Prognostic and predictive impact of sex in locally advanced microsatellite instability high gastric or gastroesophageal junction cancer: An individual patient data pooled analysis of randomized clinical trials

BACKGROUND

Surgery plus peri-operative/adjuvant chemotherapy is the standard of care for locally advanced GC/GEJC, though with unsatisfactory results. dMMR/MSI-high tumors have better prognosis and scant benefit from chemotherapy as compared to pMMR/MSS ones. The differential outcome of therapies in terms of safety and efficacy according to sex is still debated in GC/GEJC patients.

METHODS

We previously performed an individual patient data pooled analysis of MAGIC, CLASSIC, ITACA-S, and ARTIST trials including GC/GEJC patients treated with surgery alone or surgery plus peri-operative/adjuvant chemotherapy to assess the value of MSI status. We performed a secondary analysis investigating the prognostic and predictive role of sex (female versus male) in the pooled analysis dataset in the overall population and patients stratified for MSI status (MSI-high versus MSS/MSI-low). Disease-free (DFS) and overall survival (OS) were calculated.

RESULTS

Patients with MSI-high tumors had improved survival as compared to MSS/MSI-low ones irrespective of sex, whereas in those with MSS/MSI-low tumors, females had numerically longer OS and DFS (5-year OS was 63.2% versus 57.6%, HR 0.842; p = 0.058, and 5-year DFS was 55.8% versus 50.8%, HR 0.850; p = 0.0504 in female versus male patients). The numerical difference for the detrimental effect of chemotherapy in MSI-high GC was higher in females than males, while the significant benefit of chemotherapy over surgery alone was confirmed in MSS/MSI-low GC irrespective of sex.

CONCLUSIONS

This pooled analysis including four randomized trials highlights a relevant impact of sex in the prognosis and treatment efficacy of MSI-high and MSS/MSI-low non-metastatic GC/GEJC.

Early immune remodeling steers clinical response to frontline chemoimmunotherapy in advanced gastric cancer

Adding anti-PD1 to 5-FU/platinum improves survival in some advanced gastroesophageal adenocarcinomas (GEA). To understand the effects of chemotherapy and immunotherapy we conducted a phase II frontline trial (n = 47) sequentially adding pembrolizumab to 5-FU/platinum in advanced GEA. Using serial biopsy of the primary tumor at baseline, after one cycle of 5-FU/platinum, and after the addition of pembrolizumab we transcriptionally profiled 358,067 single cells to identify evolving multicellular TME networks. Chemotherapy induced early on-treatment multicellular hubs with tumor-reactive T-cell and M1-like macrophage interactions in slow progressors. Faster progression featured increased MUC5A and MSLN containing treatment-resistance programs in tumor cells and M2-like macrophages with immunosuppressive stromal interactions. After pembrolizumab we observed increased CD8 T-cell infiltration and development of an immunity hub involving tumor-reactive CXCL13 T-cell program and epithelial interferon-stimulated gene programs. Strategies to drive increases in anti-tumor immune hub formation could expand the portion of patients benefiting from anti-PD1 approaches.

Effect of ramucirumab plus paclitaxel in advanced gastric cancer according to the status of programmed cell death-ligand 1 (PD-L1) expression

Background

Ramucirumab, an anti-vascular endothelial growth factor receptor (VEGFR) monoclonal antibody (mAb), inhibits angiogenesis and reduces tumor activity. Programmed cell death-ligand 1 (PD-L1) might act upon VEGFR2 to induce cancer cell angiogenesis and metastasis. Herein, we investigated the efficacy of combining ramucirumab and paclitaxel according to the status of PD-L1 expression in patients with advanced gastric cancer (AGC).

Methods

This analysis included AGC patients who received ramucirumab plus paclitaxel as 2nd line therapy between December 1, 2018, and February 28, 2022, at Samsung Medical Center. All patient data analyses included an evaluation of PD-L1 expression using the combined positive score (CPS). We analyzed the efficacy and the survival of patients according to their PD-L1 expression.

Results

We included 117 patients in this analysis, and 80 patients (68.4%) had a PD-L1 CPS of one or more, 37 (31.6%) had five or more, and 19 (16.2%) had ten or more scores. Progression-free survival (PFS) and overall survival (OS) did not differ significantly between patients with a PD-L1 CPS of less than one and one or more {PD-L1 <1% vs. PD-L1 ≥1%; PFS: median 3.6 months [95% confidence interval (CI): 2.4-4.8 months] vs. median 4.1 months (95% CI: 3.5-4.7 months), P=0.93; PD-L1 <1% vs. PD-L1 ≥1%; OS: median 7.0 months (95% CI: 5.4-8.6 months) vs. median 8.1 months (95% CI: 6.4-9.8 months), P=0.32}. PFS and OS did not differ significantly between patients with a PD-L1 CPS of less than 5 and 5 or more [PD-L1 <5% vs. PD-L1 ≥5%; PFS: 3.9 months (95% CI: 3.3-4.5 months) vs. 4.4 months (95% CI: 3.0-5.8 months), P=0.57; OS: 7.4 months (95% CI: 6.5-8.3 months) vs. 10.0 months (95% CI: 1.1-18.9 months), P=0.07]. Interestingly, with a PD-L1 CPS cutoff of 10, PFS and OS did differ significantly [PD-L1 <10% vs. PD-L1 ≥10%; PFS: 3.8 months (95% CI: 3.3-4.3 months) vs. 5.7 months (95% CI: 4.1-7.3 months), P=0.05; OS: 7.2 months (95% CI: 6.5-7.9 months) vs. 18.9 months (95% CI: 6.5-31.3 months), P=0.04].

Conclusions

No biomarkers have been established to predict survival times after ramucirumab plus paclitaxel treatment. This analysis suggests that a PD-L1 CPS cutoff of 10 might be novel a biomarker to predict the survival of AGC patients treated with ramucirumab and paclitaxel.

The role of ramucirumab plus paclitaxel as second-line therapy after failure of nivolumab plus doublet chemotherapy in patients with advanced gastric cancer

Background

Adding nivolumab to fluoropyrimidines and platinum agents has been considered a new standard first-line treatment in previously untreated human epidermal growth factor receptor 2 (HER2)-negative advanced gastric cancer (AGC). However, there were few data on the role of ramucirumab plus paclitaxel as second-line treatment after failure of nivolumab plus doublet chemotherapy. Herein, we analyzed the efficacy and safety of second-line ramucirumab plus paclitaxel in AGC patients refractory to nivolumab plus chemotherapy.

Methods

This analysis included AGC patients with ramucirumab plus paclitaxel as second-line therapy after failing to respond to nivolumab plus doublet chemotherapy [capecitabine plus oxaliplatin (XELOX) or 5-fluorouracil plus oxaliplatin (FOLFOX)] at Samsung Medical Center, Korea. Twenty patients who progressed on nivolumab plus chemotherapy as first-line therapy were treated with ramucirumab plus paclitaxel between December 2021 and September 2022.

Results

The median age was 56 (range, 24-76) years, and 13 (65.0%) were men. Of the 20 patients, 15 (75.0%) patients received nivolumab plus capecitabine, and oxaliplatin, while 5 (25.0%) patients received nivolumab plus 5-fluorouracil, and oxaliplatin. Two showed a partial response (PR) to ramucirumab plus paclitaxel, a response rate of 10%. Patients with stable disease (SD) accounted for a disease control rate (DCR) of 55.0%. The median progression-free survival (PFS) to ramucirumab plus paclitaxel was 2.7 months [95% confidence interval (CI): 1.7-3.7]. Subgroup analysis showed that responders (n=7) to first-line therapy had a PFS of 6.9 months compared to 2.3 months in non-responders (n=13) to first-line therapy. The median overall survival (OS) was 6.3 months (95% CI: 5.5-8.3), representing 6.9 months (95% CI: not calculated) in responders and 6.3 months (95% CI: 3.7-8.9) in non-responders (P=0.401).

Conclusions

This analysis suggested that ramucirumab plus paclitaxel as second-line therapy might be further studied in AGC patients after failure of nivolumab plus chemotherapy. A new second-line therapy is needed in AGC patients after nivolumab plus chemotherapy.

Patient-derived exosomes facilitate therapeutic targeting of oncogenic MET in advanced gastric cancer

Gastric cancer (GC) with peritoneal metastases and malignant ascites continues to have poor prognosis. Exosomes mediate intercellular communication during cancer progression and promote therapeutic resistance. Here, we report the significance of exosomes derived from malignant ascites (EXOAscites) in cancer progression and use modified exosomes as resources for cancer therapy. EXOAscites from patients with GC stimulated invasiveness and angiogenesis in an ex vivo three-dimensional autologous tumor spheroid microfluidic system. EXOAscites concentration increased invasiveness, and blockade of their secretion suppressed tumor progression. In MET-amplified GC, EXOAscites contain abundant MET; their selective delivery to tumor cells enhanced angiogenesis and invasiveness. Exosomal MET depletion substantially reduced invasiveness; an additive therapeutic effect was induced when combined with MET and/or VEGFR2 inhibition in a patient-derived MET-amplified GC model. Allogeneic MET-harboring exosome delivery induced invasion and angiogenesis in a MET non-amplified GC model. MET-amplified patient tissues showed higher exosome concentration than their adjacent normal tissues. Manipulating exosome content and production may be a promising complementary strategy against GC.

Impact of programmed death-ligand 1 (PD-L1) positivity on clinical and molecular features of patients with metastatic gastric cancer

BACKGROUND

Programmed death-ligand 1 (PD-L1) is an important screening biomarker to select patients with gastric cancer (GC) for optimized treatment, including immune checkpoint inhibitors (ICI).

METHODS

In this single-institution retrospective cohort study, patients with metastatic GC with available PD-L1 results between October 2019 and September 2021 were identified by reviewing their electronic medical records. Genomic data were obtained from the Samsung Medical Center Clinical Sequencing Platform.

RESULTS

Among the 399 patients, 276 (69%) had a PD-L1 combined positive score (CPS) ≥1, 155 (39%) had a CPS between 1 and 5, and 121 (30%) had a CPS ≥5. Of the 121 patients with CPS ≥5, 28 (23%) had a known etiology for "inflamed tumor," with Epstein-Barr virus (EBV) positivity (N = 11) or high tumor mutational burden (TMB) (N = 17), which included microsatellite instability (MSI) (N = 9). PD-L1 CPS ≥5 was observed in 11/11 (100%) patients with EBV positivity, 9/12 (75%) patients with MSI, and 17/33 (52%) patients with high TMB. For the 108 patients who received ICI therapy, CPS ≥5 was the only predictor significantly associated with survival in multivariable analyses, including TMB, MSI, or EBV. Objective response rate (ORR) was 49% in patients with CPS ≥5, 30% in patients with 1 ≤ CPS <5, and 19% in patients with CPS <1. Among the 31 responders to ICI therapy, 27 (87%) had a CPS of ≥1. Mutations in TET2, IRS2, DOT1L, PTPRT, and LRP1B were associated with a higher ORR (63%-100%), whereas MDC1 mutations were associated with a low ORR (22%).

CONCLUSIONS

PD-L1 expression is an independent and sensitive biomarker for ICI therapy. Considering its significant association with several gene alterations, including PIK3CA mutations and MET amplification, combining ICI therapy with other targeted agents may be a promising therapeutic strategy for GC.

The Optimal Tumor Mutational Burden Cutoff Value as a Novel Marker for Predicting the Efficacy of Programmed Cell Death-1 Checkpoint Inhibitors in Advanced Gastric Cancer

PURPOSE

The optimal tumor mutational burden (TMB) value for predicting treatment response to programmed cell death-1 (PD-1) checkpoint inhibitors in advanced gastric cancer (AGC) remains unclear. We aimed to investigate the optimal TMB cutoff value that could predict the efficacy of PD-1 checkpoint inhibitors in AGC.

MATERIALS AND METHODS

Patients with AGC who received pembrolizumab or nivolumab between October 1, 2020, and July 27, 2021, at Samsung Medical Center in Korea were retrospectively analyzed. The TMB levels were measured using a next-generation sequencing assay. Based on receiver operating characteristic curve analysis, the TMB cutoff value was determined.

RESULTS

A total 53 patients were analyzed. The TMB cutoff value for predicting the overall response rate (ORR) to PD-1 checkpoint inhibitors was defined as 13.31 mutations per megabase (mt/Mb) with 56% sensitivity and 95% specificity. Based on this definition, 7 (13.2%) patients were TMB-high (TMB-H). The ORR differed between the TMB-low (TMB-L) and TMB-H (8.7% vs. 71.4%, P=0.001). The progression-free survival and overall survival (OS) for 53 patients were 1.93 (95% confidence interval [CI], 1.600-2.268) and 4.26 months (95% CI, 2.992-5.532). The median OS was longer in the TMB-H (20.8 months; 95% CI, 2.292-39.281) than in the TMB-L (3.31 months; 95% CI, 1.604-5.019; P=0.049).

CONCLUSIONS

The TMB cutoff value for predicting treatment response in AGC patients who received PD-1 checkpoint inhibitor monotherapy as salvage treatment was 13.31 mt/Mb. When applying the programmed death ligand-1 status to TMB-H, patients who would benefit from PD-1 checkpoint inhibitors can be selected.

Phase I study of Minnelide and paclitaxel combination chemotherapy in refractory gastric cancer (GC)

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Background: Minnelide is a prodrug that rapidly releases the active compound triptolide when exposed to phosphatases in the bloodstream. Triptolide is a diterpene that has been shown to inhibit tumor cell proliferation and induce apoptosis in various cancer types. The anti-tumor effect of triptolide is the result of inhibition of heat shock protein (HSP) 70 expression. In GC Minnelide inhibits Sp1 to decrease HSP70 and induce cell death in preclinical data. Methods: This phase 1 trial was designed to determine the maximum tolerated dose (MTD) of Minnelide monotherapy and the MTD of Minnelide in combination with paclitaxel in refractory GC patients. There were 6 cohorts tested in this trial: cohort A: Minnelide 1 mg qd D1-21, q 28 days; cohort B: Minnelide 1.25 mg qd D1-21, q 28 days; cohort C: 1.5 mg qd D1-21, q 28 days; cohort D: Minnelide 0.25 mg D1-21 + weekly paclitaxel 60 mg/m2 on D1, D8, D15; cohort E: Minnelide 0.5 mg qd D1-21+ weekly paclitaxel 80 mg/m2 on D1, D8, D15; cohort F: Minnelide 0.75 mg qd D1-21+ weekly paclitaxel 80 mg/m2 D1, D8, D15. Results: From Feb 2021 to Sep 2022, 23 GC patients were enrolled (cohort A – C, N=10; cohort D-F, N=12). All patients had metastatic disease at the time of study enrollment. 20 of 23 patients received the study treatment as >= 3rd-line (range, 2 – 6th line). In all, 3 patients had HER2 positive GC and 10 patients had PDL1 + tumor. In the monotherapy cohorts, there were no DLTs observed, and the regimen was tolerated well. One patient achieved confirmed PR which lasted for 6 months. For the combination arm (cohort D-F), there were no DLTs observed. Of the 11 patients who were evaluable for treatment response, there were 1 PR, 5 SDs and 5 PDs. Two of five patients who achieved stable disease had durable stable disease for > 6 months on study treatment. In the combination cohorts, the most common adverse events of any grade were neutropenia; however, there was no neutropenic fever or treatment related mortality. Conclusions: Minnelide in combination with weekly paclitaxel demonstrated promising anti-tumor activity with durable responses in refractory AGC. Clinical trial information: Underreview .

A Phase II Study of Preoperative Chemoradiotherapy with Capecitabine Plus Simvastatin in Patients with Locally Advanced Rectal Cancer

PURPOSE

The purpose of this phase II trial was to evaluate whether the addition of simvastatin, a synthetic 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor, to preoperative chemoradiotherapy (CRT) with capecitabine confers a clinical benefit to patients with locally advanced rectal cancer (LARC).

MATERIALS AND METHODS

Patients with LARC (defined by clinical stage T3/4 and/or lymph node positivity) received preoperative radiation (45-50.4 Gy in 25-28 daily fractions) with concomitant capecitabine (825 mg/m2 twice per day) and simvastatin (80 mg, daily). Curative surgery was planned 4-8 weeks after completion of the CRT regimen. The primary endpoint was pathologic complete response (pCR). The secondary endpoints included sphincter-sparing surgery, R0 resection, disease-free survival, overall survival, the pattern of failure, and toxicity.

RESULTS

Between October 2014 and July 2017, 61 patients were enrolled; 53 patients completed CRT regimen and underwent total mesorectal excision. The pCR rate was 18.9% (n=10) by per-protocol analysis. Sphincter-sparing surgery was performed in 51 patients (96.2%). R0 resection was achieved in 51 patients (96.2%). One patient experienced grade 3 liver enzyme elevation. No patient experienced additional toxicity caused by simvastatin.

CONCLUSION

The combination of 80 mg simvastatin with CRT and capecitabine did not improve pCR in patients with LARC, although it did not increase toxicity.

Randomized phase II study of capecitabine plus cisplatin with or without sorafenib in patients with metastatic gastric cancer (STARGATE)

BACKGROUND

In this randomized phase II study, we evaluated the efficacy and safety of sorafenib in combination with capecitabine and cisplatin (XP) as first-line chemotherapy in advanced gastric cancer.

PATIENTS AND METHODS

Patients with metastatic gastric or gastroesophageal junction adenocarcinoma were randomized (1:1) to receive either sorafenib plus XP (S + XP) or XP alone. In cases of disease progression in the XP arm, crossover to sorafenib alone was allowed. The primary endpoint was progression-free survival (PFS). The secondary endpoints included overall survival (OS), response rates, safety profiles, and biomarkers, and the response rates and PFS with secondline sorafenib alone after progression in the XP arm.

RESULTS

Between Jan 2011 and Feb 2013, a total of 195 patients were accrued (97 in the S + XP arm and 98 in the XP alone arm). The overall response rate was 54% with S + XP, and 52% with XP alone (p = 0.83). With a median follow-up of 12.6 months (range, 0.1-29.2), the median PFS assessed by independent review was 5.6 months in the S + XP arm and 5.3 months in the XP arm (hazard ratio [HR] 0.92, 95% confidence interval [CI] 0.67-1.27, p = 0.61). Overall survival was not different between the two arms (median 11.7 vs. 10.8 months; HR 0.93, 95% CI 0.65-1.31, p = 0.66). Frequencies of grade 3/4 toxicities were similar between the S + XP and XP alone arms, except for neutropenia (21% vs. 37%), anorexia (0% vs. 5%), and hand-foot skin reaction (7% vs. 1%). Among 51 patients who crossed over to sorafenib alone after disease progression in the XP arm, there was no objective response and their median PFS was 1.3 months (95% CI, 1.2-1.7).

CONCLUSION

The addition of sorafenib to XP chemotherapy was safe but not more effective than XP alone for first-line treatment of metastatic gastric cancer.

MET gene alterations predict poor survival following chemotherapy in patients with advanced cancer

Background: To aid in oncology drug development, we investigated MET proto-oncogene receptor tyrosine kinase gene aberrations in 2,239 oncology patients who underwent next-generation sequencing (NGS) in clinical practice. Materials and methods: From November 2019 to January 2021, 2,239 patientswith advanced solid tumors who visited oncology clinics underwent NGS. The NGS panel included >500 comprehensive NGS tests using archival tissue specimens. Programmed death-ligand 1(PD-L1) 22C3 assay results and clinical records regarding initial chemotherapy were available for 1,137 (50.8%) and 1,761 (78.7%) patients, respectively for overall survival (OS) analysis. Results: The 2,239 patients represented 37 types of cancer. The NGS panel included >500 genes, microsatellite instability status, tumor mutational burden, and fusions. The most common cancer types were colorectal (N = 702), gastric (N = 481), and sarcoma (N = 180). MET aberrations were detected in 212 patients. All MET-amplified tumors had microsatellite stable status, and 8 had a high tumor mutational burden. Of 46 patients with MET-amplified cancers, 8 had MET-positive protein expression by immunohistochemistry (2+ and 3+). MET fusion was detected in 10 patients. Partner genes of MET fusion included ST7, TFEC, LRRD1, CFTR, CAV1, PCM1, HLA-DRB1, and CAPZA2. In survival analysis, patients with amplification of MET gene fusion had shorter OS and progression-free survival (PFS) than those without. Thus, MET aberration was determined to be a factor of response to chemotherapy. Conclusion: Approximately 2.1% and 0.4% of patients with advanced solid tumors demonstrated MET gene amplification and fusion, respectively, and displayed a worse response to chemotherapy and significantly shorter OS and PFS than those without MET gene amplification or fusion.

Phase II study of ceralasertib (AZD6738) in combination with durvalumab in patients with advanced gastric cancer

BACKGROUND

Targeting the DNA damage repair (DDR) pathways is an attractive strategy for boosting cancer immunotherapy. Ceralasertib (AZD6738) is an oral kinase inhibitor of ataxia telangiectasia and Rad3 related protein, which is a master regulator of DDR. We conducted a phase II trial of ceralasertib plus durvalumab in patients with previously treated advanced gastric cancer (AGC) to demonstrate the safety, tolerability, and clinical activity of the combination.

METHODS

This phase II, open-label, single-center, non-randomized study was designed to evaluate the efficacy and safety of ceralasertib in combination with durvalumab in patients with AGC. The study drug regimen was ceralasertib (240 mg two times a day) days 15-28 in a 28-day cycle in combination with durvalumab (1500 mg) at day 1 every 4 weeks. The primary end point was overall response rate (ORR) by Response Evaluation Criteria in Solid Tumors (V.1.1). Exploratory biomarker analysis was performed using fresh tumor biopsies in all enrolled patients.

RESULTS

Among 31 patients, the ORR, disease control rate, median progression-free survival (PFS), and overall survival were 22.6% (95% CI 9.6% to 41.1%), 58.1% (95% CI 39.1% to 75.5%), 3.0 (95% CI 2.1 to 3.9) months, and 6.7 (95% CI 3.8 to 9.6) months, respectively. Common adverse events were manageable with dose modification. A subgroup of patients with a loss of ataxia telangiectasia mutated (ATM) expression and/or high proportion of mutational signature attributable to homologous repair deficiency (sig. HRD) demonstrated a significantly longer PFS than those with intact ATM and low sig. HRD (5.60 vs 1.65 months; HR 0.13, 95% CI 0.045 to 0.39; long-rank p<0.001). During the study treatment, upregulation of the innate immune response by cytosolic DNA, activation of intratumoral lymphocytes, and expansion of circulating tumor-reactive CD8 +T cell clones were identified in responders. Enrichment of the tumor vasculature signature was associated with treatment resistance.

CONCLUSIONS

Ceralasertib plus durvalumab has promising antitumor activity, with durable responses in patients with refractory AGC. Thus, a biomarker-driven trial is required.

TRIAL REGISTRATION

NCT03780608.

Clinical Significance of Preoperative Hematological Parameters in Patients with D2-Resected, Node-Positive Stomach Cancer

The purpose of the present study was to investigate the clinical significance of preoperative hematological parameters in patients with advanced stomach cancer, and to explore who might benefit from adjuvant concurrent chemoradiotherapy (CCRT) compared to chemotherapy alone. Among 1032 patients with node-positive stomach cancer who had a confirmed diagnosis after complete D2 resection, and who received adjuvant chemotherapy alone or CCRT, a total of 692 patients was selected using propensity score matching. Among absolute neutrophil count, absolute lymphocyte count (ALC), absolute monocyte count (AMC), platelet count, neutrophil-to-lymphocyte ratio, lymphocyte-to-monocyte ratio, and platelet-to-lymphocyte ratio, AMC was the most relevant prognostic factor for overall survival and recurrence-free survival (hazard ratio (HR) 1.674, 95% confidence interval (CI) 1.180–2.376; HR 1.908, 95% CI 1.650–2.695, respectively). In a subgroup with a high ALC, patients treated with adjuvant CCRT had a favorable recurrence-free survival (HR 0.620, 95% CI 0.393–0.980) compared to those treated with chemotherapy alone. Further study is needed to confirm our findings and to develop tailored adjuvant treatment.

Phase II study of ceralasertib (AZD6738) in combination with durvalumab in patients with advanced gastric cancer

4045

Background: Alterations in DNA damage response (DDR) and repair are associated with genomic instability and increased somatic tumor mutational burden, and modulating DNA repair using specific inhibitors is a promising strategy to boost the efficacy of cancer immunotherapy. Ceralasertib is an oral inhibitor of the serine/threonine protein kinase Ataxia Telangiectasia and Rad3 Related (ATR), which is crucial to the cell’s response to replication stress. Methods: This phase 2 trial was designed to evaluate the efficacy and safety of ceralasertib in combination with durvalumab in patients with advanced gastric cancer (AGC). The study drug regimen was ceralasertib 240 mg BD days 15 to 28 in a 28-day cycle in combination with durvalumab at 1500 mg day 1 every 4 weeks. The primary end point was overall response rate (ORR) by RECIST (v1.1). Exploratory biomarker analysis was performed using fresh tumor biopsies in all enrolled patients. Results: 31 patients (median no. of prior lines, 2; range, 2-5) were enrolled between Jul 2019 and Mar 2020. All enrolled patients had confirmed microsatellite stable tumors, 5 patients were EBV positive, and 24 patients were PD-L1 positive (CPS≥1). Two patients had received prior anti-PD-1 treatment. At the time of data cut-off (Dec 2020), 30 patients were evaluable for response: 7 partial responses (one patient with prior anti-PD-1 treatment), 11 stable disease, and 12 disease progression were observed. The ORR was 22.6%, DCR 58.1 %, median PFS 3.0 months (95% confidence interval (CI), 2.1-3.9), median duration of response 5.7 months (95% CI, 4.9-6.5), and median OS was 6.7 months (95% CI, 3.8-9.6). A subgroup of patients (n = 11) who with loss of ATM expression and/or high proportion of mutational signature attributable to homologous repair deficiency (sig. HRD) demonstrated significantly longer PFS than those (n = 12) who had intact ATM and low sig. HRD (5.60 vs 1.65 months, hazard ratio 0.13, 95% CI 0.045-0.39, long-rank P < 0.001). The most common adverse events of any grade were fatigue (n = 22, 71.0%), nausea (n = 20, 64.5%) and anorexia (n = 19, 61.3%), and the most common adverse events of grade 3 or more were anemia and thrombocytopenia (n = 11, 35.5% each). Conclusions: Ceralasertib in combination with durvalumab demonstrated promising anti-tumor activity with durable responses in refractory AGC. Clinical trial information: NCT03780608.

Tumor microenvironment (TME) dynamics following capecitabine/oxaliplatin (CapeOx) plus pembrolizumab in patients with advanced gastric cancer

4053

Background: Immune checkpoint inhibition (ICI) has made significant breakthroughs in several tumor types including gastric cancer (GC) in recent years. However, single-agent pembrolizumab demonstrated remarkable and durable response in MSI and EBV GC because they are immune-enriched types. Recently, we reported on-treatment remodeling of the TME during chemotherapy in MSS AGC ( Cancer Discov. 2021). We defined altered features including decreased tumor-associated macrophages (TAM), M1- macrophages repolarization and recruitment of NK cells, effector T cells. Methods: This phase 2, open-label, single-arm study was designed to assess the safety and efficacy of the CapeOx-pembrolizumab combination in advanced gastric cancer patients with HER2-negative. 38 patients were enrolled onto our CapeOx plus Pembrolizumab trial (NCT #04249739). All patients had MSS status with EBV-negative. Endoscopic biopsies were collected at baseline, after 1 cycle of chemotherapy alone and after 4 to 5 cycles of CapeOx + pembrolizumab to understand the impact of treatment to tumor TME. We performed coupling whole exome sequencing and whole transcriptome sequencing. Molecular features were extracted by exonic analysis. TME subtype was estimated by gene expression analysis. Results: Between 2020 and 2021, 38 patients were enrolled. There were 2 CR, 25 PR, 11 SD as best response.First, we found a number of somatic mutations (median 157.5, range 7-25,719) in pre-and on-treatment samples. Despite the creation and destruction of somatic mutation, we observed that ancestor mutations including TP53, MUC6 and APC previously reported in TCGA GC cohort, were preserved. At baseline (before chemotherapy), patients were classified to 5 immune-enriched (IE) subtye, 21 immune-depleted (D) subtype, ETC. Second, we observed a dynamic change following one cycle of CapeOx before the addition of pembrolizumab to chemotherapy. Nine (23.68%) out of thirty eight patients with immune-depleted or fibrotic pre-treatment TME became immune-favorable during treatment. Interestingly, seventeen (58.62%) out of twenty nine patients with immune-unfavorable pre-treatment TME became immune-favorable following CapeOx plus Pembrolizumab chemotherapy. Conclusions: This is the first study to demonstrate TME change during CapeOx plus pembrolizumab at molecular levels and will have clinically meaningful performance in patients with metastatic GC. Clinical trial information: NCT#04249739.

Exosome in ascites can be a potential therapeutic target for gastric cancer with malignant ascites

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Background: Recently, exosomes widely distributed in body fluids, including blood, urine, saliva, and ascites, serve as an essential biomarker in cancers. Exosomes are considered as a cargo of potential oncogenic protein such as MET during cancer progression. Methods: Exosomes from the malignant ascites (exoAscites) of four patients with stage IV gastric cancers (GCs) were isolated by different serial centrifugation steps (300 g, 2000 g, 10,000 g, and 110,000 g at 4). After ultracentrifugation, nanoparticle tracking analysis, western blotting, and immunocytochemistry were performed for characterization of the exoAscites. Results: In this study, we enrolled 4 patients with malignant ascites which needed to be drained for symptom control. In all 4 patients, we successfully isolated highly concentrated exosomes in 50 ml of ascites (range, 55108 – 260 108exosomes/ml). (pt#1, 140108 particles/ml; pt#2, 138 108, pt#3, 55.6 108; pt#4, 260 108 exosomes/ml). In twopatients with MET amplification (METamp) in tumor specimens, exoAscites retrieved from the ascites harbored cMET protein in exosomes. In addition, the in-vitro cancer microenvironment model showed that tropism of exoAscitesharboring cMET oncogenic protein had the potential to induce cancer progression (EpCAM immunofluorescent intensity value; a 2.4-fold increase compared to control). In this model, the cancer invasiveness and angiogenesis were significantly enhanced by treatment with exoAscites with over time. (2.4-(EpCAM immunofluorescent intensity) and 3.6-(CD31 immunofluorescent intensity) fold increase, respectively). Furthermore, the cancer invasiveness was substantially increased as the exosome concentration increased from 0, 101, 103, 105, 107 exosome particles/ml. Cancer invasiveness measured by EpCAM immunofluorescent intensity was significantly decreased upon exosiMET treatment in MET amplified GC cells when compared to the control. Conclusions: For the first time, we demonstrated that exosomes from malignant ascites carry MET protein in their exosomes. Exosomes may be early mediators of cancer spread in GC.

Determining Which Patients Require Preoperative Pelvic Radiotherapy Before Curative-Intent Surgery and/or Ablation for Metastatic Rectal Cancer

BACKGROUND

The aim of this study is to determine the optimal indications for preoperative pelvic radiotherapy (RT) in patients with metastatic rectal cancer who underwent curative-intent surgical resection and/or ablation.

METHODS

Between January 2000 and October 2019, 246 patients who met our inclusion criteria were enrolled. Preoperative RT was performed in 22 patients (8.9%). Lower margin below the peritoneal reflection (p < 0.001), mesorectal fascia (MRF) invasion (p = 0.02), and lateral pelvic lymph node (LPLN) involvement (p = 0.005) were more frequent in the preoperative RT group.

RESULTS

During the median follow-up period of 13.3 months (interquartile range [IQR]: 6.0-36.3 months), local recurrence (LR) was identified in 60 patients (24.4%). It was the first site of recurrence in 45 of them (18.3%). Among them, three patients were in the preoperative RT group. On multivariable analysis, lower margin below the peritoneal reflection, MRF invasion, LPLN involvement, carcinoembryonic antigen (CEA) level ≥ 10 ng/mL before treatment, and preoperative RT were significant prognostic factors for LR-free survival (LRFS). In the patient group without any risk factors, the 2-year LRFS rate was 94.9% without preoperative RT. In the patient group with one or more risk factors, the 2-year LRFS was 64.4% without and 95.2% with preoperative RT.

CONCLUSION

LR developed in about 25% of patients within 2 years. Preoperative RT should be considered, especially in patients with a risk factor for LR, including lower margin below the peritoneal reflection, MRF invasion, LPLN involvement, or CEA ≥ 10 ng/mL before treatment.

Early Tumor-Immune Microenvironmental Remodeling and Response to First-Line Fluoropyrimidine and Platinum Chemotherapy in Advanced Gastric Cancer

Chemotherapy is ubiquitous in first-line treatment of advanced gastric cancer, yet responses are heterogeneous, and little is known about mediators of chemotherapy response. To move forward, an understanding of the effects of standard chemotherapy on the tumor-immune microenvironment (TME) is needed. Coupling whole-exome sequencing, bulk RNA and single-cell transcriptomics from paired pretreatment and on-treatment samples in treatment-naïve patients with HER2-positive and HER2-negative gastric cancer, we define features associated with response to platinum-based chemotherapy. Response was associated with on-treatment TME remodeling including natural killer (NK) cell recruitment, decreased tumor-associated macrophages, M1-macrophage repolarization, and increased effector T-cell infiltration. Among chemotherapy nonresponders, we observed low/absent PD-L1 expression or modulation, on-treatment increases in Wnt signaling, B-cell infiltration, and LAG3-expressing T cells coupled to an exodus of dendritic cells. We did not observe significant genomic changes in early on-treatment sampling. We provide a map of on-treatment TME modulation with standard chemotherapy and nominate candidate future approaches.

SIGNIFICANCE

Using paired pretreatment and on-treatment samples during standard first-line chemotherapy, we identify chemotherapy-induced NK-cell infiltration, macrophage repolarization, and increased antigen presentation among responders. Increased LAG3 expression and decreased dendritic cell abundance were seen in nonresponders, emphasizing remodeling of the TME during chemotherapy response and resistance. This article is highlighted in the In This Issue feature, p. 873.

Safety and anti-tumor effects of vismodegib in patients with refractory advanced gastric cancer: A single-arm, phase-II trial

This phase-II study (ClinicalTrials.gov identifier: NCT03052478) aimed to evaluate the efficacy and safety of vismodegib, an inhibitor targeting the Hedgehog signaling pathway, in patients with refractory advanced gastric cancer. Patients with refractory advanced gastric cancer, whose disease had progressed after undergoing standard therapies, were enrolled in this phase-II trial of vismodegib. Vismodegib (150 mg) was administered orally once a day for a 21-day cycle. The primary endpoint was objective response rate, and the secondary endpoints were overall survival and safety profile. Tumor biopsies were obtained before vismodegib treatment. We conducted whole-exome and transcriptome sequencing to analyze biomarkers. Twenty-three patients were enrolled in this study. Among 19 patients who were eligible for response evaluation, only one showed stable disease, yielding a disease control rate of 5.3%. Median overall survival was 74 days (95% confidence interval, 74-151 days). Treatment-related adverse events of any grade were reported in seven patients (31.8%), and most were grade 1 or 2. Whole transcriptome data showed that the Hedgehog signaling pathway was not enriched in patient samples. This is the first clinical trial demonstrating the clinical activity and safety of vismodegib monotherapy in refractory advanced gastric cancer patients. Further well-designed clinical trials should be conducted to select advanced gastric cancer patients who are likely to benefit from vismodegib.

Exploration of predictors of benefit from nivolumab monotherapy for patients with pretreated advanced gastric and gastroesophageal junction cancer: post hoc subanalysis from the ATTRACTION-2 study

BACKGROUND

The phase 3 ATTRACTION-2 study demonstrated that nivolumab monotherapy was superior to placebo for patients with pretreated advanced gastric or gastroesophageal junction cancer, but early progression of tumors in some patients was of concern.

METHODS

This post hoc analysis statistically explored the baseline characteristics of the ATTRACTION-2 patients and extracted a single-factor and double-factor combinations associated with early disease progression or early death. In the extracted patient subgroups, the 3-year restricted mean survival times of progression-free survival and overall survival were compared between the nivolumab and placebo arms.

RESULTS

Two single factors (age and peritoneal metastasis) were extracted as independent predictors of early progression, but none of them, as a single factor, stratified patients into two subgroups with significant differences in restricted mean survival time. In contrast, two double-factor combinations (serum sodium level and white blood cell count; serum sodium level and neutrophil-lymphocyte ratio) stratifying patients into two subgroups with significant differences in the restricted mean survival time were extracted. Additional exploratory analysis of a triple-factor combination showed that patients aged < 60 years with peritoneal metastasis and low serum sodium levels (approximately 7% of all patients) might receive less benefit from nivolumab, and patients aged ≥ 60 years with no peritoneal metastasis and normal serum sodium levels might receive higher benefit.

CONCLUSIONS

A combination of age, peritoneal metastasis, and serum sodium level might predict benefit from nivolumab as salvage therapy in advanced gastric or gastroesophageal junction cancer patients, especially less benefit for patients having all three risk factors.

The Impact of Tumor Mutation Burden on the Effect of Frontline Trastuzumab Plus Chemotherapy in Human Epidermal Growth Factor Receptor 2-Positive Advanced Gastric Cancers

Background

Trastuzumab is a HER2-trargeted humanized monoclonal antibody that has been studied as a first-line treatment for patients with HER2-positive advanced gastric cancer (AGC). The effect of anti-HER2 therapy according to tumor mutational burden (TMB) in HER2-positive AGC remains unclear.

Methods

We performed next-generation sequencing (NGS), including TMB analysis, in 31 HER2-positive AGC patients with trastuzumab plus chemotherapy as first-line therapy for recurrent (n=8) or metastatic (n=23) tumors. The TruSight Oncology 500 Assay from Illumina (San Diego, CA, USA) was used to evaluate TMB.

Results

Among 31 patients, 30 had tumors with immunohistochemistry (IHC) 3+, and one was IHC 2+ and silver in situ hybridization (SISH) positive. The median age was 57.0 years old (range, 35-76), and the majority had tumors with low TMB (87.1%, n=27/31). Only four (12.9%) had tumors with high TMB. Of these four, three achieved complete response (CR) or partial response (PR) to treatment, and the remaining patient was not evaluable for tumor response. Objective response rate (ORR) to trastuzumab plus chemotherapy showed a favorable trend in patients with high TMB (75.0%, n=3/4) compared to patients with low TMB (59.3%, n=16/27) (P=0.546). The median progression-free survival (PFS) was not reached in the TMB-high group but was 8.0 months (95% CI, 7.6-8.5) in the TMB-low group (P=0.019)

Conclusion

The status of TMB could be a novel biomarker in predicting the efficacy of trastuzumab plus chemotherapy in HER2-positive AGCs.

A phase I study of IMC-001, a PD-L1 blocker, in patients with metastatic or locally advanced solid tumors

Introduction IMC-001 is a fully human IgG1 monoclonal antibody that binds to human PD-L1 (programmed death-ligand 1). This study evaluated the safety, pharmacokinetics, and pharmacodynamics of IMC-001 in patients with advanced solid tumors. Materials and Methods This open-labeled phase I study used a standard 3 + 3 dose-escalation design, with doses ranging from 2 to 20 mg/kg. IMC-001 was administered intravenously every 2 weeks until disease progression or unacceptable toxicity. The dose-limiting toxicity window was defined as 21 days from the first dose. Results Fifteen subjects were included in 5 dose-escalation cohorts. No dose-limiting toxicity was observed, and the maximum tolerated dose was not reached. The most common adverse events (AEs) were general weakness, decreased appetite, fever, and cough. No grade 4 or 5 treatment emergent AEs were reported during the study. One subject in the 2 mg/kg cohort showed grade 2 immune-induced thyroiditis and diabetes mellitus suspected to be related to IMC-001. Over the dose range of 2-20 mg/kg IMC-001, the AUC0-14d, AUC0-∞, and Cmax generally increased in a dose-proportional manner for each step of dose escalation. Of the 15 enrolled patients, 1 subject with rectal cancer showed a partial response, and the disease control rate was 33.3%. Conclusions IMC-001 demonstrated a favorable safety profile up to 20 mg/kg administered intravenously every 2 weeks and showed preliminary efficacy in patients with advanced solid tumors. Based on pharmacokinetic and pharmacodynamic data, 20 mg/kg was selected as the recommended phase II dose. Clinical trial identification NCT03644056 (date of registration: August 23, 2018).

Analysis of intrapatient heterogeneity of circulating tumor cells at the single-cell level in the cerebrospinal fluid of a patient with metastatic gastric cancer

Background

The aims of this study were to detect circulating tumor cells (CTCs) at the single-cell level in cerebrospinal fluid (CSF) and to identify intrapatient heterogeneity of CTCs in a patient with gastric cancer (GC) with leptomeningeal metastasis (LM) using Di-Electro-Phoretic Array technology.

Materials and Methods

The CSF samples were drawn from a patient who was diagnosed with GC with LM. The CSF samples were centrifuged and stained with antibody cocktail to recognize 4',6-diamidino-2-phenylindole, cytokeratin, and epithelial cell adhesion molecule (EpCAM). Gene sequencing was also conducted to evaluate the status of the gene alteration profile of CSFCTCs as compared with those of the CSF non-CTCs and the primary tumor tissue.

Results

Among total 38 cells from the samples, 25 cells represented CK+ (EpCAM+), which boiled down to 0.53 CTCs in 1 mL of CSF. Each CTC was heterogeneous in terms of morphology and degree of marker expression. Some CTCs have a spindle-like shape, whereas others have a round shape. Based on molecular profiling between the 25 CK+ (EpCAM+) CTCs and 13 CK-/EpCAM- cells (i.e., the non-CTCs), CSFCTCs harbored mutations such as MDM2, TP53, KRAS, STK11, and ALK, whereas mutation of these genes was not observed in the CSF non-CTCs. Four genes of nine mutational genes totally observed in the CSFCTCs were also noted in the primary tumor tissue.

Conclusions

We enriched CTCs through a single-cell sorting process in CSF samples of a GC patient with LM. We also demonstrated the intrapatient heterogeneity of the CTCs at the single-cell level.

The prevalence of homologous recombination deficiency (HRD) in various solid tumors and the role of HRD as a single biomarker to immune checkpoint inhibitors

Purpose

Homologous recombination deficiency (HRD) is related to tumorigenesis. Currently, the possibility of HRD as a prognostic biomarker to immune checkpoint inhibitors is unknown. We aimed to investigate whether HRD has potential as a biomarker for immunotherapy.

Methods

The status of homologous recombination deficiency (HRD) was assessed with the next-generation sequencing (NGS) TruSight^™ Oncology 500 assay in 501 patients with advanced solid tumor including gastrointestinal (GI), genitourinary (GU), or rare cancer. Results: among the 501 patients, HRD was observed as follows: 74.7% (347/501) patients; GU cancer (92.0%, 23 of 25), colorectal cancer (CRC) (86.1%, 130 of 151), hepatocellular carcinoma (HCC) (83.3%, 10 of 12), pancreatic cancer (PC) (76.2%, 32 of 42), biliary tract cancer (BTC) (75.0%, 36 of 48), sarcoma (65.0%, 39 of 60), melanoma (52.4%, 11 of 21), other GI cancers (50.0%, 11 of 22), and rare cancer (50.0%, 2 of 4). Sixty-five of the 501 patients had received immune checkpoint inhibitors (ICIs) during the course of the disease. Tumor types of 65 patients treated with ICIs are as follows: melanoma (95.2%, 20 of 21), HCC (33.3%, 4 of 12), rare cancer (25.0%, 1 of 4), GC (12.2%, 14 of 116), BTC (10.4%, 5 of 48), and sarcoma (5.0%, 3 of 60). The most frequently reported mutations were BRCA2 (n = 90), ARID1A (n = 77), ATM (n = 71), BARD1 (n = 67). Patients without HRD exhibited an objective response rate (ORR) of 33.3% (4 of 12), and patients with HRD exhibited an ORR of 34.0% (18 of 53). There was no significant difference in ORR between patients with and without HRD (P = 0.967). Progression-free survival (PFS) was 6.5 months (95% CI 0.000–16.175) in patients without HRD and 4.1 months (95% CI 2.062–6.138) in patients with HRD, revealing no statistical significance (P = 0.441).

Conclusion

Herein, we reported the status of HRD using a cancer-panel for various solid tumor patients in routine clinical practice and demonstrated that HRD as a single biomarker was not sufficient to predict efficacy of ICIs in solid tumor patients.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00432-021-03781-6.

When to apply immune checkpoint inhibitor in patients with refractory advanced gastric cancer

Background: Immune checkpoint inhibitors (ICIs) show clinical benefit in patients with refractory advanced gastric cancer (GC). The ICIs in routine clinical practice have been used in various treatment lines. Therefore, we investigated the timing for application of ICI in patients with refractory advanced GC.

Methods: We analyzed 187 patients with refractory advanced or recurrent GC who received ICIS as a 3rd- or 4th-line treatment between September 2015 and October 2020. Clinical outcomes of overall survival (OS), progression-free survival (PFS), objective response rate (ORR), and disease control rate (DCR) were evaluated.

Results: Among 187 patients, 105 received ICIs as a 3rd-line treatment and 82 as a 4th line. The ORR for ICIs was 10.5% (11/105) in 3rd line and 8.5% (7/82) in 4th line. The DCR for ICIs was 36.2% (38/105) in 3rd-line treatment and 31.7% (26/82) in 4th line. There was no significant difference for ORR (P = 0.819) or DCR (P = 0.870). The median PFS and OS to ICIs was 1.4 months (95% CI, 1.1 to 1.8 months) and 4.4 months (95% CI, 1.6 to 7.2 months) in 3rd line and 1.8 months (95% CI, 1.4 to 2.3 months) and 2.8 months (95% CI, 2.2 to 3.4 months) in 4th line. The median PFS and OS to ICIs was not different between 3rd line and 4th line (P = 0.495 and P=0.208, respectively). There were also no significant difference for PFS and OS between PD-L1-positive tumors (CPS≥1) and PD-L1-negative tumors (P = 0.910 and P=0.931, respectively).

Conclusions: ICIs showed similar clinical benefits in the 3rd-line and 4th-line settings. ICIs might be a reasonable approach for patients with refractory GC in the setting of 3rd-line or 4th-line treatment options.

Prognostic Impact of Sarcopenia and Radiotherapy in Patients With Advanced Gastric Cancer Treated With Anti-PD-1 Antibody

Background

We explored the combined effects of sarcopenia (SAR) and radiotherapy (RT) on outcomes in patients with advanced gastric cancer (AGC) treated with immune-checkpoint blockade (ICB).

Methods

Among 185 patients with AGC treated with ICB, we defined SAR as skeletal muscle index <49 cm2/m2 for men and <31 cm2/m2 for women; 93 patients met criteria. We defined high neutrophil-to-lymphocyte ratio (hNLR) as NLR≥3. Palliative RT was performed in 37 patients (20%) before ICB.

Results

We frequently observed hNLR in patients with SAR (53% vs. 35%, p = 0.02). The median overall survival (OS) for the entire cohort was 5 months. Stratification by risk factors of SAR or hNLR revealed a significant difference in median OS (0 [N = 60] vs. 1 [N = 76] vs. 2 [N = 49]: 7.6 vs. 6.4 vs. 2.2 months, p < 0.001). Patients with microsatellite instability-high (MSI-H, N = 19) or Epstein-Barr virus (EBV)-positive tumors (N = 13) showed favorable outcomes compared to those with microsatellite stable (MSS, N = 142) tumors (median OS, not reached vs. 16.8 vs. 3.8 months, respectively). The benefit of RT was evident in patients with both SAR and hNLR (median OS, 3.1 vs. 1.3 months, p = 0.02) and MSS/EBV-negative tumor (median OS, 6.5 vs. 3.5 months, p = 0.03), but outcomes after RT in MSI-H tumor were not significantly different. In multivariable analysis, SAR/hNLR, molecular subtypes, and a history of RT were associated with OS (all p < 0.05).

Conclusions

We demonstrated the negative predictive value of SAR/hNLR on outcomes after ICB for AGC, and the history of RT could overcome the negative impact of SAR/hNLR and the MSS/EBV-negative subtype.

Clinical scoring system for the prediction of survival of patients with advanced gastric cancer

OBJECTIVE

In this study, we established a risk scoring system using easily obtained clinical characteristics at the time of initiating palliative chemotherapy to predict accurate overall survival of patients with advanced gastric cancer after first-line treatment with fluoropyrimidine-platinum combination chemotherapy.

METHODS

A total of 1733 patients treated at the Samsung Medical Center, Korea were included in the study, and clinicopathological and laboratory data were retrospectively analysed. The dataset was split into a training set (n=1156, 67%) and a validation set (n=577, 33%). Top-ranked variables were identified using the random forest survival algorithm and integrated into a Cox regression model, thereby constructing the scoring system for predicting the overall survival of patients with advanced gastric cancer.

RESULTS

The following five variables were finally included in the scoring system: serum neutrophil-lymphocyte ratio, alkaline phosphatase level, albumin level, performance status and histologic differentiation. The scoring system determined four distinct risk groups in the validation dataset with median overall survival of 17.1 months (95% CI=14.9 to 20.5 months), 12.9 months (95% CI=11.4 to 14.6 months), 8.1 months (95% CI=5.3 to 12.3 months) and 3.9 months (95% CI=1.5 to 8.2 months), respectively. The area under the curve to estimate the discrimination performance of the scoring system was 66.1 considering 1 year overall survival.

CONCLUSIONS

We developed a simple and clinically useful predictive scoring model in a homogeneous population with advanced gastric cancer treated with fluoropyrimidine-containing and platinum-containing chemotherapy. However, additional independent validation will be required before the scoring model can be used commonly.

Prediction of epithelial-to-mesenchymal transition molecular subtype using CT in gastric cancer

OBJECTIVES

To develop a prediction model with computed tomography (CT) images and to build a nomogram incorporating known clinicopathologic variables for individualized estimation of epithelial-to-mesenchymal transition (EMT) subtype gastric cancer.

METHODS

Patients who underwent primary resection of gastric cancer (GC) and molecular subgroup analysis (n = 451) were reviewed. Multivariable analysis using a stepwise variable selection method was performed to build a predictive model for EMT subtype GC. A nomogram using the results of the multivariable analysis was constructed. An optimal cutoff value of total prognostic points of the nomogram for the prediction of EMT subtype was determined. The predictive model for the EMT subtype was internally validated by bootstrap resampling method.

RESULTS

There were 88 patients with EMT subtype and 363 patients with non-EMT subtype based on transcriptome analysis. The patient's age, Lauren classification, and mural stratification on CT were variables selected for the predictive model. The area under the curve (AUC) of the model was 0.865, and the validated AUC of the bootstrap sample was 0.860. The optimal cutoff value of total prognostic points for the prediction of EMT subtype was 94.622, with 90.9% sensitivity, 67.2% specificity, and 71.8% accuracy.

CONCLUSION

A predictive model using patient's age, Lauren classification, and mural stratification on CT for EMT molecular subtype GC was made. A nomogram was built which would serve as a useful screening tool for an individualized estimate of EMT subtype.

KEY POINTS

• A predictive model for epithelial-to-mesenchymal transition (EMT) subtype incorporating patient's age, Lauren classification, and mural stratification on CT was built. • The predictive model had high diagnostic accuracy (area under the curve (AUC) = 0.865) and was validated (bootstrap AUC = 0.860). • Adding CT findings to clinicopathologic variables increases the accuracy of the predictive model than using only.

Phase I Study of Ceralasertib (AZD6738), a Novel DNA Damage Repair Agent, in Combination with Weekly Paclitaxel in Refractory Cancer

PURPOSE

Ceralasertib is a potent and selective oral inhibitor of the serine/threonine protein kinase ataxia telangiectasia and Rad3-related (ATR) protein.

PATIENTS AND METHODS

Eligible patients with solid tumors, enriched for melanoma, received ceralasertib in combination with a fixed dose of paclitaxel (80 mg/m² on D1, D8, D15) in 28-day cycles. The dose of ceralasertib was escalated to reach an MTD in a rolling 6 design. The starting dose of ceralasertib was 40 mg QD. Fifty-seven patients (33 patients with melanoma who failed prior PD1/L1 treatment) were enrolled in 7 dose cohorts ranging from 40 mg QD to 240 mg BD plus weekly paclitaxel.

RESULTS

The RP2D was established as ceralasertib 240 mg BD days 1-14 plus paclitaxel 80 mg/m² on D1, D8, D15 every 28 days. The most common toxicities were neutropenia (n = 39, 68%), anemia (n = 25, 44%), and thrombocytopenia (n = 21, 37%). In the full analysis set of 57 patients, the overall response rate (ORR) was 22.6% (95% CI, 12.5-35.3). In 33 patients with melanoma, resistant to prior anti-PD1 therapy, the ORR was 33.3% (95% CI, 18.0-51.8). In the melanoma subset, the mPFS was 3.6 months (95% CI, 2.0-5.8), the median duration of response was 9.9 months (95% CI, 3.7-23.2), and the mOS was 7.4 months (95% CI, 5.7-11.9).

CONCLUSIONS

Ceralasertib in combination with paclitaxel was well tolerated in patients with advanced malignancies and showed evidence of antitumor activity. Durable responses were observed in patients with advanced cutaneous, acral, and mucosal melanoma resistant to anti-PD1/L1 treatment.See related commentary by Ashworth, p. 4667.

Comparison of postoperative outcomes between early and delayed surgery for pediatric nasal fractures

Background

Pediatric nasal fractures, unlike adult nasal fractures, are treated surgically as early as 7 days after the initial trauma. However, in some cases, a week or more elapses before surgery, and few studies have investigated the consequences of delayed surgery for pediatric nasal fractures. The purpose of this study was to evaluate the postoperative outcomes of pediatric nasal fractures according to the time interval between the initial trauma and surgery.

Methods

The records of pediatric patients under 12 years old who underwent closed reduction of nasal bone fracture from March 2012 to February 2020 were reviewed. The interval between trauma and surgery was divided into within 7 days (early reduction) and more than 7 days (delayed reduction). Postoperative results were classified into five grades (excellent, good, moderate, poor, and very poor) based on the degree of reduction shown on computed tomography.

Results

Ninety-eight patients were analyzed, of whom 51 underwent early reduction and 47 underwent delayed reduction. Forty-two (82.4%) of the 51 patients in the early reduction group showed excellent results, and nine (17.6%) showed good results. Thirty-nine (83.0%) of the 47 patients in the delayed reduction group showed excellent results and eight (17.0%) showed good results. No statistically significant difference in outcomes was found between the two groups (chi-square test p=0.937). However, patients without septal injury were significantly more likely to have excellent postoperative outcomes (chi-square test p<0.01).

Conclusion

No statistically significant difference was found in the outcomes of pediatric nasal fractures between the early and delayed reduction groups. Successful surgical results were found even in patients who received delayed reduction (more than 7 days after trauma).

Determinants of Response and Intrinsic Resistance to PD-1 Blockade in Microsatellite Instability-High Gastric Cancer

Sequence alterations in microsatellites and an elevated mutational burden are observed in 20% of gastric cancers and associated with clinical response to anti-PD-1 antibodies. However, 50% of microsatellite instability-high (MSI-H) cancers are intrinsically resistant to PD-1 therapies. We conducted a phase II trial of pembrolizumab in patients with advanced MSI-H gastric cancer and included serial and multi-region tissue samples in addition to serial peripheral blood analyses. The number of whole-exome sequencing (WES)-derived nonsynonymous mutations correlated with antitumor activity and prolonged progression-free survival (PFS). Coupling WES to single-cell RNA sequencing, we identified dynamic tumor evolution with greater on-treatment collapse of mutational architecture in responders. Diverse T-cell receptor repertoire was associated with longer PFS to pembrolizumab. In addition, an increase in PD-1⁺ CD8⁺ T cells correlated with durable clinical benefit. Our findings highlight the genomic, immunologic, and clinical outcome heterogeneity within MSI-H gastric cancer and may inform development of strategies to enhance responsiveness. SIGNIFICANCE: This study highlights response heterogeneity within MSI-H gastric cancer treated with pembrolizumab monotherapy and underscores the potential for extended baseline and early on-treatment biomarker analyses to identify responders. The observed markers of intrinsic resistance have implications for patient stratification to inform novel combinations among patients with intrinsically resistant features.See related commentary by Fontana and Smyth, p. 2126.This article is highlighted in the In This Issue feature, p. 2113.

Programmed Death Ligand 1 Expression as a Prognostic Marker in Patients with Advanced Biliary Tract Cancer

BACKGROUND

Biliary tract cancer (BTC) is associated with poor prognosis because of its aggressive and heterogeneous nature. Programmed death ligand 1 (PD-L1) has been considered a novel biomarker for prognosis and response of immune checkpoint inhibitors in various tumors. However, there are limited data reporting on the role of PD-L1 in advanced BTC patients.

PATIENTS AND METHODS

We analyzed 186 patients with advanced BTC who received palliative gemcitabine and platinum between May 2010 and December 2019. All patients were evaluated for PD-L1 expression by combined positive score positivity.

RESULTS

Of the 186 patients, the primary tumor location was intrahepatic cholangiocarcinoma (IHCC) in 72 (38.7%), extrahepatic cholangiocarcinoma (EHCC) in 90 (48.4%), and gallbladder (GB) cancer in 24 (12.9%). Among all the patients, 53 (28.5%) had PD-L1 positivity. The median overall survival (OS) of patients with PD-L1 positivity or negativity was 12.1 and 15.4 months, respectively. The median progression-free survival (PFS) in patients with PD-L1 positivity or negativity was 5.7 and 7.1 months, respectively. OS and PFS were not statistically different between groups. In subgroup analysis, EHCC patients with PD-L1 negativity had more favorable OS (17.2 vs. 11.6 months, p = 0.002) and PFS (7.8 vs. 5.4 months, p = 0.005) than those who were PD-L1-positive. However, this finding was not reproduced in patients with IHCC or GB cancer.

CONCLUSION

This study demonstrated that PD-L1 expression might be a novel prognostic biomarker in patients with EHCC but not in patients with IHCC or GB cancer.

Pemetrexed/Erlotinib as a Salvage Treatment in Patients with High EGFR-Expressing Metastatic Colorectal Cancer Following Failure of Standard Chemotherapy: A Phase II Single-Arm Prospective Study

BACKGROUND

Despite new agents to treat metastatic colorectal cancer (CRC), patients eventually progress and additional therapies are needed.

OBJECTIVE

We intended to evaluate the combination of pemetrexed/erlotinib in patients with high epidermal growth factor receptor (EGFR)-expressing (2+ or 3 on immunohistochemistry) metastatic CRC who experienced disease progression after standard chemotherapy.

PATIENTS AND METHODS

We investigated pemetrexed and erlotinib (pemetrexed 500 mg/m² on Day 1 and erlotinib 100 mg/m² on Days 1-21) as a salvage treatment, given every 3 weeks, until disease progression or intolerable toxicity. The primary outcome was overall response rate (RR).

RESULTS

From May 2017 to April 2018, 29 metastatic CRC patients with high EGFR expression who had previously received standard therapies were enrolled into this trial. The regimen was well tolerated. Skin rash, vomiting, fatigue, and anorexia were common toxic effects but were mostly manageable and controllable side effects of grades 1 or 2 only. In an intent-to-treat analysis, three partial responses (PRs) were observed in enrolled patients, revealing an overall RR of 10.3%. This value supported the statistical hypothesis of this study. Fifteen patients had stable disease and the disease control rate (DCR) was 62.1%. All three patients who achieved a PR had a tumor EGFR expression of 3+. Among the eight patients with EGFR 3+ expression, the RR and DCR were 37.5% and 75.0%, respectively.

CONCLUSION

This phase II trial using pemetrexed/erlotinib in metastatic CRC with high EGFR expression met the primary endpoint of tumor response.

TRIAL REGISTRATION

This study was registered at ClinicalTrials.gov (number NCT03086538).

Clinical sequencing to assess tumor mutational burden as a useful biomarker to immunotherapy in various solid tumors

Background:

Immune checkpoint inhibitors (ICIs) have become established as a new therapeutic paradigm in various solid cancers. Predictive biomarkers to ICIs have not yet been fully established. Tumor mutational burden (TMB) has been considered as a useful marker to indicate patients who benefit from ICIs.

Methods:

We performed next-generation sequencing, including TMB analysis, as a routine clinical practice in 501 patients with advanced gastrointestinal (GI), genitourinary (GU), or rare cancers. The TruSight^™ Oncology 500 assay from Illumina was used as a cancer panel.

Results:

In total, 11.6% (58/501) were identified with tumors with high TMB and MSI-high status was confirmed in seven out of 501 cases (1.4%). High TMB was observed in 11.6% of patients with various solid tumors, including: GU cancers (36.0%, 9/25), colorectal cancer (15.2%, 23/151), biliary tract cancer (14.6%, 7/48), melanoma (14.3%, 3/21), gastric cancer (11.2%, 13/116), hepatocellular carcinoma (8.3%, 1/12), other GI tract cancers (4.5%, 1/22), and sarcoma (1.7%, 1/60). The objective response rate (ORR) to ICIs was 75% (nine out of 12) in solid tumor patients with high TMB and 25% (30 out of 40) in those with non-high TMB. Patients with high TMB had better ORR to ICIs than those with non-high TMB (p = 0.004). Univariate analysis revealed that the status of PD-L1 expression and of TMB (high versus non-high) had significant association in response to ICIs. However, in multivariate analysis, the status of TMB (high versus non-high) was only significantly related to the response to ICIs (p = 0.036).

Conclusion:

In the present study, we analyzed the TMB using a cancer panel for various solid tumor patients in routine clinical practice and also demonstrated the usefulness of TMB to predict the efficacy for ICIs.

Comprehensive molecular characterization of gastric cancer patients from phase II second-line ramucirumab plus paclitaxel therapy trial

BACKGROUND

Gastric cancer (GC) is a heterogenous disease consisted of several subtypes with distinct molecular traits. The clinical implication of molecular classification has been limited especially in association with treatment efficacy of ramucirumab or various targeted agents.

METHODS

We conducted a prospective non-randomized phase II single-arm trial of ramucirumab plus paclitaxel as second-line chemotherapy in 62 patients with metastatic GC who failed to respond to first-line fluoropyrimidine plus platinum treatment. For integrative molecular characterization, all patients underwent pre-ramucirumab treatment tissue biopsy for whole-exome/whole-transcriptome sequencing to categorize patients based on molecular subtypes. We also systematically performed integrative analysis, combining genomic, transcriptomic, and clinical features, to identify potential molecular predictors of sensitivity and resistance to ramucirumab treatment.

RESULTS

Sixty-two patients were enrolled in this study between May 2016 and October 2017. Survival follow-up in all patients was completed as of the date of cut-off on January 2, 2019. No patient attained complete response (CR), while 22 patients achieved confirmed partial response (PR), resulting in a response rate (RR) of 35.5% (95% CI, 23.6-47.4). According to TCGA molecular classification, there were 30 GS, 18 CIN, 3 EBV, and 0 MSI tumors. The RR was 33% in GS (10/30), 33% in CIN (6/18), and 100% in EBV-positive GC patients with significant statistical difference for EBV(+) against EBV(-) tumors (P = 0.016; chi-squared test). Moreover, responsive patients were marked by activation of angiogenesis, VEGF, and TCR-associated pathways, while non-responder patients demonstrated enrichments of sonic hedgehog signaling pathway and metabolism activity. Integrative multi-layer data analysis further identified molecular determinants, including EBV status, and somatic mutation in GNAQ to ramucirumab activity.

CONCLUSIONS

Prospective molecular characterization identified a subset of GC patients with distinct clinical response to ramucirumab therapy, and our results demonstrate the feasibility of personalized therapeutic opportunities in gastric cancer.

TRIAL REGISTRATION

The study was registered on ClinicalTrial.gov ( NCT02628951 ) on June 12, 2015.

Prognostic Factors of Survival with Aflibercept and FOLFIRI (fluorouracil, leucovorin, irinotecan) as Second-line Therapy for Patients with Metastatic Colorectal Cancer

Background: Aflibercept and fluorouracil, leucovorin, irinotecan (FOLFIRI) is commonly used as a second-line treatment for metastatic colorectal cancer (CRC). However, the biomarkers to guide the choice of this regimen from among treatment options remain unclear.

Patients and Methods: We performed exploratory analyses to validate potential prognostic factors for patients receiving aflibercept plus FOLFIRI as a second-line systemic treatment for metastatic CRC between January 2015 and July 2019. Patient characteristics, histopathologic data, laboratory and radiologic data, and treatment outcomes were collected and reviewed.

Results: Included were 52 patients: 50 (96.2%) received bevacizumab plus fluorouracil, leucovorin, oxaliplatin (FOLFOX) as prior first-line treatment. Among the 52 patients receiving aflibercept and FOLFIRI, four complete responses and 21 partial responses were observed in analyzed patients for an overall response rate of 48.1%. Median progression-free survival (PFS) was 7.0 months and overall survival (OS) was 16.8 months. Response to first-line treatment (median PFS, 8.0 versus 4.2 months), left-side location of primary tumor (7.9 versus 4.9 months), low baseline CEA level (8.0 versus 5.9 months), and no RAS/RAF mutation (9.9 versus 6.4 months) were remained significant prognostic factors for PFS in the multivariate backward stepwise Cox regression model, and the latter three factors were also significantly related to OS.

Conclusions: Significant prognostic factors for PFS with aflibercept plus FOLFIRI as second-line therapy were extracted and validated in the multivariate OS model. These findings could provide useful information for selecting patients for aflibercept plus FOLFIRI as second-line therapy.

Nivolumab in previously treated advanced gastric cancer (ATTRACTION-2): 3-year update and outcome of treatment beyond progression with nivolumab

BACKGROUND

ATTRACTION-2 demonstrated that nivolumab improved overall survival (OS) vs placebo in patients with advanced gastric cancer treated with ≥ 2 chemotherapy regimens. However, its long-term efficacy and outcome of treatment beyond progression (TBP) with nivolumab have not been clarified.

METHODS

The 3-year follow-up data were collected. A subset analysis was performed to explore the efficacy of TBP by assessing postprogression survival (PPS) after the first event of disease progression.

RESULTS

Overall, 493 patients were randomized (2:1) to receive nivolumab (n = 330) or placebo (n = 163). With a median follow-up of 38.5 (range 36.1-47.5) months, OS of the nivolumab group was significantly longer compared to the placebo group (median 5.3 vs 4.1 months; 3-year survival rate, 5.6% vs 1.9%; hazard ratio [HR], 0.62 [95% confidence interval (CI) 0.50-0.75], P < 0.0001). The median OS of responders (n = 32) who achieved complete response or partial response was 26.7 months and the 3-year survival rate was 35.5% in the nivolumab group. Overall, 109 patients in the nivolumab group and 37 patients in the placebo group received TBP. PPS tended to be longer in the nivolumab group vs placebo group (median 5.8 vs 4.5 months; HR [95% CI], 0.69 [0.47-1.01], P = 0.057). In contrast, PPS was similar between both treatment groups in non-TBP patients (median 2.3 vs 2.2 months; HR 0.90, P = 0.42).

CONCLUSIONS

Long-term efficacy of nivolumab was confirmed at the 3-year follow-up, and a survival benefit of TBP with nivolumab was suggested. Biomarkers for selecting patients suitable for TBP with nivolumab should be identified in the future.

Impact of Radiotherapy on Kidney Function among Patients Who Received Adjuvant Treatment for Gastric Cancer: Logistic and Linear Regression Analyses

Simple Summary

Purpose of the present study was to investigate the incidence of renal function impairment after adjuvant treatment for gastric cancer and the impact of radiotherapy on estimated glomerular filtration rate (eGFR) five years after gastric surgery. Of the 663 patients who were followed up for ≥5 years without disease recurrence and whose baseline kidney function was normal, only 2.0% of patients developed renal function impairment after adjuvant treatment for gastric cancer. While radiotherapy was negatively associated with the five-year eGFR in linear regression analysis, its impact was minimal if the kidneys were properly shielded. This study could serve as a partial basis for further research on radiation-related renal function impairment in patients who received radiotherapy for abdominal malignancy.

Abstract

We investigated the incidence of renal function impairment after adjuvant treatment for gastric cancer and analyzed the impact of radiotherapy on estimated glomerular filtration rate (eGFR) five years after gastric surgery. We reviewed the medical records of 1490 patients with stomach cancer who underwent curative surgery and adjuvant treatment for gastric cancer. Finally, we included 663 patients who were followed up for ≥5 years without disease recurrence and whose baseline eGFR was ≥60 mL/min/1.73 m². Logistic and linear regression analyses were performed to determine independent factors associated with the five-year eGFR. A total of 13 (2.0%) patients developed renal function impairment (five-year eGFR <60 mL/min/1.73 m²). In logistic regression analysis, the baseline eGFR was identified as a prognostic factor for renal function impairment (odds ratio (OR), 0.878; 95% confidence interval (CI), 0.831–0.927; p < 0.001), but radiotherapy was not (OR, 1.130; 95% CI, 0.366–3.491; p = 0.832). In linear regression analysis, age (B = −0.350, p < 0.001), baseline eGFR (B = 0.576, p < 0.001), cisplatin (B = −2.056, p = 0.010), and radiotherapy (B = −2.628, p < 0.001) were predictive variables for the five-year eGFR. Among patients who received adjuvant radiotherapy, age (B = −0.277, p < 0.001), hypertension (B = −4.986, p = 0.004), baseline eGFR (B = 0.665, p < 0.001), and volume of the kidneys receiving ≥20 Gy (B = −0.209, p = 0.012) were predictive variables for the five-year eGFR. Development of renal function impairment after adjuvant treatment for gastric cancer was rare among patients with normal baseline kidney function. While radiotherapy was negatively associated with the five-year eGFR, its impact would have been minimal if the kidneys were properly shielded. Further studies are needed to confirm the impact of radiotherapy in patients with poor kidney function.

A randomized phase III trial comparing adjuvant single-agent S1, S-1 with oxaliplatin, and postoperative chemoradiation with S-1 and oxaliplatin in patients with node-positive gastric cancer after D2 resection: the ARTIST 2 trial☆

BACKGROUND

Adjuvant chemotherapy and chemoradiotherapy are some of the standards of care for gastric cancer (GC). The Adjuvant chemoRadioTherapy In Stomach Tumors (ARTIST) 2 trial compares two adjuvant chemotherapy regimens and chemoradiotherapy in patients with D2-resected, stage II or III, node-positive GC.

PATIENTS AND METHODS

The ARTIST 2 compared, in a 1:1:1 ratio, three adjuvant regimens: oral S-1 (40-60 mg twice daily 4 weeks on/2 weeks off) for 1 year, S-1 (2 weeks on/1 week off) plus oxaliplatin 130 mg/m² every 3 weeks (SOX) for 6 months, and SOX plus chemoradiotherapy 45 Gy (SOXRT). Randomization was stratified according to surgery type (total or subtotal gastrectomy), pathologic stage (II or III), and Lauren histologic classification (diffuse or intestinal/mixed). The primary endpoint was disease-free survival (DFS) at 3 years; a reduction of 33% in the hazard ratio (HR) for DFS with SOX or SOXRT, when compared with S-1, was considered clinically meaningful. The trial is registered at clinicaltrials.gov (NCT0176146).

RESULTS

A total of 546 patients were recruited between February 2013 and January 2018 with 182, 181, and 183 patients in the S-1, SOX, and SOXRT arms, respectively. Median follow-up period was 47 months, with 178 DFS events observed. Estimated 3-year DFS rates were 64.8%, 74.3%, and 72.8% in the S-1, SOX, and SOXRT arms, respectively. HR for DFS in the control arm (S-1) was shorter than that in the SOX and SOXRT arms: S-1 versus SOX, 0.692 (P = 0.042) and S-1 versus SOXRT, 0.724 (P = 0.074). No difference in DFS was found between SOX and SOXRT (HR 0.971; P = 0.879). Adverse events were as anticipated in each arm, and were generally well-tolerated and manageable.

CONCLUSIONS

In patients with curatively D2-resected, stage II/III, node-positive GC, adjuvant SOX or SOXRT was effective in prolonging DFS, when compared with S-1 monotherapy. The addition of radiotherapy to SOX did not significantly reduce the rate of recurrence after D2 gastrectomy.

Clinical and molecular distinctions in patients with refractory colon cancer who benefit from regorafenib treatment

Regorafenib (Stivarga, BAY 73-4506; Bayer Pharma AG, Berlin, Germany) is a novel oral multikinase inhibitor that blocks the activity of several protein kinases. However, few guidelines exist for novel biomarkers to select patients who will likely benefit from regorafenib treatment. Metastatic colorectal cancer (mCRC) patients treated with regorafenib were evaluated in this study. Tumor tissues of these patients were subjected to next-generation sequencing-based cancer panel tests. The relationship between molecular profiling and efficacy of regorafenib was analyzed. Among the 76 mCRC patients, the median age was 58 years (range 22–79 years), and 73.7% received regorafenib as a third-line therapy. The primary tumor locations were the right side (n = 15, 19.8%) and the left side (n = 61, 80.2%). Most patients (97.4%) had received prior anti-angiogenetic agents, and a prior anti-Epidermal Growth Factor Receptor (EGFR) agent had been administered to 32.9%. Of these 76 patients, 65 were evaluated to determine the efficacy of treatment. We observed zero complete responses, seven confirmed partial responses (PR 9.2%), 26 stable disease states (34.2%), and 32 disease progressions (42.1%). The overall confirmed response rate and the disease control rate were 9.2% and 43.4%, respectively. Genomic analysis revealed that APC mutations were significant in patients who demonstrated a tumor response to regorafenib (p < 0.05). Interestingly, FGFR1 amplification was detected in only three of 76 patients (3.9%), and these three patients achieved a PR to regorafenib. The median progression-free survival time was 2.8 months (95% Confidence Interval [CI] 1.6–4.0). Patients with BRAF mutation and/or SMAD4 mutation had significantly worse progression-free survival (PFS) than those without such a mutation. On pathway analysis, Tumor Growth Factor (TGF)-beta pathways were significantly associated with worse PFS. We found that efficacy of regorafenib might be correlated with specific genetic aberrations, such as APC mutation and FGFR1 amplification. In addition, SMAD4 mutation and TGF-beta pathway were associated with worse PFS after regorafenib. We found that efficacy of regorafenib might be correlated with specific genetic aberrations, such as APC mutation and FGFR1 amplification. In addition, SMAD4 mutation and the TGF-beta pathway were associated with worse PFS after regorafenib.

Phase I clinical trial of KML001 monotherapy in patients with advanced solid tumors

BACKGROUND

We evaluated the tolerability, pharmacokinetics (PK) and preliminary efficacy of KML001, an oral trivalent arsenical, as a monotherapy in patients with advanced solid tumors.

RESEARCH DESIGN AND METHODS

With a standard 3 + 3 design for dose-escalation stage, the planned dose levels of KML001 were 5, 7.5, 10, 12.5, and 15 mg/day for 28 days. Once the maximum tolerated dose was determined, 22 subjects were additionally enrolled for dose-expansion stage. PK analysis was performed in the 5, 10, and 15 mg/day cohort at the dose-escalation stage and also at the dose-expansion stage. Moreover, response was assessed using the standard RECIST 1.1.

RESULTS

A total of 45 Korean subjects were enrolled. No DLT was reported at the dose-escalation stage. Three DLTs, two cases of prolonged QTc interval and one of neutropenia, were reported in the 12.5 mg/day cohort at the dose-expansion stage. Higher total daily doses up to 12.5 mg/day of KML001 resulted in higher trough plasma concentrations. Among the 18 subjects who completed 2 cycles of therapy, 15 had progressive disease and 3 had stable disease.

CONCLUSIONS

Doses equal to or greater than 10 mg/day KML001 alone were tolerable and produced plasma concentrations higher than biologically relevant targets.

Effect of baseline sarcopenia on adjuvant treatment for D2 dissected gastric cancer: Analysis of the ARTIST phase III trial

BACKGROUND AND PURPOSE

This study evaluated the clinical significance of preoperative sarcopenia according to adjuvant concurrent chemo-radiotherapy (XP-RT) or chemotherapy alone (XP) in the D2 dissected gastric cancer patient cohort of the ARTIST trial.

MATERIALS AND METHODS

Skeletal muscles at the L3 vertebra level from preoperative computed tomography images among the ARTIST trial participants were measured using validated in-house software. Skeletal muscle index (SMI) was defined as the measured skeletal muscle area divided by the square of the height, and sarcopenia was defined according to the Korean-specific cutoff, i.e. L3 SMI ≤ 49 cm²/m² for men and ≤31 cm²/m² for women.

RESULTS

Among the 440 patients in whom we were able to evaluate L3 SMI, 75 (17.0%) met the definition for preoperative sarcopenia. No differences in treatment-related toxicities or treatment compliance were observed according to the presence of preoperative sarcopenia in either treatment arm. In the subgroup of patients without preoperative sarcopenia, recurrence was significantly lower in the XP-RT arm than that in the XP arm (p = 0.02). Recurrence-free survival (RFS) was also significantly higher in the XP-RT arm (p = 0.02, hazard ratio 0.633, 95% confidence interval 0.433-0.926) in this subgroup. In the multivariate analysis, and after adjusting for significant prognostic factors, the superior outcome of XP-RT arm regarding RFS was maintained in the subgroup of the patients without preoperative sarcopenia.

CONCLUSIONS

Superior clinical outcomes of adjuvant XP-RT over XP were only observed in patients without preoperative sarcopenia.

Bone remodeling after conservative treatment of nasal bone fracture in pediatric patients

BACKGROUND

The standard treatment of nasal bone fractures in pediatric patients is closed reduction. Conservative treatment is sometimes performed, but poses a risk of nasal deformity. The aim of this study was to evaluate the outcomes of bone remodeling in pediatric nasal fractures.

METHODS

Information was extracted from the medical records of patients under 12 years of age who received conservative treatment for a nasal bone fracture and underwent follow-up computed tomography (CT) examinations. The initial fracture and its outcomes over time were graded as excellent, good, or fair according to the malalignment, displacement, or irregularity of the fractured segments. The outcomes of remodeling were evaluated through changes in the grade of the fracture between initial and subsequent CT scans.

RESULTS

The review identified 16 patients between March 2015 and December 2019. Their mean age was 6.2 years, and the average follow-up period was 4.9 months. Three of the five patients with a plane I frontal impact showed improved outcomes of remodeling from good to excellent, and the remaining two patients, improved from fair to good. Eight of the 11 patients with plane I lateral impacts showed improved outcomes, from good to excellent, while one patient, improved from fair to good, one patient, improved from fair to excellent, and one patient showed no interval changes.

CONCLUSION

In 15 of these 16 patients with non-severe fractures, the bony contour improved through remodeling, without surgical intervention. Therefore, we suggest that conservative treatment is a feasible option for mild pediatric nasal fractures.

First-in-human phase I trial of anti-hepatocyte growth factor antibody (YYB101) in refractory solid tumor patients

Background

YYB101, a humanized monoclonal antibody against hepatocyte growth factor (HGF), has shown safety and efficacy in vitro and in vivo. This is a first-in-human trial of this antibody.

Materials and Methods

YYB101 was administered intravenously to refractory cancer patients once every 4 weeks for 1 month, and then once every 2 weeks until disease progression or intolerable toxicity, at doses of 0.3, 1, 3, 5, 10, 20, 30 mg/kg, according to a 3+3 dose escalation design. Maximum tolerated dose, safety, pharmacokinetics, and pharmacodynamics were studied. HGF, MET, PD-L1, and ERK expression was evaluated for 9 of 17 patients of the expansion cohort (20 mg/kg).

Results

In 39 patients enrolled, no dose-limiting toxicity was observed at 0.3 mg/kg, and the most commonly detected toxicity was generalized edema (n = 7, 18.9%) followed by pruritis and nausea (n = 5, 13.5%, each), fatigue, anemia, and decreased appetite (n = 4, 10.8%, each). No patient discontinued treatment because of adverse events. YYB101 showed dose-proportional pharmacokinetics up to 30 mg/kg. Partial response in 1 (2.5%) and stable disease in 17 (43.5%) were observed. HGF, MET, PD-L1, and ERK proteins were not significant predictors for treatment response. However, serum HGF level was significantly lowered in responders upon drug administration. RNA sequencing revealed a mesenchymal signature in two long-term responders.

Conclusion

YYB101 showed favorable safety and efficacy in patients with refractory solid tumors. Based on this phase I trial, a phase II study on the YYB101 + irinotecan combination in refractory metastatic colorectal cancer patients is planned.

Conclusion

ClinicalTrials.gov Identifier: NCT02499224.

PD-L1 expression as a prognostic marker in patients with advanced biliary tract cancer

e16679

Background: Biliary tract cancer (BTC) is associated with poor prognosis because of its aggressive and heterogeneous nature. Programmed death ligand 1 (PD-L1) has been considered as a novel biomarker for prognosis and response of immune checkpoint inhibitors in various tumors. However, there are limited data reporting on the role of PD-L1 in advanced BTC patients. Methods: We analyzed 186 patients with advanced BTC who received palliative gemcitabine and platinum between May 2010 and December 2019. All patients were evaluated for PD-L1 expression by combined positive score (CPS) positivity. Results: In all 186 patients, the median age was 62 years (range 38-82), and the primary tumor location was intrahepatic cholangiocarcinoma (IH-CCC) in 72 patients (38.7%), extrahepatic (EH)-CCC in 90 (48.4%), and gallbladder (GB) cancer in 24 (12.9%). There were 158 (84.9%) patients with recurrent disease and 28 (15.1%) with metastatic disease. Among the 186 patients, 53 (28.5%) had PD-L1 CPS positivity, and 133 were CPS negative. The median overall survival (OS) of patients with PD-L1 CPS positivity or negativity was 12.1 and 15.4 months, respectively. The median progression-free survival (PFS) in patients with PD-L1 positivity or negativity was 5.7 and 7.1 months, respectively. The OS and PFS were not statistically different between groups. In sub-group analysis, EH-CCC patients with PD-L1 negativity had more favorable OS (17.2 vs. 11.6 months, p= 0.002) and PFS (7.8 vs. 5.4 months, p= 0.005) than those that were PD-L1 negative. However, this finding was not reproduced in patients with IH-CCC or GB cancer. Univariate analysis of the association between PD-L1 expression and OS in patients with advanced BTC indicated that PD-L1 CPS positivity has a prognostic role in sub-populations older than 60 years (HR 1.743, CI 1.001-3.034, p = 0.050), those with EH-CCC (HR 2.449, CI 1.355-4.426, p = 0.003), and those with liver metastasis (HR 2.511, CI 1.362-4.626, p = 0.003). Conclusions: This study demonstrated that PD-L1 expression might be a novel prognostic biomarker in patients with EH-CCC but not for patients with IH-CCC or GB cancer.

Claudin 18.2 expression in various tumor types and its role as a potential target in advanced gastric cancer

Background

Alterations in claudin expression can impair tight junction function, influence signaling pathways, and act as a tumor-promoting event in some epithelial cancers. Recently, zolbetuximab, a highly potent and tumor cell-selective therapeutic antibody against claudin 18.2, has been developed and investigated in clinical trials.

Methods

We conducted a prospective study using claudin 18.2 immunohistochemistry in 430 consecutive patients with advanced gastrointestinal, genitourinary, or rare cancers between June 2012 and March 2016.

Results

Claudin 18.2 expression was evaluated in 96.3% of the patients (414/430) using immunohistochemistry. In total, 4.1% (17/414) of the patients were claudin 18.2-positive, including patients with pancreatic (16.7%, 1/6), gastric (14.1%, 12/85), biliary tract (6.3%, 1/16), genitourinary/miscellaneous (2.2%, 1/46), and colorectal (0.9%, 2/203) cancers. Twelve of 17 patients positive for claudin 18.2 had gastric cancers (GCs); this subgroup showed no statistical differences by gender, age, disease extent, primary tumor site, pathologic differentiation, human epidermal growth factor receptor 2, or Epstein-Barr virus status with or without claudin 18.2 expression. However, claudin 18.2 was more frequently positive in intestinal-type compared with diffuse-type as assessed by Lauren classification (P=0.026). There was no significant difference in overall survival (OS) between patients with and without claudin 18.2 expression (P=0.101).

Conclusions

Our results add to the emerging literature about claudin 18.2 expression in various cancer types and support the need for extended clinical exploration of zolbetuximab.

Impact of Prior Ramucirumab Use on Treatment Outcomes of Checkpoint Inhibitors in Advanced Gastric Cancer Patients

BACKGROUND

A taxane plus ramucirumab as second-line therapy followed by a checkpoint inhibitor (CPI) in third line has become a standard treatment strategy for advanced gastric cancer.

OBJECTIVE

Herein, we investigated the impact of prior ramucirumab use on the efficacy of third-line immunotherapy and performed an exploratory analysis to identify potential biomarkers for the success of immunotherapy.

PATIENTS AND METHODS

We retrospectively analyzed patients receiving CPI as a third-line treatment for advanced gastric cancer between January 2015 and March 2019. Clinicopathologic data, including patient characteristics, histopathologic reports, and treatment types and outcomes, were reviewed.

RESULTS

Of the 74 patients included in this study, 45 (61%) received nivolumab and 29 (39%) received pembrolizumab as a third-line CPI. For second-line therapy, 41 patients (55%) were treated with ramucirumab plus a taxane, and 33 (45%) received a chemotherapy regimen without ramucirumab. The disease control rates of CPIs were not statistically different according to prior use of ramucirumab. The overall survival (OS) with CPI was higher in patients receiving second-line therapy without ramucirumab compared with those receiving ramucirumab and taxane (5.6 vs 4.8 months, HR 0.56, 95% confidence interval [CI] 0.33-0.96; p = 0.03); however, this was not significant in a multivariate analysis. Patients achieving a response to second-line ramucirumab and a taxane showed greater benefit from subsequent CPI treatment compared with those not achieving a response (median OS 9.9 vs 2.3 months, HR 0.20, 95% CI 0.07-0.54; p < 0.001) as found in an exploratory analysis. Multivariate analysis also showed that prior response to ramucirumab and a taxane was an independent prognostic factor of OS with third-line CPI.

CONCLUSIONS

Response to ramucirumab and a taxane as a second-line treatment is an important prognostic marker for OS with subsequent third-line CPI. This data might provide useful information when applying CPIs as third-line therapies in advanced gastric cancer patients.

CDH1 mutations in gastric cancers are not associated with family history

CDH1 mutation is the most frequent genetic alteration in hereditary diffuse gastric cancer (GC) and early onset diffuse GC patients. However, the incidence of CDH1 mutations in sporadic GC with or without family history has not been studied. This retrospective study includes a total of 993 Korean patients with primary advanced GC who underwent surgery and received palliative chemotherapy. Targeted deep sequencing was performed in all cases and family history of GC was searched with survival analysis. We found CDH1 alterations in 146 of 993 patients (14.7 %) and 8 were germline (0.8 %). Out of 146 patients with CDH1 mutations, 25 (17.1 %) had a family history of GC in one of their first relatives, and 12 patients (8.2 %) were diagnosed with familial GC (FGC). All cases with FGC were diffuse type by Lauren classification, and only one harbored a previously reported germline mutation of CDH1 (c.2638 G > A) and the remaining 11 harbored known somatic CDH1 mutations. Among all patients with CDH1 mutation, there was no significant survival difference between patients with family history or FGC. In the 847 patients without CDH1 mutation, 189 (22.3 %) had a family history of GC and 92 patients (10.9 %) were FGC. CDH1 mutations were more frequent in patients with early onset (<45 years) GC (45.5 %) compared with patients with late onset GC (10.9 %) (p = 0.001), but were not significantly associated with the family history of GC (p > 0.05). CDH1 mutations are mostly somatic and typically are not associated with family history.