The Potential Benefits of Treating Lung Cancer with Radiotherapy in the Upright Position
Let’s take a deep breath and make the change
Conventional radiotherapy for the treatment of lung cancer commonly requires patients to lie down on their back, while the treatment machine and radiation rotates around them. Patients can sometimes find this challenging as breathing can be more laborious and they might suffer from shortness of breath. This can be due to side effects of the disease and the negative impact of gravity and decreased lung volume in this position.
Because clinicians know the lung moves during treatment as we breathe in and out, treatment plans are created with a larger target margin to make sure the tumor stays within the target area despite this extra movement.
In 2013, a team from the MD Anderson Cancer Center published a paper comparing lung volume and respiratory motion in supine and upright positions. Data from this article highlighted potential benefits to treating lung cancer patients in the upright orientation.
The study suggested that in the upright orientation lung volume was on average 25% larger but in some cases up to 50% larger. This paper went on to show that the increased lung volume suggested a reduction in breathing motion, due to the tidal volume of air being less with each breath.
In radiation therapy, less motion may allow clinicians to challenge the current treatment margins. This particular study showed that lung movement was on average up to 5mm less in the upright orientation. The increased lung volume and potentially reduced motion will help improve treatment accuracy, minimize target ranges and reduce irradiation to healthy tissue.
A recent study by Boisbouvier et al of patients in both an upright orientation and supine orientation indicated 100% of patients were comfortable breathing upright compared to 87% whilst lying down.