The construction work on 141-143 Harley Street, which will house Advanced Oncotherapy PLC's (LON:AVO) first clinical proton therapy system, has just been completed. The project first kicked off in 2015. How, in your opinion, does proton therapy fit into the Harley Street Medical Area?
When the Howard de Walden Estate began to formulate its long-term plan for the Harley Street Medical Area (HSMA) several years ago our primary aim was a simple one: to attract both the best technology and consultants available. We have worked tirelessly to build up the reputation of HSMA as an internationally renowned centre of excellence in medicine. Today over 5,000 practitioners with various specialties practice in Harley Street, which puts HSMA at the forefront of medicine.
Proton therapy as the state-of-the-art treatment for cancer naturally fits into our concept for HSMA. It efficiently destroys cancer cells and at the same time it is less harmful than conventional radiotherapy to the healthy tissue surrounding the tumour. This is the kind of modern, individualised therapy that we want to make available on Harley Street.
It is also important to us that patients coming to the Harley Street Medical Area be able to receive a complete range of treatments in the very heart of London. To this end, we encourage cooperation between the various healthcare providers in our area. With proton therapy, Advanced Oncotherapy brings into the area an important treatment option for the oncologists practicing in Harley Street.
You partnered with Advanced Oncotherapy back in 2015, to equip the first proton therapy centre in HSMA. What attracted you to their LIGHT proton therapy system?
Installing any other conventional proton beam therapy system in a residential area in the centre of London would simply be impossible.
Those systems consist of a cyclotron, a 2-3m diameter, 90-tonne particle accelerator that accelerates protons to their maximum energy. These are then led through a series of electromagnets before reaching a degrader which ‘dumps’ excess energy before it reaches the patient. All these components generate a lot of unwanted radiation and traditional facilities require concrete walls up to 6m thick in order to shield the environment. In the centre of London there is not enough space to build such a facility. And we wouldn’t take the risk to put a machine with so much stray radiation in a densely populated area.
With the LIGHT system, Advanced Oncotherapy has developed a solution to these problems. The heart of the system is a linear accelerator, where energy can be modulated in the accelerator. No excess energy is generated, which means that the shielding requirements are radically reduced.
Additionally, LIGHT is a modular design and each of its components can be delivered through a specialist bed lift. There is no need for cranes or any other heavy machinery to install and maintain the system.
Finally, to deliver protons from the right angle, proton beam therapy units use gantries that can be up to 10m in diameter and can weigh up to 200 tonnes. In Advanced Oncotherapy’s system the patient is instead positioned in a robotic chair which moves the patient as necessary to gain the best access to the tumour.
Together with Advanced Oncotherapy, we have put a lot of effort to optimise the use of the space available so that patients can receive proton therapy close to their home and are spared from travelling long distances.
What was especially challenging about building a proton therapy centre in the middle of London?
The challenges were manifold. First, there was the question of how to put the accelerator in this confined space.
When we began the project, it was just a standard medical refurbishment of 141 Harley Street and 29 Devonshire Mews West. When Advanced Oncotherapy came on board with their client, the project boundary grew to include 143 Harley Street and 28 Devonshire Mews West. The two mews buildings and the links to the front buildings were demolished and a deep basement to host the accelerator was excavated. A solution had to be found not only to align the 4 buildings, but also to prevent any damage to the interior and exterior of the two listed front buildings.
Even with the 2 additional mews buildings, the length of the accelerator hall located at basement level was restricted by the listing and façade of 141 Harley Street and in the rear by the electrical substation that is accessible from Devonshire Mews West. To maximize the space for the accelerator, the treatment room has been moved one storey down and protons will be delivered through a bent beamline.
The LIGHT system requires very accurate cooling. All areas below ground also require comfort cooling and mechanical ventilation. Hence, most of the mews houses and the space above the treatment space within the 143 Harley Street demise are dedicated to plant.
Which consequences does this construction have on the residents of the area?
In the long run, none. That is except for the fact, that if they ever need it, they will have the possibility to be treated with protons just around the corner. As mentioned before, the shielding requirements for Advanced Oncotherapy’s system are minimal and both the accelerator and the treatment rooms are situated below the ground.
Of course, the project consulted with local residents on various neighbours’ consultation evenings, meetings one on one with individual neighbours, and meetings with Ward Councillors and the local amenity society.
We also went to significant lengths to minimise the nuisance involved with the construction & excavations work. One way we were able to reduce this was to keep the Mews road free of any & all construction vehicles and machinery.
To minimize any noise during construction, all work was carried out within Westminster City Council’s stipulated hours of operations, based on a 2 hours on/ 2 hours off basis.
The buildings in Harley Street 141 and 143 are Grade II listed. How does one fit a modern medical centre into a historic site?
Almost the entire Howard de Walden Estate falls within a zone known as the Harley Street Conservation Area, which is subject to highly restrictive planning regulations. We at Howard de Walden Estate are proud of the rich heritage of this area and committed to the preservation of its exceptional character.
In order to obtain listed building consent for the works to two listed buildings, we needed to explain to Westminster City Council the benefit and strategic importance that this cutting edge technology would bring to central London and the Harley Street Medical Area.
The creation of a 21st century facility within an 18th century building is a hugely demanding and specialised task. Over the years, we have developed a wealth of experience and expertise relating to the upkeep of listed buildings. Today the Harley Street Medical Area hosts hospitals and clinics specialising in the most demanding areas of medicine.
Our approach to the proton therapy centre was to preserve as much of the original interior as possible, while also constructing a building that will meet the very high standards set out for a radiotherapy unit. The interior of the two listed buildings fronting onto Harley Street remained unchanged. In agreement with the Westminster City Council Planners, who also insisted that we reinstate the configuration of the backyards once the excavation and construction work was complete. The backyards as well as the mews are mainly dedicated to ventilation of the accelerator and the underground rooms. We have therefore screened the cooling and ventilation system behind windows and under the pavement.
The result is impressive. The Harley Street proton beam therapy centre fits under and within a listed house.
What was your personal experience from working on this project?
This is obviously a big project with its own unique challenges. However, once this exciting project is completed, it will bring significant value to our Estate and to the local community and further strengthens our reputation as both an innovator and preserver of listed building. What makes me even prouder is the fact that we have been able to support Advanced Oncotherapy in its endeavours of making proton therapy more widely accessible to all and not just the lucky few. This spirit of partnership and support are essential because so much remains to be done to eradicate cancer and it is the responsibility of all of us to help make this happen. I am really excited to see patients being treated on this site, especially paediatric patients, whose lives can be substantially improved with this innovative and specialised form of radiation treatment.