The utility of ctDNA in colorectal cancer with peritoneal metastases

Abstract

Background The development of peritoneal metastases (PM) in patients with colorectal cancer (CRC) connotates a poor prognosis. Circulating tumour (ctDNA) is a promising tumour biomarker in the management CRC. This systematic review aimed to summarize the role of ctDNA in patients with CRC and PM. Methods Following the Preferred Reporting Items for Systematic Reviews and Meta‐analyses (PRISMA) guidelines, a systematic review of the literature until June 2022 was performed. Studies reporting on the utility of ctDNA in colorectal PM were included. A total of eight eligible studies were identified including a total of 167 patients. Results The findings from this review suggest an evolving role for ctDNA in CRC with PM. ctDNA can be isolated from both plasma and peritoneal fluid, with peritoneal fluid preferred as the liquid biopsy of choice with higher mutation detection rates. Concordance rates between tissue and plasma/peritoneal ctDNA mutation detection can vary, but is generally high. ctDNA has a potential role in monitoring anti‐EGFR treatment response and resistance, as well as in predicting future prognosis and recurrence. The detection of ctDNA in plasma of patients with isolated PM is also possibly suggestive of occult systemic disease, and patients exhibiting such ctDNA positivity may benefit from systemic treatment. Limitations to ctDNA mutation detection may include the size of peritoneal lesions, as well as the fact that PM poorly shed ctDNA. Conclusion While these findings are promising, further large‐scale studies are needed to better evaluate the utility of ctDNA in this subset of patients.

Circulating Tumor DNA and Management of Colorectal Cancer

“…Xue et al performed a systematic review on the utility of ctDNA in CRC PM, including eight studies with 167 patients. The authors not only found that ctDNA can be isolated from both plasma and peritoneal fluid, but peritoneal fluid had higher mutation detection rates and was preferred for liquid biopsy [ 40 ]. Furthermore, as compared to patients with CRC PM, patients with CRC liver metastases have higher detectable ctDNA.…”

LncRNA PCAT6 is a predictor of poor prognosis of colorectal cancer

“…Research has shown that in the advanced disease setting, data highlight the potential of circulating tumor DNA (ctDNA) levels as a prognostic marker and as an early indicator of treatment response. ctDNA assessment can complement standard tissue-based testing for molecular characterisation, with the added ability to monitor emerging mutations under the selective pressure of targeted therapy, they provide an overview of the evidence supporting the use of ctDNA in CRC ( 8 , 9 ).…”