Encorafenib, cetuximab and chemotherapy in BRAF-mutant colorectal cancer: a randomized phase 3 trial.

Encorafenib + cetuximab (EC) is approved for previously treated BRAF V600E-mutant metastatic colorectal cancer (mCRC) based on the BEACON phase 3 study. Historically, first-line treatment of BRAF V600E-mutant mCRC with chemotherapy regimens has had limited efficacy. The phase 3 BREAKWATER study investigated EC+mFOLFOX6 versus standard of care (SOC) in patients with previously untreated BRAF V600E mCRC.

Correlation Between Grade of Clinical Response to Neoadjuvant Therapy for Rectal Cancer and Oncologic Outcomes in the Era of Watch-and-Wait.

Background: The watch-and-wait strategy provides an opportunity to pursue non-operative management in rectal cancer patients with clinical complete response after neoadjuvant therapy. The management of those with near complete response remains controversial.

Objective: We assessed the oncologic outcomes of patients managed by watch-and-wait versus total mesorectal excision according to clinical response to neoadjuvant therapy.

A phase I dose-escalation study of LRP5/6 antagonist BI 905677 in patients with advanced solid tumors.

Background: Aberrant Wnt pathway signaling has been implicated in the development of many cancers. Targeting of low-density lipoprotein receptor-related protein 5/6 (LRP5/6) co-receptors inhibits Wnt signaling and may be a novel therapy. BI 905677 is an LRP5/6 antagonist that has demonstrated preclinical antitumor activity.

Analysis of Shared Variants between Cancer Biospecimens.

Purpose: Mutational data from multiple solid and liquid biospecimens of a single patient are often integrated to track cancer evolution. However, there is no accepted framework to resolve if individual samples from the same individual share variants due to common identity versus coincidence.

Experimental Design: Utilizing 8,000 patient tumors from The Cancer Genome Atlas across 33 cancer types, we estimated the background rates of co-occurrence of mutations between discrete pairs of samples across cancers and by cancer type.

Evidence for Unified Assessment Criteria of HER2 Immunohistochemistry in Colorectal Carcinoma.

Human epidermal growth factor receptor-2 (HER2) expression is an important biomarker for the management of RAS wild-type metastatic colorectal carcinoma (CRC). Immunohistochemistry (IHC) with reflex in situ hybridization (ISH) is accepted as a standard method of assessment, yet there are currently the following 2 sets of criteria used to interpret results: the HER2 Amplification for Colorectal Cancer Enhanced Stratification (HERACLES) criteria and the MyPathway criteria. The HER2 Amplification for Colorectal Cancer Enhanced Stratification criteria require ISH confirmation when IHC staining is 3+ in 10% to 49% of cells, whereas the MyPathway criteria mirror those for gastric HER2 assessment and do not recommend ISH confirmation in the previously referenced scenario.

Progressive plasticity during colorectal cancer metastasis.

As cancers progress, they become increasingly aggressive-metastatic tumours are less responsive to first-line therapies than primary tumours, they acquire resistance to successive therapies and eventually cause death. Mutations are largely conserved between primary and metastatic tumours from the same patients, suggesting that non-genetic phenotypic plasticity has a major role in cancer progression and therapy resistance. However, we lack an understanding of metastatic cell states and the mechanisms by which they transition.

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.

Molecular profiling of BRAF-V600E-mutant metastatic colorectal cancer in the phase 3 BEACON CRC trial.

The BEACON CRC study demonstrated that encorafenib (Enco)+cetuximab (Cetux)±binimetinib (Bini) significantly improved overall survival (OS) versus Cetux + chemotherapy in previously treated patients with BRAF-V600E-mutant mCRC, providing the basis for the approval of the Enco+Cetux regimen in the United States and the European Union. A greater understanding of biomarkers predictive of response to Enco+Cetux±Bini treatment is of clinical relevance. In this prespecified, exploratory biomarker analysis of the BEACON CRC study, we characterize genomic and transcriptomic correlates of clinical outcomes and acquired resistance mechanisms through integrated clinical and molecular analysis, including whole-exome and -transcriptome tissue sequencing and circulating tumor DNA genomic profiling.

Organ preservation after neoadjuvant long-course chemoradiotherapy versus short-course radiotherapy.

Background: Potential differences in organ preservation between total neoadjuvant therapy (TNT) regimens integrating long-course chemoradiotherapy (LCCRT) and short-course radiotherapy (SCRT) in rectal cancer remain undefined.

Patients And Methods: This natural experiment arose from a policy change in response to the COVID-19 pandemic during which our institution switched from uniformly treating patients with LCCRT to mandating that all patients be treated with SCRT. Our study includes 323 locally advanced rectal adenocarcinoma patients treated with LCCRT-based or SCRT-based TNT from January 2018 to January 2021.

Molecular and Clinicopathologic Impact of GNAS Variants Across Solid Tumors.

Purpose: The molecular drivers underlying mucinous tumor pathogenicity are poorly understood. mutations predict metastatic burden and treatment resistance in mucinous appendiceal adenocarcinoma. We investigated the pan-cancer clinicopathologic relevance of variants.

A Classical Epithelial State Drives Acute Resistance to KRAS Inhibition in Pancreatic Cancer.

Intratumoral heterogeneity in pancreatic ductal adenocarcinoma (PDAC) is characterized by a balance between basal and classical epithelial cancer cell states, with basal dominance associating with chemoresistance and a dismal prognosis. Targeting oncogenic KRAS, the primary driver of pancreatic cancer, shows early promise in clinical trials, but efficacy is limited by acquired resistance. Using genetically engineered mouse models and patient-derived xenografts, we find that basal PDAC cells are highly sensitive to KRAS inhibitors.

Tumor-Agnostic Genomic and Clinical Analysis of BRAF Fusions Identifies Actionable Targets.

Purpose: Even though BRAF fusions are increasingly detected in standard multigene next-generation sequencing panels, few reports have explored their structure and impact on clinical course.

Experimental Design: We collected data from patients with BRAF fusion-positive cancers identified through a genotyping protocol of 97,024 samples. Fusions were characterized and reviewed for oncogenic potential (in-frame status, non-BRAF partner gene, and intact BRAF kinase domain).

Immune checkpoint inhibitors for POLE or POLD1 proofreading-deficient metastatic colorectal cancer.

Background: POLE and POLD1 proofreading deficiency (POLE/D1pd) define a rare subtype of ultramutated metastatic colorectal cancer (mCRC; over 100 mut/Mb). Disease-specific data about the activity and efficacy of immune checkpoint inhibitors (ICIs) in POLE/D1pd mCRC are lacking and it is unknown whether outcomes may be different from mismatch repair-deficient (dMMR)/microsatellite instability-high (MSI-H) mCRCs treated with ICIs.

Patients And Methods: In this global study, we collected 27 patients with mCRC harboring POLE/D1 mutations leading to proofreading deficiency and treated with anti-programmed cell death-ligand 1 alone +/- anti-cytotoxic T-lymphocyte antigen-4 agents.

Early-onset Colorectal Cancer Patients Do Not Require Shorter Intervals for Post-surgical Surveillance Colonoscopy.

Background & Aims: Early-onset colorectal cancer (EO-CRC), diagnosed before age 50, is rising in incidence worldwide. Although post-surgical colonoscopy surveillance strategies exist, appropriate intervals in EO-CRC remain elusive, as long-term surveillance outcomes remain scant. We sought to compare findings of surveillance colonoscopies of EO-CRC with patients with average onset colorectal cancer (AO-CRC) to help define surveillance outcomes in these groups.

Precision medicine for pancreatic cancer: characterizing the clinicogenomic landscape and outcomes of KRAS G12C-mutated disease.

Background: Mutated Kirsten rat sarcoma viral oncogene homolog (KRAS) is the most common oncogene alteration in pancreatic ductal adenocarcinoma, and KRAS glycine to cystine substitution at codon 12 (G12C) mutations (KRAS G12Cmut) are observed in 1%-2%. Several inhibitors of KRAS G12C have recently demonstrated promise in solid tumors, including pancreatic cancer. Little is known regarding clinical, genomics, and outcome data of this population.

Tumorigenesis driven by the BRAF oncoprotein requires secondary mutations that overcome its feedback inhibition of migration and invasion.

mutation occurs in 46% of melanomas and drives high levels of ERK activity and ERK-dependent proliferation. However, is insufficient to drive melanoma in GEMM models, and 82% of human benign nevi harbor mutations. We show here that BRAF inhibits mesenchymal migration by causing feedback inhibition of RAC1 activity.

Efficacy and Safety of Adagrasib plus Cetuximab in Patients with KRASG12C-Mutated Metastatic Colorectal Cancer.

Unlabelled: Adagrasib, an irreversible, selective KRASG12C inhibitor, may be an effective treatment in KRASG12C-mutated colorectal cancer, particularly when combined with an anti-EGFR antibody. In this analysis of the KRYSTAL-1 trial, patients with previously treated KRASG12C-mutated unresectable or metastatic colorectal cancer received adagrasib (600 mg twice daily) plus cetuximab. The primary endpoint was objective response rate (ORR) by blinded independent central review.