OS). We report a comprehensive review of the SEER Medicare database to elucidate the causes of differences in disease presentation, management practices, cost of care and their relationships to outcomes among the MM patients (pts) from different racial groups. Methods: Pts diagnosed with MM between 1991-2010 with continuous Medicare coverage (1 year prior to diagnosis-date of death/end of 2012) were included. MM complications (MM-C); hypercalcemia (C), renal dysfunction (R), anemia (An), bone fractures (B), dialysis (D) occurring prior to/within 30 days of MM diagnosis (at diagnosis; AT-D), or any time later (after diagnosis; AF-D) were summarized. Demographics, survival (PEDSAF files) and disease characteristics, drug/stem cell transplant (SCT) utilization (NCH, OUTSAF, PDESAF files) were obtained. Trends in incidence of MM-C, treatment type over time (proportional odds) and their association with race (logistic regressions) were compared. Associations between race, MM-C AT-D and MM related death using Fine and Gray's competing risk methods were analyzed. Medicare claims adjusted for inflation (2013) within the first 6 months (mth)/total MM care were summed by drug and total charges. Median cost of care by race and year of diagnosis were evaluated by Kruskal-Wallis (univariate) and proportional odds models (multivariate). Results: A total of 35842 pts (52.1% males) with median age of 76 yr (range 18-104) were included. Mutually exclusive racial subgroups were: White (W, 72%), Hispanic (H: 7.3%), African-American (AA, 16.2%), Asian (A, 4.1%), other (0.3%). A significantly increasing trend in the prevalence of all MM-C AT-D was seen over time (all p<0.001). For AF-D, all MM-C initially increased but decreased from 2006-2010 except D that showed continued increase (Fig 1A). For race, MM-C were significantly different, with AA having the most C, R, An and D while W having the most B (Fig 1B). Inferior OS was seen with male gender (p=0.006), increasing age, earlier years of diagnosis, belonging to W or H race, C, R and B (all p<0.001), but not with An (p=0.298) or D (p=0.378). Trends in OS over time showed a significant interaction with race in 1991-1995 (p<0.001), 1996-2000 (p=0.004) and 2001-2005 (p<0.001) but not in 2006-2010 (p=0.182), possibly due to shorter follow up. Medicare claims analysis showed that pts receiving any treatment increased from 12.8% in 1991-1995 to 59.3% in 2006-2010 (p<0.001). Specific therapy utilization, including SCT and all drug classes/agents evaluated increased except for cytotoxic chemotherapy utilization (melphalan/cyclophosphamide), which decreased (Fig 2A). Any therapy utilization was significantly different by race (p<0.001) with highest for H (36.5%) and lowest for AA (31.6%). Specific treatments differed significantly by race (Fig 2B). Cost of care analysis showed significant increase over years for median drug claims (0.23k to 3.63k) and total claims (5.11k to 27.8k) during first 6 mth as well as for any time after MM diagnosis (drug: 1.3k to 9.9k, total: 21.9k to 84k) (p<0.001 for all). Median drug claims in first 6 mth were highest among AA (1.3k) and lowest among A (0.63k) (p<0.001). Same was true for total claims in first 6 mth (p<0.001). For any time after diagnosis, H had the highest drug (p<0.001) and total (p=0.081) claims. There were significant interactions between year of diagnosis, race and cost of care with H seeing the highest increase in drug claims in first 6 mth (p<0.001) and any time (p=0.002). Conclusion: MM-C have generally decreased AF-D due to improved therapeutics although AA continue to have the highest rates of MM-C. Our data shows that utilization and cost of MM care have increased tremendously with resulting improved outcomes, but significant racial disparities persist. These disparities may be in part due to impaired access to new agents from lack of supplemental insurance for certain racial groups. Drug utilization and cost of care disparities may also be due to differences in co-morbidities, MM-C or access leading to differential healthcare utilization and should be explored in order to ameliorate disparities in outcomes. Disclosures Ailawadhi: Pharmacyclics: Consultancy; Novartis: Consultancy; Amgen Inc: Consultancy; Takeda Oncology: Consultancy.

Abstract Background: As of 2013, approximately 558,340 people are living with non-Hodgkin lymphoma (NHL). Outcome disparities have been reported in lymphoid malignancies but a comprehensive analysis, especially with expanding ethnic minorities is necessary. We undertook a large Surveillance Epidemiology and End Results (SEER) based analysis to describe outcome disparities in different subgroups of T-cell and B-cell NHL patients (pts), with a focus on various ethnicities. Methods: The SEER 18 Registry data (1973-2011) was utilized for pts with a confirmed diagnosis of T-cell or B-cell NHL. Cases that received a diagnosis at death certificate or autopsy, no follow-up records, no documented age at diagnosis, sex, or race/ethnicity were excluded. Cox proportional hazards models, adjusted for gender, age, race, year (yr) of diagnosis, and stratified by SEER registries were used to evaluate association between pt characteristics and survival. All statistical tests were two-sided and utilized the SAS software (v9.4) with a two-sided significance level of 0.05. Results: The final analysis included 7,662 pts with T-cell NHL and 84,910 pts with B-cell NHL. The pt demographics are shown in Table 1. Pts were stratified based on yr of diagnosis to study the impact of therapeutic developments on pt outcomes (Table 1). Pts were also divided by T-cell NHL subtype: mature T-cell (9702/3) 51%, angioimmunoblastic T-cell (9705/3) 16%, anaplastic large cell (ALCL) (9714/3) 32%, and hepatosplenic gamma-delta cell (HSϒd) (9716/3) 0.8%. Median age at diagnosis was youngest for AA pts (54 yrs) and oldest for Asian pts (65 yrs) (Figure 1 A). Survival analysis revealed that females had a better median OS than males (3.3 yrs vs. 2.3 yrs, HR 0.876; 95% CI 0.824, 0.932; p<0.001). Increasing age was an independent predictor of worse overall survival, with pts age 18-44 having a median OS 9.4 yrs (HR 0.345; 95% CI 0.312, 0.382) and pts age ≥75 having a median OS of 1.0 yr (p<0.001). There was no statistically significant difference seen in median OS for pts with respect to yr of diagnosis (p=0.081). Among the different T-cell NHL subtypes, pts with ALCL had the best (3.8 yrs, HR 0.766; 95% CI 0.714, 0.822) and pts with HSϒd had the worst median OS (0.7 yrs HR 1.959; 95% CI 1.424, 2.695) (p<0.001). AA pts (1.7 yrs, HR 1.292; 95% CI 1.176, 1.419) and Hispanic pts (1.9 yrs, HR 1.215; 95% CI 1.087, 1.357) had significantly worse OS compared to White pts who had the longest median OS (3.1 yrs) (p<0.001) (Figure 1 B). To compare and contrast with aggressive B-cell NHL, similar analyses were performed using diffuse large B-cell (DLBCL) NHL (9680/3). DLBCL showed similar trends regarding sex, age and race. Ethnic minorities had significantly worse median OS including Hispanic (2.8 yrs, HR 1.154; 95% CI 1.111, 1.198) and AA pts (3.3 yrs, HR 1.261; 95% CI 1.212, 1.312) compared to White pts with a median OS of 5.8 yrs (p<0.001). B-cell NHL pts had a significant improvement in median OS over time with pts diagnosed in 2007-2011 having more than 3 times the median OS of pts diagnosed in 1973-1991 (7 yrs vs. 2.4 yrs; p<0.001). Conclusions: Studies of outcome disparities are important for evaluating disease characteristics and their relationship to specific pt populations over time. We have performed the largest population-based analysis for T-cell and B-cell NHL including various ethnicities in the novel therapeutic agent era. We observed that males, older pts and ethnic minorities had worse median OS for both T-cell and B-cell NHL. Despite novel therapeutics targeting T cells there has been no statistically significant improvement in OS over time. In contrast, significant improvement in B-cell NHL OS has been noted, presumably due to the advent of monoclonal antibodies. These results underline the urgency for the development of novel therapeutics as well as aggressive studies of disease biology and healthcare utilization for better triage of healthcare resources, especially for ethnic minorities. Table 1. Table 1. Figure 1 Figure 1. Disclosures No relevant conflicts of interest to declare.

Introduction: Despite advances in treatment strategy, multiple myeloma (MM) remains a challenging, incurable disease as patients (pts) often relapse. Here we describe preclinical data of a novel cereblon (CRBN) E3 ligase modulatory compound (CELMoD), iberdomide (IBER; CC-220), as well as clinical and translational data from a current phase 1/2 clinical trial (NCT02773030). These data support a differentiated profile for IBER from immunomodulatory agents (IMiD agents), and development of IBER as a foundation of combination therapy for the treatment of relapsed/refractory MM (RRMM). Methods: Preclinical analyses were performed on pomalidomide (POM)-sensitive and acquired-resistant MM cell lines and peripheral blood mononuclear cells from healthy volunteers. Eligible pts enrolled on the clinical trial had RRMM and had received ≥ 2 prior regimens, containing at least an IMiD agent and proteasome inhibitor (PI), and had experienced disease progression within 60 days of last MM therapy. Escalating doses of IBER were given on Days 1-21, in combination with dexamethasone (DEX; 40 mg; 20 mg in pts aged > 75 years) on Days 1, 8, 15, and 22, of each 28-day cycle. Immunohistochemistry (IHC) data on CRBN, Ikaros, Aiolos, and ZFP91 expression was obtained from pt bone marrow specimens at screening and at Cycle 2, Day 15. Immune profiling was evaluated by flow cytometry of peripheral blood at Cycle 1, Day 1 and Cycle 2, Day 15. Primary objectives were to evaluate maximum tolerated dose (MTD), recommended phase 2 dose (RP2D), safety, and preliminary efficacy. Results: Preclinically, IBER exhibited potent tumoricidal anti-MM and immunostimulatory activity. IBER was more potent than lenalidomide (LEN) or POM in overcoming the immunosuppressive activity of bortezomib (BORT), inducing a more than twofold increase in T cell proliferation in the presence of BORT. IBER also enhanced the antibody-dependent cell-mediated cytotoxicity and complement-dependent cytotoxicity of daratumumab (DARA), leading to deeper responses than combinations with LEN or POM. Further differentiating from both LEN and POM, IBER showed activity alone and in combination with BORT or DARA in POM-resistant MM cell lines. As of June 28, 2019, 69 pts with RRMM had received IBER + DEX. Median age was 65 years (range 33-80), and median number of prior regimens was 5 (range 2-12). Prior therapies included autologous stem cell transplantation (80%), LEN (100%), POM (70%), PIs (100%), DARA (71%) and anti-BCMA (6%), including CAR T cells. Clinical activity was observed across all dose levels with an overall response rate (ORR) of 29%, clinical benefit rate of 45%, and disease control rate of 80%. ORR was 30%, 28% and 29% in IMiD agent-refractory, DARA-refractory and Quad-class (IMiD agents/PIs/steroids/CD-38 antibodies)-refractory pts, respectively. IBER + DEX showed a favorable safety profile, with grade 3-4 neutropenia, infections, and thrombocytopenia, occurring in 29%, 25%, and 12% of pts, respectively. To date, IBER doses range from 0.3 to 1.3 mg and the MTD/RP2D has not yet been reached. Pharmacodynamic immunophenotyping changes were dose-dependent. Treatment with IBER (at doses > 0.75mg) + DEX doubled the percentage of proliferating T cells and NK cells (P < 0.001 for each) and increased activated and effector memory CD8+ and CD4+ T cells by > 50% (P < 0.01 for each subset). Pharmacodynamic changes in pt bone marrow by quantitative IHC scoring showed significant degradation of substrates (Ikaros, P = 0.006; Aiolos, P < 0.001; ZFP91, P < 0.001) and downregulation of c-myc (P = 0.027), including in pts refractory to POM and with low CRBN expression. Conclusions: IBER + DEX has shown notable clinical activity and favorable tolerability in heavily pretreated pts with RRMM, including pts refractory to prior IMiD therapy. Preclinical and translational data suggest a differentiated profile of IBER from IMiD agents in regard to activity in POM-resistant models, potency in combination with BORT and DARA, and by inducing changes in CD4+ T cells that were not observed in pts treated with POM from prior studies. Taken together, these data support a differentiated profile for IBER from IMiD agents, and the clinical development of IBER as a foundation of combination therapy for the treatment of RRMM. This study is ongoing, and includes cohorts evaluating the combinations of IBER + DEX with DARA, BORT, and carfilzomib. Updated results will be presented at the meeting. Disclosures Lonial: Karyopharm: Consultancy; GSK: Consultancy; Takeda: Consultancy, Research Funding; Celgene Corporation: Consultancy, Research Funding; Amgen: Consultancy; Genentech: Consultancy; Janssen: Consultancy, Research Funding; BMS: Consultancy. Amatangelo:Celgene Corporation: Employment, Equity Ownership. Popat:Celgene Corporation: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: travel, accommodations, expenses; AbbVie: Consultancy, Membership on an entity's Board of Directors or advisory committees; GSK: Consultancy, Honoraria; Takeda: Honoraria, Other: travel, accommodations, expenses; Janssen: Honoraria, Other: travel support to meetings. Minnema:Gilead: Honoraria; Celgene Corporation: Honoraria, Research Funding; Amgen: Honoraria; Servier: Honoraria; Jansen Cilag: Honoraria. Zonder:Alnylam: Consultancy, Membership on an entity's Board of Directors or advisory committees; BMS: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Consultancy, Membership on an entity's Board of Directors or advisory committees; Oncopeptides: Consultancy, Membership on an entity's Board of Directors or advisory committees; Takeda: Membership on an entity's Board of Directors or advisory committees; Amgen: Consultancy, Membership on an entity's Board of Directors or advisory committees; Intellia: Consultancy, Membership on an entity's Board of Directors or advisory committees; Caelum: Consultancy, Membership on an entity's Board of Directors or advisory committees; Celgene Corporation: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding. Larsen:Janssen Oncology: 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. Oriol Rocafiguera:Celgene Corporation: Consultancy, Speakers Bureau; Janssen: Consultancy; Amgen: Consultancy, Speakers Bureau. Rodriguez Otero:Celgene Corporation: Consultancy, Honoraria, Speakers Bureau; Janssen: Consultancy, Honoraria; Takeda: Consultancy; BMS: Honoraria; Kite Pharma: Consultancy. Badros:Celgene Corporation: Consultancy; Amgen: Consultancy. Siegel:Amgen: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Bristol-Myers Squibb Company: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Janssen: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Takeda: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau. Jagannath:Bristol-Myers Squibb: Consultancy; Janssen Pharmaceuticals: Consultancy; Karyopharm Therapeutics: Consultancy; AbbVie: Consultancy; Merck & Co.: Consultancy; Celgene Corporation: Consultancy. Bringhen:Bristol-Myers Squibb: Honoraria; Celgene Corporation: 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; Janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Karyopharm: Membership on an entity's Board of Directors or advisory committees; Takeda: Consultancy. Gironella:Amgen: Honoraria; Janssen: Honoraria; Celgene Corporation: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Kaiser:Takeda, Janssen, Celgene, Amgen: Honoraria, Other: Travel Expenses; Abbvie, Celgene, Takeda, Janssen, Amgen, Abbvie, Karyopharm: Consultancy; Celgene, Janssen: Research Funding. Cook:Janssen, Takeda, Sanofi, Karyopharm, Celgene: Consultancy, Honoraria, Speakers Bureau; Amgen, Bristol-Myers Squib, GlycoMimetics, Seattle Genetics, Sanofi: Honoraria; Celgene, Janssen-Cilag, Takeda: Honoraria, Research Funding. Gamberi:Janssen: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Sanofi: Consultancy, Membership on an entity's Board of Directors or advisory committees; Amgen: Honoraria; Celgene Corporation: Consultancy, Membership on an entity's Board of Directors or advisory committees. Sonneveld:SkylineDx: Research Funding; Takeda: Honoraria, Research Funding; Karyopharm: Honoraria, Research Funding; Janssen: Honoraria, Research Funding; Celgene: Honoraria, Research Funding; BMS: Honoraria; Amgen: Honoraria, Research Funding. Nguyen:Celgene Corporation: Employment, Equity Ownership. Chen:Celgene Corporation: Employment, Equity Ownership. Homan:Celgene Corporation: Employment. Bjorklund:Celgene Corporation: Employment, Equity Ownership. Wang:Celgene Corporation: Employment, Equity Ownership. Pierceall:Celgene Corporation: Employment, Equity Ownership. Bensmaine:Celgene Corporation: Employment, Equity Ownership. Thakurta:Celgene: Employment, Equity Ownership. Peluso:Celgene Corporation: Employment. Van De Donk:Janssen Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene Corporation: Membership on an entity's Board of Directors or advisory committees, Research Funding; Servier: Membership on an entity's Board of Directors or advisory committees; Bristol-Myers Squibb: Membership on an entity's Board of Directors or advisory committees, Research Funding; Takeda: Membership on an entity's Board of Directors or advisory committees; Roche: Membership on an entity's Board of Directors or advisory committees; AMGEN: Membership on an entity's Board of Directors or advisory committees, Research Funding; Bayer: Membership on an entity's Board of Directors or advisory committees.

PURPOSE Recent trials have shown potential benefit of extended adjuvant endocrine therapy and relatively high risk of recurrence (RoR) after 5 years in hormone receptor-positive (HR+) human epidermal growth factor receptor 2–negative (HER2−) breast cancer. Although risk of late relapse in HR+ HER2− breast cancer is fairly well defined, the risk in HER2-positive (HER2+) breast cancer treated with adjuvant trastuzumab-based chemotherapy remains largely unknown. METHODS We included 3,177 patients with HER2+ breast cancer treated with adjuvant chemotherapy alone or with trastuzumab from the North Central Cancer Treatment Group N9831 (ClinicalTrials.gov identifier: NCT00005970 ) and National Surgical Adjuvant Breast and Bowel Project B-31 (ClinicalTrials.gov identifier: NCT00004067 ) trials. RESULTS Overall, HR+ breast cancer was significantly associated with improved recurrence-free survival (RFS) during the first 5 years (hazard ratio, 0.65; 95% CI, 0.56 to 0.77; P < .001). Among patients treated with trastuzumab, cumulative hazard for RFS was lower in patients with HR+ HER2+ breast cancer during the first 5 years (10.96% v 17.48%; hazard ratio, 0.60; 95% CI, 0.45 to 0.79; P < .001). However, there was no significant difference in RFS based on HR status during years 5 to 10 (hazard ratio, 1.32; 95% CI, 0.93 to 1.88; P = .12). A comparable degree of trastuzumab benefit was observed in HR+ and HR− breast cancers ( P for interaction = .87). Furthermore, we observed low RoR in years 5 to 10 among patients with HR+ HER2+ breast cancer: 3.23% in patients without lymph node involvement (N0) and 6.39% in patients with involvement of one to three lymph nodes (N1). CONCLUSION The benefit of adjuvant trastuzumab persists for a long time. A distinct pattern of recurrence was observed between HR+ and HR− HER2+ disease but with similar degree of benefit from adjuvant trastuzumab. RoR in years 5 to 10 in HR+ HER2+ breast cancer is low, particularly in patients with N0 or N1 disease.

Abstract Background Waldenstršms macroglobulinemia (WM) is a rare and incurable indolent Non-Hodgkin's lymphoplasmacytic lymphoma. Rarity and limited availability of authentic preclinical models has been a major constraint in drug development for WM. We recently reported the establishment and characterization of a novel human WM cell line, RPCI-WM1. Thereafter we evaluated the tumorigenic potential of this unique WM cell line in a xenograft mouse model along with its ability to produce human IgM in vivo. Moreover, we assessed its potential as a possible model for enhanced understanding of WM cell biology in vivo and a mechanism to conduct functional studies and preclinical anti-WM drug evaluation. Aim The primary goal of this experiment was to develop and validate an in vivo WM model that can be used to investigate WM cell biology as well as drug evaluation. Methods The RPCI-WM1 cell line (1x106 cells) was injected both subcutaneously and via tail vein into female SCID mice. Engraftment was validated via detection of human IgM (ELISA) and tumor growth (as well as response to therapy) was monitored by weekly assessment of IgM levels and external tumor formation measurements. Results After subcutaneous injection (flank) into mice, the RPCI-WM1 cells developed localized tumors that secreted human IgM detectable in serum as early as 14 days. Progressive increase in IgM was measured in the serum and this corresponded with tumor growth in a time-dependent fashion. On average, tumor tissues grew to a median of 3 cm and IgM levels reached a median of 823 ng/mL by Day 30 post-implantation. We also assessed the practical utility of this xenograft mouse model for evaluation of therapeutics, using a compound X (propriety drug with demonstrable in vitro anti-WM effects). Eleven days post-implantation, the mice were randomized into 3 groups receiving either DMSO (n=6), 100 mg of compound X (n=7) or 200 mg/kg of compound X (n=7) every alternate day via intraperitoneal injection for 26 days. On Day 37, mice were sacrificed and tumor volume was measured. We observed a 48% reduction in tumor volume in the 100mg/kg cohort, with no additional anti-WM benefit noted in the 200mg/kg cohort. Human IgM secreted by the xenografted tumors was measured by ELISA and was significantly lower in mice treated with compound X versus the control group (Figure 1). We also conducted immunohistochemistry (IHC) analysis on tumor tissues obtained from 9 mice treated with compound X (both dose cohorts) or DMSO alone. IHC staining demonstrated changes in the known target proteins of compound X (such as BCL2, p53, Ki-67) between the treated and untreated mice. Summary Thus we demonstrate that the RPCI-WM1 cell line can be dependably used to induce tumor growth through xenotransplantation in SCID mice and this mimics the IgM secreting clinical disease model. This can then be used to serve as a platform for preclinical testing of novel anti-WM therapeutics and allow for subsequent correlative studies for pharmacodynamics purpose. Comprehensive data regarding this model its utility in evaluation of various biological questions such as those relevant to the tumor microenvironment as well therapeutic modeling will be presented. We are grateful to the Leukemia and Lymphoma Society and the International Waldenstršm Macroglobulinemia Foundation for their continued support. Disclosures: No relevant conflicts of interest to declare.