CONSERVE: a Feasibility Study for a Multicentre Randomised Controlled Trial to Compare Surgery (Partial Nephrectomy) With Needle Ablation Techniques (Radiofrequency Ablation/Cryotherapy) for the Treatment of People With Small Renal Masses (4cm)
This study will be a multicentre study to determine if it is possible to carry out a future
trial comparing the effectiveness of two minimally invasive techniques to remove small
kidney cancers, with the standard treatment of removing part of the diseased kidney. In this
future study, participants will be randomly assigned (randomised) to one of these three
treatment options. This current study will look at whether patients would be willing to be
randomised to a treatment type, whether sufficient numbers for a larger trial would be
likely to be recruited within a certain time period, and also to decide what aspects of the
conduct and outcomes of each of the three treatment types would need to be recorded in a
largescale trial to compare their effectiveness.
Eligible participants for this study will be identified and will be invited to take part in
the study by their clinicians currently involved in their kidney cancer assessment. They
would then receive information about the surgery treatment (removing the diseases part of
the kidney) and one of the alternative treatment methods (destroying the kidney cancer
tumour using either heat or by freezing) in the participating hospital. If the patient was
interested in participating in the study, they will be asked to consent to be randomised to
one of the two treatment types they were given the information about.
If a patient declines to be randomised to a treatment, they will be asked to participate in
a series of interviews, to establish the reasons behind why they declined, such as if they
had a preference for one of the treatments.
Those patients that consent to being randomised to one of the treatment arms will undergo a
screening visit to confirm their eligibility for this study, and at this visit they will
have a blood sampke taken and be asked to complete some questionnaires about their general
health and how they feel. This is so that any questionnaires completed at a later date after
treatment will be compared to how the patient responded before treatment, in order to look
for any changes or improvements to the patients. Once they have been confirmed as eligible,
they will be randomised to a treatment arm,, and a hospital appointment for their treatment
will also be made at this time.
At the treatment visit, each patient will be admitted to hospital for their treatment as
scheduled, and will be kept in hospital for the recommended duration after their operation.
Those having the diseased part of the kidney removed will be kept in hospital for 35 days,
those having their kidney cancer frozen using cryoablation will be kept in hospital for 2
days, and those having their kidney cancers destroyed using heat (radiofrequency ablation)
will be kept in for one day.
As per standard care, this duration of time in hospital could vary if the patient
experiences any unexpected complications. They will also have some blood samples taken at
this visit to assess their kidney function.
All treatments will be given by a qualified specialist surgeon with extensive experience in
the treatment they are giving the patient.
Three months after their treatment, each patient will be asked to return to their hospital
for a followup visit. At this visit, the patients will be asked to complete the same
questionnaires as was completed previously, as well as to undertake a CT scan to assess if
the treatment they were given was successful and to determine if all the kidney cancer was
removed or destroyed. This CT scan is for patients who undergo cryoablaton treatment only.
Patients who undergo radiofrequency ablation treatment will have a CT scan one month after
treatment. All patients will also have a blood sample taken at this visit to assess their
Six months after their treatment, each patient will be asked to return to their hospital for
a followup visit, at which point patients undergoing cryoablation treatment will once again
have a CT scan to assess if their treatment remains a success, and to determine if all the
kidney cancer is still destroyed or whether some of it has returned. They will be asked to
complete the questionnaires from previous visits one more time, so as to compare how they
feel and how their general health has improved or changed from previously.
Patients who undergo radiofrequency ablation treatment or cryoablation treatment will be
required to attend for a further final visit within 2 weeks of their 6 month followup visit
in order to have a kidney biopsy taken to determine if their treatment remains a success and
all of the cancer mass has been destroyed.
After these six months, and five visit, the patient will return to their normal standard
clinical followup visits, which they would be having whether they were on the study or not.
As well as these mentioned visits, some patients who consent to be randomised, will also be
asked to consent to being involved in a series of interviews, at which times they will be
asked general questions on how they feel in general and about the treatments they have
Allocation: Randomized, Intervention Model: Parallel Assignment, Masking: Open Label
The proportion of patients who agree to trial registration and accept randomisation
To estimate the proportion of patients with renal masses < 4cm who agree to trial registration and accept randomisation to either partial nephrectomy or one of the ablative techniques
Newcastle upon Tyne Hospitals NHS Foundation Trust
United Kingdom: Medicines and Healthcare Products Regulatory Agency