Results of a feasiblity study for prostate treatments in the upright position

 

Studies are increasingly showing how our organs move less when we are positioned upright during radiotherapy treatment, compared to when we lie down beneath a rotating gantry for therapy. 

At Leo Cancer Care, we have seen how our Marie™ solution - with people positioned in an upright orientation during treatment as opposed to lying flat (supine) - could offer clear benefits. 

Prostate Cancers

A new study we are participating in - Anatomical Changes in the Male Pelvis between the Supine and Upright Positions: A Feasibility Study for Prostate Treatments in the Upright Position - has produced encouraging results that are recorded in a Leo Cancer Care white paper and is now published in the Journal of Applied Clinical Medical Physics (JACMP). 

In the small study, 15 volunteers were scanned lying flat with a full bladder and in the upright position with a full and empty bladder, using an Upright Fonar MRI scanner. 

Study Findings 

The Pelvic study revealed that in the upright position the: 

  • Position and shape of the prostate is not impacted significantly by changes in bladder fill; 

  • Distance between the sacrum and the anterior bladder wall is significantly smaller; 

  • Anterior-posterior length of the bladder (from the front to the back) is significantly larger; 

  • Seminal vesicles (a pair of glands found in the male pelvis) are pushed down by the bladder; 

  • Normal breathing motion does not transfer significantly to the prostate region. 

Accurate targeting 

These early indications suggest that there is less organ movement when the patient is upright, potentially facilitating more accurate targeting of treatment since smaller safety margins could be applied, 

This is important in Proton Therapy, which enables better targeting of tumours with less radiation exposure to neighbouring healthy organs or tissue. 

We have long posed the question about what happens to our internal organs when we lie supine on a bench to enter beneath a rotating gantry for radiation therapy. 

It is increasingly being recognised that when we lie down, the organs move or change shape and often into a less natural position than when we stand or are seated upright. 

Naturally Placed 

This begs the question, that if our organs are more naturally placed when we stand or sit, why isn’t such treatment - particularly the precise treatment of radiotherapy - administered more commonly in this position? 

As a result, we are delighted with the latest pending findings for prostate cancer patients receiving therapy positioned upright, and in particular because they follow on from similar results from another research study we have been involved with. 

 

Quantify Benefits 

We’ve worked hard to quantify the benefits of our technology, particularly with our research partners at Centre Léon Bérard (CLB) in Lyon in France, to assess upright positioning and immobilisation accuracy based on optical images, the setup time and comfort for our participants in pelvic positioning and repositioning.  The Centre Léon Bérard is a comprehensive cancer centre that is dedicated solely to cancer care, research and education. 

The Centre Léon Berard study set out to measure both the Inter-fractional and Intra-fractional motion in the pelvic region of 16 cancer patients undergoing treatments in the supine position using standard x-ray machines, who were, as part of a research study, placed up to three times in our upright positioner during the trial period. 

With inter-fractional motion - everything that changes or moves between treatments such as weight, patient setup or repositioning - repositioning was on average below one millimeter for pelvic tumour sites with the patient setup in the upright position. 

For intra-fractional motion - any change that takes place during treatment - there were less than one-millimeter displacements for more than 80% of the patients and under three millimeters displacements for more than 90% of patients in a 20-minute time frame, for pelvic tumour sites with the patients setup in the upright position. 

Patient Preference 

Furthermore, the study with Centre Léon Bérard – revealed that patients expressed a strong preference for the upright orientation based on how comfortable and stable they felt, as well as how easy it was to navigate getting in and out of the upright seat. 

 

The potential benefits of delivering radiation therapy to patients while upright is gaining increased attention in the medical world with studies already showing it may be better for patients. 

In addition, such solutions can be highly cost effective in terms of infrastructure and smaller equipment footprints with more compact equipment such as Leo Cancer Care’s Marie™ system for Proton Beam Therapy and patient positioning systems. 

The Leo Cancer Care products are not yet commercially available and will not treat patients until regulatory approval has been achieved.

  • S. Boisbouvier, A. Boucaud, R. Tanguy, V. Grégoire (2022) Upright patient positioning for pelvic radiotherapy treatments https://doi.org/10.1016/j.tipsro.2022.11.003

  • Niek Schreuder, Wen Hsi, John Greenhalgh, Michael Kissick, Michelle Lis, Tracy Underwood, Harry Freeman, Michael Bauer, Stephen Towe and Thomas ‘Rock’ Mackie (2022) Anatomical Changes in the Male Pelvis between the Supine and Upright Positions: A Feasibility Study for Prostate Treatments in the Upright Position (Under peer review

 
NewsSophie Towe