Citations

243 Background: Cbz/pred extends survival in mCRPC patients (pts) following docetaxel and first-line studies comparing Cbz to docetaxel are ongoing. Mito/pred also has anti-tumor activity in mCRPC and a non-overlapping mechanism of action and toxicity profile with Cbz. A multicenter phase I trial was initiated through the DOD PCCTC to establish the maximally tolerated dose (MTD) of the combination of Cbz, Mito, and Pred. Methods: Chemotherapy (chemo)-naive pts with mCRPC were enrolled in an accelerated titration design. The primary objective was to determine the MTD of CAMP; secondary objectives included assessing PSA and objective response rates and duration of response. Starting dose of Cbz was 25 mg/m2 (the currently approved single-agent dose) and Mito 4 mg/m2, administered on day 1 of a 21-day cycle. Mito was escalated by 2 mg/m2 per dose level. Pred 5 mg BID and pegfilgrastim were administered with each cycle. Results: 9 pts were enrolled (dose level I, N = 1; dose level II, N = 1; dose level III, N = 3; dose level IV N = 4). The median age was 67 (range 55-81) and the median baseline PSA was 82.3 (range 20.4-791.2). There were 2 DLTs observed at dose level IV (Cbz 25 mg/m2 + mito 10 mg/m2), both grade 4 sepsis. The most common grade 3 adverse events were hematologic (neutropenia, n = 5; febrile neutropenia, n = 2, thrombocytopenia, n = 2). 6 of 9 pts remain on study (range 2.2 - 10.5+ months). Maximal PSA declines from baseline > 50% have been observed in 4/7 (57%) evaluable pts to date. 2 of 4 pts with measurable disease have experienced partial responses and a third has had a minor response after 4 cycles of chemo. The median progression-free survival and duration of response have not been reached. Conclusions: The approved single-agent dosage of Mito (12 mg/m2) could not be safely reached in combination with Cbz 25 mg/m2. Pre-planned evaluation of an alternate dosing strategy combining Mito with Cbz 20 mg/m2, which has demonstrated activity in mCRPC and potentially less hematologic toxicity, is underway. Preliminary efficacy data are encouraging but additional follow-up and further study of the treatment combination is required. Clinical trial information: NCT01594918.

61 Background: Patients with cancer often have complex symptoms and morbidity that prompt frequent Emergency Department visits. The length of stay in the ED for cancer patients exceeds that of patients without cancer. Patients with cancer are also more likely to be admitted, but are often discharged within 72h. Protracted ED visits, extensive investigations, and the burdens of even a short admission may be distressing and may not be aligned with patients’ care goals and preferences. Furthermore, the healthcare resources dedicated to these patients is considerable and has economic implications. We recently established a Supportive Care Infusion Center (SCIC), an on-campus outpatient unit where patients can receive treatments for symptom relief and comfort; they are assured integrated palliative care with routine oncologic care. We believe there is a subset of cancer patients who can be safely transferred from the ED to the SCIC for appropriate care. Methods: We are retrospectively evaluating cancer patients admitted through the ED to validate clinical parameters likely to lead to admission, and also identify any differences between patients admitted for <72h vs >72h. Patients are analyzed based on symptoms, cancer type, prior cancer therapies, performance status, comorbidities, and presence/absence of advance care planning as well as previous contact with Palliative Care. Data are also being gathered on patient outcomes, including mortality within 60d of admission. Results: Previously established indicators predictive of admission included shortness of breath and SIRS criteria, which our current review validates. We also observe that patients admitted for >72h have greater symptom burden and comorbidities and have received multiple lines of therapy. They also less frequently have advance care planning in place. Data analysis is ongoing. Conclusions: There exists a difference between cancer patients admitted >72h and those discharged within 72h. Awareness of these characteristics may lead to improved workflow in the ED. Identifying patients who may be suitable for transfer to an outpatient supportive care unit rather than short-term admission will also facilitate cost-effectiveness. Future direction includes evaluation of outcomes such as mortality, quality of life, and patient-caregiver satisfaction.

42 Background: Methods of stratifying esophageal adenocarcinoma patients into prognostic groups are needed, as are new insights into genetic determinants of disease behaviour. Prognosis is likely to have non-negligible genetic influences, as mediated by host responses to tumor, resistance to therapeutic side-effects, and/or an influence on tumor development. Prior studies have used candidate-gene approaches. We took an alternative approach, using an unbiased, genome-wide approach, and novel analytic methods that may be better able to detect multi-gene interactions, which may contribute the majority of genetic effects for many clinical phenotypes. Methods: Germline DNA from a Toronto-based cohort of EAC patients (n=270) was analyzed by Omni1 Quad microarray as part of the BEAGESS initiative. Quality control and analysis was performed using PLINK, R, and GenABEL software packages. A Cox proportional hazards (CPH) model for progression-free survival tested each polymorphism for independent effects at a genome-wide significance level of P < 1E-07, adjusting for population stratification. While classical analysis has limited ability to detect gene-gene interactions, a Random Survival Forest algorithm was used to detect effects based on the complex interactions among top 1,000 polymorphisms by p-value ranking. Results: After data cleaning and standard GWAS quality control procedures, there were 735,309 SNPs and 245 patients remaining for analysis. The CPH model, adjusted for population stratification, produced a satisfactory Q-Q plot, and showed one SNP (rs7844673, Chr 8) that was significant at p=7.8E-8. In addition, Random Forest based variable selection produced a set of 20 polymorphisms that (1) reproduced 86% of the predictive ability of the full 1000 variables, and (2) also included the #3 ranked polymorphism by CPH modeling (rs9290822, Chr 3) upstream of the IGF2BP2 gene. Conclusions: A genome-wide approach has discovered two previously undescribed SNPs with a potential influence on EAC prognosis via a combination of independent and interactive effects. Validation in an independent cohort is currently being pursued.

CRA1002 Background: Weekly P is superior to q 3 week (wk) dosing, and adding B improves progression free survival (PFS) (E2100). Ix is a potent epothilone that can be effective after microtubule inhibitor resistance. NP is a novel albumin-bound formulation of P with promising activity in the first-line MBC setting. In this phase III trial, the efficacy of weekly Ix or NP is compared to P, in combination with B in patients (pts) with chemotherapy (CTX) naïve MBC. Toxicity including >Grade 2 sensory neuropathy (SN) is compared to P. Methods: Pts were randomized 1:1:1 to receive P (90 mg/m2), Ix (16 mg/m2) or NP (150 mg/m2) on a 3 wk on, 1 wk off schedule, stratified by prior adjuvant taxane use and hormone receptor status. B was initially given to all pts, but became optional in 3/2011 and was added to stratification. The primary end point of PFS is defined as time from randomization to progression or all-cause death. With a target N=900 pts, the study was powered to detect a hazard ratio (HR) of 1.36 (median PFS 10 vs 13.6 mos). Eligibility included no prior CTX for MBC, >12 mos from adjuvant P and measurable disease. Results: 799 pts were enrolled between 11/08-11/11 (283 to P, 271 to NP, 245 to Ix); 98% received B. 72% had ER+ disease, 44% received adjuvant P. At the 1st interim analysis (165 events) the comparison of Ix to P crossed the futility boundary (FB) and accrual to Ix was closed. At the 2nd interim analysis (236 events), NP to P crossed the FB and the study was closed on 11/30/11. Median PFS was 10.4, 9.6 and 7.6 mos for P, NP and Ix, with HRs (95% CIs) of 0.94 (0.73-1.22) and 0.66 (0.51-0.84) for P to NP and Ix respectively. Grade 2+ SN was 48% for NP, 44% for Ix and 37% for P; Grade 3+ hematologic toxicity was 49% for NP, 20% for Ix, and 12% for P. Conclusions: In pts with CTX naive MBC, both NP and Ix are highly unlikely to be superior to P for PFS (when all are combined with B), and in combination with B, weekly P is the better tolerated drug. Toxicity including SN was greater in each experimental arm compared to P. Updated data will be presented, and correlative studies will be reported at a future date.

535 Background: The most effective management of locally recurrent colorectal cancer (CRC) is resection. This is also true for hepatic metastases (HM). Data remains limited, however, regarding concomitant resection of recurrent CRC and HM. The aims of this study were to determine the feasibility, safety and outcomes in terms of disease-free survival (DFS) and overall survival (OS) in patients undergoing concomitant resection of recurrent CRC with HM. Methods: All patients who underwent resection of recurrent CRC from 1/1995 to 1/2007 at Mayo Clinic, Rochester were reviewed (n=406). The study group consisted of patients who underwentconcomitant resection of locally recurrent CRC and hepatic resection for metastatic CRC (n= 45). Kaplan-Meier Survival was used to estimate DFS and OS. Results: The study group consisted of 27 men and 18 women. The median age was 59 years. Surgical management involved pelvic dissection in 43 patients and ileotransverse colectomy in two. 17 patients required resection of contiguous organs. 24 patients received intra-operative radiation. 34 patients underwent multiple hepatic wedge resections, 6 patients segmentectomy, 3 left hepatectomy, and 2 right hepatectomy. There was no perioperative mortality. Morbidity was 37%, 2 patients required re-operation. The 1, 3, and 5 year DFS was 72.2, 42.3, and 18.5%, respectively. The 1, 3, and 5 year OS was 87.7, 47.6, and 36.2%, respectively. Conclusions: Synchronous resection of locally recurrent CRC and HM is safe and feasible; morbidity is reasonable and mortality zero. DFS and OS in this patient population appear comparable to that of patients undergoing separate, staged resections.

467 Background: Regorafenib (REG) is an oral multikinase inhibitor that has recently demonstrated significant overall survival benefit vs placebo in the randomized phase III CORRECT study. We examined the time course of adverse events (AEs) in the CORRECT study. Methods: Regorafenib (REG) is an oral multikinase inhibitor that has recently demonstrated significant overall survival benefit vs placebo in the randomized phase III CORRECT study. We examined the time course of adverse events (AEs) in the CORRECT study. Results: The safety population comprised 753 patients (pts): REG n=500; placebo n=253. The mean treatment duration was 12.1 ± 9.7 weeks in the REG group and 7.8 ± 5.2 weeks in the placebo group. Treatment-emergent AEs occurred at any grade in 99.6% of REG pts and 96.8% of placebo pts, at grade 1/2 in 21.6% and 47.8%, respectively, at grade 3 in 56.0% and 26.5%, respectively, and at grade 4/5 in 22.0% and 22.5%, respectively. AEs occurring in ≥10% more REG than placebo pts were fatigue, hand–foot skin reaction (HFSR), anorexia, diarrhea, weight loss, voice changes, hypertension, rash/desquamation, oral mucositis, fever, hyperbilirubinemia, low platelet count. The most frequent AEs deemed to be regorafenib related were HFSR, fatigue, diarrhea, hypertension, and rash/desquamation. The frequency of these AEs over time is shown in the Table. The incidence of HFSR, fatigue, hypertension, and rash/desquamation peaked in cycle 1 and tapered to a relatively stable lower incidence over later cycles. The incidence of diarrhea remained relatively constant throughout treatment. AEs led to dose modification in 66.6% of pts in the REG group and 22.5% in the placebo group. Data on dose intensity across treatment cycles will be presented. Conclusions: In the CORRECT trial, the incidences of the most common AEs in the REG group peaked early during treatment. There appeared to be no evidence for cumulative toxicity of REG. Clinical trial information: NCT01103323. [Table: see text]

381 Background: In the CORRECT Ph3 trial, regorafenib demonstrated significant improvement in OS and PFS vs. placebo in subjects with metastatic colorectal cancer (mCRC) who had progressed on standard therapies. An exploratory biomarker substudy was conducted on samples collected from subjects enrolled in CORRECT. Methods: DNA was isolated from archival tumor tissue and fresh baseline plasma samples that were available from 239 (31%) and 503 (66%) subjects enrolled in CORRECT, respectively. Mutations in KRAS, PIK3CA and BRAF were evaluated via BEAMing technology. Results: Mutations were readily detected in DNA isolated from both tumor and plasma samples: KRAS: 59/69%; PIK3CA: 12/17% and BRAF: 1.5/3.4%. The frequency of KRAS mutation detected in tumor samples via BEAMing (59%) was identical to the frequency determined from pre-existing “historical” KRAS mutation data that was available from 96% of the subjects enrolled in the study. Concordance among the mutations detected via BEAMing in tumor vs. plasma was 76% (KRAS), 88% (PIK3CA), and 97% (BRAF). A subset of CRC which was found to be KRAS-wildtype in DNA from archival tumor, but KRAS-mutant in DNA from fresh plasma was identified and may represent subjects whose KRAS mutational status had changed during prior therapy. Correlative subgroup analyses demonstrated that regorafenib mediated a trend for clinical benefit vs. placebo in both KRAS wildtype and mutant subgroups identified by plasma BEAMing (OS: KRAS WT, HR: 0.67, 95% CI: 0.41–1.08; KRAS mutant, HR: 0.81, 95% CI: 0.61–1.09; interaction p=0.561). Similar results were noted for PIK3CA WT/mutant subgroups (OS: WT, HR: 0.75, 95% CI: 0.57–0.99; mutant, HR: 0.84, 95% CI: 0.47–1.50; interaction p=0.723). BRAF was not analysed due to the small number of BRAF-mutant samples. Conclusions: The mutational analysis of DNA isolated from fresh plasma is feasible and robust using the BEAMing platform and may better represent the mutational status of the tumor(s) that a mCRC patient harbors at the time of enrollment than does the mutational analysis of archival primary tumor tissue. Regorafenib was associated with clinical benefit (vs. placebo) in all mutational subgroups evaluated. Clinical trial information: NCT01103323.

224 Background: In the phase 3 RADIANT-3 trial, everolimus (EVE) demonstrated significantly improved median progression-free survival (PFS) versus placebo (PBO) (11.0 vs 4.6 months; HR=0.35, p < 0.0001) in patients (pts) with pancreatic neuroendocrine tumors (pNET) (Yao et al, NEJM, 2011). Here we present a planned exploratory analysis by prior chemotherapy (chemo) use. Methods: Pts with progressive low- or intermediate-grade pNET were prospectively stratified by prior chemo use and randomized (1:1) to EVE 10 mg/d (n = 207) or PBO (n = 203) plus best supportive care. Results: Of the 410 pts, 206 (50%) had received prior chemo and 204 (50%) were chemo naive. Baseline characteristics (age, sex, race, tumor type, histologic grade) and baseline tumor biomarker levels were similar for pts with/without prior chemo. More chemo-naive pts were newly diagnosed (time since initial diagnosis ≤ 6 mo: 50 [25%] vs. 7 [3%] pts with prior chemo). A lower proportion of chemo-naive pts received prior somatostatin therapy (45% vs. 54% prior chemo). EVE significantly prolonged median PFS regardless of prior chemo use (with prior chemo: 11.0 vs. 3.2 months; HR = 0.35, 95% CI 0.25-0.49, p < 0.001; chemo naive: 11.4 vs. 5.4 months; HR = 0.42, 95% CI 0.29-0.60; p < 0.001). Stable disease was the best overall response in 73% of EVE-treated pts irrespective of prior chemo use. The benefit from EVE irrespective of prior chemo was further demonstrated by disease stabilization or minor tumor shrinkage and in the lower incidence of progressive disease in waterfall plots. Safety of EVE was consistent regardless of prior chemo use. The most common drug-related adverse events (chemo vs chemo naive) included rash (53% vs. 52%), stomatitis (52% vs. 56%), diarrhea (41% vs. 52%), and fatigue (37% vs. 51%). Conclusions: This planned subgroup analysis demonstrated the beneficial effects of EVE in pts with pNET regardless of prior chemo use. These findings support the possible first-line use of EVE for pts with pNET.

386 Background: Angiogenesis plays a role in tumor growth and is partly mediated by factors in both the fibroblast growth factor (FGF) and vascular endothelial growth factor (VEGF) pathways. Brivanib inhibits both VEGF receptor 2 and FGF receptors (FGFR)-1/2. Methods: Nephrectomy material from 40 patients with metastatic renal cell carcinoma (RCC) receiving sorafenib ± interferon was assessed by immunohistochemical (IHC) staining. The Ariol imaging platform was used to stratify the specimens based on intensity of staining for FGF biomarkers: FGFR-1 and fibroblast growth factor receptor substrate 2 (pFRS2). The relationship between fibroblast growth factor pathway marker levels and progression-free survival (PFS) was analyzed using Kaplan-Meier and Cox proportional hazards regression methods. To assess the efficacy of dual targeting of VEGF and FGF receptor signaling by brivanib, we treated a xenograft RCC mouse model with sunitinib, brivanib, or sunitinib followed by brivanib. Results: Our analysis indicated that more intense FGFR-1 staining was associated with shorter PFS (p = 0.0452), and that pFRS2 staining were not significantly associated with PFS (p = 0.2610). FGF pathway activation was associated with decreased PFS in patients with metastatic RCC treated with sorafenib. Xenograft mice were treated with 20 mg/kg sunitinib and after an initial stabilization phase, resistance developed by day 20. A switch to 30 mg/kg brivanib prolonged the stabilization phase after progression on sunitinib (p = 0.0033). Conclusions: The PFS of patients treated with sorafenib is associated with FGF pathway activation. In a xenograft RCC mouse model, brivanib overcame the tumor escape after initial treatment with sunitinib. Switching from sunitinib to brivanib at the time of tumor escape prolonged the stabilization phase and overcame a sunitinib-induced resistance phenotype. The results suggest that FGF pathway activation mediates both innate and acquired tumor resistance to VEGF receptor inhibition. The efficacy of dual inhibition of FGF and VEGF in the subset of patients with increased FGF activation prior to treatment requires further study.

36 Background: Following radical prostatectomy (RP), 30-40% of patients have adverse pathology and are deemed at high risk for metastatic progression. The objective of this study was to validate the ability of Decipher, a genomic classifier (GC), to improve prediction of metastatic disease progression compared with clinical variables in order to better identify candidates for therapy intensification. Methods: A previously developed 22-feature GC model was validated in a prospectively designed case-cohort study of a clinically high-risk population (i.e., with one or more adverse pathological features) of 1,010 RP patients treated at Mayo Clinic between 2000-2006. A random sample of 20% of the cohort was subjected to microarray analysis and GC scores were generated for 219 patients. The primary endpoint, the c-index for predicting metastatic disease progression (i.e., positive bone or CT scans) was evaluated in a blinded analysis. Cox modeling and decision curve analyses were used to compare the performance of GC to individual clinical variables and prediction models. Results: GC had a c-index 0.79 (95% CI 0.71-0.86) that was significantly better than any single clinical variable. Cumulative incidence curves in the cohort showed that 72% of patients had low GC scores with only 3% and 6% incidence of metastatic disease at 5 and 10 years post RP. In contrast, for the 28% of patients with high GC scores, the cumulative incidence was 17% and 25% at 5 and 10 years post RP. Decision curve analysis showed that the GC model had higher overall net benefit compared to clinical variables over a wide range of ‘decision-to-treat’ thresholds for risk of metastasis. In multivariable modeling with clinicopathologic variables, GC remained the only significant independent predictor of metastasis (HR=1.51, for each 0.1 unit increment, p<0.001). Conclusions: GC can better predict metastatic disease progression compared with clinical variables and may select among patients with adverse pathology a majority that is in fact at low risk for metastasis.