Classification of patients with metastatic colorectal cancer into consensus molecular subtypes into real-world: A pilot study

BACKGROUND Colorectal cancer is a complex disease with high mortality rates.Over time,the treatment of metastatic colorectal cancer(mCRC)has gradually improved due to the development of modern chemotherapy and targeted therapy regimens.However,due to the inherent heterogeneity of this condition,identifying reliable predictive biomarkers for targeted therapies remains challenging.A recent promising classification system—the consensus molecular subtype(CMS)system—offers the potential to categorize mCRC patients based on their unique biological and molecular characteristics.Four distinct CMS categories have been defined:immune(CMS1),canonical(CMS2),metabolic(CMS3),and mesenchymal(CMS4).Nevertheless,there is currently no standardized protocol for accurately classifying patients into CMS categories.To address this challenge,reverse transcription polymerase chain reaction(RT-qPCR)and next-generation genomic sequencing(NGS)techniques may hold promise for precisely classifying mCRC patients into their CMSs.AIM To investigate if mCRC patients can be classified into CMS categories using a standardized molecular biology workflow.METHODS This observational study was conducted at the University of Chile Clinical Hospital and included patients with unresectable mCRC who were undergoing systemic treatment with chemotherapy and/or targeted therapy.Molecular biology techniques were employed to analyse primary tumour samples from these patients.RT-qPCR was utilized to assess the expression of genes associated with fibrosis(TGF-βandβ-catenin)and cell growth pathways(c-MYC).NGS using a 25-gene panel(TumorSec)was performed to identify specific genomic mutations.The patients were then classified into one of the four CMS categories according to the clinical consensus of a Tumour Board.Informed consent was obtained from all the patients prior to their participation in this study.All techniques were conducted at University of Chile.RESULTS Twenty-six patients were studied with the techniques and then evaluated by the Tumour Board to determine the specific CMS.Among them,23%(n=6),19%(n=5),31%(n=8),and 19%(n=5)were classified as CMS1,CMS2,CMS3,and CMS4,respectively.Additionally,8%of patients(n=2)could not be classified into any of the four CMS categories.The median overall survival of the total sample was 28 mo,and for CMS1,CMS2,CMS3 and CMS4 it was 11,20,30 and 45 mo respectively,with no statistically significant differences between groups.CONCLUSION A molecular biology workflow and clinical consensus analysis can be used to accurately classify mCRC patients.This classification process,which divides patients into the four CMS categories,holds significant potential for improving research strategies and targeted therapies tailored to the specific characteristics of mCRC.

Liquid biopsy to detect resistance mutations against anti-epidermal growth factor receptor therapy in metastatic colorectal cancer

Colorectal cancer(CRC) is a major cause of mortality worldwide, associated with a steadily growing prevalence. Notably, the identification of KRAS, NRAS, and BRAF mutations has markedly improved targeted CRC therapy by affording treatments directed against the epidermal growth factor receptor(EGFR) and other anti-angiogenic therapies. However, the survival benefit conferred by these therapies remains variable and difficult to predict, owing to the high level of molecular heterogeneity among patients with CRC. Although classification into consensus molecular subtypes could optimize response prediction to targeted therapies, the acquisition of resistance mutations to targeted therapy is, in part, responsible for the lack of response in some patients. However, the acquisition of such mutations can induce challenges in clinical practice. The utility of liquid biopsy to detect resistance mutations against anti-EGFR therapy has recently been described. This approach may constitute a new standard in the decision algorithm for targeted CRC therapy.

在一个直肠的肿瘤和它的肺复发之间的基因错误的惹人注目的类似

We are reporting the longest disease-free interval ever published for colorectal cancer, using gene profiling to confirm the linkage of the primary and metastasis. This rare case reports on a patient with late recurrence of colorectal cancer in the lung 19 years after its initial diagnosis. We used high-resolution array CGH(aCGH) to analyze the genetic aberrations of both the primary rectal and the recurrent metastatic lung lesions. Interestingly, we found striking similarities between the two lesions, despite the 19 years disease-free interval.In addition, most of the genes that were previously reported to be associated with a high recurrence score showed copy number gains by aCGH in one or both lesions. Our findings suggest that aCGH may be a helpful tool in analyzing the origin of metastatic lesions and reflect the need for a better understanding of the characteristics of the rectal tumors with a late recurrence potential.