Epidermal growth factor receptor (EGFR) inhibitors remain a cornerstone in the treatment of metastatic colorectal cancer with RAS and BRAF wild-type cancer. Yet, primary and acquired resistance limit their benefit for many patients. A growing body of evidence reveals that resistance is not random but rather driven by a complex network of molecular alterations that sustain tumor growth independent of EGFR signaling. These include amplification of ERBB2 (HER2) and MET, activation of the PI3K and AKT pathways, EGFR extracellular domain mutations, and rare kinase fusions. The concept of negative hyperselection has emerged as a powerful strategy to refine patient selection by excluding tumors with these resistance drivers. Multiple clinical trials have consistently shown that patients who are hyperselected based on comprehensive molecular profiling achieve significantly higher response rates and improved survival compared to those selected by RAS and BRAF status alone. Liquid biopsy through circulating tumor DNA has further transformed this landscape, offering a noninvasive tool to capture tumor heterogeneity, monitor clonal evolution in real time, and guide rechallenge strategies after resistance emerges. Together, negative hyperselection, ctDNA-guided monitoring, and emerging therapeutics define a precision-oncology framework for identifying, tracking, and overcoming resistance to anti-EGFR therapy in mCRC, moving the field toward more effective and individualized care. Looking ahead, the development of innovative therapeutics such as bispecific antibodies, antibody drug conjugates, and RNA-based therapies promises to further expand in this challenging clinical scenario. These advances move precision oncology in colorectal cancer from concept to clinical reality, reshaping the standard of care through molecular insights.

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.

Liver cancer is the third most common cause of cancer-related mortality worldwide, with over 780,000 deaths in 2018. About 90% of liver cancer cases are hepatocellular carcinoma (HCC), a prototype ... Plain language summary Liver cancer is the third most common cause of cancer-related mortality worldwide, with over 780,000 deaths in 2018. About 90% of liver cancer cases originate in liver cells ... Tweetable abstract The HIMALAYA study illustrates the value of the STRIDE regimen. One single dose of anti-CTLA4 tremelimumab plus durvalumab demonstrated an overall survival benefit for patients i...

Background: The benefit of adding Zolbetuximab to the treatment in patients with Claudin-18 isoform 2 (CLDN18.2)-positive, human epidermal growth factor receptor 2-negative, locally advanced unresectable or metastatic gastric or gastro-oesophageal junction adenocarcinoma (GC/GEJ) is not yet fully elucidated. Methods: We searched PubMed, Embase and Cochrane databases for randomized controlled trials (RCTs) that investigated Zolbetuximab plus chemotherapy versus chemotherapy alone for GC or GEJ adenocarcinoma. We computed hazard-ratios (HRs) or odds-ratios (ORs) for binary endpoints, with 95% confidence intervals (CIs). Results: Three studies and 1,233 patients were included. Comparing with Zolbetuximab plus chemotherapy versus chemotherapy alone, progression-free survival (PFS) rate (HR 0.64; 95% CI 0.49–0.84; p < 0.01) and overall survival (OS) rate (HR 0.72; 95% CI 0.62–0.83; p < 0.01) were significant in favor of the Zolbetuximab group. Regarding effectiveness, the Objective Response Rate (ORR) was (OR 1.15; 95% CI 0.87–1.53; p = 0.34). Conclusions: In this comprehensive systematic review and meta-analysis of RCTs, the incorporation of Zolbetuximab alongside chemotherapy offers a promising prospect for reshaping the established treatment paradigms for patients diagnosed with advanced CLDN18.2-positive GC/GEJ cancer.