Colorectal Cancer Blood testing

After undergoing surgery for colorectal cancer that has begun to spread, many patients traditionally move on to chemotherapy. This helps to minimise the risk of the cancer reoccurring elsewhere in the body.

However, until recently, there was no reliable method to determine who truly needed this additional treatment and who didn’t. New research has found a simple blood test could be all that’s needed to determine which patients require post surgical chemotherapy.

Read on to discover more about this promising discovery and the colorectal cancer treatment options available.

Could a blood test predict the need for chemotherapy?

The recent research discovered the significant role of circulating tumour DNA (ctDNA) in the need for chemotherapy. These are fragments of genetic material shed by tumours into the bloodstream.

The study found that patients with positive ctDNA tests who received chemotherapy, experienced longer periods without the cancer returning compared to those who did not undergo chemotherapy. On the other hand, a negative ctDNA test pinpointed patients who likely could forgo immediate post-surgical chemotherapy, as it didn’t notably prolong their time without cancer recurrence.

Among the 623 study participants, 381 began chemotherapy roughly three months following their surgery. This was guided by the degree of abnormality in the cancer cells removed during the operation, alongside other risk factors.

Out of these, 85 patients with a positive ctDNA result saw a substantial benefit from chemotherapy, achieving a median disease-free survival time of almost 18 months. This was in contrast to about 7 months for those with positive ctDNA who skipped chemotherapy.

However, for those with a negative ctDNA test, the effect of chemotherapy on extending disease-free survival was minimal, with more than 90% living over two years without their cancer reoccurring, irrespective of receiving chemotherapy.

Many patients currently undergo unnecessary chemotherapy

Many patients could currently be undergoing unnecessary chemotherapy, facing its severe side effects without experiencing any substantial benefits. The ctDNA blood test could be a game-changer, helping avoid needless chemotherapy and the associated physical and emotional toll the treatment takes on the mind and body.

This tailored approach to postoperative care allows for a better understanding of individual cancer recurrence risks. By pinpointing who truly needs adjuvant therapy, healthcare providers can ensure that treatment is not only effective, but also empathetic. It can minimise the burden on patients and optimise their quality of life during and after cancer treatment.

Treating colorectal cancer: What are your options?

Treatment options for colorectal cancer include surgical and non-surgical methods. Surgical approaches for colon cancer include keyhole surgery and single incision bowel removal.

For rectal cancer, options extend to keyhole surgery, single incision rectal removal, and trans anal endoscopic microsurgery (TEMS) for early-stage cancers, which is less invasive and offers quicker recovery.

Advanced or recurrent cancers may require more extensive procedures like pelvic exenteration or intraoperative radiotherapy to mitigate the risk of recurrence. Hyperthermic intraperitoneal chemotherapy (HIPEC) is another innovative method, delivering heated chemotherapy directly to the abdomen during surgery.

Non-surgical treatments are considered when colon or rectal cancer is very small and removed during colonoscopy, or when surgery poses too great a risk due to the patient’s health. Some rectal cancers may vanish after chemotherapy and radiotherapy, leading to a ‘watch and wait’ strategy, though future surgery might still be necessary.

Professor Jamie Murphy provides both surgical and non-surgical treatments for colorectal cancer. To determine which treatment option is the most suitable for you, schedule an appointment today.