Wong, Yu‐Ning

4526 Background: Standard methotrexate, vinblastine, doxorubicin and cisplatin (MVAC) demonstrates a survival benefit in the neoadjuvant setting for patients (pts) with muscle invasive bladder cancer (MIBC). Compared with standard MVAC, AMVAC yielded higher response rates with less toxicity in the metastatic setting. Methods: Pts with MIBC, cT2-T4a, and N0-N1 with CrCl >=50 and adequate hepatic and marrow function were eligible. Pts received 3 cycles of AMVAC (methotrexate 30 mg/m2, vinblastine 3 mg/m2, doxorubicin 30 mg/m2, cisplatin 70mg/m2) on day 1, with pegfilgrastim 6 mg day 2 or 3, every 2 weeks. Pts with CrCl < 60 could receive cisplatin split over 2 days. Radical cystectomy (RC) with lymph node dissection was performed 4-8 weeks after the last dose of chemotherapy. Primary endpoint was pathologic complete response (pCR) rate. Results: Accrual is complete with 44 MIBC pts enrolled at 2 institutions (FCCC, TJU) over a 25 month period. Median age 64 (range 45-83). Three withdrew from study early and are not evaluable for response (2 physician discretion, 1 withdrawal of consent). An additional 8 are currently receiving treatment on study with toxicity and response data pending. Of the 33 evaluable pts for whom final data is available, 30 received all 3 cycles of AMVAC at full dose. Three pts received < 3 cycles due to grade 3 fatigue (1), low platelets (1), and disease progression precluding RC (1). 32/33 pts underwent RC, all within 8 weeks of last chemotherapy. Median time from start of chemotherapy to RC was 9.7 wks (range 4.6-13 wks). 13/33 pts (39.4%, 95% CI, 22.7-56.1%) had a pCR. An additional 3 (9.1%) were downstaged to non muscle invasive disease. For the intent to treat cohort (n=36) 8 pts had grade 3-4 AMVAC related adverse events, the most common being anemia (3), fatigue (3) and neutropenia (2) and overall pCR rate was 36.1%. (95% CI, 20.4-51.8%). All pts will have completed study treatment by April 2012. Final results will be presented. Conclusions: Neoadjuvant AMVAC is well tolerated and preliminary results show a pCR rate similar to that reported for standard 12-week MVAC, suggesting that AMVAC for three cycles (6 weeks) is a safe and efficient alternative.

181 Background: To evaluate whether metformin (Met) a widely-used, nontoxic oral antidiabetic drug with putative anticancer properties leads to improvements in prostate cancer (PC) outcomes in the CHAARTED trial. Methods: In the CHAARTED database where metformin use at baseline was recorded prospectively, we identified patients with metastatic PC who underwent either ADT alone or ADT and docetaxel (D) chemotherapy. Cox proportional hazards models were used to determine the effect of Metformin on outcomes. Results: A total of 788 patients (median age, 63 y) had complete data after randomization. Comparison of ADT+D+Met (n = 39) to ADT+D (n = 357) and ADT+Met (n = 29) to ADT alone (n = 363) revealed similar clinicopathologic characteristics. Cause of death was PC in 13(81%) of ADT+D+Met, 72(85%) ADT+D, 9(82%) ADT+Met and 105(84%) ADT alone groups. See table for PC outcomes and overall survival by metformin use. Cox regression analysis for overall survival stratified by stratification factors at randomization demonstrates Met use was associated with a trend for worse overall survival (HR 1.47 95%CI: [0.95,2.26], p = 0.08) with adjustment for treatment arm and prior local therapy. In contrast, ADT+D use (HR 0.62; 95%CI: [0.47,0.81]) and prior local therapy with surgery or radiation (HR 0.56; 95% CI: [0.38, 0.82]) were associated with improved survival. Conclusions: In this study, baseline metformin did not improve PC outcomes. Partial support and drug supply by Sanofi. Clinical trial information: NCT00309985. [Table: see text]

137 Background: Prior work from SWOG 9346 revealed that PSA ≤ 0.2 ng/dL at 7 months (mo) is prognostic for longer OS with ADT alone. We sought to evaluate if this optimal decline remained predictive of better OS when D was added to ADT for initial mHSPC treatment. Methods: We performed a landmark survival analysis at 7 mo using the E3805 database (NCT00309985). Inclusion required at least 7 mo of followup and PSA levels at 7 mo from ADT initiation. Survival was defined from ADT start or randomization to death. SWOG 9346 PSA nadirs of ≤ 0.2, > 0.2-4 and > 4 were used as classifiers. Results: 719 patients were eligible for analysis: 358 treated with ADT plus D and 361 with ADT alone. Median follow-up was 23.1 mo. On multivariable analysis (MVA), achieving a PSA ≤ 0.2 at 7 mo was more likely if the patient received D and had lower volume disease, prior local therapy, and lower baseline PSAs (all p ≤ 0.01). Across all patients, median OS was significantly longer if PSA at 7 mo reached ≤ 0.2 compared to > 4 (p < 0.0001) (Table). On MVA, PSA ≤ 0.2 at 7 mo and low volume disease were prognostic of longer OS (all p < 0.01). On ADT, 28.8% achieved a PSA ≤ 0.2 at 7 mo vs. 45.3% on ADT+D. Patients on ADT alone who achieved a PSA nadir ≤ 0.2 had the best survival. These patients were more likely to have low volume disease (56.7%) compared to the ADT + D pts (46.3%). Conclusions: Achieving PSA ≤ 0.2 at 7 mo remains prognostic for longer OS with ADT for mHSPC, whether administered alone or with D. Adding D to ADT increased the likelihood of a lower PSA and improved survival. Partial support and drug supply by Sanofi. Clinical trial information: NCT00309985. [Table: see text]

503 Background: We evaluated temporal patterns in the utilization of systemic therapy among patients undergoing cytoreductive nephrectomy (CN) for metastatic Renal Cell Carcinoma (mRCC) from a large national cancer registry and assessed patient characteristics associated with receipt of systemic treatment. Methods: We reviewed the National Cancer Database to identify patients with stage IV RCC who underwent CN between 1998-2010. Systemic therapy was defined as any treatment with immunotherapy and/or chemotherapy (including targeted agents). We evaluated the association between clinicopathologic features and receipt of systemic therapy using multivariable logistic regression with generalized estimating equations, and assessed the interaction of treatment with time, stratified as immunotherapy (1998-2004) versus targeted-therapy (2005-2010) eras. Results: Of 22,409 patients with mRCC undergoing CN, 8,830 (39%) received systemic therapy. Receipt of systemic therapy increased from 32% in 1998 to 49% in 2010 (p<0.001), largely due to increased utilization of chemotherapy (13.9% vs. 46.7%; p<0.001). Following adjustment, increasing patient age (51-60 years: OR 0.82 [CI 0.73-0.92]; 61-70 years: OR 0.67 [CI 0.59-0.76]; ≥71 years: OR 0.36 [CI 0.31-0.43]), as well as coverage with Medicaid (OR 0.61 [CI 0.5-0.74]), Medicare (OR 0.70 [CI 0.62-0.79]), or no insurance (OR 0.75 [CI 0.63-0.91]) were associated with decreased utilization of systemic therapy. Although use of systemic therapy in the elderly (≥71 years) and in patients with Medicare/Medicaid remained lower throughout the study period, each of these cohorts was significantly more likely to receive systemic treatment in the targeted versus immunotherapy era (all p values <0.05). Conclusions: Utilization of systemic therapy among patients undergoing CN has increased over time, coinciding with the introduction of targeted therapies. Nevertheless, still less than half of such patients receive systemic treatment. While the etiology for lack of treatment is likely multifactorial, the potential health policy implications of continued disparities in care warrant further investigation.

LBA2 Background: Docetaxel (D) improves OS of men with mPrCa who have progressed on androgen deprivation therapy (ADT). We aimed to assess the benefit of upfront chemohormonal therapy for metastatic PrCa. Methods: 1:1 randomization to ADT alone or ADT + D dosed 75mg/m2 every 3 weeks for 6 cycles within 4 month (mos) of starting ADT. Stratification factors: high volume (HV) vs. low volume (LV) disease (HV: visceral metastases and/or 4 or more bone metastases); anti-androgen use beyond 30 days; Age ≥70 vs. < 70 years; ECOG PS 0-1 vs. 2; Prior adjuvant ADT > 12 vs. ≤ 12 mos; FDA approved drug for delaying skeletal related events. Key eligibility criteria: suitable organ and neurological function for D; adjuvant ADT ≤ 24 mos and no progression within 12 mos of adjuvant ADT. OS was the primary endpoint and the study was powered to assess for a 33.3% improvement in median OS (80% power and 1-sided alpha=2.5%). Projected median OS for ADT alone: HV-33 mos; LV-67 mos. Results: 790 men were accrued from 7/28/06 to 11/21/2012: ADT N=393; ADT + D: N=397; balanced for demographic, stratification and disease factors. Median age: 63 years (range: 36 to 91); 98% ECOG PS 0 or 1; 89% Caucasian; 24% prior radiotherapy, 24% prior prostatectomy; HV 64% on ADT and 67% on ADT + D. Data released after 4th interim analysis in Sept 2013 when O’Brien Fleming upper boundary was crossed with 53.1% information. This report reflects 1/16/2014 data with median follow-up of 29 mos with 137 deaths on ADT alone vs. 104 deaths on ADT+D. ADT+D: Grade (G) 3/4 Neutropenic fever: 4%/2%; G3 neuropathy: 1% sensory, 1% motor; 1 death due to treatment (no deaths due to treatment on ADT). Efficacy data is in the table below. After disease progression, 123 pts on ADT alone and 45 pts on ADT + D received docetaxel. Conclusions: ADT + D improves OS over ADT alone in men with HV mPrCa. Longer follow-up is needed for men with LV mPrCa. Clinical trial information: NCT00309985. [Table: see text]