EGFR-directed antibodies promote HER2 ADC internalization and efficacy.

Trastuzumab deruxtecan (T-DXd) is a human epidermal growth factor receptor 2 (HER2)-targeting antibody drug conjugate that has remarkable activity in HER2-positive cancers. However, the degree of benefit of T-DXd is not uniform among solid tumors even with high levels of HER2. Despite high HER2 expression, the HER2/T-DXd complex may not always undergo internalization and payload release dependent on the receptor's conformation and context. We hypothesize that epidermal growth factor receptor (EGFR), a dimerization partner of HER2, can modulate HER2 trafficking through endocytic pathways and affect T-DXd uptake. We demonstrate that elevated EGFR expression levels can promote EGFR/HER2 heterodimer formation and suppress T-DXd internalization and efficacy. Knockdown of EGFR expression or pharmacologic stimulation of EGFR endocytosis with EGFR monoclonal antibodies restores T-DXd trafficking and antitumor activity in EGFR-overexpressing cancers in vivo. Our results reveal EGFR overexpression to be a potential mechanism of resistance to T-DXd, which can be overcome by combination therapy strategies targeting EGFR.

Genomic Landscape of Adenocarcinomas Across the Gastroesophageal Junction: Moving on from the Siewert Classification.

OBJECTIVE: To investigate how the Siewert classification of gastroesophageal junction adenocarcinomas correlates with genomic profiles. SUMMARY/BACKGROUND DATA: Current staging and treatment guidelines recommend that tumors with an epicenter less than 2 cm into the gastric cardia be treated as esophageal cancers, while tumors with epicenter greater than 2 cm into the cardia be staged and treated as gastric cancers. To date, however, few studies have compared the genomic profiles of the 3 Siewert classification groups to validate this distinction. METHODS: Using targeted tumor sequencing data on patients with adenocarcinoma of the gastroesophageal junction previously treated with surgery at our institution, we compared genomic features across Siewert classification groups. RESULTS: A total of 350 patients were included: 121 had Siewert type I, 170 type II, and 59 type III. Comparisons by Siewert location revealed that Siewert type I and II were primarily characterized as the chromosomal instability (CIN) molecular subtype and displayed Barrett's metaplasia and p53 and cell cycle pathway dysregulation. Siewert type III tumors, by contrast, were more heterogeneous, including higher proportions of microsatellite instability (MSI) and genomically stable (GS) tumors and more frequently displayed ARID1A and somatic CDH1 alterations, signet ring cell features, and poor differentiation. Overall, Siewert type I and II tumors demonstrated greater genomic overlap with lower esophageal tumors, while Siewert type III tumors shared genomic features with gastric tumors. CONCLUSIONS: Overall, our results support recent updates in treatment and staging guidelines. Ultimately, however, molecular rather than anatomic classification may prove more valuable in determining staging, treatment, and prognosis.

Patient metabolic profile defined by liver and muscle 18F-FDG PET avidity is independently associated with overall survival in gastric cancer.

BACKGROUND: PET-CT-based patient metabolic profiling is a novel concept to incorporate patient-specific metabolism into gastric cancer care. METHODS: Staging PET-CTs, demographics, and clinicopathologic variables of gastric cancer patients were obtained from a prospectively maintained institutional database. PET-CT avidity was measured in tumor, liver, spleen, four paired muscles, and two paired fat areas in each patient. The liver to rectus femoris (LRF) ratio was defined as the ratio of SUVmean of liver to the average SUVmean of the bilateral rectus femoris muscles. Kaplan-Meier and Cox-proportional hazards models were used to identify the impact of LRF ratio on OS. RESULTS: Two hundred and one patients with distal gastroesophageal (48%) or gastric (52%) adenocarcinoma were included. Median age was 65 years, and 146 (73%) were male. On univariate analysis, rectus femoris PET-CT avidity and LRF ratio were significantly associated with overall survival (p < 0.05). LRF ratio was significantly higher in males, early-stage cancer, patients with an ECOG 0 or 1 performance status, patients with albumin > 3.5 mg/dL, and those with moderately differentiated tumor histology. In multivariable regression, gastric cancer stage, albumin, and LRF ratio were significant independent predictors of overall survival (LRF ratio HR = 0.73 (0.56-0.96); p = 0.024). Survival curves showed that the prognostic impact of LRF was associated with metastatic gastric cancer (p = 0.009). CONCLUSIONS: Elevated LRF ratio, a patient-specific PET-CT-based metabolic parameter, was independently associated with an improvement in OS in patients with metastatic gastric cancer. With prospective validation, LRF ratio may be a useful, host-specific metabolic parameter for prognostication in gastric cancer.

18F-BMS-986229 PET to Assess Programmed-Death Ligand 1 Status in Gastroesophageal Cancer.

Anti-programmed death 1 (PD-1) inhibitors are the standard of care for advanced gastroesophageal cancer. Although recommendations and approval by regulatory agencies are often based on programmed death ligand 1 (PD-L1) expression, pathologic assessments of PD-L1 status have several limitations. Single-site biopsies do not adequately capture disease heterogeneity within individual tumor lesions or among several lesions within the same patient, the PD-L1 combined positive score is a dynamic biomarker subject to evolution throughout a patient's disease course, and repeated biopsies are invasive and not always feasible. Methods: This was a prospective pilot study of the PD-L1-targeting radiotracer, 18F-BMS-986229, with PET imaging (PD-L1 PET) in patients with gastroesophageal cancer. Patients were administered the 18F-BMS-986229 radiotracer intravenously at a dose of 370 MBq over 1-2 min and underwent whole-body PET/CT imaging 60 min later. The primary objective of this study was to evaluate the safety and feasibility of 18F-BMS-986229. The trial is registered with ClinicalTrials.gov (NCT04161781). Results: Between February 3, 2020, and February 2, 2022, 10 patients with gastroesophageal adenocarcinoma underwent PD-L1 PET. There were no adverse events associated with the 18F-BMS-986229 tracer, and imaging did not result in treatment delays; the primary endpoint was achieved. Radiographic evaluation of PD-L1 expression was concordant with pathologic assessment in 88% of biopsied lesions, and 18F-BMS-986229 uptake on PET imaging correlated with pathologic evaluation by the combined positive score (Spearman rank correlation coefficient, 0.64). Seventy-one percent of patients with 18F-BMS-986229 accumulation on PET imaging also had lesions without 18F-BMS-986229 uptake, highlighting the intrapatient heterogeneity of PD-L1 expression. Patients treated with frontline programmed death 1 inhibitors who had 18F-BMS-986229 accumulation in any lesions on PET imaging had longer progression-free survival than patients without tracer accumulation in any lesions (median progression-free survival, 28.4 vs. 9.9 mo), though the small sample size prevents any definitive conclusions. Conclusion: PD-L1 PET imaging was safe, feasible, and concordant with pathologic evaluation and offers a potential noninvasive tool to assess PD-L1 expression.

First-Line Nivolumab Plus Chemotherapy for Advanced Gastric, Gastroesophageal Junction, and Esophageal Adenocarcinoma: 3-Year Follow-Up of the Phase III CheckMate 649 Trial.

Clinical trials frequently include multiple end points that mature at different times. The initial report, typically based on the primary end point, may be published when key planned co-primary or secondary analyses are not yet available. Clinical Trial Updates provide an opportunity to disseminate additional results from studies, published in JCO or elsewhere, for which the primary end point has already been reported.We report 3-year efficacy and safety results from the phase III CheckMate 649 trial. Patients with previously untreated advanced or metastatic gastroesophageal adenocarcinoma were randomly assigned to nivolumab plus chemotherapy or chemotherapy. Primary end points were overall survival (OS) and progression-free survival (PFS) by blinded independent central review (BICR) in patients whose tumors expressed PD-L1 combined positive score (CPS) ≥5. With 36.2-month minimum follow-up, for patients with PD-L1 CPS ≥5, the OS hazard ratio (HR) for nivolumab plus chemotherapy versus chemotherapy was 0.70 (95% CI, 0.61 to 0.81); 21% versus 10% of patients were alive at 36 months, respectively; the PFS HR was 0.70 (95% CI, 0.60 to 0.81); 36-month PFS rates were 13% versus 8%, respectively. The objective response rate (ORR) per BICR was 60% (95% CI, 55 to 65) with nivolumab plus chemotherapy versus 45% (95% CI, 40 to 50) with chemotherapy; median duration of response was 9.6 months (95% CI, 8.2 to 12.4) versus 7.0 months (95% CI, 5.6 to 7.9), respectively. Nivolumab plus chemotherapy also continued to show improvement in OS, PFS, and ORR versus chemotherapy in the overall population. Adding nivolumab to chemotherapy maintained clinically meaningful long-term survival benefit versus chemotherapy alone, with an acceptable safety profile, supporting the continued use of nivolumab plus chemotherapy as standard first-line treatment for advanced gastroesophageal adenocarcinoma.

Immunotherapy for Resectable Locally Advanced Esophageal Carcinoma.

BACKGROUND: The current standard of care for locally advanced esophageal and gastroesophageal junction (GEJ) cancers includes neoadjuvant chemoradiotherapy or perioperative chemotherapy with surgical resection; however, disease-free survival in these patients remains poor. Immune checkpoint inhibitors (ICIs) are approved for adjuvant treatment of locally advanced esophageal and GEJ cancers, but their benefit in the perioperative and neoadjuvant settings remains under investigation. METHODS: We used the PubMed online database to conduct a literature search to identify studies that investigated immunotherapy for locally advanced esophageal and GEJ carcinoma. A review of ClinicalTrials.gov yielded a list of ongoing trials. RESULTS: Adjuvant nivolumab for residual disease after neoadjuvant chemoradiotherapy and surgery is the only approved immunotherapy regimen for locally advanced esophageal cancer. Early-phase trials investigating the addition of neoadjuvant or perioperative ICIs to standard-of-care multimodality approaches have observed pathologic complete response rates as high as 60%. Response rates are highest for ICIs plus chemoradiotherapy for esophageal squamous cell carcinoma and dual checkpoint inhibition in mismatch repair-deficient adenocarcinomas. Safety profiles are acceptable, with a pooled adverse event rate of 27%. Surgical morbidity and mortality with immunotherapy are similar to historical controls with no immunotherapy, and R0 resection rates are high. When reported, disease-free survival among patients treated with perioperative immunotherapy is promising. CONCLUSIONS: Outside of clinical trials, immunotherapy for resectable esophageal carcinoma is limited to the adjuvant setting. Phase III trials investigating neoadjuvant and perioperative immunotherapy are now underway and will provide much-needed data on survival that may ultimately lead to practice-changing recommendations.

Clinical and molecular characteristics of early-onset vs average-onset esophagogastric cancer.

BACKGROUND: The rate of esophagogastric cancer is rising among individuals under 50 years of age. It remains unknown whether early-onset esophagogastric cancer represents a unique entity. This study investigated the clinical and molecular characteristics of early-onset and average-onset esophagogastric cancer . METHODS: We reviewed the Memorial Sloan Kettering Cancer Center gastric, esophageal, and gastroesophageal junction cancer database. Associations between baseline characteristics and tumor and germline molecular alterations were compared between those with early-onset and average-onset esophagogastric cancer using Fisher exact tests and the Benjamini-Hochberg method for multiple-hypothesis correction. RESULTS: We included 1123 patients with early-onset esophagogastric cancer (n = 219; median age = 43 years [range = 18-49 years]) and average-onset esophagogastric cancer (n = 904; median age = 67 years [range = 50-94 years]) treated between 2005 and 2018. The early-onset group had more women (39% vs 28%, P = .002). Patients with early-onset esophagogastric cancer were more likely to have a gastric primary site (64% vs 44%, P < .0001). The signet ring cell and/or diffuse type was 3 times more common in the early-onset esophagogastric cancer group (31% vs 9%, P < .0001). Early-onsite tumors were more frequently genomically stable (31% vs 18%, P = .0002) and unlikely to be microsatellite instability high (2% vs 7%, P = .003). After restricting to adenocarcinoma and signet ring cell and/or diffuse type carcinomas, we observed no difference in stage (P = .40) or overall survival from stage IV diagnosis (median = 22.7 vs 22.1 months, P = .78). CONCLUSIONS: Our study supported a preponderance of gastric primary disease sites, signet ring histology, and genomically stable molecular subtypes in early-onset esophagogastric cancer. Our findings highlight the need for further research to define the underlying pathogenesis and strategies for early detection and prevention.

Neoadjuvant and adjuvant pembrolizumab plus chemotherapy in locally advanced gastric or gastro-oesophageal cancer (KEYNOTE-585): an interim analysis of the multicentre, double-blind, randomised phase 3 study.

BACKGROUND: The benefit of combination neoadjuvant and adjuvant chemotherapy and immune checkpoint inhibition in patients with locally advanced, resectable gastric or gastro-oesophageal adenocarcinoma is unknown. We assess the antitumor activity of neoadjuvant and adjuvant pembrolizumab plus chemotherapy in patients with locally advanced resectable gastric or gastro-oesophageal adenocarcinoma. METHODS: The KEYNOTE-585 study is a multicentre, randomised, placebo-controlled, double-blind, phase 3 study done at 143 medical centres in 24 countries. Eligible patients were aged 18 years or older with untreated, locally advanced, resectable gastric or gastro-oesophageal adenocarcinoma, and an Eastern Cooperative Oncology Group performance status 0-1. Patients were randomly assigned (1:1) by an interactive voice response system and integrated web response system to neoadjuvant pembrolizumab 200 mg intravenously or placebo (saline) plus cisplatin-based doublet chemotherapy (main cohort) every 3 weeks for 3 cycles, followed by surgery, adjuvant pembrolizumab or placebo plus chemotherapy for 3 cycles, then adjuvant pembrolizumab or placebo for 11 cycles. A small cohort was also randomly assigned (1:1) to pembrolizumab or placebo plus fluorouracil, docetaxel, and oxaliplatin (FLOT)-based chemotherapy (FLOT cohort) every 2 weeks for four cycles, followed by surgery, adjuvant pembrolizumab, or placebo plus FLOT for four cycles, then adjuvant pembrolizumab or placebo for 11 cycles. Patients were stratified by geographic region, tumour stage, and chemotherapy backbone. Primary endpoints were pathological complete response (reviewed centrally), event-free survival (reviewed by the investigator), and overall survival in the intention-to-treat population, and safety assessed in all patients who received at least one dose of study treatment. The study is registered at ClinicalTrials.gov, NCT03221426, and is closed to accrual. FINDINGS: Between Oct 9, 2017, and Jan 25, 2021, of 1254 patients screened, 804 were randomly assigned to the main cohort, of whom 402 were assigned to the pembrolizumab plus cisplatin-based chemotherapy group and 402 to the placebo plus cisplatin-based chemotherapy group, and 203 to the FLOT cohort, of whom 100 were assigned to the pembrolizumab plus FLOT group and 103 to placebo plus FLOT group. In the main cohort of 804 participants, 575 (72%) were male and 229 (28%) were female. In the main cohort, after median follow-up of 47·7 months (IQR 38·0-54·8), pembrolizumab was superior to placebo for pathological complete response (52 [12·9%; 95% CI 9·8-16·6] of 402 vs eight [2·0%; 0·9-3·9] of 402; difference 10·9%, 95% CI 7·5 to 14·8; p<0·00001). Median event-free survival was longer with pembrolizumab versus placebo (44·4 months, 95% CI 33·0 to not reached vs 25·3 months, 20·6 to 33·9; hazard ratio [HR] 0·81, 95% CI 0·67 to 0·99; p=0·0198) but did not meet the threshold for statistical significance (p=0·0178). Median overall survival was 60·7 months (95% CI 51·5 to not reached) in the pembrolizumab group versus 58·0 months (41·5 to not reached) in the placebo group (HR 0·90, 95% CI 0·73 to 1·12; p=0·174). Grade 3 or worse adverse events of any cause occurred in 312 (78%) of 399 patients in the pembrolizumab group and 297 (74%) of 400 patients in the placebo group; the most common were nausea (240 [60%] vs 247 [62%]), anaemia (168 [42%] vs 158 [40%]), and decreased appetite (163 [41%] vs 172 [43%]). Treatment-related serious adverse events were reported in 102 (26%) and 97 (24%) patients. Treatment-related adverse events that led to death occurred in four (1%) patients in the pembrolizumab group (interstitial ischaemia, pneumonia, decreased appetite, and acute kidney injury [n=1 each]) and two (<1%) patients in the placebo group (neutropenic sepsis and neutropenic colitis [n=1 each]). INTERPRETATION: Although neoadjuvant and adjuvant pembrolizumab versus placebo improved the pathological complete response, it did not translate to significant improvement in event-free survival in patients with untreated, locally advanced resectable gastric or gastro-oesophageal cancer. FUNDING: Merck Sharp & Dohme.

Neoplasia risk in patients with Lynch syndrome treated with immune checkpoint blockade.

Metastatic and localized mismatch repair-deficient (dMMR) tumors are exquisitely sensitive to immune checkpoint blockade (ICB). The ability of ICB to prevent dMMR malignant or pre-malignant neoplasia development in patients with Lynch syndrome (LS) is unknown. Of 172 cancer-affected patients with LS who had received ≥1 ICB cycles, 21 (12%) developed subsequent malignancies after ICB exposure, 91% (29/32) of which were dMMR, with median time to development of 21 months (interquartile range, 6-38). Twenty-four of 61 (39%) ICB-treated patients who subsequently underwent surveillance colonoscopy had premalignant polyps. Within matched pre-ICB and post-ICB follow-up periods, the overall rate of tumor development was unchanged; however, on subgroup analysis, a decreased incidence of post-ICB visceral tumors was observed. These data suggest that ICB treatment of LS-associated tumors does not eliminate risk of new neoplasia development, and LS-specific surveillance strategies should continue. These data have implications for immunopreventative strategies and provide insight into the immunobiology of dMMR tumors.

Pembrolizumab plus trastuzumab and chemotherapy for HER2-positive gastric or gastro-oesophageal junction adenocarcinoma: interim analyses from the phase 3 KEYNOTE-811 randomised placebo-controlled trial.

BACKGROUND: Evidence for the efficacy of combined PD-1 and HER2 blockade with chemotherapy on progression-free and overall survival in HER2-positive gastro-oesophageal cancer is scarce. The first interim analysis of the randomised, phase 3 KEYNOTE-811 study showed a superior objective response with pembrolizumab compared with placebo when added to trastuzumab plus fluoropyrimidine and platinum-based chemotherapy. Here, we report results from protocol-specified subsequent interim analyses of KEYNOTE-811. METHODS: The randomised, phase 3 KEYNOTE-811 trial involved 168 medical centres in 20 countries worldwide. Patients aged 18 years or older with locally advanced or metastatic HER2-positive gastro-oesophageal junction adenocarcinoma, without previous first-line treatment, were randomly assigned (1:1) by an integrated interactive voice-response and web-response system to intravenous pembrolizumab 200 mg or placebo, both to be combined with standard chemotherapy (fluoropyrimidine and platinum-based therapy) plus trastuzumab every 3 weeks for up to 35 cycles or until disease progression, unacceptable toxic effects, or investigator or participant-initiated withdrawal. Randomisation used a block size of four and was stratified by region, PD-L1 status, and chemotherapy. Dual primary endpoints were progression-free and overall survival, analysed by intention to treat. Safety was assessed in all randomly assigned patients who received at least one dose of study treatment according to the treatment received. KEYNOTE-811 is registered with ClinicalTrials.gov (NCT03615326) and is active but not recruiting. FINDINGS: Between Oct 5, 2018, and Aug 6, 2021, 698 patients were assigned to pembrolizumab (n=350) or placebo (n=348). 564 (81%) were male and 134 (19%) were female. At the third interim analysis, 286 (82%) of 350 patients in the pembrolizumab group and 304 (88%) of 346 in the placebo group who received treatment had discontinued treatment, mostly due to disease progression. At the second interim analysis (median follow-up 28·3 months [IQR 19·4-34·3] in the pembrolizumab group and 28·5 months [20·1-34·3] in the placebo group), median progression-free survival was 10·0 months (95% CI 8·6-11·7) in the pembrolizumab group versus 8·1 months (7·0-8·5) in the placebo group (hazard ratio [HR] 0·72, 95% CI 0·60-0·87; p=0·0002). Median overall survival was 20·0 months (17·8-23·2) versus 16·9 months (15·0-19·8; HR 0·87 [0·72-1·06]; p=0·084). At the third interim analysis (median follow-up 38·4 months [IQR 29·5-44·4] in the pembrolizumab group and 38·6 months [30·2-44·4] in the placebo group), median progression-free survival was 10·0 months (8·6-12·2) versus 8·1 months (7·1-8·6; HR 0·73 [0·61-0·87]), and median overall survival was 20·0 months (17·8-22·1) versus 16·8 months (15·0-18·7; HR 0·84 [0·70-1·01]), but did not meet prespecified criteria for significance and will continue to final analysis. Grade 3 or worse treatment-related adverse events occurred in 204 (58%) of 350 patients in the pembrolizumab group versus 176 (51%) of 346 patients in the placebo group. Treatment-related adverse events that led to death occurred in four (1%) patients in the pembrolizumab group and three (1%) in the placebo group. The most common treatment-related adverse events of any grade were diarrhoea (165 [47%] in the pembrolizumab group vs 145 [42%] in the placebo group), nausea (154 [44%] vs 152 [44%]), and anaemia (109 [31%] vs 113 [33%]). INTERPRETATION: Compared with placebo, pembrolizumab significantly improved progression-free survival when combined with first-line trastuzumab and chemotherapy for metastatic HER2-positive gastro-oesophageal cancer, specifically in patients with tumours with a PD-L1 combined positive score of 1 or more. Overall survival follow-up is ongoing and will be reported at the final analysis. FUNDING: Merck Sharp & Dohme.

Impact of Helicobacter pylori infection status on outcomes among patients with advanced gastric cancer treated with immune checkpoint inhibitors.

BACKGROUND: Gut microbiota composition can influence cancer immunotherapy response. Recent evidence suggests Helicobacter pylori infection may reduce immune checkpoint inhibitor (ICI) efficacy in lung cancer and melanoma, but thorough characterization of this association in patients with gastric cancer is lacking. We aimed to determine the impact of H. pylori on survival in this population. METHODS: This single-center, retrospective study included all ICI-treated individuals with metastatic gastric cancer and documented H. pylori status at Memorial Sloan Kettering between July 2013 and October 2021. H. pylori-positive status was defined as history of infection obtained via breath test, stool antigen test, histopathology, and/or chart documentation. Negative status was defined as explicitly negative testing, histopathology, and/or chart documentation. Primary outcomes were progression-free survival (PFS) and overall survival (OS). RESULTS: Of 215 included patients, 49 had documented history of H. pylori infection. Compared with H. pylori-negative patients, positive individuals tended to be younger, non-white, and Hispanic with non-cardia and intestinal-type gastric cancer. H. pylori-positive patients had significantly shorter median PFS (3.2 vs 6.8 months, HR 1.96, p<0.01) and OS (9.8 vs 17.9 months, HR 1.54, p=0.02). Multivariable analysis confirmed H. pylori infection as an independent predictor of PFS (HR 3.04, p<0.01) and OS (HR 2.24, p=0.01). CONCLUSIONS: In this largest study of its kind, H. pylori infection was associated with inferior survival in ICI-treated patients with gastric cancer. This suggests H. pylori status may be a prognostic marker of immune responsiveness. Future studies are needed to elucidate immunoregulatory mechanisms and whether treatment of active infections would improve immunotherapy outcomes.

First-line regorafenib with nivolumab and chemotherapy in advanced oesophageal, gastric, or gastro-oesophageal junction cancer in the USA: a single-arm, single-centre, phase 2 trial.

BACKGROUND: The addition of nivolumab to chemotherapy improves survival in patients with advanced oesophagogastric (oesophageal, gastric, or gastro-oesophageal junction) adenocarcinoma; however, outcomes remain poor. We assessed the safety and activity of regorafenib in combination with nivolumab and chemotherapy in the first-line treatment of advanced oesophagogastric adenocarcinoma. METHODS: This investigator-initiated, single-arm, phase 2 trial in adult patients (aged ≥18 years) with previously untreated, HER2-negative, metastatic oesophagogastric adenocarcinoma was done at the Memorial Sloan Kettering Cancer Center (New York, NY, USA). Eligible patients had measurable disease or non-measurable disease that was evaluable (defined by Response Evaluation Criteria in Solid Tumours [RECIST] version 1.1) and Eastern Cooperative Oncology Group performance status of 0 or 1. Patients received FOLFOX chemotherapy (fluorouracil [400 mg/m2 bolus followed by 2400 mg/m2 over 48 h], leucovorin [400 mg/m2], and oxaliplatin [85 mg/m2]) and nivolumab (240 mg) intravenously on days 1 and 15, and oral regorafenib (80 mg) on days 1-21 of a 28-day cycle. Treatment was continued until disease progression (defined by RECIST version 1.1), unacceptable toxicity, or withdrawal of consent. The primary endpoint was 6-month progression-free survival in the per-protocol population (ie, all participants who received a dose of all study treatments). The regimen would be considered worthy of further investigation if at least 24 of 35 patients were progression free at 6 months. Safety was assessed in all participants who received at least one dose of any study treatment. This trial is registered with ClinicalTrials.gov, NCT04757363, and is now complete. FINDINGS: Between Feb 11, 2021, and May 4, 2022, 39 patients were enrolled, received at least one dose of study drug, and were included in safety analyses. 35 patients were evaluable for 6-month progression-free survival. Median age was 57 years (IQR 52-66), nine (26%) patients were women, 26 (74%) were men, 28 (80%) were White, and seven (20%) were Asian. At data cutoff (March 3, 2023), median follow-up was 18·1 months (IQR 12·7-20·4). The primary endpoint was reached, with 25 (71%; 95% CI 54-85) of 35 patients progression free at 6 months. Nine (26%) of 35 patients had disease progression and one (3%) patient died; the death was unrelated to treatment. The most common adverse event of any grade was fatigue (36 [92%] of 39). The most common grade 3 or 4 adverse events were decreased neutrophil count (18 [46%]), hypertension (six [15%]), dry skin, pruritus, or rash (five [13%]), and anaemia (four [10%]). Serious treatment-related adverse events occurred in ten (26%) patients, which were acute kidney injury (three [8%]), hepatotoxicity (two [5%]), sepsis (two [5%]), dry skin, pruritus, or rash (one [3%]), nausea (one [3%]), and gastric perforation (one [3%]). There were no treatment-related deaths. INTERPRETATION: Regorafenib can be safely combined with nivolumab and chemotherapy and showed promising activity in HER2-negative metastatic oesophagogastric cancer. A randomised, phase 3 clinical trial is planned. FUNDING: Bristol Myers Squibb, Bayer and National Institutes of Health/National Cancer Institute.

Health-Related Quality of Life With Nivolumab Plus Chemotherapy Versus Chemotherapy in Patients With Advanced Gastric/Gastroesophageal Junction Cancer or Esophageal Adenocarcinoma From CheckMate 649.

PURPOSE: In CheckMate 649, first-line nivolumab plus chemotherapy prolonged overall survival versus chemotherapy in patients with advanced/metastatic non-human epidermal growth factor receptor 2 (HER2)-positive gastric/gastroesophageal junction cancer (GC/GEJC) or esophageal adenocarcinoma (EAC). We present exploratory patient-reported outcomes (PROs). METHODS: In patients (N = 1,581) concurrently randomly assigned 1:1 to nivolumab plus chemotherapy or chemotherapy and in those with tumor PD-L1 expression at a combined positive score (CPS) of ≥5, health-related quality of life (HRQoL) was assessed using the EQ-5D and Functional Assessment of Cancer Therapy-Gastric (FACT-Ga), which included the FACT-General (FACT-G) and Gastric Cancer subscale (GaCS). The FACT-G GP5 item assessed treatment-related symptom burden. Longitudinal changes in HRQoL were assessed using mixed models for repeated measures in the PRO analysis population (randomly assigned patients with baseline and ≥1 postbaseline assessments). Time to symptom or definitive deterioration analyses were also conducted. RESULTS: In the PRO analysis population (n = 1,360), PRO questionnaire completion rates were mostly >80% during treatment. Patient-reported symptom burden was not increased with nivolumab plus chemotherapy versus chemotherapy. Mean improved changes from baseline were greater with nivolumab plus chemotherapy versus chemotherapy for FACT-Ga total, GaCS, and EQ-5D visual analog scale in patients with a CPS of ≥5; results were similar for the overall PRO analysis population. In CPS ≥5 and all randomly assigned populations, nivolumab plus chemotherapy reduced the risk of symptom deterioration versus chemotherapy, on the basis of FACT-Ga total score and GaCS; time to definitive deterioration was longer, and the risk of definitive deterioration in HRQoL was reduced with nivolumab plus chemotherapy across EQ-5D and most FACT-Ga measures (hazard ratio [95% CI] <1). CONCLUSION: Compared with chemotherapy alone, first-line nivolumab plus chemotherapy showed stable or better on-treatment HRQoL in patients with advanced/metastatic non-HER2-positive GC/GEJC/EAC and also showed decreased risk of definitive HRQoL deterioration.

Prognostic value of circumferential radial margin involvement in esophagectomy for esophageal cancer: a case series.

BACKGROUND: Residual tumor at the proximal or distal margin after esophagectomy is associated with worse survival outcomes; however, the significance of the circumferential resection margin (CRM) remains controversial. In this study, we sought to evaluate the prognostic significance of the CRM in patients with esophageal cancer undergoing resection. MATERIALS AND METHODS: We identified patients who underwent esophagectomy for pathologic T3 esophageal cancer from 2000 to 2019. Patients were divided into three groups: CRM- (residual tumor >1 mm from the CRM), CRM-close (residual tumor >0 to 1 mm from the CRM), and CRM+ (residual tumor at the surgical CRM). CRM was also categorized and analyzed per the Royal College of Pathologists (RCP) and College of American Pathologists (CAP) classifications. RESULTS: Of the 519 patients included, 351 (68%) had CRM-, 132 (25%) had CRM-close, and 36 (7%) had CRM+. CRM+ was associated with shorter disease-free survival [DFS; CRM+ vs. CRM-: hazard ratio (HR), 1.53 [95% CI, 1.03-2.28]; P =0.034] and overall survival (OS; CRM+ vs. CRM-: HR, 1.97 [95% CI, 1.32-2.95]; P <0.001). Survival was not significantly different between CRM-close and CRM-. After adjustment for potential confounders, CAP+ was associated with poor oncologic outcomes (CAP+ vs. CAP-: DFS: HR, 1.47 [95% CI, 1.00-2.17]; P =0.050; OS: HR, 1.93 [95% CI, 1.30-2.86]; P =0.001); RCP+ was not (RCP+ vs. RCP-: DFS: HR, 1.21 [95% CI, 0.97-1.52]; P =0.10; OS: HR, 1.21 [95% CI, 0.96-1.54]; P =0.11). CONCLUSION: CRM status has critical prognostic significance for patients undergoing esophagectomy: CRM+ was associated with worse outcomes, and outcomes between CRM-close and CRM- were similar.

Perioperative versus total neoadjuvant chemotherapy in gastric cancer.

Background: Perioperative chemotherapy is standard of care management for locally advanced gastric cancer (GC), but a substantial proportion of patients do not complete adjuvant therapy due to postoperative complications and prolonged recovery. Administration of all chemotherapy prior to surgery in the form of total neoadjuvant therapy (TNT) may optimize complete delivery of systemic therapy. Methods: We performed a retrospective review of GC patients who had surgery at Memorial Sloan Kettering Cancer Center (MSKCC) from May 2014 to June 2020. Results: One hundred and forty-nine patients were identified; 121 patients received perioperative chemotherapy and 28 patients received TNT. TNT was chosen if patients had interim radiographic and/or clinical response to treatment. Baseline characteristics were well-balanced between the two group except for chemotherapy regimen; more TNT patients received FLOT compared to the perioperative group (79% vs. 31%). There was no difference in the proportion of patients who completed all planned cycles, but TNT patients received a higher proportion of cycles containing all chemotherapy drugs (93% vs. 74%, P<0.001). Twenty-nine patients (24%) in the perioperative group did not receive intended adjuvant therapy. There was no significant difference in hospital length of stay or surgical morbidity. The overall distribution of pathologic stage was similar between the two groups. Fourteen percent of TNT patients and 5.8% of perioperative patients achieved a pathologic complete response (P=0.6). There was no significant difference in recurrence free survival (RFS) or overall survival (OS) between the TNT and perioperative groups [24-month OS rate 77% vs. 85%, HR 1.69 (95% CI: 0.80-3.56)]. Conclusions: Our study was limited by a small TNT sample size and biases inherent to a retrospective analysis. TNT appears to be feasible in a select population, without any increase in surgical morbidity.

Determinants of Survival with Combined HER2 and PD-1 Blockade in Metastatic Esophagogastric Cancer.

PURPOSE: We report updated clinical outcomes from a phase II study of pembrolizumab, trastuzumab, and chemotherapy (PTC) in metastatic esophagogastric cancer in conjunction with outcomes from an independent Memorial Sloan Kettering (MSK) cohort. PATIENTS AND METHODS: The significance of pretreatment 89Zr-trastuzumab PET, plasma circulating tumor DNA (ctDNA) dynamics, and tumor HER2 expression and whole exome sequencing was evaluated to identify prognostic biomarkers and mechanisms of resistance in patients treated on-protocol with PTC. Additional prognostic features were evaluated using a multivariable Cox regression model of trastuzumab-treated MSK patients (n = 226). Single-cell RNA sequencing (scRNA-seq) data from MSK and Samsung were evaluated for mechanisms of therapy resistance. RESULTS: 89Zr-trastuzumab PET, scRNA-seq, and serial ctDNA with CT imaging identified how pre-treatment intrapatient genomic heterogeneity contributes to inferior progression-free survival (PFS). We demonstrated that the presence of intensely avid lesions by 89Zr-trastuzumab PET declines in tumor-matched ctDNA by 3 weeks, and clearance of tumor-matched ctDNA by 9 weeks were minimally invasive biomarkers of durable PFS. Paired pre- and on-treatment scRNA-seq identified rapid clearance of HER2-expressing tumor clones with expansion of clones expressing a transcriptional resistance program, which was associated with MT1H, MT1E, MT2A, and MSMB expression. Among trastuzumab-treated patients at MSK, ERBB2 amplification was associated with improved PFS, while alterations in MYC and CDKN2A/B were associated with inferior PFS. CONCLUSIONS: These findings highlight the clinical relevance of identifying baseline intrapatient heterogeneity and serial ctDNA monitoring of HER2-positive esophagogastric cancer patients to identify early evidence of treatment resistance, which could guide proactive therapy escalation or deescalation.

Trastuzumab deruxtecan in patients in the USA and Europe with HER2-positive advanced gastric or gastroesophageal junction cancer with disease progression on or after a trastuzumab-containing regimen (DESTINY-Gastric02): primary and updated analyses from a single-arm, phase 2 study.

BACKGROUND: Approximately 15-20% of advanced gastric and gastro-oesophageal junction cancers overexpress HER2. In DESTINY-Gastric01, the HER2-targeted antibody-drug conjugate trastuzumab deruxtecan improved response and overall survival versus chemotherapy in patients from Japan and South Korea with locally advanced or metastatic HER2-positive gastric or gastro-oesophageal junction cancer whose disease progressed after two lines of previous therapy including trastuzumab. Here, we report primary and updated analyses of the single-arm, phase 2 DESTINY-Gastric02 trial, which aimed to examine trastuzumab deruxtecan in patients living in the USA and Europe. METHODS: DESTINY-Gastric02 is a single-arm, phase 2 study in adult patients from 24 study sites in the USA and Europe (Belgium, Spain, Italy, and the UK). Eligible patients were aged at least 18 years and had an Eastern Cooperative Oncology Group performance status of 0 or 1, pathologically documented unresectable or metastatic gastric or gastro-oesophageal junction cancer, progressive disease on or after first-line therapy with a trastuzumab-containing regimen, with at least one measurable lesion per Response Evaluation Criteria in Solid Tumours (version 1.1), and centrally confirmed HER2-positive disease on a postprogression biopsy. Patients were given 6·4 mg/kg of trastuzumab deruxtecan intravenously every 3 weeks until disease progression, withdrawal by patient, physician decision, or death. The primary endpoint was confirmed objective response rate by independent central review. The primary endpoint and safety were assessed in the full analysis set (ie, participants who received at least one dose of study drug). Here, we report the primary analysis of this study, with a data cutoff of April 9, 2021, and an updated analysis, with a data cutoff of Nov 8, 2021. This trial is registered with ClinicalTrials.gov, NCT04014075, and is ongoing. FINDINGS: Between Nov 26, 2019, and Dec 2, 2020, 89 patients were screened and 79 were enrolled and subsequently treated with trastuzumab deruxtecan (median age 60·7 years [IQR 52·0-68·3], 57 [72%] of 79 were male, 22 [28%] were female, 69 [87%] were White, four [5%] were Asian, one [1%] was Black or African American, one [1%] was Native Hawaiian or Pacific Islander, one had missing race, and three [4%] were other races). At the primary analysis (median follow-up 5·9 months [IQR 4·6-8·6 months]), confirmed objective response was reported in 30 (38% [95% CI 27·3-49·6]) of 79 patients, including three (4%) complete responses and 27 (34%) partial responses, as assessed by independent central review. As of data cutoff for the updated analysis (median follow-up 10·2 months [IQR 5·6-12·9]), a confirmed objective response was reported in 33 (42% [95% CI 30·8-53·4]) of 79 patients, including four (5%) complete responses and 29 (37%) partial responses, as assessed by independent central review. The most common grade 3 or worse treatment-emergent adverse events were anaemia (11 [14%]), nausea (six [8%]), decreased neutrophil count (six [8%]), and decreased white blood cell count (five [6%]). Drug-related serious treatment-emergent adverse events occurred in ten patients (13%). Deaths determined to be associated with study treatment occurred in two patients (3%) and were due to interstitial lung disease or pneumonitis. INTERPRETATION: These clinically meaningful results support the use of trastuzumab deruxtecan as second-line therapy in patients with HER2-positive advanced gastric or gastro-oesophageal junction cancer. FUNDING: Daiichi Sankyo and AstraZeneca.