A new technique that delivers high doses of radiation to tumours while sparing the surrounding normal tissue shows promise as a curative treatment option for patients with early-stage liver cancer, according to researchers.

Curative treatment options for early-stage hepatocellular carcinoma (HCC), the most common type of liver cancer, include surgery, liver transplantation, and radiofrequency ablation. Radiation segmentectomy is a minimally invasive option that uses the radioisotope yttrium-90 (Y90) to destroy tumours. Radiation segmentectomy performed on an outpatient basis is minimally invasive and has a low toxicity profile, said Riad Salem, chief of vascular interventional radiology at the Northwestern University Feinberg School of Medicine in Chicago, the US.

Using an imaging approach called cone beam CT, interventional radiologists gain a detailed view of the complex liver vasculature and can focus delivery of the Y90 to the relevant segment. The results, published in the journal Radiology, showed that radiation segmentectomy controlled the target tumour, slowed the time to disease progression and improved survival outcomes at rates comparable to radiofrequency ablation, surgery, and transplantation for early-stage HCC patients.

"Cone beam CT has revolutionised our ability to perform segmental injections isolated to very small tumours, sparing the majority of normal tissue," Salem said. "Before cone beam CT, we had the ability to focus radiation, but not with this level of accuracy," Salem added. For the study, the team analysed long-term outcomes in nearly 100 early-stage HCC patients who had undergone radiation segmentectomy between 2003 and 2016.

Almost three-quarters of patients had no progression of cancer in the target tumour five years after treatment. Median overall survival was 6.7 years, and one, three, and five-year survival probabilities were 98 per cent, 66 per cent and 57 per cent, respectively. "Our numbers with radiation segmentectomy match or outperform those of other curative treatments in terms of tumour control, survival rate and recurrence," Salem said.