Synchronous Colorectal Cancer Epidemiology and Management

Synchronous colorectal cancer (SCRC) is defined by the simultaneous presence of two or more primary tumours in the colon or rectum at initial diagnosis. It accounts for approximately 3–8 per cent of all colorectal malignancies and poses distinctive challenges in detection, staging and treatment planning. Epidemiological analyses show higher incidence in older patients and a slight male predominance, with a predilection for the left colon in certain populations. Tumour multiplicity often reflects independent clonal origins, resulting in marked interlesional heterogeneity in genetic alterations, methylation patterns and immune microenvironments. This complexity underpins variable treatment responses and highlights the necessity for comprehensive perioperative surveillance, including high‐resolution imaging and full colonic evaluation. Management requires a multidisciplinary strategy that integrates surgical resection—ranging from segmental colectomy to subtotal colectomy for bilateral disease—with tailored adjuvant therapy driven by molecular profiling. Recognition of field effects and germline susceptibility factors further informs risk stratification, surveillance intervals and family counselling. Collectively, these insights support an individualised approach aiming to optimise oncological outcomes and preserve quality of life.

Research from Nature Portfolio

Recent studies have illuminated the genetic and immunological foundations of SCRC. Analyses of paired synchronous lesions reveal that each tumour often arises independently, acquiring distinct somatic mutations and clonal architectures. A higher burden of rare damaging germline variants in immune‐related genes has been identified in patients with multiple primary tumours, accompanied by altered immune cell compositions within both tumour and adjacent mucosa. These findings suggest an inflammatory field effect that predisposes to multicentric tumourigenesis and may modulate response to immune‐based therapies. Recognition of this heterogeneity emphasises the need to characterise each lesion genetically and immunologically to inform personalised treatment combinations and resistance monitoring strategies.

Synchronous Colorectal Cancer Epidemiology and Management publication trend

The graph below shows the total number of articles in synchronous colorectal cancer epidemiology and management across all publications each year (not limited to Nature Index journals).

Technical terms

Synchronous colorectal cancer (SCRC): Two or more primary colorectal tumours detected simultaneously or within six months of the first diagnosis.

Germline mutation: A heritable alteration in DNA present in the egg or sperm that can predispose to cancer.

Microsatellite instability (MSI): A condition of genetic hypermutability caused by defective mismatch repair, leading to insertion or deletion errors in short tandem repeats.

CpG island methylator phenotype (CIMP): A subset of cancers characterised by widespread hypermethylation of CpG islands in gene promoter regions.

Mismatch repair (MMR): A cellular process that corrects base–base mismatches and insertion–deletion loops arising during DNA replication.

References

1. Patients with genetically heterogeneous synchronous colorectal cancer carry rare damaging germline mutations in immune-related genes. Nature Communications (2016).
2. Multiple Sporadic Colorectal Cancers Display a Unique Methylation Phenotype. PLOS ONE (2014).
3. A 10-Year Evaluation of Short-Term Outcomes After Synchronous Colorectal Cancer Surgery: a Dutch Population-Based Study. Journal of Gastrointestinal Surgery (2021).
4. Synchronous Colorectal Cancer: Improving Accuracy of Detection and Analyzing Molecular Heterogeneity—The Main Keys for Optimal Approach. Diagnostics (2021).
5. RAS mutations vary between lesions in synchronous primary Colorectal Cancer: Testing only one lesion is not sufficient to guide anti-EGFR treatment decisions.. Oncoscience (2015).