Is Mohs micrographic surgery more effective than wide local excision in reducing recurrence for DFSP?
Dermatofibrosarcoma protuberans (DFSP) is a rare, indolent but locally aggressive cutaneous tumour, most commonly affecting adults. The commonest site affected is the trunk, followed by extremities and then head and neck. DFSP rarely metastasises, however it has a high rate of local recurrence following wide local excision (WLE) even after apparently adequate surgical margins. There is wide variation in current surgical management of DFSP across the UK. Conventional management of DFSP has been by WLE (with variable margins ranging between 1cm to 5cm), which is reported to confer recurrence rates of as high as 60%, depending on tumour location and surgical margins used.
In contrast, treatment of DFSP using Mohs micrographic surgery (MMS), which enables 100% tumour margin control, has been reported to achieve recurrence rates up to to 8.3%. However, these data are based on retrospective and/or non-comparative studies that are heterogeneous and potentially subject to bias. There have been no randomised controlled trials comparing different surgical treatments and little robust long-term follow up data is available.
Currently there are no consensus UK guidelines for the management of DFSP.
We aim to undertake a multi-centred RCT across UK Specialist Skin Cancer Multidisciplinary Team (SSMDT) centres investigating recurrence rates at 3 years for DFSP comparing MMS and WLE. Secondary outcomes include distant metastases, patient reported outcomes, patient experience rating, cosmetic appearance, adverse events and cost-effectiveness.
Trial development team
Rubeta Matin (rubeta.matin [at] ouh.nhs.uk)
Alana Durack (alana.durack [at] addenbrookes.nhs.uk)
What are the next steps?
As a result, the UK Dermatology Clinical Trials Network (UK DCTN) DFSP Study group have collaborated with the NCRI Non-Melanoma Skin Cancer Subcommittee Group to undertake feasibility work comprising the following:
1) A national retrospective case-notes review analysing management of DFSP by SSMDTs across the UK which will inform trial design.
2) Clinician surveys to determine the broad treatment strategies used by SSMDTs and Sarcoma MDTs and to assess clinician willingness to recruit patients to this trial.
3) A patient survey to determine the patient perspective on previous treatment, to assess acceptability of our proposed trial and to guide development of the trial by identifying barriers to recruitment.
In addition, we are planning further feasibility work to investigate:
1) Disease-specific patient reported outcome measures – this will involve structured patient interviews – ethical approval will be sought for this aspect of the project. If you have any patients who have experienced DFSP and would be willing to participate in interviews, please contact firstname.lastname@example.org
2) Cost-effective analysis – this work is being carried out in conjunction with a health economist
3) Further statistical analysis of the reported literature to determine the probability of distribution effect of WLE versus MMS.
How can I contribute to the study?
1) National Retrospective Case-note review
We are undertaking a national retrospective audit designed to provide an overview of the surgical management of DFSP in the UK over the last 10 years (January 2004 – January 2014). Our aim is to establish current UK clinical practice. The numbers treated at each Trust are likely to be small (incidence in the UK is estimated to be 155 cases per annum), however the grouped data will be very informative.
We would greatly appreciate your involvement. We would recommend registering this audit with your Trust audit department to satisfy their requirements. Clinicians who contribute as the lead for their Trust for collection of data will be acknowledged with authorship on resulting publications.
We are using an Excel-based proforma to collect all the data. To register for the audit, please email Alana Durack (alana.durack [at] addenbrookes.nhs.uk) directly with your name, contact details and the Trust/Hospital you will be collecting data from and she will respond with a copy of the excel proforma and details of how to complete.
2) Clinician survey – CLOSED
We are interested in the broad treatment strategies undertaken by your SSMDT and recognise that decisions are tailored for individuals. We are therefore undertaking a clinician survey to establish willingness to randomise to an RCT.
We welcome your views and would be grateful if you could answer a short questionnaire. It should take 2-3 mins to complete.
The link to the survey is:
If you have any general comments about suggested trial design, please feel free to email Rubeta Matin directly at rubeta.matin [at] ouh.nhs.uk.
3) Patient survey – CLOSED
We are undertaking a patient survey to determine the patient perspective on participating in an RCT. This is anonymised and does not ask for any personal details. It should take 2-3 mins to complete.
Please forward this link to any patients who have experienced DFSP: https://www.surveymonkey.com/s/DFSP_Patient
How do I get involved?
We are looking for enthusiastic and motivated trainees who can act as lead clinician and liaison representing all SSMDTs across the UK. If you are interested, please feel free to contact Alana Durack (alana.durack [at] addenbrookes.nhs.uk). In addition, if you feel that you wish to join the trial development group we would welcome any enthusiastic Plastic surgeons (of any grade) with experience of clinical trials, for your input into this study.