Background & Aims: We aimed to explore patient expectations regarding their treatments and prognosis in comparison physicians' assessments in patients with advanced hepatocellular carcinoma (HCC) receiving systemic treatments. Methods: We prospectively enrolled 205 patients in France and Belgium with Barcelona Clinic Liver Cancer (BCLC) stage B/C HCC receiving systemic treatment (NCT04823754). Patients completed a 28-question survey and the hospital anxiety and depression scale (HADS), while physicians filled a 17-question survey after the initial consultation. Univariate and multivariate models were used to assess factors associated with concordant patient-physician responses, HADS, as well as predicted (by physicians) and observed overall survival. Results: Patients had a median age of 68 years with 75% having BCLC C HCC; 86.3% received atezolizumab/bevacizumab. 60% of patients did not discuss life expectancy with the physician. 63% of the patients believed they had a life expectancy >5 years. Among shared questions between patients and physicians, 36.4% concordance was observed; major differences centered on life expectancy with patients more optimistic than physicians. A lower patient-physician concordance was seen with shorter consultations (p = 0.003), female physicians (p = 0.02), BCLC C (p = 0.03) and >100 HCC patients/year per physician (p 0.008). Compared to France, patients from Belgium were more likely to be satisfied with the consultation (p <0.001) but were less optimistic about life expectancy. Using HADS, 52% of the patients had anxiety/depression that was correlated with alphafetoprotein level (p = 0.03). The predicted median overall survival by physicians was 18 months vs. 13 months for the observed overall survival (weak correlation, q = 0.31). Conclusion: Expectations regarding systemic treatments for advanced HCC differ significantly between patients and physicians, showing notable variations across countries.

3596 Background: Surgical resection of CRLM aims to maximize patient survival. However, recurrence rates remain high post-surgery. We previously reported the prognostic relevance of tumor regression grading (TRG) and HGP of resected CRLM. Several studies reported the association of tumoral heterogeneity with anti-cancer drug resistance and prognosis. This study aims to explore tumoral heterogeneity for TRG and HGP in patients resected for CRLM and its prognostic implication. Methods: Tumor homogeneity for PR and HGP was evaluated in 2 independent cohorts. Cohort 1 included 57 patients (159 CRLMs) resected after chemotherapy/bevacizumab (prospective BEV-ONCO trial). Cohort 2 included 221 patients (582 CRLMs) operated after preoperative treatment or not. TRG (1 to 5 according complete to no response), HGP (desmoplastic, pushing, replacement or mixed) were evaluated for each CRLM. Max-TRG (higher TRG among all the CRLM) was used to define PR. Homogenous TRG (TRG-h) and HGP (HGP-h) was defined when all CRLMs had the same TRG or HGP pattern. HGP homogeneous desmoplastic (HGP-hd) was defined when all CRLM had a desmoplastic HGP. TRG-h, HGP-h and HGP-hd were combined into a homogeneity score (H-score: 0 to 3, 1 point given for each parameter and summed-up). Overall survival (OS for both cohorts), progression-free survival (PFS for cohort 1) and time to relapse (TTR for cohort 2) were estimated using the Kaplan–Meier method and compared by log-rank tests. Cox proportional hazard models were used for univariate and multivariate analyses. Results: Patient and disease characteristics were comparable in both cohorts excepted for preoperative treatment. In cohort 1, TRG-h and HGP-h were significantly associated with a longer PFS (HR = 0.21; 95CI:0.10-0.43, p < 0.001; HR = 0.27; 95CI = 0.14-0.54, p < 0.001) and better OS (HR = 0.23; 95CI = 0.07-0.70, p = 0.010; HR = 0.32; 95CI = 0.10-0.93, p = 0.037). Interestingly, the same significant results were observed in cohort 2 for TTR (TRG-h: HR = 0.60; 95CI = 0.43-0.85, p = 0.004; HGP-h: HR = 0.68; 95CI = 0.49-0.94, p = 0.017) and OS (TRG-h: HR = 0.51;95CI = 0.33-0.80, p = 0.003; HGP-h: HR = 0.63; 95CI = 0.41-0.97, p = 0.034). HGP-h reported a significant association with TRG-h, a Max-TRG < = 3, the absence of HGP replacement and mixed, a desmoplastic pattern, and the absence of sinusoidal obstruction syndrome in both cohorts. H-score was significantly associated with TTR (score 1-2: HR = 0.57; 95CI = 0.38-0.85, p = 0.004; score 3: HR = 0.4; 95CI = 0.24-0.64, p < 0.001) and OS (score 3: HR = 0.31; 95CI = 0.15-0.64, p < 0.001) in univariate analysis and with OS (HR = 0.74; 95CI = 0.59-0.94, p = 0.011) in multivariate analysis (cohort 2). Conclusions: TRG-h and HGP-h are strongly associated with patient’s survival. H-score could be an easy morphological and prognostic score to assess. Validation studies are needed.

Retrospective studies reported that preoperative oxaliplatin-based chemotherapy increased pathological response (PR) in patients resected for colorectal liver metastases (CRLM). This multicenter prospective randomized (1/1) phase II trial evaluated PR on resected CRLM after preoperative mFOLFOX6 (arm A) or FOLFIRI (arm B) + bevacizumab. The primary endpoint was the major pathological response rate (MPRR), defined as the percentage of patients presenting CRLMs with mean tumor regression grade (TRG) < 3. Secondary endpoints included safety, progression-free survival (PFS) and overall survival (OS). Out of 65 patients, 57 patients (28 and 29 in arm A/B) were resected for CRLM (one patient with lung metastases). Clinical and treatment characteristics were similar in both arms. One-month postoperative complications were 39.3%/31.0% in arm A/B (p = 0.585). MPRR and complete PR were 32.1%/20.7% (p = 0.379) and 14.3%/0.0% (p = 0.052) in arm A/B, respectively. PFS and OS were not different. Patients with PR among all CRLMs (max TRG ≤ 3; 43.8% of patients) had a lower risk of relapse (PFS: HR = 0.41, 95%CI = 0.204−0.840, p = 0.015) and a tendency towards better survival (OS: HR = 0.34, 95%CI = 0.104−1.114, p = 0.075). The homogeneity of PR was associated with improved PFS/OS. This trial fails to demonstrate a significant increase in MPRR in patients treated with mFOLFOX6-bevacizumab but confirms PR as an important prognostic factor.

3595 Background: Immune checkpoint inhibitors demonstrated poor efficacy in MSS mCRC. Cetuximab (anti-EGFR inhibitor) could initiate, independently from RAS mutation, an immunogenic tumor cell death and mediate antitumor immune response. In this trial, we aim to explore the clinical efficacy and safety of avelumab (anti-PDL1) combined with cetuximab and irinotecan for treatment refractory MSS mCRC and to understand its mechanisms of action through associated translational research. Methods: AVETUXIRI trial (NCT03608046) enrols MSS, chemorefractory (fluoropyrimidine, oxaliplatin, irinotecan and anti-EGFR treatment if RAS wt tumor) mCRC patients in 2 cohorts (A: RAS-wt, n = 10 – B: RAS-mut, n = 13). Primary endpoints are safety and tumor response rate ((i)RECIST1.1). Secondary endpoints include disease control rate (DCR), progression-free survival (PFS) and overall survival (OS). According to a Simon 2-stage design, 23 patients have been included in the first stage of the trial. Multiplex immunofluorescence and RNA sequencing were realized on metastasis biopsies performed before, during and after the treatment. Densities of CD3+ (T cells) and CD8+ (cytotoxic) were quantified and analyzed with to generate an immunoscore (IS). RNA-seq data was used to perform differential expression analysis (DESeq2), gene set enrichment analysis (GSEA), deconvolution analysis (ConsensusTME) and gene ontology analysis (GO). Results:: No unexpected safety signals were observed. 3/10 tumor responses were observed in cohort A, 0/13 in cohort B. DCR was 60.0% and 61.5% in cohort A and B, respectively. 6-months PFS and 12-months OS rates were respectively 40.0% and 50.0% (cohort A) and 38.5% and 46.2% (cohort B). Independently of RAS mutation, patients with a high IS (metastasis biopsy, baseline) had significantly higher tumor shrinkage (OR = 18.67 p = 0.019), median PFS (6.9 vs 3.4 months; HR = 0.16, p = 0.002) and median OS (13.7 vs 7.9 months, HR = 0.26, p = 0.009). Similarly, tumor shrinkage and survival outcome (PFS > 6 months, OS > 12 months) were associated with upregulation of an adaptive immune response signature (including Th1, chemokine, adhesion molecules, immune checkpoints and T-cell activation genes, p. adj = 0.009) and the GSEA hallmark of epithelial to mesenchymal transition (p. adj = 0.045). Few modifications of IS and gene expression profiles were observed on the different metastasis biopsies performed overtime in the included patients. Conclusions: AVETUXIRI met its preliminary primary efficacy endpoint for RAS-wt mCRC pts, justifying its current continuation. Encouraging survival data observed in RAS-mut cohort allow the opening of a new cohort (PFS as primary endpoint). IS and adaptive immune response signature evaluated on metastases biopsies were associated with treatment efficacy and survival. Clinical trial information: NCT03608046.

BACKGROUND:Sorafenib is the only systemic treatment that has shown a significant benefit in overall survival (OS) and in progression-free survival (PFS) in advanced hepatocellular carcinoma (HCC) patients. No standard of care currently exists for second-line treatment. The association of Gemcitabine-Oxaliplatine (GEMOX) has shown efficacy in the first-line setting. The aim of this study was to evaluate the efficacy of GEMOX after failure of at least one line of anti-angiogenic (AA) therapy.PATIENT AND METHODS:We performed a multicenter retrospective analysis of advanced HCC patients that received GEMOX chemotherapy after progression on at least one line of AA therapy.RESULTS:We analyzed a total of 40 patients that received a median of 7 cycles of GEMOX over a 6-year period. Grade 3/4 toxicity was observed in 25 % of patients, mainly neurotoxicity, thrombocytopenia and neutropenia in 12.5 %, 5 % and 5 % of patients respectively. Grade <3 toxicity was mainly hematological and neurotoxicity. In the sub-cohort of 35 patients evaluable for response, partial response was observed in 20 % of patients, while 46 % had stable disease. Median OS was 8.3 months, with a 6-month OS rate of 59 %. Median PFS was 3.1 months. Prognostic factors for OS in univariable analysis were the performance status and AFP levels at GEMOX start, and the BCLC score at diagnosis. None of these factors were prognostic for PFS or tumor response.CONCLUSION:The GEMOX schedule seems to show clinical activity and an acceptable toxicity profile in advanced HCC patients who progressed after anti-angiogenic treatment. The observed median OS of over 8 months is encouraging in this population of heavily pretreated patients. These results would merit confirmation in a prospective randomized study.

ABSTRACT Introduction This retrospective review evaluates the efficacy and safety of m FOLFIRI in patients with AGC who failed chemotherapy including both fluoropyrimidine and platinum. Methods Patients (pts) with locally advanced or metastatic disease, histologically documented AGC who failed one prior chemotherapy, ECOG PS≤2, at least 1 measurable lesion, were treated with mFOLFIRI every 2 weeks. Treatment protocol included: Irinotecan: 180 mg/m2 over 90 mn, LV: 40 mg/m2 then bolus 5FU: 400 mg/m2 Day1, followed by 2400 mg/m2 CI over 46 hours. Prior chemotherapy: EOX: 9 FOLFOX: 9; ECX: 6; LV5FU2 CDDP: 12; other: 7. Primary objectives were toxicity, PFS and OS rate. Results A total of 43 pts were treated. Median age: 59 (28-74), male: 26 (60%); ECOG 0+1: 60%; 2: 40%. Site of disease: liver in 16 (37%), peritoneal in 24 (56%); lung/pleural in 11 (26%); lymph-nodes in 11 (26 %). Isolated metastatic site in 32%, multiple sites in 68%.The main toxicities were grade 2 diarrhea (12%); grade 3 neutropenia (7%); anemia: 7%; asthenia: 7%; stroke: 1. A total of 410 cycles were administered with a median of 8 cycles (range, 2-34). One patient (2 %) achieved confirmed partial response and 34 patients (79%) showed stable disease, resulting in a disease control rate of 81%. Median PFS time was 3.6 months (95% CI: 2.1- 4.9 months); median OS time was 7.8months (95% CI: 4.2 -9.9 months). Conclusion The current mFOLFIRI showed a high PFS and OS with an acceptable toxicity profile in patients with AGC and could be a valid second line option in selected cases.