Discover cutting-edge strategies revolutionising colorectal cancer (CRC) screening, from non-invasive techniques to futuristic biomarkers, promising a new era of accessible and effective early detection.

Colorectal cancer (CRC) is a major health concern worldwide, being the second leading cause of cancer-related deaths. Early detection through screening is crucial for improving survival rates, as it allows for the treatment of precancerous lesions and early-stage cancers. This article delves into the recent advancements in CRC screening techniques, focusing on non-invasive methods, blood-based biomarkers, and imaging technologies.

Non-invasive screening methods

The faecal immunochemical test (FIT) is the most widely used non-invasive screening tool. It detects human haemoglobin in stool samples with high specificity and good sensitivity. FIT’s ease of use and low cost make it an attractive option for large-scale screening programs. However, advancements in stool-based DNA testing are providing even more sensitive options by detecting genetic and epigenetic markers associated with CRC.

Blood-based biomarkers

Blood tests for CRC screening are gaining traction due to their non-invasive nature and potential for early detection. Several blood-based tests are in various stages of evaluation, including those that detect circulating tumour DNA (ctDNA). These tests look for specific mutations in the DNA shed by cancer cells into the bloodstream. The development of multi-target stool DNA tests, which combine the detection of DNA mutations with other biomarkers, is also a significant step forward.

Imaging technologies

Imaging-based screening options, such as colon capsule endoscopy, magnetic resonance (MR) colonography, and computed tomography (CT) colonography, are emerging as viable alternatives to traditional colonoscopy. These methods are less invasive and do not require sedation. The colon capsule, for example, is a pill-sized camera that captures images of the colon as it passes through the digestive tract.

Artificial intelligence and machine learning

The integration of artificial intelligence (AI) and machine learning (ML) in CRC screening is a promising area of research. AI algorithms can analyse medical images with high accuracy, potentially identifying polyps and other abnormalities that may be missed by the human eye. ML can also help in predicting an individual’s risk of CRC by analysing large datasets and identifying patterns associated with the disease.

Microfluidic diagnostics

Microfluidic devices represent a breakthrough in CRC diagnostics. These devices can process small volumes of biological samples and integrate multiple laboratory functions on a single chip. This technology allows for the rapid and sensitive detection of CRC biomarkers, facilitating real-time monitoring of disease progression and response to treatment.

Challenges and future directions

Despite these advancements, challenges remain in CRC screening. The adoption of new technologies is often hindered by cost, accessibility, and the need for extensive validation. Moreover, the COVID-19 pandemic has led to deferred screenings, creating a backlog that needs to be addressed. As screening guidelines evolve and the recommended age for starting CRC screening is lowered, the demand for non-invasive and efficient screening options will continue to grow.

Disclaimer- The views and opinions expressed in this article are those of the author and do not necessarily reflect the official policy or position of M3 India.

About the author of this article: Dr Parag Dashatwar is a DNB gastroenterologist, who leads the department of medical gastroenterology at Olive Hospital, Hyderabad.