By Dr Angela George, Consultant Medical Oncologist and Consultant in Oncogenetics at The Royal Marsden
As oncologists, we owe it to every patient to give them the best possible treatment for their cancer, and I believe one of the most reliable ways to do this is through comprehensive genomic profiling. Circulating tumour DNA (ctDNA) liquid biopsy testing is transforming cancer care by delivering faster diagnoses and truly personalised treatment options.
Faster molecular diagnosis
For many patients, the traditional diagnostic pathway can be challenging. Tissue biopsies may not be suitable for patients who are unwell, extremely painful in those with bone-only metastases and often yield insufficient samples for comprehensive molecular profiling. Certain cancers, like pancreatic or bile duct tumours or lesions located near blood vessels, may be difficult to biopsy and often require multiple invasive attempts, prolonging the time to diagnosis and treatment. CtDNA testing can overcome these challenges by providing a safe and fast diagnostic solution, helping patients start treatment sooner and improving outcomes.
At The Royal Marsden, our Marsden360 liquid biopsy test can provide actionable molecular information from a single blood sample, with results in under 10 days. For lung cancer, the turnaround can be as short as five days, significantly speeding up the diagnostic pathway.
This speed isn’t just about efficiency; it’s about providing patients with an effective option. Recently, a patient presented acutely ill with imaging suggestive of advanced lung cancer. Previously, he might have been referred to palliative care as he was not fit for invasive diagnostics, but with the Marsden360, we were able to identify an EGFR mutation, and targeted treatment was started within two weeks. This case demonstrates the value of ctDNA beyond standard diagnostics.
Molecularly matched treatment
CtDNA testing also allows us to offer a personalised, tailored treatment approach with molecularly matched therapies. This is particularly valuable for those with relapsed or metastatic disease, as treatment can be selected based on specific changes present in a patient’s tumour cells.
This impact extends across multiple cancer types. For example, in ER-positive metastatic breast cancer progressing on endocrine treatment, detecting ESR1 or PIK3CA mutations can guide precise treatment decisions. For metastatic prostate cancer with bone-only metastases, identifying a BRCA mutation can guide suitability for PARP inhibitors, and in cancers of unknown primary, molecular profiling can help establish the likely tissue of origin.
Supporting clinical decision-making
CtDNA is reshaping our approach to complex cancers. For some patients, it is the fastest and sometimes only route to a definitive diagnosis, allowing us to deliver the right treatment at the right time.
Marsden360 offers a well-established, comprehensive service that provides both diagnostic results and clinician support. Our expert-led molecular tumour board helps interpret complex genomic findings and translates them into targeted, more informed treatment decisions.
The Marsden360 test is now available for private patients. To learn more about how Marsden360 can support your practice, visit our Marsden360 video FAQ hub or contact us today.
