Conventional radiotherapy for the treatment of lung cancer commonly requires the patient to lie down on their back, while the 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 tumour stays within the target area despite this extra movement.
Research
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 patients with lung cancer 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.
This particular study showed that breathing motion was on average up to 5mm less in the upright orientation. With less motion we can consider reducing treatment margins due to increased tumour stability. Smaller treatment margins will result in a less irradiation of healthy tissue.
Easier breathing can alleviate anxiety by disrupting the cycle of stress-induced shallow breathing. Stress hormones can spike heart rate and constrict airways, leading to faster, inefficient breathing and lowered oxygen levels, potentially triggering panic attacks. Upright positions allowing greater lung volumes can break this cycle, reducing panic in patients.