According to a study published in Health Technology Assessment, there is little evidence to support the use of PET-CT add-on imaging device in the pre-operative staging of bowel cancer.

Over one million people are diagnosed with colorectal cancer worldwide each year, making it the third most common cancer in the UK after lung and breast cancer.

The extent of the cancer can be examined in several diagnostic tests, including ultrasound, MRI scanning (magnetic resonance imaging) computerized tomography (CT scans) and contrast enhance CT scans to scan chest, abdomen and pelvis in addition to a full blood count and biochemical profile.

These tests provide all information required before surgical resection. The type and timing of the treatment depends on how far the disease has progressed with respect to scheduling the surgery. The combination of extensive diagnoses and disease progression form the basis for accurate pre-operative scheduling.

The study evaluated existing evidence on the accuracy of diagnoses and the therapeutic impact of adding a CT in combination with Positron Emission Tomography. Computed Tomography (FDG PET-CT) scanning is the latest imaging technology utilized for pre-operative classification of colorectal cancer to their existing diagnostic tests.

The research was funded by the National Institute for Health Research Health Technology Assessment (NIHR HTA) program and led by Professor David Weller of the University of Edinburgh.

The results showed that using FDG PET-CT technology in the pre-operative staging of primary, recurrent and spreading of colorectal cancer resulted in limited evidence in support of this technology.

In a communiqué, the publishers of Health Technology Assessment wrote:

“Even though researchers observed that FDG PET-CT changes patient management, the data proved to be divergent with the quality of the studied research being generally poor.”

Studies revealed inconsistent results about the effectiveness that FDG PET-CT had on surgical management. The published research evaluating FDG PET-CT for primary and recurrent bowel colorectal cancer currently does not reflect routine UK clinical practice.

The researchers established that FDG PET-CT is cost-effective as an additional imaging device in the pre-operative staging of recurrent colon, recurrent rectal and metastatic disease, however, it did not prove cost-effective for primary colon or primary rectal cancers.

Professor Weller said:

“There is uncertainty about the value of using FDG PET-CT in the treatment of bowel colorectal cancer. Importantly, practitioners who access this imaging technology need to routinely collect data to enable audits of patient outcomes, including detection rate and any changes in management resulting from its use.”

Written by Petra Rattue