New technique from Cambridge cancer researchers will enable fewer, more targeted tumour biopsies
Cancer researchers in Cambridge have developed an advanced computing technique using routine medical scans that could enable doctors to take fewer, but more accurate, tumour biopsies.
They have combined CT (computed tomography) scans with ultrasound images to create a visual guide for medics that enables them to use more targeted biopsies to sample the full complexity of a tumour.
One day the technique could even allow clinical biopsies to be replaced with virtual biopsies, to spare patients invasive procedures.
The research was led by Professor Evis Sala, from the Department of Radiology, co-lead of the Cancer Research UK Cambridge Centre’s advanced cancer imaging programme, who said: “This study provides an important milestone towards precision tissue sampling. We are truly pushing the boundaries in translating cutting-edge research to routine clinical care.”
Most cancer patients undergo one or several biopsies in order to capture their tumour’s heterogeneity - that is the full genetic variety of cells within it.
Understanding this is key for selecting the best treatment, as genetically different cells may respond differently to therapies.
Reducing the number of these biopsies, and ensuring they accurately sample the different cells is therefore crucial, particularly for ovarian cancer patients.
High grade serous ovarian (HGSO) cancer is the most common type of ovarian cancer and referred to as a ‘silent killer’ because its early symptoms can be hard to pick up. Survival rates have not improved much in 20 years.
HGSO tumours also have a high level of heterogeneity - and we know that patients with more genetically-different patches cancer cells tend to have poorer responses to treatment.
Prof Sala leads a multi-disciplinary team of radiologists, physicists, oncologists and computational scientists using innovative computing techniques to reveal tumour heterogeneity from standard medical images.
The new study involved a small group of patients with advanced ovarian cancer, who were due to have ultrasound-guided biopsies prior to starting a course of chemotherapy.
Patients in the study first had a standard CT scan, which uses X-rays and computing to create a 3D image of the tumour, by taking multiple image ‘slices’ through the body.
The process of radiomics, which uses high-powered computing to analyse and extract additional information from the data-rich CT scan images, was then used to identify and map distinct areas and features of the tumour.
The researchers then superimposed the ultrasound image of the tumour and the combined image - which successfully captured the diversity of cancer cells - was used to guide the biopsy procedure.
Co-first author Dr Lucian Beer, from the Department of Radiology and CRUK Cambridge Centre ovarian cancer programme, said: “Our study is a step forward to non-invasively unravel tumour heterogeneity by using standard-of-care CT-based radiomic tumour habitats for ultrasound-guided targeted biopsies.”
Co-first author Paula Martin-Gonzalez, also from the programme, added: “We will now be applying this method in a larger clinical study.”
The study was welcomed by Fiona Barve, 56, a science teacher living near Cambridge, who was diagnosed with stage 4 ovarian cancer in 2017 after visiting her doctor with abdominal pain. She immediately underwent surgery and chemotherapy and has been cancer-free since March 2019.
Fiona, who is now back to teaching three days a week, said: “I was diagnosed at a late stage and I was fortunate my surgery, which I received within four weeks of being diagnosed, and chemotherapy worked for me. I feel lucky to be around.
“When you are first undergoing the diagnosis of cancer, you feel as if you are on a conveyor belt, every part of the journey being extremely stressful. This new enhanced technique will reduce the need for several procedures and allow patients more time to adjust to their circumstances. It will enable more accurate diagnosis with less invasion of the body and mind. This can only be seen as positive progress.”
The feasibility study involved researchers from the Department of Radiology, CRUK Cambridge Institute, Addenbrooke’sl, Cambridge University Hospitals NHS Foundation Trust and collaborators at Cannon, and was facilitated through the CRUK Cambridge Centre Integrated Cancer Medicine programme.
The progamme’s aim is to revolutionise cancer treatment using the integration of complex patient data from multiple sources – blood tests, biopsies, medical imaging, and genetic tests – to inform and predict the best treatment decisions for each individual.
The study was funded by Cancer Research UK and The Mark Foundation for Cancer Research.