Bergsland, Emily K.

AbstractThis article is the result of the North American Neuroendocrine Tumor Society consensus conference on the medical management of pancreatic neuroendocrine tumors from July 19 to 20, 2018. The guidelines panel consisted of medical oncologists, pathologists, gastroenterologists, endocrinologists, and radiologists. The panel reviewed a series of questions regarding the medical management of patients with pancreatic neuroendocrine tumors as well as questions regarding surveillance after resection. The available literature was reviewed for each of the question and panel members voted on controversial topics, and the recommendations were included in a document circulated to all panel members for a final approval.

4005 Background: Patients (pts) with progressive advanced well-differentiated neuroendocrine tumors arising outside of the pancreas have limited systemic treatment options. Pazopanib (PZ) is an oral multi-kinase inhibitor with activity against VEGFR-2,-3, PDGFR-α, and β, and c-KIT, with initial data suggesting efficacy in CARC. Methods: This was a multicenter, randomized, double-blind, phase II study of PZ (800 mg/day) versus placebo (PL) in progressive CARC. Key eligibility: low-intermediate grade CARC, radiologic progressive disease (PD) < 12 months (mo), and adequate end-organ function. Prior somatostatin analog (SSA) mandated for midgut tumors. Concurrent SSA allowed if previous PD on SSA documented. Primary endpoint was progression-free survival (PFS), defined as time from randomization to PD by central review or death. Secondary endpoints included overall survival (OS), objective response rate (ORR) and safety. The trial had 85% power to detect a difference in median PFS of 14 v 9 mo (hazard ratio [HR] 0.64) at one-sided alpha = 0.1. A stratified log-rank test based on the intend-to-treat (ITT) principle was used. Unblinding and crossover were allowed if PD confirmed by central review. Results: 171 (97 PZ, 74 PL) pts were randomized between 6/2013-10/2015: median age 63; 56% female; 66% small bowel primary; 87% concurrent SSA. Median follow-up of 31 mo; 112 (56 PZ, 56 PL) PFS events observed. 6 pts (4 PZ, 2 PL) remain on initial treatment. Median PFS was 11.6 and 8.5 mo in PZ and PL, respectively (HR = 0.53, 1-sided 90% upper confidence limit [UCL] 0.69, p = 0.0005) which crossed the pre-specified protocol efficacy boundary. 49 PL pts received PZ after PD. Median OS was 41 and 42 mo in PZ and PL, respectively (HR = 1.13, 1-sided 90% UCL 1.51, p = 0.70). RR data will be presented. Notable grade 3+ adverse events were (PZ v. PL %) hypertension (35 v. 8), fatigue (11 v. 4), ALT (10 v. 0), AST (10 v. 0), and diarrhea (7 v. 4). Conclusions: PZ compared to PL was associated with significant improvement in PFS in patients with progressive CARC. The results confirm that VEGF signaling pathway is a valid target for therapy in CARC. Support: U10CA180821, U10CA180882 https://acknowledgments.alliancefound.org . Clinical trial information: NCT01841736.

321 Background: G3 NENs are aggressive, and optimal systemic treatment is unclear. Temozolomide (TEM)-based regimens have been used to treat grade 1-2 NETs, but their efficacy in G3 NENs (Ki-67 > 20%) remains undetermined. Aims: To assess the clinical efficacy of TEM-containing regimens in advanced grade III gastroenteropancreatic NENs (GEPNENs). Methods: A multicentre retrospective review (2008-2017) of patients with metastatic/unresectable G3 GEPNENs who received a TEM-containing regimen. The primary endpoint was time to treatment failure (TTF). Radiologic response was extracted from local reports without formal RECIST criteria. Results: 118 patients in six centers were included (median age 55, 65% male, 15% functional, 75% pancreatic NEN). 57% were well-differentiated, 35% poorly-differentiated, and 18% unknown based on local pathology reports. The regimen used was CAPTEM in 93% and TEM in 7%. Best radiological responses were: complete response (1%), partial response (39%), stable disease (22%), progressive disease (31%), unknown (7%) not by RECIST. Median TTF was 150 days and median overall survival (OS) 18.0 months. Fifteen patients (14%) required dose reductions/discontinuation due to adverse events. TTF was shorter for patients on TEM alone (p = 0.02, Table 1). Well-differentiated NENs had better response rate (52% vs 26%, p = 0.02) and overall survival (30.1 vs 12.0 mo, p = 0.008) compared to poorly-differentiated NEN. Conclusions: This is the largest TEM treatment series in G3 NEN, involving collaboration of several major North American NET centers. 40% of patients showed some degree of response, and treatment was generally well-tolerated. TEM-based regimens should be considered a viable treatment option in this setting. Prospective confirmatory trials (such as EA2142) may face difficulties in accrual due to disease rarity. [Table: see text]