Search

Purpose: Spleen tyrosine kinase (SYK) signaling is a proposed target in acute myeloid leukemia (AML). Sensitivity to SYK inhibition has been linked to HOXA9 and MEIS1 overexpression in preclinical studies. This trial evaluated the safety and efficacy of entospletinib, a selective inhibitor of SYK, in combination with chemotherapy in untreated AML. Patients and Methods: This was an international multicenter phase Ib/II study, entospletinib dose escalation (standard 3+3 design between 200 and 400 mg twice daily) + 7+3 (cytarabine + daunorubicin) in phase Ib and entospletinib dose expansion (400 mg twice daily) + 7+3 in phase II. Results: Fifty-three patients (n = 12, phase Ib and n = 41, phase II) with previously untreated de novo (n = 39) or secondary (n = 14) AML were enrolled (58% male; median age, 60 years) in this study. The composite complete response with entospletinib + 7+3 was 70%. Patients with baseline HOXA9 and MEIS1 expression higher than the median had improved overall survival compared with patients with below median HOXA9 and MEIS1 expression. Common adverse events were cytopenias, febrile neutropenia, and infection. There were no dose-limiting toxicities. Entospletinib-related skin rash and hyperbilirubinemia were also observed. Conclusions: Entospletinib with intensive chemotherapy was well-tolerated in patients with AML. Improved survival was observed in patients with HOXA9/MEIS1 overexpression, contrasting published data demonstrating poor survival in such patients. A randomized study will be necessary to determine whether entospletinib was a mediator this observation.

Background Some men with biopsy Gleason score (GS) 7 prostate cancer (PC) harbor occult GS 8 to 10 PC and might be undertreated with short-term androgen deprivation therapy (ADT) and radiation therapy (RT). With advancing age associated with occult high-grade PC, we evaluated PC-specific mortality (PCSM) risk after RT and short-term ADT for older men with GS 4+3 PC and men of any age with GS 8 to 10 PC. Patients and Methods The study cohort comprised 206 men with unfavorable-risk PC treated with RT or RT and 6 months of ADT on a randomized trial between 1995 and 2001. Competing risks regression was used to compare PCSM risk for men with GS 8 to 10 PC to men with GS ≤ 3+4, GS 4+3 and age ≤ 73 years (median age), and GS 4+3 and age > 73 years, adjusting for PC risk factors, comorbidity, and treatment. Results After a median follow-up of 14.3 years, 135 men died (65.53%), 24 (17.78%) of PC. Men age > 73 years with GS 4+3 PC did not have significantly lower PCSM risk compared with men with GS 8 to 10 (adjusted hazard ratio [AHR], 1.08; 95% confidence interval [CI], 0.29-4.06; P = .91); whereas unhealthy men (AHR, 0.20; 95% CI, 0.04-0.93; P = .04) and men age ≤ 73 years with GS 4+3 (AHR, 0.09; 95% CI, 0.01-1.03; P = .05) fared better. Conclusion Men age > 73 years with biopsy GS 4+3 did not have a significant difference in PCSM risk than men with GS 8 to 10, supporting further study of multiparametric magnetic resonance imaging in such men with no or minimal comorbidity before determining ADT duration.

Objectives To determine if androgen-deprivation therapy (ADT) is associated with excess cardiac-specific mortality (CSM) in men with prostate cancer and no cardiovascular comorbidity, coronary artery disease risk factors, or congestive heart failure (CHF) or past myocardial infarction (MI). Patients and Methods In all, 5077 men (median age 69.5 years) with cT1c-T3N0M0 prostate cancer were treated with brachytherapy with or without neoadjuvant ADT (median duration 4 months) between 1997 and 2006. Fine and Gray competing risks analysis evaluated the association of ADT with CSM, adjusting for age, year of brachytherapy, and ADT treatment propensity score among men in groups defined by cardiac comorbidity. Results After a median follow-up of 4.8 years, no association was detected between ADT and CSM in men with no cardiac risk factors (1.08% at 5 years for ADT vs 1.27% at 5 years for no ADT, adjusted hazard ratio (AHR) 0.83; 95% confidence interval (CI), 0.39–1.78; P = 0.64; n = 2653) or in men with diabetes mellitus, hypertension, or hypercholesterolaemia (2.09% vs 1.97%, AHR 1.33; 95% CI 0.70–2.53; P = 0.39; n = 2168). However, ADT was associated with significantly increased CSM in men with CHF or MI (AHR 3.28; 95% CI 1.01–10.64; P = 0.048; n = 256). In this subgroup, the 5-year cumulative incidence of CSM was 7.01% (95% CI 2.82–13.82%) for ADT vs 2.01% (95% CI 0.38–6.45%) for no ADT. Conclusion ADT was associated with a 5% absolute excess risk of CSM at 5 years in men with CHF or prior MI, suggesting that administering ADT to 20 men in this potentially vulnerable subgroup could result in one cardiac death.

The addition of androgen deprivation therapy (ADT) to external beam radiotherapy (RT) decreases prostate cancer-specific mortality (PCSM) in patients with intermediate- and high-risk prostate cancer (PCa); however, whether this is true across the spectrum of percent positive biopsy (PPB) values is unknown and was evaluated in the current study. From 1995 to 2001, 206 men with intermediate- or high-risk PCa were randomized to receive RT alone or RT and 6 months of ADT; 149 men with no or minimal comorbidity comprised the study cohort. Fine and Gray competing risk regression was used to ascertain whether an increasing PPB was associated with an increased risk of PCSM adjusting for age, known PCa prognostic factors, and treatment. After a median follow-up of 14.26 years, 88 men died in total (59 %), 20 of prostate cancer (23 %). RT as compared to RT + ADT [adjusted hazard ratio (AHR) 4.12 (1.10, 15.35), p = 0.04] and an increasing PPB [AHR 1.04 (1.02, 1.06), p 14 years with a PPB of

BACKGROUND Recently, men with intermediate-risk prostate cancer (PC) were classified into favorable and unfavorable categories; however, whether the risk of PC-specific mortality (PCSM) among men with high-risk PC versus unfavorable intermediate-risk PC is increased is unknown. METHODS In a prospective, randomized trial conducted between 1995 and 2001, 206 men with intermediate-risk or high-risk PC were randomized to receive 70 Gy with or without 6 months of androgen-suppression therapy (AST). The subgroup of 197 patients with information available on the percentage of positive biopsies formed the cohort. Fine and Gray regression analysis was used to assess whether men with high-risk PC versus unfavorable intermediate-risk PC had an increased risk of PCSM. RESULTS After a median follow-up of 14.3 years, there were 127 deaths (64.5%), including 22 deaths (17.3%) from PC. There were no PC deaths in the favorable intermediate-risk group. There was an increase in the risk of PCSM among men with high-risk PC versus unfavorable intermediate-risk PC, but the difference was not significant (adjusted hazard ratio, 1.59; 95% confidence interval, 0.66-3.83; P = .30) after adjusting for age, randomized treatment arm, and comorbidity. CONCLUSIONS The lack of PC deaths among men with favorable intermediate-risk PC suggests that adding AST may not reduce their risk of PCSM; whereas many men with unfavorable intermediate-risk PC are at risk for harboring occult PC with Gleason scores from 8 to 10 and, if proven, would benefit from long-term AST. Multiparametric magnetic resonance imaging and targeted biopsy of suspicious lesions should be considered to identify PC with Gleason scores from 8 to 10 in these men. Cancer 2014;120:1787–1793. © 2014 American Cancer Society.

Purpose. Increasing body mass index (BMI) is associated with higher risk prostate cancer (PC) at presentation. Whether increasing BMI also prompts earlier salvage androgen suppression therapy (sAST) is unknown.Materials and Methods. Between 1995 and 2001, 206 men with unfavorable risk PC were treated with radiation therapy (RT) or RT and six months of androgen suppression therapy in a randomized controlled trial (RCT). 108 sustained PSA failure; 51 received sAST for PSA approaching 10 ng/mL; 49 with BMI data comprised the study cohort. A multivariable Cox regression analysis identified pretreatment factors associated with earlier sAST receipt.Results. Increasing BMI prompted earlier sAST (median years: 3.7 for overweight/obese, 6.9 for normal weight; adjusted hazard ratio (AHR): 1.11; 95% CI: 1.04, 1.18;P=0.002) as did high versus other risk PC (median: 3.2 versus 5.2 years; AHR: 2.01; 95% CI: 1.05, 3.83;P=0.03). Increasing median time to sAST was observed for overweight/obese men with high versus other risk PC and for normal-weight men with any risk PC being 2.3, 4.6, and 6.9 years, respectively (P<0.001for trend).Conclusion. Increasing BMI was associated with earlier sAST. A RCT evaluating whether BMI reduction delays or eliminates need for sAST is warranted.

Introduction: Targeted therapy for KMT2A (mixed lineage leukemia [MLL]) rearranged acute leukemia (AL) is lacking. KMT2A regulates leukemic stem cell transcription factors HOXA9 and MEIS1. Spleen tyrosine kinase (SYK) signaling induces MEIS1 in conjunction with HOXA9. We hypothesize that this regulatory loop may be sensitive to SYK inhibition with Entospletinib (ENTO) a highly selective, oral SYK inhibitor. In this analysis, we evaluate the efficacy of ENTO in patients with acute myeloid leukemia (AML) and acute lymphoblastic leukemia (ALL) with t(v;11q23.3) KMT2A/MLL gene rearrangements. Methods: Patients with KMT2A rearranged AL in two different clinical trials were included. AML patients (NCT02343939) received ENTO 400mg BID monotherapy for up to 14 days prior to and with induction chemotherapy (cytarabine 100 mg/m2 for 7 days plus daunorubicin 60 mg/m2 for 3 days) if previously untreated, or ENTO monotherapy alone if relapsed/refractory (R/R). R/R B-ALL patients received ENTO monotherapy for 7 days prior to and with vincristine and dexamethasone in a phase 1 study (NCT02404220). Results: 18 patients with KMT2A rearranged AL were treated. Untreated AML (n=10) patients had a median age of 49 years. One patient was in a morphologic leukemia-free state after ENTO monotherapy (before chemotherapy). After induction chemotherapy plus ENTO, seven patients had morphologic (CR) and cytogenetic (CRc) remission, but two of them had incomplete count recovery (CRi). The composite CR rate (CR/CRi/CRc) was 90%: 5 CRc, 3 CRi (CR/CRc with incomplete count recovery), and 1 CR. Six patients underwent allogeneic stem cell transplantation (SCT) in CR1. After median follow-up of 9.9 months one patient who achieved CR relapsed, with persistence of t (6;11) and an NRAS mutation. Median overall survival and event-free survival have not been reached. In R/R AML (n=6), patients had a median age of 48 years, with 2 median prior therapies. One had CR and one had CRi (but normal cytogenetics) and both received SCT. In all, 3 AML patients (1 newly diagnosed, 2 R/R) responded to ENTO monotherapy alone. In R/R ALL (n=2), median age was 59 years. Both patients had t (4;11) along with other cytogenetic abnormalities with 2 prior therapies. Both patients achieved CR with loss of KMT2A on cytogenetic testing, and one patient received SCT. Overall, ENTO was safe and well tolerated, even in combination with chemotherapy. Conclusions: KMT2A rearranged AL is sensitive to ENTO with CR observed on monotherapy in AML and high response rates in AL patients treated with combination therapy. This represents the first documentation of CR with small molecule monotherapy (n=3) in this genetic subgroup, which typically portends a poor prognosis. Correlative biomarker studies evaluating HOXA9/MEIS1 in patients with t(v;11q23.3) KMT2A rearranged leukemia treated with ENTO are pending. Citation Format: Alison R. Walker, John C. Byrd, William Blum, Tara Lin, Howland E. Crosswell, Danjie Zhang, Jie Gao, Arati V. Rao, Mark D. Minden, Wendy Stock. High response rates with entospletinib in patients with t(v;11q23.3);KMT2A rearranged acute myeloid leukemia and acute lymphoblastic leukemia [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 819.

Purpose We estimated the risks of prostate cancer–specific mortality (PCSM) and all-cause mortality (ACM) in men with high-risk prostate cancer (PC) undergoing external beam radiation therapy and brachytherapy with short-course androgen deprivation therapy (ADT) (median 4 months) as compared with men with more favorable-risk PC undergoing standard of care as per the National Comprehensive Cancer Network guidelines. Methods and Materials The prospective study cohort comprised 6595 consecutively treated men with T1-4 N0M0 PC whose treatment included brachytherapy between October 16, 1997, and May 28, 2013. Fine and Gray competing risk regression and Cox regression analyses were used to assess the risks of PCSM and ACM in men with high, unfavorable intermediate, and favorable intermediate risk as compared with low-risk PC. Results After median followup of 7.76 years, 820 men died (12.43%): 72 of PC (8.78%). Men with favorable intermediate–risk PC did not have significantly increased PCSM risk as compared with men with low-risk PC (adjusted hazard ratio [AHR], 1.26; 95% confidence interval [CI] 0.56, 2.88; p-Value 0.58), whereas men with high-risk PC (AHR, 3.74; 95% CI 1.12, 12.53; p-Value 0.032) and unfavorable intermediate–risk PC (AHR, 3.10; 95% CI 1.43, 6.72; p-Value 0.004) did. Based on 10-year adjusted point estimates of PCSM and ACM for men with high-risk PC being 6.01% (95% CI 3.79%, 8.94%) and 21.30% (95% CI 17.45%, 25.42%), respectively, PCSM comprised 28% of ACM. Conclusions In the setting of external beam radiation therapy and brachytherapy, men with high-risk PC have low absolute adjusted estimates of PCSM (∼6%) during the first decade after treatment despite receiving only short-course ADT. Whether long-term ADT can lower PCSM and improve survival in these men requires additional study.

Introduction: Entospletinib is an orally bioavailable, selective inhibitor of spleen tyrosine kinase. Targeting the B-cell receptor (BCR) signaling pathway with Bruton's tyrosine kinase (BTK) and PI3Kd inhibitors (BTKi and PI3Kdi), approved for treatment of chronic lymphocytic leukemia (CLL), has been a successful therapeutic strategy. Entospletinib is active in CLL and preclinical data suggest that entospletinib may be effective even in the context of resistance to BTKi, including that conferred by activation of PLCγ2 (Liu et. al. Blood 2015). Methods: This is an ongoing phase 2 trial (NCT01799889) of entospletinib in CLL and non-Hodgkin lymphoma. The study protocol includes 2 CLL cohorts for patients who have been previously treated with BTKi or PI3Kdi and 2 additional cohorts for patients with Richter's transformation who have had analogous prior treatment. Patients were treated with entospletinib monotherapy (400 mg BID) and evaluated using modified Hallek/IWG-CLL criteria every 2 to 3 months as previously described (Sharman et. al. Blood 2014). Results: As of June 28, 2016, 34 patients have been enrolled, and 33 have been treated. Of the 28 patients without Richter's transformation, 23 were previously treated with a BTKi (22 ibrutinib, 1 CC-292) and 5 with a PI3Kdi (idelalisib). Median number of prior treatments was 3 (1-7) for patients with prior BTKi and 5 (3-8) for prior PI3Kdi treatment. In total, 35% of the BTKi patients and 60% of the PI3Kdi patients had either a TP53 mutation or del17p; 75% did not have IgHV hypermutation. A median of 2 months (0-14) had elapsed since the prior treatment; 17 patients had progressive disease on prior therapy, while 11 discontinued prior therapy due to intolerance. Thirteen of the 28 patients enrolled without Richter's transformation remain on study with a median PFS of 5.6 months for the prior BTKi cohort and a median PFS of 6.9 months for the prior PI3Kdi cohort. Of the 15 patients who have stopped therapy, 9 discontinued due to disease progression, 5 discontinued due to an AE, and 1 withdrew consent. Overall, 19 patients were evaluable for response (15 BTKi/4 PI3Kdi; Table 1). Of the 6 patients who achieved a PR, all lacked IgHV hypermutation and 3 had either a TP53 mutation or del17p, and 3 had progressed on prior therapy. Following Richter's transformation, 5 patients have been treated with entospletinib (3 with prior BTKi therapy and 2 with prior PI3Ki). The interval since prior treatment was short ( All patients on study experienced a treatment-emergent AE (TEAE) and 49% experienced a serious AE (SAE; Table 2). Only 1 SAE, pancreatitis, was attributed to entospletinib. The most common TEAEs and laboratory abnormalities are listed in Table 2. Additional Grade ≥3 TEAEs reported in more than 1 patient included sepsis (3), atrial fibrillation (2), dehydration (2), neutropenia (2), pneumonia (2), respiratory failure (2), and urinary tract infection (2). The only TEAE attributable to entospletinib that led to discontinuation of treatment was fatigue. Five patients died on study; 2 from progressive disease and 1 each from heart failure, Guillain-Barre syndrome, and cardiac arrest; 3 of these 5 patients died within 30 days of the last dose of study drug [disease progression (2), cardiac arrest (1)]. Conclusion: Early experience from this trial with ongoing enrollment demonstrates that entospletinib has clinical activity following therapy with either BTKi or PI3Kdi. Continued investigation of treatment with entospletinib following progression after therapy with BCR signaling pathway inhibitors is warranted. Disclosures Sharman: Gilead Sciences, Inc.: Honoraria, Research Funding. Shustov:Celgene: Consultancy, Honoraria; SPECTRUM: Consultancy, Research Funding; Seattle Genetics: Research Funding; Novartis: Research Funding; BMS: Consultancy, Honoraria. Smith:Celgene: Honoraria; Spectrum: Honoraria; Abbvie: Research Funding; Genentech: Honoraria. Kolibaba:Cell Therapeutics: Research Funding; Gilead: Consultancy, Research Funding; Genentech: Research Funding; GSK: Research Funding; Janssen: Research Funding; Acerta: Research Funding; Amgen: Research Funding; Celgene: Research Funding; Novartis: Research Funding; Pharmcyclics: Research Funding; Seattle Genetics: Research Funding; TG Therapeutics: Honoraria, Research Funding. Abella-Dominicis:Gilead Sciences: Employment, Equity Ownership. Zhang:Gilead Sciences: Employment, Equity Ownership. Mitra:Gilead Sciences: Employment, Equity Ownership. Yasenchak:Seattle Genetics: Research Funding. Awan:Pharmacyclics: Consultancy; Innate Pharma: Research Funding; Novartis Oncology: Consultancy.

Introduction: Entospletinib (GS-9973) is an orally bioavailable, selective inhibitor of spleen tyrosine kinase (Syk). Syk is a mediator of B-cell receptor signaling in normal and transformed B-cells. Targeting the B-cell receptor (BCR)-signaling pathway has been the focus in many types of B-cell related hematological malignancies including mantle cell lymphoma (MCL). Methods: This reports the MCL cohort in a phase 2 trial that more broadly evaluated the efficacy and safety of entospletinib (800 mg BID) in patients with relapsed and refractory hematological malignancies (NCT01799889). Tumor response was assessed per Cheson 2007 criteria with imaging planned at weeks 8, 16, 24, and then every 12 weeks. The primary endpoint was PFS at week 16. All efficacy data were assessed by an Independent Review Committee. Results: A cohort of 39 patients with MCL was enrolled. The median age was 72 years (range: 49-92), 64% were male, and a median number of prior regimens were 2 (range: 1-6). Prior therapy included anti-CD20 antibodies (95%), alkylating agents (95%; bendamustine 44%), and anthracyclines (77%). Three patients (8%) have received ibrutinib either as investigational drug (n = 1) or as an approved drug (n = 2), and 1 patient (3%) received idelalisib. Median duration of treatment was 21 weeks (range: 1-87), with 1 patient continuing on treatment. Thirty-five (90%) patients were evaluable for tumor response. Four patients (10%) discontinued prior to initial tumor assessment: death (n = 1), disease progression (n = 2) and investigator's discretion (n = 1). The most common TEAEs (any grade/≥gr 3, independent of causality) and common lab abnormalities are summarized in Table 1. There were 4 TEAEs that led to study drug discontinuation (all n = 1): cardiac arrest, pruritus, pyrexia, and maculopapular rash. Six deaths were reported, none of which were related to study drug. The ORR was 15% (90% CI: 6.9%, 28.1%), with 6 (15%) patients achieving a PR and 23 (59%) patients maintaining a stable disease. The PFS rate at week 16 was 66% (95% CI: 46%, 79%). Median PFS was 5.6 months (95% CI: 3.6 months, 8.9 months). These results are based on data analysis of June 28, 2016. Conclusion: Entospletinib was well tolerated and demonstrated modest activity in patients with relapsed or refractory MCL. Further development of entospletinib in MCL will focus on the development of combination therapy. Figure 1 Waterfall Plot of Best % Change from Baseline in SPD. Figure 1. Waterfall Plot of Best % Change from Baseline in SPD. Figure 2 Kaplan-Meier Curve of Progression-Free Survival. Figure 2. Kaplan-Meier Curve of Progression-Free Survival. Disclosures Sharman: Gilead Sciences, Inc.: Honoraria, Research Funding. Kolibaba:Amgen: Research Funding; Celgene: Research Funding; Cell Therapeutics: Research Funding; Genentech: Research Funding; GSK: Research Funding; Janssen: Research Funding; Acerta: Research Funding; Gilead: Consultancy, Research Funding; Novartis: Research Funding; Pharmcyclics: Research Funding; Seattle Genetics: Research Funding; TG Therapeutics: Honoraria, Research Funding. Shustov:Seattle Genetics: Research Funding; BMS: Consultancy, Honoraria; Celgene: Consultancy, Honoraria; SPECTRUM: Consultancy, Research Funding; Novartis: Research Funding. Nay:Gilead Sciences, Inc.: Honoraria; Janssen: Honoraria, Other: Advisory board; Celgene: Honoraria, Other: Advisory board; Amgen: Other: Advisory board; Lyndbeck: Honoraria; BMS: Honoraria. Zhang:Gilead Sciences: Employment, Equity Ownership. Shi:Gilead Sciences, Inc.: Employment, Equity Ownership. Forero:University of Alabama at Birmingham: Research Funding. Assouline:BMS: Speakers Bureau; Lundbeck: Consultancy; Janssen: Consultancy, Speakers Bureau; Pfizer: Speakers Bureau.

Nicotinamide phosphoribosyltransferase (Nampt), an enzyme involved in the NAD⁺ salvage pathway, is over-expressed and important in the carcinogenesis in several types of cancers. The expression of Nampt and its role in gastric cancer remain largely unknown. In this study, using real-time PCR and Western blotting we found that Nampt was overexpressed at the mRNA and protein levels, respectively, in established gastric cancer cells and human gastric cancer tissues. The specific Nampt inhibitor FK866 repressed gastric cancer cell proliferation, as assessed by MTT assay. Using transwell and soft agar clonogenic assays, we also found that FK866 suppressed gastric cancer cell migration and anchorage-independent growth, respectively. These inhibitory effects of FK866 were accompanied by significantly decreased expression of VEGF, MMP2, MMP9 and NF-κB. As determined by MTT assay and flow cytometry, FK866 also increased the chemo-sensitivity of gastric cancer cells to fluorouracil by greater inhibition of cell proliferation and the induction of apoptosis. Our findings indicate that Nampt may be a new therapeutic target for gastric cancer.

In a recent clinical observation, the growth of endothelial tumors, such as nasopharyngeal carcinoma, was repressed by the non-selective-adrenergic antagonist propranolol. In this study, we evaluated whether β-adrenoceptors (β-ARs), nuclear factor κB (NF-κB), vascular endothelial growth factor (VEGF), cyclooxygenase-2 (COX-2), matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9) were involved in modulating cell apoptosis and cell cycle arrest by propranolol in human gastric adenocarcinoma cell lines (SGC-7901 and BGC-823) in vitro. Our results showed that the propranolol treatment inhibited cell proliferation in a concentration-dependent manner, suggesting the involvement of β-ARs in this cellular response. Propranolol-induced growth inhibition was associated with G0/G1 arrest and G2/M arrest depending upon the concentration. In addition, propranolol also induced apoptosis in both cell lines, as determined by Annexin V staining assay. Furthermore, propranolol decreased the level of NF-κB and then downregulated VEGF, Cox-2, MMP-2 and MMP-9 expression. Collectively, these results suggested that propranolol repressed gastric cancer cell growth through the inhibition of β-ARs and the downstream NF-κB-VEGF/MMP-2/9/COX-2 pathway.

patients received a course of hormone deprivation for 6 months at least. One biochemical relapse was observed in this cohort of patients. Five patients died during the follow-up period without cancer relapse or toxicity. Acute genitourinary toxicity was observed in 81% of patients with maximal score of 2 in 40.9% of patients. Charlson score greater than 4 did not predict an increase in toxicity. Rectal acute toxicity grade 2 with mucosal discharge was present in 17.6% of patients. Presence of any acute rectal toxicity risk was increased by 2.3 fold in the shorter OTT (cut-point 47 days). Late rectal toxicity Grade 3 was seen in 1 patient, and 5 more patients showed a grade 2 score. Chronic urinary toxicity grades 1-2 were observed in 27.5% of patients, but only 2 patients had grade 2 urinary toxicity. Conclusion: IMAT with SIB to the prostate was well tolerated, with acceptable rates of acute and early late toxicity. Shorter OTT seems to increase the risk of acute rectal toxicity. Charlson score should not be considered as a predictor factor for toxicity. Additional follow-up is necessary to fully define the long-term toxicity. Author Disclosure: F. Ferrer: None. G. Mendez: None. C. Chiruzzi: None. H. Letelier: None. A. Boladeras: None. R. De Blas: None. R. Pineiro: None. M. Galdeano: None. D. Najjari: None. E. Zardoya: None. R. Chavez: None. M. Ventura: None. E. Martinez: None. C. Gutierrez: None. C. Picon: None. J. Pera: None. F. Guedea: None.

82 Background: Active surveillance (AS) is considered appropriate for patients with low-risk prostate cancer (PC) and a life expectancy of at least 10 years. However, with grade migration following the 2005 International Society of Urologic Pathology consensus conference, AS may also be an initial option for men with favorable intermediate-risk PC. We estimated and compared the risk of PC-specific mortality (PCSM) following high dose radiation therapy and androgen deprivation therapy as appropriate amongst men with low, favorable intermediate, unfavorable intermediate, and high-risk PC. Methods: The study consisted of 6,595 consecutively treated men (median age: 68 years) with localized or locally advanced PC at the Chicago PC Center between 1997 and 2013. Fine and Gray competing risks regression analyses (table) were used to assess the risk of PCSM in men with favorable intermediate, unfavorable intermediate or high-risk compared to low-risk PC, adjusting for age at and year of treatment. Results: After median follow-up of 7.76 years, 820 men died: 72 of PC. While men with favorable intermediate-risk did not have significantly increased risk of PCSM as compared to low-risk PC (adjusted hazard ratio (HR) 1.28, 0.63-2.62 95% confidence interval (CI), p-value 0.49), men with high (adjusted HR 9.91, 5.48-17.94 95% CI, p-value

27 Background: We assessed the risk of prostate cancer-specific mortality (PCSM) in men with unfavorable and favorable intermediate-risk prostate cancer (PC) who received dose-escalated radiotherapy (RT) with or without short-course androgen deprivation therapy (ADT). Methods: The cohort consisted of 2,668 men with intermediate-risk PC (71.3% favorable, 28.7% unfavorable) who were treated with dose-escalated RT with or without ADT (median 4 mos.) from 1997 - 2013. Fine and Gray's competing risks regression was used to assess whether ADT decreased PCSM-risk in an adjusted multivariable model (Table). An interaction term was included to assess for potential differences in the impact of ADT on PCSM risk in men with favorable versus unfavorable intermediate-risk PC. Results: After a median follow-up of 7.84 years, there were 393 deaths (14.73%), of which 33 were from PC (8.40%). There was significant reduction in PCSM-risk in men with unfavorable intermediate-risk PC who received ADT (AHR 0.39, 95% CI 0.16 to 0.92, P=0.033), but no significant difference in PCSM-risk in men with favorable intermediate-risk PC who received ADT (AHR 0.68, 95% CI 0.19 to 2.49, P=0.561). Conclusions: While ADT reduced PCSM-risk in men with unfavorable intermediate-risk PC, there was no significant improvement in men with favorable intermediate-risk PC, suggesting that for these patients ADT in addition to dose-escalated RT may not be required to minimize PCSM-risk. [Table: see text]

Purpose/Objective(s): Randomized trials that showed superiority of adding androgen deprivation (ADT) to radiation (RT) in terms of survival did not include pre-randomization stratification by percent positive biopsy cores (PPB), a known prostate cancer prognostic factor. The purpose of the current study is to evaluate the impact of adding 6 months of ADT to RTon the risk of prostate cancer-specific mortality (PCSM) stratified by low or high PPB using data from a prospective randomized controlled trial for men in good health with intermediate or high-risk PC. Materials/Methods: From December 1, 1995 to April 15, 2001, 206 men with localized but intermediate or high-risk PC were randomized to receive either RT alone or in combination with 6 months of ADT. A subgroup of the 149 men with no or minimal comorbidity, determined using the ACE27 comorbidity metric, comprised the study cohort. A Fine and Gray competing risks univariable and multivariable regression was used to ascertain whether increasing PPB was associated with an increased risk of PCSM adjusting for age, PSA at randomization, biopsy Gleason score, clinical T-category and treatment received. Cumulative incidence estimates of PCSM describing the impact of treatment with RT alone or RT + ADT

42 Background: Recently men with intermediate-risk prostate cancer (PC) were classified into favorable and unfavorable categories but whether the risk of PC-specific mortality (PCSM) amongst men with high-risk PC is higher compared to men with unfavorable intermediate-risk PC is unknown. Methods: In a prospective randomized trial conducted between 1995 and 2001, 206 men with intermediate or high-risk PC were randomized to 70 Gy with or without six months of androgen suppression therapy (AST). The subgroup of 197 patients with available information on percent positive biopsies formed the study cohort. Fine and Gray’s regression was used to assess whether men with high-risk PC had a significantly higher risk of PCSM compared to men with unfavorable intermediate-risk PC, adjusting for age, treatment, and comorbidity category. Results: After a median follow-up of 14.3 years there were 127 deaths (64.5%), of which 22 (17.3%) were from PC. There were no PC deaths in the favorable intermediate-risk group. There was no significant increase in the risk of PCSM in men with high-risk compared to unfavorable intermediate-risk PC (Adjusted Hazard Ratio: 1.59; 95% Confidence Interval: 0.66 to 3.83; P= 0.30) after adjusting for age, randomized treatment arm and comorbidity. Conclusions: Given no significant difference in the risk of PCSM in unfavorable intermediate compared with high-risk PC, these patients may merit treatment with RT and long-term AST. The lack of PC deaths in the favorable intermediate-risk group suggests that adding AST may not reduce the risk of PCSM in these patients. [Table: see text]

164 Background: Men with highest Gleason Score (GS) ≥ 7 and a lower GS (Combo GS) have a decreased risk of prostate cancer (PC) specific mortality (PCSM) following radiation therapy (RT) or RT and androgen deprivation therapy (ADT). Whether this risk is modulated based on the greatest percent involved core length (GPC) is unknown and investigated in the current study. Methods: The study cohort consisted of 333 men with GS ≥ 7 PC consecutively treated between 12/1989 and 7/2000 using RT (n = 268; 80%) or RT and 6 months of ADT (n = 65; 20%). Biopsy core and tumor lengths were used to calculate the GPC. Competing risks regression assessed whether increasing GPC was associated with an increased risk of PCSM in men with or without ComboGS adjusting for prognostic factors, age, and treatment. Results: After a median follow-up of 5.36 years (IQR: 3.22-7.61 years) 92 (28%) men died, 28 (30%) from PC. Increasing GPC was significantly associated with an increased risk of PCSM (AHR: 1.02; 95%CI: 1.00, 1.03; p=0.02) (Table). Men with GPC ≥ 50% vs. < 50% had significantly higher estimates of PCSM when ComboGS was present (p< 0.001) vs. absent (p=0.55). Of the 127 men with ComboGS and GPC < 50%, 83% were treated with RT alone and 2 PC deaths were observed; none in men with GS 7 and favorable intermediate-risk PC. Conclusions: Men treated with RT for ComboGS, GPC < 50%, GS 7 and favorable intermediate-risk PC may not require ADT to reduce the risk of PCSM. [Table: see text]

Background The National Comprehensive Cancer Network (NCCN) guidelines recommend radiotherapy as a standard treatment for patients with a high risk of recurrence in gastric cancer. Because gastric cancer demonstrates limited sensitivity to radiotherapy, a radiosensitizer might therefore be useful to enhance the radiosensitivity of patients with advanced gastric carcinoma. In this study, we evaluated if propranolol, a β-adrenoceptor (β-AR) antagonist, could enhance radiosensitivity and explored its precise molecular mechanism in gastric cancer cells. Methods Human gastric adenocarcinoma cell lines (SGC-7901 and BGC-823) were treated with or without propranolol and exposed to radiation. Cell viability and clonogenic survival assays were performed, and cell apoptosis was evaluated with flow cytometry. In addition, the expression of nuclear factor κB (NF-κB), vascular endothelial growth factor (VEGF), cyclooxygenase 2 (COX-2), and epidermal growth factor receptor (EGFR) were detected by western blot and real-time reverse transcription polymerase chain reaction (PCR). Results Propranolol combined with radiation decreased cell viability and clonogenic survivability. Furthermore, it also induced apoptosis in both cell lines tested, as determined by Annexin V staining. In addition, treatment with propranolol decreased the level of NF-κB and, subsequently, down-regulated VEGF, COX-2, and EGFR expression. Conclusions Taken together, these results suggested that propranolol enhanced the sensitivity of gastric cancer cells to radiation through the inhibition of β-ARs and the downstream NF-κB-VEGF/EGFR/COX-2 pathway.