Efficacy, Safety and Biomarker Analysis of Combined PD-L1 (Atezolizumab) and VEGF (Bevacizumab) Blockade in Advanced Malignant Peritoneal Mesothelioma

Malignant peritoneal mesothelioma (MPeM) is a rare but aggressive malignancy with limited treatment options. VEGF inhibition enhances efficacy of immune-checkpoint inhibitors by reworking the immunosuppressive tumor milieu. Efficacy and safety of combined PD-L1 (atezolizumab) and VEGF (bevacizumab) blockade (AtezoBev) was assessed in 20 patients with advanced and unresectable MPeM with progression or intolerance to prior platinum-pemetrexed chemotherapy. The primary endpoint of confirmed objective response rate per RECISTv1.1 by independent radiology review was 40% (8/20; 95%CI:19.1-64.0) with median response duration of 12.8 months. Six (75%) responses lasted for >10 months. Progression-free and overall survival at 1-year were 61% (95%CI:35-80) and 85% (95%CI:60-95), respectively. Responses occurred notwithstanding low tumor mutation burden and PD-L1 expression status. Baseline epithelial-mesenchymal transition gene-expression correlated with therapeutic resistance/response (r=0.80; P=0.0010). AtezoBev showed promising and durable efficacy in patients with advanced MPeM with acceptable safety profile and these results address a grave unmet need for this orphan disease.

Final overall survival in the phase 3 NETTER-1 study of lutetium-177-DOTATATE in patients with midgut neuroendocrine tumors

4112

Background: As demonstrated in the primary analysis of the phase 3 NETTER-1 trial, 177Lu-DOTATATE significantly prolonged progression-free survival (PFS) versus high-dose long-acting octreotide, with a HR of 0.18 (95% CI: 0.11, 0.29; p < 0.0001), in patients with advanced, progressive, well-differentiated, somatostatin receptor-positive midgut neuroendocrine tumors (NETs). Here we report final overall survival (OS) for NETTER-1. Methods: In this international open-label trial, eligible patients were randomized to receive either four cycles of 177Lu-DOTATATE 7.4 GBq (200 mCi) every 8 ± 1 weeks plus long-acting octreotide 30 mg or high-dose long-acting octreotide 60 mg every 4 weeks (control arm), both on top of best supportive care. After disease progression on randomized treatment or completion of an 18-month treatment period, patients in both arms entered long-term follow-up and could receive further anti-cancer treatment as recommended by their physicians. The primary endpoint was PFS per RECIST 1.1 and OS was a key secondary endpoint. Primary intention-to-treat analysis of OS was prespecified to take place after 158 deaths or 5 years after the last patient was randomized, whichever occurred first. Results: Of 231 randomized patients, 101/117 (86.3%) in the 177Lu-DOTATATE arm and 99/114 (86.8%) in the control arm entered long-term follow-up. Final analysis occurred 5 years after the last patient was randomized, following 142 deaths, with a median follow-up of more than 76 months. During long-term follow-up, 41/114 (36%) of patients in the control arm received subsequent radioligand therapy (“cross-over”), the majority (22.8%) within 24 months. Median OS was 48.0 months (95% CI: 37.4, 55.2) in the 177Lu-DOTATATE arm and 36.3 months (95% CI: 25.9, 51.7) in the control arm. HR was 0.84 (95% CI: 0.60, 1.17) with p = 0.30 (unstratified 2-sided log-rank test). A total of 2/112 (1.8%) 177Lu-DOTATATE treated patients in the study developed myelodysplastic syndrome (MDS). No new cases of MDS or acute leukemia were reported in the long-term follow-up. Overall, no new safety signals emerged during long-term follow-up. Conclusions: Median OS was 48.0 months in the 177Lu-DOTATATE arm of the NETTER-1 trial and 36.3 months in the control arm. This difference was not statistically significant, potentially impacted by a high rate (36%) of cross-over of patients in the control arm to radioligand therapy after progression. In overall conclusion, the NETTER-1 study demonstrated that 177Lu-DOTATATE yielded a clinically and statistically significant improvement in PFS as a primary endpoint (HR: 0.18, p < 0.0001) as well as a clinically meaningful trend towards improvement in median OS of 11.7 months. No new safety signals emerged during the 5-year long-term follow-up. Clinical trial information: NCT01578239.

Relationship between metabolic toxicity and efficacy of everolimus in patients with neuroendocrine tumors: A pooled analysis from the randomized, phase 3 RADIANT-3 and RADIANT-4 trials

BACKGROUND

Hyperglycemia and hypercholesterolemia are class effects of mammalian target of rapamycin inhibitors such as everolimus. This post hoc pooled analysis assessed the potential impact of these events on the efficacy of everolimus.

METHODS

Patients with advanced, low- or intermediate-grade pancreatic, gastrointestinal, or lung neuroendocrine tumors received either oral everolimus at 10 mg/d or a placebo in the RAD001 in Advanced Neuroendocrine Tumors 3 (RADIANT-3) and RAD001 in Advanced Neuroendocrine Tumors 4 (RADIANT-4) trials. A landmark progression-free survival (PFS) analysis by central review was performed for patients treated for at least 16 weeks (n = 308) and according to the occurrence of any-grade adverse events (AEs) within this treatment period.

RESULTS

The overall PFS with everolimus from the pooled analysis was 11.4 months (95% confidence interval, 11.01-13.93 months), which was consistent with the findings of RADIANT-3 and RADIANT-4. Overall, 19.1% and 9.8% of patients in RADIANT-3 and 11.9% and 6.4% of patients in RADIANT-4 developed any-grade hyperglycemia and hypercholesterolemia, respectively (regardless of the study drug). The duration of everolimus exposure was longer in patients who developed these AEs versus patients without these AEs. Overall, 308 patients were exposed to treatment for at least 16 weeks (hyperglycemia, 39 of 269 patients; hypercholesterolemia, 20 of 288 patients). No association was observed between the development of these AEs and PFS (18.8 and 14.1 months with and without hyperglycemia, respectively, and 14.1 and 14.8 months with and without hypercholesterolemia, respectively).

CONCLUSIONS

Although limitations apply because of the small number of AEs observed, there was no significant impact of these AEs on PFS; this suggests similar efficacy in the presence or absence of these events.

Recurrence Patterns After Surgical Resection of Gastroenteropancreatic Neuroendocrine Tumors: Analysis From the National Comprehensive Cancer Network Oncology Outcomes Database

OBJECTIVE

Current National Comprehensive Cancer Network guidelines for gastroenteropancreatic neuroendocrine tumors (GEPNETs) recommend complete (R0) surgical resection of the primary tumor and metastases, if feasible. However, large multicenter studies of recurrence patterns of GEPNETs after resection have not been performed.

METHODS

Patients 18 years or older who presented to 7 participating National Comprehensive Cancer Network institutions between 2004 and 2008 with a new diagnosis of a small bowel, pancreas, or colon/rectum neuroendocrine tumor (NET) and underwent R0 resection of the primary tumor, and synchronous metastases, if present, were included in this analysis. Descriptive statistics and Kaplan-Meier estimates were used to calculate recurrence rates and time-associated end points, respectively.

RESULTS

Of 294 patients with GEPNETs, 50% were male, 88% were White, and 99% had Eastern Cooperative Oncology Group performance status 0 to 1. The median age was 55 years (range, 20-90). The median follow-up time from R0 resection was 62.1 months. Recurrence rates were 18% in small bowel NETs (n = 110), 26% in pancreatic NETs (n = 141), and 10% in colon/rectum NETs (n = 50). The frequency of surveillance imaging was highly variable.

CONCLUSIONS

R0 resection was associated with variable risk of recurrence across subtypes. Further research to inform refinement of guidelines for the appropriate duration of surveillance after R0 resection is needed.

Markers of Systemic Inflammation in Neuroendocrine Tumors: A Pooled Analysis of the RADIANT-3 and RADIANT-4 Studies

OBJECTIVE

The aim of the study was to assess the impact of systemic markers of inflammation on the outcomes in patients with neuroendocrine tumors (NETs) treated with everolimus or placebo (as measured by baseline neutrophil-to-lymphocyte ratio [NLR] and lymphocyte-to-monocyte ratio [LMR]).

METHODS

Patient data (gastrointestinal, pancreatic, and lung NETs) from 2 large phase 3 studies, RADIANT-3 (n = 410) and RADIANT-4 (n = 302), were pooled and analyzed. The primary end point was centrally assessed progression-free survival (PFS) as estimated by the Kaplan-Meier method.

RESULTS

In the pooled population, elevated LMR (median PFS, 11.1 months; 95% confidence interval, 9.3-13.7; hazard ratio, 0.69; P < 0.001) and reduced NLR (median PFS, 10.8 months; 95% confidence interval, 9.2-11.7; hazard ratio, 0.75; P = 0.0060) correlated with longer PFS among all patients. These markers were also found to be prognostic in the everolimus- and placebo-treated subgroups.

CONCLUSIONS

Data from this study suggest that LMR and NLR are robust prognostic markers for NETs and could potentially be used to identify patients who may receive or are receiving the most benefit from targeted therapies. As both are derived from a complete blood count, they can be routinely used in clinical practice, providing valuable information to clinicians and patients alike.

FRESCO-2: A global phase III study of the efficacy and safety of fruquintinib in patients (pts) with metastatic colorectal cancer (mCRC)

TPS154

Background: Pts with mCRC have limited treatment options following progression on standard therapies. Current standard of care (SOC) after pts progress on trifluridine/tipiracil (TAS-102) or regorafenib is re-challenge with previous systemic treatments, enrollment in a clinical trial, or best supportive care (BSC). Fruquintinib (Elunate) is a novel, highly selective, vascular endothelial growth factor (VEGF) receptor (VEGFR)-1, -2, and -3 tyrosine kinase inhibitor (TKI) ( Cancer Biol Ther 2014;15:1635-1645). Fruquintinib is approved in China to treat pts with mCRC who received or are intolerant to fluoropyrimidine-, oxaliplatin-, and irinotecan-based chemotherapy, anti-VEGF therapy, and, if RAS wild type, anti-epidermal growth factor receptor (EGFR) therapy. Approval was based on results of the phase 3 FRESCO study (2013-013-00CH1; NCT02314819; JAMA 2018;319:2486-2496), in which fruquintinib 5 mg daily (QD), 3 weeks on, 1 week off (3 on/1 off), significantly improved overall survival (OS) in pts with mCRC in the 3rd-line+ setting when compared to placebo (median OS 9.3 months [mo] versus 6.6 mo; hazard ratio [HR] 0.65; p < .001). Progression-free survival (PFS) was also superior (median PFS 3.7 mo versus 1.8 mo; HR 0.26; p < .001). The toxicities of fruquintinib were consistent with those of other VEGF TKIs and were manageable. At the time FRESCO was conducted in China, SOC for pts with mCRC differed from that in the US, EU, and Japan. We describe here a global phase 3 study (FRESCO-2; 2019-013-GLOB1; NCT04322539) being conducted to investigate fruquintinib’s efficacy and safety in pts with refractory mCRC and a treatment profile representative of the global SOC. Methods: FRESCO-2 is a randomized, double-blind, placebo-controlled study to compare fruquintinib + BSC to placebo + BSC. Key inclusion criteria are progression on or intolerance to treatment with TAS-102 and/or regorafenib; previous treatment with standard approved therapies including chemotherapy, anti-VEGF therapy, and, if RAS wild type, anti-EGFR therapy. Prior therapy with immune checkpoint or BRAF inhibitors is required for pts with corresponding tumor alterations. Pts (~522) will be randomized 2:1 to receive either fruquintinib 5 mg orally (PO) QD + BSC or placebo 5 mg PO QD + BSC, with a 3 on/1 off schedule. Randomization will be stratified by prior therapy, RAS status, and duration of metastatic disease. The primary endpoint is OS; secondary endpoints include PFS, disease control rate, objective response rate, duration of response, and safety. Final OS analyses will be performed when 364 OS events are observed; futility analysis will be conducted with 1/3 (121) OS events. If enrichment of post-regorafenib pts occurs, enrollment to that strata will be capped at approximately 262. FRESCO-2 will be activated in the US, EU, and Japan; global enrollment is anticipated over 13 mo. Clinical trial information: NCT04322539.

Fluorouracil, Doxorubicin with Streptozocin and Subsequent Therapies in Pancreatic Neuroendocrine Tumors

We evaluated outcomes of treatment with 5-fluorouracil (5-FU), doxorubicin, and streptozocin (FAS) in well-differentiated pancreatic neuroendocrine tumors (PanNETs) and its impact on subsequent therapy (everolimus or temozolomide). Advanced PanNET patients treated at our center from 1992 to 2013 were retrospectively reviewed. Patients received bolus 5-FU (400 mg/m2), streptozocin (400 mg/m2) (both IV, days 1-5), and doxorubicin (40 mg/m2 IV, day 1) every 28 days. Overall response rate (ORR) was assessed using RECIST version 1.1. Of 243 eligible patients, 220 were evaluable for ORR, progression-free survival (PFS), and toxicity. Most (≥90%) had metastatic, nonfunctional PanNETs; 14% had prior therapy. ORR to FAS was 41% (95% confidence interval [CI]: 36-48%). Median follow-up was 61 months. Median PFS was 20 (95% CI: 15-23) months; median overall survival (OS) was 63 (95% CI: 60-71) months. Cox regression analyses suggested improvement with first-line versus subsequent lines of FAS therapy. Main adverse events ≥ grade 3 were neutropenia (10%) and nausea/vomiting (5.5%). Dose reductions were required in 32% of patients. Post-FAS everolimus (n = 108; 68% second line) had a median PFS of 10 (95% CI: 8-14) months. Post-FAS temozolomide (n = 60; 53% ≥ fourth line) had an ORR of 13% and median PFS of 5.2 (95% CI: 4-12) months. In this largest reported cohort of PanNETs treated with chemotherapy, FAS demonstrated activity without significant safety concerns. FAS did not appear to affect subsequent PFS with everolimus; this sequence is being evaluated prospectively. Responses were noted with subsequent temozolomide-based regimens although PFS was possibly limited by line of therapy.

Development of the Functional Assessment of Cancer Therapy-Carcinoid Syndrome Symptom Index

OBJECTIVE

To develop a symptom-focused index to evaluate representative symptoms, treatment side effects, and emotional and functional well-being of patients with carcinoid syndrome (CS).

METHODS

The development of the Functional Assessment of Cancer Therapy-Carcinoid Syndrome Symptom Index (FACT-CSI) followed US Food and Drug Administration guidelines for the development of patient-reported outcome (PRO) measures and involved the following: (a) literature review; (b) interviews with 14 CS patients; (c) interviews with 9 clinicians; and (d) instrument development involving input from a range of PRO measure development and CS experts. The resulting draft instrument underwent cognitive interviews with 7 CS patients.

RESULTS

Forty-six CS sources were reviewed. Analysis of patient interviews produced 23 patient-reported symptoms. The most frequently endorsed physical symptoms were flushing, diarrhea, abdominal pain, fatigue, and food sensitivity/triggers. Seven priority CS emotional and functional themes were also identified by patients. Expert interviews revealed 12 unique priority symptoms - the most common being diarrhea, flushing, wheezing, edema, abdominal pain/cramping, fatigue, and 8 emotional and functional concerns. Through an iterative process of team and clinical collaborator meetings, data review, item reduction and measure revision, 24 items were selected for the draft symptom index representing symptoms, emotional concerns, global assessment of treatment side effects, and functional well-being. Cognitive interview results demonstrated strong content validity, including positive endorsement of item clarity (>86% across items), symptom relevance (>70% for most items), and overall measure content (86%).

CONCLUSIONS

The FACT-CSI is a content-relevant, symptom-focused index reflecting the highest priority and clinically relevant symptoms and concerns of people with CS.

Spartalizumab in metastatic, well/poorly-differentiated neuroendocrine neoplasms

Spartalizumab, a humanized anti-programmed death protein 1 (PD-1) monoclonal antibody, was evaluated in patients with well-differentiated metastatic grade 1/2 neuroendocrine tumors (NET) and poorly-differentiated gastroenteropancreatic neuroendocrine carcinomas (GEP-NEC). In this phase II, multicenter, single-arm study, patients received spartalizumab 400 mg every 4 weeks until confirmed disease progression or unacceptable toxicity. The primary endpoint was confirmed overall response rate (ORR) according to blinded independent review committee using response evaluation criteria in solid tumors 1.1. The study enrolled 95 patients in the NET group (30, 32 and 33 in the thoracic, gastrointestinal, and pancreatic cohorts, respectively), and 21 patients in the GEP-NEC group. The ORR was 7.4% (95% confidence interval [CI]: 3.0, 14.6) in the NET group (thoracic, 16.7%; gastrointestinal, 3.1%; pancreatic, 3.0%), which was below the predefined success criterion of ≥10%, and 4.8% (95% CI: 0.1, 23.8) in the GEP-NEC group. In the NET and GEP-NEC groups, the 12-month progression-free survival was 19.5% and 0%, respectively, and the 12-month overall survival was 73.5% and 19.1%, respectively. The ORR was higher in patients with ≥1% PD-L1 expression in immune/tumor cells or ≥1% CD8+ cells at baseline. The most common adverse events considered as spartalizumab-related included fatigue (29.5%) and nausea (10.5%) in the NET group, and increased aspartate and alanine aminotransferases (each 14.3%) in the GEP-NEC group. The efficacy of spartalizumab was limited in this heterogeneous and heavily pre-treated population; however, the results in the thoracic cohort is encouraging and warrants further investigation. Adverse events were manageable and consistent with previous experience.

Impact of Integrating Insulin-Like Growth Factor 1 Levels into Model for End-Stage Liver Disease Score for Survival Prediction in Hepatocellular Carcinoma Patients

BACKGROUND

Liver reserve affects survival in hepatocellular carcinoma (HCC). Model for End-Stage Liver Disease (MELD) score is used to predict overall survival (OS) and to prioritize HCC patients on the transplantation waiting list, but more accurate models are needed. We hypothesized that integrating insulin-like growth factor 1 (IGF-1) levels into MELD score (MELD-IGF-1) improves OS prediction as compared to MELD.

METHODS

We measured plasma IGF-1 levels in training (n = 310) and validation (n = 155) HCC cohorts and created MELD-IGF-1 score. Cox models were used to determine the association of MELD and MELD-IGF-1 with OS. Harrell's c-index was used to compare the predictive capacity.

RESULTS

IGF-1 was significantly associated with OS in both cohorts. Patients with an IGF-1 level of ≤26 ng/mL in the training cohort and in the validation cohorts had significantly higher hazard ratios than patients with the same MELD but IGF-1 >26 ng/mL. In both cohorts, MELD-IGF-1 scores had higher c-indices (0.60 and 0.66) than MELD scores (0.58 and 0.60) (p < 0.001 in both cohorts). Overall, 26% of training and 52.9% of validation cohort patients were reclassified into different risk groups by MELD-IGF-1 (p < 0.001).

CONCLUSIONS

After independent validation, the MELD-IGF-1 could be used to risk-stratify patients in clinical trials and for priority assignment for patients on liver transplantation waiting list.

IGF-Child-Turcotte-Pugh score as a predictor of treatment outcome in Child-Pugh A, advanced hepatocellular carcinoma patients undergoing sorafenib therapy

e16660

Background: Sorafenib is the first systemic therapy approved for advanced HCC treatment; with no accurate tool available to help predict survival and treatment outcome and to guide therapy decisions. Our novel blood-based insulin-like growth factor-1 (IGF)-Child-Turcotte-Pugh (CTP) score comprises levels of IGF-1, bilirubin, INR, and albumin. IGF-CP score significantly improved the prediction of HCC survival in our recently published studies. The current prospective study aimed to compare the overall survival (OS) and progression free survival (PFS) of 116 patients with CTP-A HCC treated with sorafenib whose score is reclassified as IGF-A (AA) to that of patients whose score is reclassified as IGF-B/C (AB/AC). Methods: After the approval of the institutional review boards and signing written informed consent, a total of 116 patients with HCC were prospectively enrolled and started on sorafenib and followed until progression or death. We calculated IGF-CTP scores, used Kaplan-Meier method and log rank test to estimate and compare time to event outcomes between subgroups of patients. Results: 116 patients were CTP class A, 87 of the patients with CTP class A were classified as IGF-CTP-A and had median OS of 13.16 ms (95% CI = 12.04 to 22.6 ms), and a median PFS of 5.82 months (ms) (95% CI = 4.34 to 9.14 ms), whereas 29 patients were reclassified as intermediate risk (IGF-CTP-B) and had had a higher risk of death with a shorter OS of 7.6 months (95% CI = 5.23 to 24.47 months) and shorter PFS of 3.49 months (95% CI = 2.53 to 5.26 months). There was higher overall rate of adverse events in the CTP-A patients reclassified as IGF-CTP B than IGF-CTP A especially in grade III-IV adverse events, upper GI Bleeding, lower GI Bleeding, nose bleeding, renal failure, liver failure, encephalopathy, fatigue, weight loss, anorexia, and vomiting. Conclusions: The results of this study support our biologically-driven hypothesis that among HCC patients with CTP-A class treated with sorafenib, those reclassified as IGF-CTP-B/C will have poorer prognosis in terms of shorter OS and PFS. Thus, our study provides an objective non-invasive strategy to better predict the outcome in HCC patients undergoing systemic therapy. Future validation of our IGF-1 score may lead to adopting it as a stratification tool in clinical trials as well as to predict HCC outcome and guide therapy decision in routine practice.

Financial burden of discarded weight-based cancer drugs to payers and patients in private insurance market

7083

Background: Studies assessing wastage of discarded weight (WT)-based cancer drugs (can-RX) derived their estimates from Medicare Average Sales Prices + 6% mark-up. With higher mark-ups, financial impact of discarded can-RX can be much higher in private insurance market. In addition, no study has examined the financial burden for patients(pts) even though they are subject to out-of-pocket payment (OOP) of the discarded RX. This study fills in these important knowledge gaps. Methods: We obtained the list of WT-based can-RX from the 2017 Centers for Medicare and Medicaid Services Part B Discarded Drug Units Report and gathered information on package size and recommended dose from IBM Micromedex. We identified pts who received WT-based can-RX from 2017 MarketScan data and linked to MarketScan Health Risk Assessment to obtain WT and height for a subset of pts. For each claim, we derived the recommended dose based on pt’s RX and his/her WT or body surface area (calculated from WT and height) and estimated the % of discarded dose. We quantified OOP as the sum of deductible, copayment, and coinsurance, and classified pts’ insurance by their enrollment to high-deductible (HD) plans. For claim-level analysis, we applied beta regression (for fractional outcomes) to determine factors associated with % discarded while accounting for within pts correlations. Covariates were age group (grp) ( < 50, 50-59, > = 60), WT grp ( < 150, 150-199, > = 200lb), HD plan (yes/no), region, cancer type, and can-RX. For pt-level analysis, we calculated the amount payers and pts spent on all and discarded can-RX in 2017 and compared OOP b/t pts in HD and non-HD plans. Results: Of 27,883 claims of WT-based can-RX, the median discarded % was 0.10 (mean 0.19, SD = 0.21). In addition to can-RX and cancer type, significantly higher discarded % was found in the lowest WT grp (0.03, P < 0.001, vs. WT > = 200lb) and significantly lower % was found in the middle age grp (-0.01, P = 0.02 vs. age < 50). Of 1963 pts, 778 (40%) had HD plans. Payments by payers (NETPAY) and pts (OOP) for total and discarded can-RX and the comparison b/t HD and non-HD plans are shown in Table. Conclusions: Payers incurred substantial financial burden from discarded can-RX. While OOP costs were modest for most privately insured pts, 5.3% of pts (~8% in HD plans) paid > $400 for discarded RX. [Table: see text]

Treatment outcome and prognostic indicators in 26 cases of fibrolamellar hepatocellular carcinoma under interferon based therapy

e16626

Background: Fibrolamellar hepatocellular carcinoma (FLHCC) is a variant of HCC that comprises ∼1%–9% of all HCCs, with about 200 annual cases reported globally, most often affects younger patients (10–35 years of age) with no underlying liver disease. There is no current standard of care therapy for unresectable FLHCC. We report an analysis of the treatment outcomes, and prognostic indicators of 26 cases. Methods: We retrospectively collected clinicopathologic and treatment outcome data from 26 FLHCC patients who received interferon alfa-2b (IFN) based therapy. Median overall survival (OS) and PFS were calculated using Kaplan-Meier curves, and survival rates were compared by the log-rank test. Results: 21 patient underwent treatment with continuous infusion (CI) 5-Fluorouracil (FU) at 200 mg/m2/day for 7 days on, 7 days off plus IFN at 4 million units/m2, subQ every other day for 7 days on, 7 days off, 1 patient FU+IFN+bevacizumab and 4 patients had PIAF (cisPlatin+IFN+Adriamycin+FU). Median age was 24 years (15-44), 13 males and 13 females, 8 of the 26 patients died, the median overall survival was 33.9 months (95% CI, 20.9, NA), estimated 3-year survival was 20.2% (95% CI: 4.1%, 98.5%), median follow up time was 13.4 months (95% CI: 9.79, NA) and median progression-free survival was 11.7 months (95% CI: 5.09, NA). The estimated 1-year survival was 47.9% (95% CI: 29.9%, 76.8%). Finally, FU+IFN combination was the most frequently used systemic therapy. 3/26 pts underwent surgical resection following neoadjuvant treatment with interferon based therapy; Interferon based therapy for the 26 patients had limited side effects, with only 3 of the 26 patients discontinued treatment due to grade 3-4 adverse event in the form of mucositis, severe fatigue and/or hematologic toxicity. Conclusions: Our analyses indicate that CI FU + IFN could be an effective treatment for FLHCC, and may have a neoadjuvant role in this disease with 3/26 were resectable following neoadjuvant treatment with interferon based therapy. This regimen can be well tolerated. Unfortunately, nonsurgical options for patients with FLC remain limited with no approved local or systemic therapies. Therefore, future research is needed to identify better multimodality therapies.

A phase II trial of atezolizumab and bevacizumab in patients with relapsed/refractory and unresectable malignant peritoneal mesothelioma

9013

Background: Malignant peritoneal mesothelioma (MPeM) is an orphan malignancy. No recommended/FDA approved therapies exist for salvage treatment beyond first-line platinum and pemetrexed based chemotherapy. While immune checkpoint inhibition has shown preliminary efficacy in mesotheliomas, data and efficacy is limited in MPeM patients (pts) [objective response rate (ORR) ~ 11%; median progression-free survival (mPFS) ~ 4 months (m); median overall survival (mOS) ~ 11 m]. We aimed to prospectively assess the safety and efficacy of combined anti-PD1 (atezolizumab) and VEGF (bevacizumab) blockade (AtezoBev) in pts with MPeM. Methods: In this phase 2 study, eligible pts with histologically confirmed MPeM, ECOG PS 0-1, and prior platinum and pemetrexed treatment were treated with 1200 mg of atezolizumab and 15 mg/kg of bevacizumab IV every 21 days until disease progression, unacceptable toxicity, or withdrawal. Primary endpoint was confirmed ORR by RECIST 1.1 by independent radiology review. Duration of response (DOR), PFS and OS were pre-specified secondary endpoints. Results: Among 20 enrolled pts (3/2017 - 2/2019), median age was 63 (range, 33-87) years, 12 (60%) were female, 12 (60%) had PS 0, and 2 (10%) had biphasic MPeM. Among 20 evaluable pts (median cycles 14), confirmed ORR was 35% (7 pts; 95% CI: 15.4-59.2) (median DOR 8.8 m). Responses were ongoing in 5/7 (71.4%) pts at data cutoff. The median follow-up was 20.5 months. Six deaths were observed during follow-up, and the 1-year OS was 79% (95% CI: 52 – 91) (median OS ~ NR). Median PFS was estimated as 17.6 m (95% CI: 9.1 – NR). The 1-year PFS was 54% (95% CI: 28 – 74). Grade 3 (no grade 4/5) treatment-emergent adverse events occurred in 10 (50%) pts; most common being hypertension (40%) and anemia (10%). Two (10%) pts had grade 3 immune-related adverse events. Translational studies are ongoing. Conclusions: AtezoBev showed promising and durable efficacy in relapsed/refractory MPeM with acceptable safety profile. Ongoing multiomic analyses of pre and on-treatment tissue/liquid biopsies obtained on all these pts will provide additional insight into mechanisms and biomarkers of response and resistance. Clinical trial information: NCT03074513.

Final results of a randomized, open label, perioperative phase II study evaluating nivolumab alone or nivolumab plus ipilimumab in patients with resectable HCC

4599

Background: In resectable hepatocellular carcinoma (HCC) surgical resection is associated with high recurrence rates. However, there is no approved neoadjuvant or adjuvant therapies yet. Neoadjuvant immunotherapy effect has never been reported in this setting in HCC. Methods: This is a randomized phase II trial of nivolumab (Arm A) or nivolumab + ipilimumab (Arm B) as peri-operative treatment for patients (pts) with HCC who are eligible for surgical resection. Pts in Arm A are given nivolumab 240 mg iv, every 2 weeks (wks) for a total of 3 doses followed by surgery on week 6. Pts in Arm B are treated with nivolumab per same schedule as arm A plus concurrent ipilimumab 1 mg/kg on day 1. Adjuvant part of study starts 4 weeks after surgery, with Nivolumab at 480 mg iv every 4 weeks for 2 years in arm A. Pts in Arm B are treated with nivolumab per same schedule as arm A plus concurrent ipilimumab 1 mg/kg every 6 weeks times 4 doses after resection. The primary objective was the safety/tolerability of nivolumab +/- ipilimumab. Secondary objectives include overall response rate, pathologic complete response (pCR) rate and time to progression. Exploratory objectives include evaluating the pre- and post-treatment immunological changes in tumor tissues and peripheral blood. Results: 30 patients were enrolled, 2 patients withdrew consent, one patient was not eligible at time of therapy, and 27 randomized (13 to Arm A and 14 to Arm B). 21 patients proceeded with resection as planned and surgery was aborted for 6 patients; 1 for frozen abdomen due to old surgery, 2 for small residual volume, and 3 for progressive disease. Pts age ranged between 32-83 yo, 75 % were males, 7 pts had HCV, 7 had HBV and 7 had no hepatitis. Pathologic complete response (pCR) was observed in 5/21 pts (24% pCR rate) – 2 in Arm A and 3 Arm B, and 3/21 pts (16%) – 1 in Arm A, 2 in Arm B, achieved major pathologic response (necrosis effect of 50-99%). 5 patients in Arm B and 1 in Arm A experienced grade 3 or higher toxicity prior to surgery. No grade 4 or higher toxicity were observed and surgery was not delayed or cancelled due to oxicity. Conclusions: Our study reached its primary endpoint of safety. Importantly, we report a 40% pathologic response rate = pCR rate of 24%, and major necrosis rate of 16% for resectable HCC after preoperative immunotherapy in a randomized phase II pilot trial. After future validation, these promising results may contribute to a paradigm shift in the perioperative treatment of resectable HCC. Clinical trial information: NCT03222076 .

The role of ALBI and IGF-CTP score in refining prognostication of HCC

e16659

Background: Child-Turcotte-Pugh (CTP) score is widely used in the assessment of prognosis of HCC and CTP-A is the standard criterion for active therapy and clinical trials entry. Recently, ALBI and insulin-like growth factor-1 (IGF)-CTP scores have been reported to improve survival prediction over CTP score. However, comparative studies to compare both scores and to integrate IGF into Albi score are lacking. Methods: After institutional board approval, data and samples were prospectively collected. 299 HCC patients who had data to generate both IGF-CPG and Albi index were used. The ALBI index, and IGF score were calculated, Cox proportional hazards models were fitted to evaluation the association between overall survival (OS) and CTP, IGF-CTP, Albi and IGF, albumin, bilirubin. Harrell’s Concordance index (C-index) was calculated to evaluate the ability of the three score system to predict overall survival. And the U-statistics was used to compare the performance of prediction of OS between the score system. Results: OS association with CTP, IGF-CTP and Albi was performed (Table). IGF-CTP B was associated with a higher risk of death than A (HR = 1.6087, 95% CI: 1.2039, 2.1497, p = 0.0013), ALBI grade 2 was also associated with a higher risk of death than 1 (HR = 2.2817, 95% CI: 1.7255, 3.0172, p < 0.0001). IGF-1(analyzed as categorical variable) was independently associated with OS after adjusting for the effects of ALBI grade. Which showed IGF-1 ≤26 was significantly associated with poor OS, P = 0.001. Conclusions: Although ALBI grade and IGF-CTP score in this analysis had similar prognostic values in most cases, their benefits might be heterogenous in some specific conditions. We looked into corporation of IGF-1 into ALBI grade, IGF score with cutoff ≤26 which clearly refined OS prediction and better OS stratification of ALBI-grade.

A phase II trial of atezolizumab and bevacizumab in patients with advanced, progressive neuroendocrine tumors (NETs)

619

Background: Neuroendocrine tumors (NETs) are relatively rare and heterogeneous tumors arising throughout the aerodigestive tract, which are incurable and life-limiting when metastatic. Prior studies of checkpoint inhibitors in NET patients have yielded minimal evidence of efficacy. Historically, effective therapies for advanced, progressive NET yield response rates less than 10% and progression-free survival (PFS) durations of approximately 11 months, as compared to approximately 4.5 months with placebo. Methods: We undertook a phase II basket study of atezolizumab in combination with bevacizumab in patients with rare cancers, and present here the data from the pancreatic NET (pNET) cohort and extrapancreatic NET (epNET) cohort, each of which included 20 patients with grade 1-2 NET that was progressive under any prior therapy. Patients received 1200mg of atezolizumab and 15mg/kg of bevacizumab IV q 21 days. The primary endpoint was confirmed objective response by RECIST 1.1. Results: The confirmed objective response rate with this combination was 20% (95% CI 6-44%) in the pNET cohort and 15% (95% CI 3-38%) in the epNET cohort. The median PFS in the pNET cohort is 19.6 months (95% CI 10.6-NR), while it was 14.9 months (95% CI 6.1-NR) in the epNET cohort, 1-year PFS was 75% and 52%, respectively. The combination was well-tolerated in this patient population, with the most common related treatment-emergent adverse events being hypertension (47.5%), proteinuria (37.5%), and fatigue (35%). The most common related grade 3/4 adverse events were hypertension (20%) and proteinuria (7.5%). Conclusions: The combination of atezolizumab and bevacizumab demonstrated moderate clinical activity in patients with advanced NETs. As pre-treatment and on-treatment biopsies were obtained for all patients, correlations with immune infiltration, mutations, and transcriptome alterations should provide additional insight into the mechanisms of response and resistance. Clinical trial information: NCT03074513.

Randomized, open-label, perioperative phase II study evaluating nivolumab alone or nivolumab plus ipilimumab in patients with resectable HCC

486

Background: In HCC, surgical resection is associated with high recurrence rates, and no effective neoadjuvant or adjuvant therapies currently exist. Immunotherapy using anti-PD-1 antibodies has shown promised but limited increase in survival in advanced disease. To maximize the benefit, we are studying the efficacy and safety of anti–PD-1 (nivolumab) and anti–CTLA-4 (ipilimumab) antibodies against HCC for resectable HCC. Methods: This is a randomized phase II trial of nivolumab (Arm A) or nivolumab + ipilimumab (Arm B) as pre-operative treatment for patients with HCC who are eligible for surgical resection. Pts are given nivolumab 240 mg every 2 weeks (wks) for a total of 6 wks. Pt in Arm B are treated concurrently with ipilimumab 1 mg/kg every 6 wks. Surgical resection occurs within 4 wks after last cycle of therapy. Pts continue adjuvant immunotherapy for up to 2 years after resection. The primary objective is the safety/tolerability of nivolumab +/- ipilimumab. Secondary objectives include overall response rate, complete response rate and time to progression. Exploratory objectives include evaluating the pre- and post-treatment immunological changes in tumor tissues and peripheral blood. Results: Twenty-six patients were enrolled at the time of this interim analysis, of which 20 have evaluable data. Most pts (55%) were between 60-70yo and male (75%). Four pts were HCV-positive, 6 had HBV and 10 had no hepatitis. 20 patients proceeded with resection as planned, surgery was aborted for 5 patients (1 for frozen abdomen and 2 development of contralateral liver nodule). Three are still receiving preoperative therapy. Pathologic complete response (pCR) was observed in 5/20 evaluable patients – 2 in Arm A and 3 Arm B (25% pCR rate). Five patients in Arm B and 1 in Arm A experienced grade 3 or higher toxicity prior to surgery. No grade 4 or higher toxicity were observed. Conclusions: We report a pCR rate of 25% for resectable HCC after preoperative immunotherapy in a randomized phase II pilot trial. Treatment was safe and surgical resection was not delayed. The study is ongoing. These promising results may contribute to a paradigm shift in the perioperative treatment of resectable HCC. Clinical trial information: NCT03510871.

Immune checkpoint blockade (ICB) response evaluation with MRI/MR elastography (MRE) in surgical and nonsurgical patients with HCC

480

Background: Currently, there is a lack of imaging biomarkers of immunotherapy outcome in hepatocellular carcinoma (HCC). The study aim was to determine if HCC enhancement on MRI and stiffness change measured by magnetic resonance elastography (MRE) can predict immunotherapy response. Methods: This was a prospective, Institutional Review Board approved study of 38 patients with HCC treated with immune checkpoint blockade (ICB) therapy. All patients had liver MRI/MRE and HCC biopsy at baseline, and MRI/MRE with biopsy or resection after 6 weeks therapy. HCC stiffness (kPa) was measured on MRE elastograms (liver stiffness maps). HCC enhancement and change in stiffness were compared with treatment response to ICB in 1) non-surgical patients (pembrolizumab), and 2) surgical patients (nivolumab +/- ipilimumab). For non-surgical patients, treatment response was defined as overall survival >1 year. For surgical patients, treatment response was defined as <50% viable tumor at time of resection. Analysis was performed using descriptive statistics and Spearman correlation; p-value <0.05 was considered statistically significant. Results: Twenty-five patients were evaluable. Median age was 67 years (32, 78). Etiology of liver disease was NASH (n=8), HCV (n=8), HBV (n=2) and unknown (n=7). Treatment response occurred in 11/25 (44%) patients. Median HCC size and change in size were 4.7 cm (1.2, 14.0) and –0.32 cm, respectively. Median baseline HCC stiffness and change in stiffness were 5 kPa (2.2, 12.4) and –0.1 kPa (–2.2, 1.5), respectively. Median change in HCC size for responders and non-responders was –1.2 cm (–4.8, 0.4) and 0 cm (–1.5, 1.1), respectively (p = 0.02). Treatment response was associated with absence of portal venous phase capsular enhancement and increase in HCC stiffness, (p<0.001). Conclusions: Capsular enhancement and MRE stiffness change may be useful biomarkers of immune cell activated response to ICB therapy.

IGF-1 Child-Turcotte-Pugh score as a predictor of overall survival to therapy in CTP-A, BCLC stage C patients with advanced hepatocellular carcinoma

488

Background: Child-Turcotte-Pugh (CTP) A is the standard population for active HCC therapy. The IGF-CTP score, comprises levels of type 1 insulin-like growth factor (IGF-1), bilirubin, INR, and albumin, significantly improved the prediction of overall survival (OS) in recently published studies. Our current study aimed to investigate the accuracy of the IGF-CTP score in predicting OS in HCC Child-Pugh A patients (pts) treated with local and/or systemic therapies (tx). The overall hypothesis is that the IGF-CTP score can further distinguish CP-A pts in terms of overall survival, PFS. Methods: Between 2014 and 2018, a total of 274 pts with new advanced HCC BCLC stage who had available baseline plasma IGF-1 level were retrospectively enrolled. Clinicopathologic features and treatment history were collected. We calculated IGF-CTP scores, used Kaplan-Meier method and log rank test to estimate and compare time to event outcomes between subgroups of patients. Results: 198 pts were CTP Class A, 209 patient underwent systemic tx, 65 underwent local tx [see table]; 161 were re-classified as IGF-CTP-A with a median OS of 16.09 months (95% CI = 13.06 to 23.29 months) (p <0.0001), whereas 37 patients were reclassified as intermediate risk (IGF-CTP-B) and had significantly shorter OS of 10.66 months (95% CI = 5.49 to 26.51) (p <0.0001). Conclusions: The results of this study support our biologically-driven hypothesis that IGF-CTP score is predictive of overall survival to therapy in advanced HCC treated with local and/or systemic therapy. Among HCC pts with CTP-A class, some are reclassified as IGF-CP-B/C and were found to have significantly poorer prognosis in terms of shorter OS. Future validation of the predictive ability of our IGF-1 score may lead to adopting it as a stratification tool in clinical trials as well as to predict HCC outcome and guide therapy decision in routine practice.

[Table: see text]

NCCN Guidelines Insights: Neuroendocrine and Adrenal Tumors, Version 2.2018

The NCCN Guidelines for Neuroendocrine and Adrenal Tumors provide recommendations for the management of adult patients with neuroendocrine tumors (NETs), adrenal gland tumors, pheochromocytomas, and paragangliomas. Management of NETs relies heavily on the site of the primary NET. These NCCN Guidelines Insights summarize the management options and the 2018 updates to the guidelines for locoregional advanced disease, and/or distant metastasis originating from gastrointestinal tract, bronchopulmonary, and thymus primary NETs.

Molecular Profiling of Hepatocellular Carcinoma Using Circulating Cell-Free DNA

PURPOSE

Molecular profiling has been used to select patients for targeted therapy and determine prognosis. Noninvasive strategies are critical to hepatocellular carcinoma (HCC) given the challenge of obtaining liver tissue biopsies.

EXPERIMENTAL DESIGN

We analyzed blood samples from 206 patients with HCC using comprehensive genomic testing (Guardant Health) of circulating tumor DNA (ctDNA).

RESULTS

A total of 153/206 (74.3%) were men; median age, 62 years (range, 18-91 years). A total of 181/206 patients had ≥1 alteration. The total number of alterations was 680 (nonunique); median number of alterations/patient was three (range, 1-13); median mutant allele frequency (% cfDNA), 0.49% (range, 0.06%-55.03%). TP53 was the common altered gene [>120 alterations (non-unique)] followed by EGFR, MET, ARID1A, MYC, NF1, BRAF, and ERBB2 [20-38 alterations (nonunique)/gene]. Of the patients with alterations, 56.9% (103/181) had ≥1 actionable alterations, most commonly in MYC, EGFR, ERBB2, BRAF, CCNE1, MET, PIK3CA, ARID1A, CDK6, and KRAS. In these genes, amplifications occurred more frequently than mutations. Hepatitis B (HBV)-positive patients were more likely to have ERBB2 alterations, 35.7% (5/14) versus 8.8% HBV-negative (P = 0.04).

CONCLUSIONS

This study represents the first large-scale analysis of blood-derived ctDNA in HCC in United States. The genomic distinction based on HCC risk factors and the high percentage of potentially actionable genomic alterations suggests potential clinical utility for this technology.