The study, which is being led by Tom Cave, the team of pathologists at the Veterinary Pathology Group (VPG) Histology and Jonathan Bray from Fitzpatrick Referrals, will be the largest piece of research into canine soft tissue sarcoma (STS) tumours to date. The research will look at what happened to over 15,000 dogs with STS after surgery to remove their tumour.
STS is one of the most common malignant tumours in dogs. It can metastasize and is especially prone to local recurrence if surgery fails to completely remove it. Unlike some tumours, these problems may take over two years to develop.
Tom commented: “to study STS you need to allow a long follow-up time to fully understand the outcome of treatment. With some tumours you can revisit the patient one year on and understand what happened, but with STS you need to continue follow-up for at least two to three years or you risk overestimating the success of treatment.”
STSs vary widely in their potential to cause problems after surgery, and this can lead to uncertainty on the dose of surgery required and the need for adjuvant treatments like radiotherapy and chemotherapy. Current assessments like tumour grade and surgical margins are used to help formulate a treatment plan but are imperfect and the efficacy of some adjuvant treatments like metronomic chemo is still uncertain. Jonathan commented: “there is some evidence that these types of treatment are of help and this has become an accepted option – but it doesn’t mean that there is unequivocal evidence that it’s effective”. All of this leads to uncertainty over the dose of surgery required and the need for follow on assessment and treatment. Tom commented: “this means that there is real potential that we are under or over-treating dogs for one of the most common tumours we see in practice”.
That is the objective of the study. In the largest multi-practice oncology study to be conducted to date, Tom, Jonathan and the team of pathologists at VPG will revisit over 15,000 STS cases spread over 13 years which have been submitted from 783 UK, Irish and Scandinavian practices to discover the outcome for these patients.
Over the coming weeks and months, Tom and Jonathan will be reaching out to practices to ask for their help to fill in the missing blanks in the database of STS patients. Previous studies of this type looked at up to 350 cases, so the team hope that the massive surge in scale will lead to more confidence in conclusions and the treatment recommendations they inform. But they cannot do it without the help of the submitting practices.
In the coming weeks vets at submitting practices will receive an email from the team requesting information be returned using an online web-based form. Tom and Jonathan acknowledge that the study will not succeed without the valuable time and assistance from colleagues in practice but “currently, we’re all sitting in consulting rooms talking to clients about what to do without all of the required information. With the veterinary community’s help, we can start to remedy this for all of us, our clients, and most importantly of all, our patients.”
Using the results the team hope to better identify which tumours need more investigation and treatment in terms of clinical staging, duration of follow up, surgical dose and adjuvant therapies. Tom continued: “but it isn’t just enough to tell if further treatment is indicated we also need to confirm if it is effective”. So another one of the aims of the study is to look for evidence of treatment efficacy.
In addition to traditional assessments like tumour grade and surgical margins they also plan to assess the role of next generation tumour DNA sequencing. They hope that the DNA signature of STSs will better predict their subsequent behaviour.
Jonathan commented: “The long-term objective is that the DNA signature becomes available as a pre-diagnostic test. Its future gazing, but that’s where we want to be, having quality data on what the biology of the tumour is before we operate. We currently work in reverse, undertaking expensive surgery without the insight we need. We need to move from hindsight to foresight and this is a first step in heading towards that.”
Backed by VPG’s Managing Director Fiona Gosling, the VPG team hope that this will be the first of several studies to make use of the Group’s high-quality database. They also hope to start recruiting prospective cohorts of patients to confirm findings from retrospective studies with the ultimate aim of then facilitating prospective treatment trials.
VPG histology currently diagnoses over 1,000 STSs per year for practices. Tom commented: “I support colleagues in practice with advice on difficult internal medicine and oncology cases as a consultant for VPG. But I am incredibly fortunate to have also been supported in a role at VPG to help pursue clinical research. I’ve always wanted to do this but lacked the time when I ran my busy clinical referral practice. I’d like to initiate studies but also to facilitate them with partners in practice who have research ideas they want to follow.”
Tom and Jonathan both want to undertake research with the goal of improving clinical practice and patient outcomes. They commented “Over the next 10 years, it’s our aim to leave the profession better informed than we found it”.
For more information on the STS study, readers are invited to contact Tom via an email.