A study to see if a new type of CT scan can help improve radiotherapy outcomes for non small cell lung cancer

Cancer type:

Lung cancer

Non small cell lung cancer

Status:

Results

Phase:

Pilot

This study looked at ‘4D’ CT scanning to see if it could show non small cell lung cancer (NSCLC) even more accurately than current CT scans.

If your non small cell lung cancer cannot be removed with surgery, you may have radical radiotherapy Open a glossary item . Doctors use CT scans to plan radiotherapy treatment. But because your chest moves when you breathe, it is difficult to scan the exact position and shape of lung cancer. Doctors need to make sure that the radiotherapy reaches the whole cancer whether you are breathing in or out. They do this by also treating some healthy tissue just beyond the edge of the cancer. But this can cause a side effect called radiation pneumonitis.

Doctors are starting to use a new type of CT scan that allows for lung cancer movement caused by breathing. The 4D CT scan takes pictures throughout your breathing cycle. Doctors may be able to use these pictures to give radiotherapy to the lung more accurately, and so protect more healthy tissue.

The aim of this study was to see how much healthy lung tissue doctors treated if they planned radiotherapy with a 4D CT scan.

Summary of results

The study team found that using 4D CT scan could improve radiotherapy treatment for people with non small cell lung cancer.

This was a pilot study. It recruited 10 people who all had their radiotherapy treatment planned using the standard 3D CT scan. For 7 people, it was possible to compare the standard plans with plans made using 4D CT scans. 3 doctors made separate 4D CT plans. It was shown that there was better agreement between the doctors when using the 4D CT scan compared with the standard images. Also, the planned target volume was significantly smaller for the 4D CT plans.

The researchers also compared 4 different ways of calculating the target volume from the 4D CT scan. They found that 1 way was much better than the others for planning radiotherapy.

The researchers also compared the doses of radiotherapy to the cancer and the surrounding healthy tissue when using the 4D CT scan and the 3D CT scan. They found that there was a smaller dose of radiotherapy to the healthy tissue using the 4D CT scan.

The team concluded that using the 4D CT scan to plan radiotherapy for people with non small cell lung cancer can reduce the amount of radiotherapy to the surrounding healthy tissue.

We have based this summary on information from the team who ran the trial. The information they sent us has been reviewed by independent specialists (peer reviewed Open a glossary item ) but may not have been published in a medical journal. The figures we quote above were provided by the trial team. We have not analysed the data ourselves.