Citations

Abstract Taselisib is a potent and selective tumor growth inhibitor through PI3K pathway suppression. Thirty-four patients with locally advanced or metastatic solid tumors were treated (phase I study, modified 3+3 dose escalation; 5 cohorts; 3–16 mg taselisib once-daily capsule). Taselisib pharmacokinetics were dose-proportional; mean half-life was 40 hours. Frequent dose-dependent, treatment-related adverse events included diarrhea, hyperglycemia, decreased appetite, nausea, rash, stomatitis, and vomiting. At 12 and 16 mg dose levels, dose-limiting toxicities (DLT) were observed, with an accumulation of higher-grade adverse events after the cycle 1 DLT assessment window. Pharmacodynamic findings showed pathway inhibition at ≥3 mg in patient tumor samples, consistent with preclinical PIK3CA-mutant tumor xenograft models. Confirmed response rate was 36% for PIK3CA-mutant tumor patients with measurable disease [5/14: 4 breast cancer (3 patients at 12 mg); 1 non–small cell lung cancer], where responses started at 3 mg, and 0% in patients with tumors without known PIK3CA hotspot mutations (0/15). Significance: Preliminary data consistent with preclinical data indicate increased antitumor activity of taselisib in patients with PIK3CA-mutant tumors (in comparison with patients with tumors without known activating PIK3CA hotspot mutations) starting at the lowest dose tested of 3 mg, thereby supporting higher potency for taselisib against PIK3CA-mutant tumors. Cancer Discov; 7(7); 704–15. ©2017 AACR. See related commentary by Rodon and Tabernero, p. 666. This article is highlighted in the In This Issue feature, p. 653

668 Background: Ramucirumab is a human IgG1 monoclonal antibody antagonist of VEGFR-2. Overall survival (OS) and progression-free survival (PFS) in 2nd line FOLFIRI based treatment for metastatic colorectal cancer (mCRC) were improved with RAM therapy versus PBO in the RAISE trial. Recent work suggests mCRC primary tumor location is both prognostic and predictive; with improved OS and therapy-specific sensitivity observed in left (L)- vs right (R)-sided tumors. Given these findings, the RAISE trial data was subjected to post-hoc analysis to determine if sidedness influenced RAM efficacy. Methods: Primary tumor site was obtained. L-CRC was defined as the splenic flexure, descending and sigmoid colon, and rectum, while R-CRC included transverse, ascending colon and cecum. OS/PFS in L and R subgroups were analyzed via Kaplan-Meier method and unstratified log-rank test (treatments within subgroup), unstratified Cox proportional hazards model (estimate hazard ratio [HR] and 95% CI), and Wald test (treatment-by-subgroup interaction). Results: Tumor location was available for 1012/1072 (94%) patients, 699 L- and 313 R-CRC. Baseline characteristics were balanced between arms. RAM treatment enhanced L-CRC median OS by 2.5 mo (median 14.5 vs 12.0 mo) with a HR (95% CI) = 0.807 (0.675, 0.965), P = 0.019; compared to a 1.1 mo increase in median OS in R-CRC vs PBO (12.7 vs 11.6) with a HR (95% CI) = 0.971 (0.750, 1.258), P = 0.823; and, RAM enhanced L-CRC median PFS by 1.6 mo (6.0 vs 4.4 mo) and HR (95% CI) = 0.776 (0.664, 0.906), P = 0.001 compared to a 1.1 mo increase in median PFS R-CRC vs PBO (5.6 vs 4.5) with a HR (95% CI) = 0.855 (0.674, 1.084), P = 0.197. The treatment-by-subgroup interaction for both OS and PFS was not significant ( P = 0.276, 0.578, respectively). Conclusions: Despite L-CRC patients having longer OS/PFS and a seemingly stronger RAM treatment effect than R-CRC, the non-significant interaction test cannot verify sidedness as being predictive of RAM efficacy. The current study confirms ramucirumab benefits mCRC patients regardless primary tumor location. Clinical trial information: NCT01183780.

140 Background: High-risk prostate cancer (HRPC) is a challenging disease and the role of surgery is often considered in the context of a multimodal approach but patients with positive section margins (R1) disease have not always the same cancer-specific survival (CSS). The current study aims to analyze current postoperative pathological features in order to predict CSS of HRPC patients with R1, but with negative lymph nodes (pN0), treated with surgery. Methods: From a multi-institutional retrospective cohort of 5,876 HRPC patients treated by radical prostatectomy and pelvic lymph node dissection, 1541 patients with pN0 and R1 were selected. Following surgery, adjuvant EBRT and/or ADT were delivered according to institutional protocols. Patients were subdivided into four groups according to pT stage (pT≥3 and pT<3) and p-Gleason score (pGS≥8 and pGS<8). Kaplan-Meier plots with log-rank tests and a Cox proportional hazards model were applied to study CSS. All significance levels were set at 0.05. MedCalc was used for all statistical analyses. Results: Median age at surgery was 66 years (42-89). Of all patients, 399 (25.9%) had GS≥8 and 999 (64.8%) had pT≥3 at definitive histopathology. Patients were classified as COMBO groups: C1 (423; 27.4%; GS<8,pT<3), C2 (674; 43.7%; GS<8, pT≥3), C3 (83; 5.4%; GS≥8, pT<3), C4 (362; 23.5%; GS≥8, pT≥3). Adjuvant EBRT and ADT, respectively, were delivered in C1 3%/5%, C2 15%/21%, C3 21%/20%, C4 28%/40%. Kaplan-Meier plots demonstrated statistically different 10-yr CSS between groups: C1 97%, C2 93.8%, C3 85.1% and C4 77.3% (p<0.0001). COMBO groups were also compared using a Cox model and results are shown in the Table. Conclusions: COMBO groups demonstrated to be able to subdivide margin-positive, pN0 HRPC into 4 demarcated groups with significantly different CSS. This subdivision could be considered an easy-to-use tool which can help for counseling patients for adjuvant treatment strategies. [Table: see text]

114 Background: High-risk prostate cancer (HRPC) is a challenging disease and the role of surgery is often considered in the context of a multimodal approach. The indication for adjuvant therapy after surgery for HRPC patients who have specimen-confined disease (R0, pN0, <pT3b) is still difficult. The current study aims to analyze postoperative pathological features which help to predict CSS in specimen-confined HRPC and thus may aid in the decision to administer adjuvant EBRT or ADT. Methods: From a multi-institutional retrospective cohort of 5876 HRPC patients treated by radical prostatectomy and pelvic lymph node dissection, 1391 patients with specimen-confined disease were selected. Following surgery, adjuvant EBRT and/or ADT were delivered according to institutional protocols. Patients were subdivided into four groups according to pT stage (pT≥3 and pT<3) and final Gleason score (GS≥8 and GS<8). Kaplan-Meier plots with log-rank tests and a Cox proportional hazards model were applied to study CSS. All significance levels were set at 0.05. MedCalc was used for all statistical analyses. Results: Median age was 65 years (43-84). Of all patients, 346 (24.9%) had GS≥8 and 794 (57.1%) had pT≥3 at definitive histopathology. Patients were classified into COMBO groups: C1 (478; 34.4%; GS<8,pT<3), C2 (567; 40.8%; GS<8, pT≥3), C3 (119; 8.6%; GS≥8, pT<3), C4 (227; 16.3%; GS≥8, pT≥3). Adjuvant EBRT and ADT, respectively, were delivered in C1 2%/2%, C2 15%/22%, C3 3%/10%, C4 18%/25%. Kaplan Meier plots demonstrated statistically different 10-yr CSS between groups: C1 97.4%, C2 95.2%, C3 89.9% and C4 84.4% (p<0.0001). COMBO groups were also compared using a Cox model and results are shown in the Table. Conclusions: COMBO groups demonstrated to be able to subdivide specimen-confined HRPC into 4 demarcated groups with significantly different CSS. This subdivision could be considered an easy-to-use tool which can help for counseling patients for adjuvant treatment strategies. [Table: see text]

251 Background: To assess the effect of adjuvant therapy in gallbladder adenocarcinoma (GBC). Methods: Retrospective review was conducted at five institutions to identify pts who had surgery for confirmed dx of GBC from 1985-2008 (N = 189). Pts were excluded if they had chemo alone (N = 8), path other than adenoca (N= 7), carcinoma in situ (N=1), < 30 days of follow-up (N = 2), or missing data (N=14). Of the remaining 156 pts, 58 received surgery only and 98 received adj RT ± chemo. Kaplan-Meier was used for overall survival (OS) and Cox proportional hazards to compare risk factors. Results: Median age of dx was 64.4, 68.0% were female, 37.9% had ≥ stage 2b, 37.2% had + nodes, and 32.1% had + margins. Overall, 35.9% of the patients had simple cholecystectomy (SC) only and 64.1% had radical resection (ER). mOS for pts treated with surgery alone was 49.7 months (95% CI: 24.8 to Inf). On univariate analysis, + margins (HR 2.72, p<0.001) was associated with worse OS, whereas ER compared to SC improved survival in both univariate (HR 0.46, p<0.001) and multivariate (HR 0.53, p=0.033) analyses after adjusting for node/margins, T-stage, adj RT, age, gender, and institution. mOS for the entire cohort vs. adj RT (median 50.4 Gy) ± chemo was 30.7 months (95% CI: 19.2 to 46.9) vs. 26.9 months (95% CI: 15.5 to 39.1). But, compared to surgery alone, the adj group was more likely to have had node +, margin +, or T-stage 3+ (all p<0.001). The adj RT group was also less likely than surgery alone pts to have undergone ER (p = 0.007). On multivariate analysis, decreased OS was also found for node + (HR 2.09, p=0.004), margin + (HR 1.84, p=0.043), and T3/T4 disease (HR 2.37, p=0.002). After adjusting for surgical extent, node, margin, T stage, age, gender, and institution, there was improved OS with adj therapy (HR: 0.43, p = 0.020). When stratified by surgical extent, the risk estimate for adj RT improved OS among those with SC (n=56; HR 0.20, p=0.135) and ER (n=100; HR 0.46, p=0.067), but was not statistically significant. Conclusions: ER was associated with improved OS, whereas node/margin+ and T-stage 3+ were associated with worse survival. In multivariate analysis, adj RT improved OS after surgery. Given the poor prognosis of GBC patients with advanced disease, consideration of adj therapy is appropriate. No significant financial relationships to disclose.

AbstractVascularized lymph node transfer has demonstrated promising results for the treatment of extremity lymphedema. In an attempt to find the ideal donor site, several vascularized lymph nodes have been described. Each has a common goal of decreasing morbidity and avoiding iatrogenic lymphedema while obtaining good clinical results. Herein, we present the preliminary clinical outcomes of an intra‐abdominal lymph node flap option based on the appendicular artery and vein used for the treatment of extremity lymphedema. A 62 year‐old woman with moderate lower extremity lymphedema, on chronic antibiotics because of recurrent infections and unsatisfactory outcomes after conservative treatment underwent a vascularized appendicular lymph node (VALN) transfer. At a follow‐up of 6 months, the reduction rate of the limb circumference was 17.4%, 15.1%, 12.0% and 9% above the knee, below the knee, above the ankle and foot respectively. In addition, no further episodes of infection or other complications were reported after VALN transfer. Postoperative lymphoscintigraphy demonstrated that the VALN flap was able to improve the lymphatic drainage of the affected limb. According to our findings, the use of VALN transfer minimizes donor‐site morbidity, avoids iatrogenic lymphedema and may provide a strong clearance of infection because of the strong immunologic properties of the appendiceal lymphatic tissue in selected patients. Despite these promising results, further research with larger number of patients and longer follow‐ up is needed.