“This is encouraging news for liver cancer patients, especially those who also have blockage in the portal vein. While patients are not cured, their lives are extended and their quality of life is improving with yttrium-90 microsphere treatment,” said Riad Salem, director of interventional oncology at Northwestern University at Northwestern Memorial Hospital, Chicago, USA. He spoke on the topic “yttrium-90 radioembolisation for hepatocellular carcinoma: Comprehensive analysis of long-term outcomes in 291 patients”.
“This unique interventional radiology treatment, which combines the radioactive isotope Y-90 into microspheres that deliver radiation directly to a tumour, is a particularly elegant way to give patients a cancer treatment that does not harm the healthy cells. Patients do not feel sick or have many of the side-effects that take place with standard cancer treatments,” added Salem, an interventional radiologist and professor of radiology, medicine and surgery.
In a 291-patient study, patients with Child-Pugh A disease, with or without portal vein thrombosis, benefitted the most from Y-90 treatment, said Salem, with some patients surviving more than 20 months. Child-Pugh A patient with branch portal vein thrombosis survived nearly 17 months. “These are early promising results. This information can be used to design future Y-90 trials and to describe Y-90 as a potential treatment option to liver cancer patients,” he added.
Liver cancer treatment options are limited, said Salem. Although surgical removal of liver tumours offers the best chance for a cure, it is not possible for more than three-fourths of primary liver cancer patients. Liver tumours are often inoperable because the tumour may be too large or have grown into major blood vessels or other vital structures. Sometimes many small tumours are spread throughout the liver, making surgery too risky or impractical.
Historically, chemotherapy drugs and external radiation therapy have been ineffective at curing inoperable liver cancer. Additionally, due to the compromised liver function of liver cancer patients, physicians must be careful that cancer treatments do not cause additional liver damage and toxicity, which could lead to death.
“For these patients, minimally invasive treatments offer them an option that can give them more time,” said Salem. Y-90 treatment adds to interventional radiology’s nonsurgical advances for liver cancer, such as delivering chemotherapy directly to the affected organ (chemoembolisation), radiofrequency ablation or cryoablation to treat cancer locally.
Combining the radioactive isotope Y-90 into microspheres to deliver radiation directly to a tumour allows for a higher, local dose of radiation to be used and since Y-90 radiates from within and, since it is administered via the hepatic artery, it can be viewed as “internal” radiation, said Salem. Y-90 treatment is approved by the Food and Drug Administration for the treatment of unresectable hepatocellular carcinoma.
In the study, 291 patients with hepatocellular carcinoma were treated with intra-arterial yttrium-90 microspheres as part of a single-centre prospective study. Researchers administered 526 (average, 1.8) Y-90 treatments. Researchers reviewed 1,250 scans to assess response and time-to-progression (a surrogate marker that might imply — but does not prove — improved survival). Survival by stage was assessed. Overall time-to-progression was 7.9 months, said Salem. In other words, it took a median 7.9 months for the tumours to regrow after treatment. In oncologic standards for this disease, this is a very promising finding, said Salem. Survival times differed by the cancer staging system used: Child-Pugh A (17.2 months) and Child-Pugh B (7.7 months) and by Barcelona Clinic Liver Cancer staging (A, 26.9 months; B, 17.2 months).
Researchers used baseline age; sex; performance status; presence of portal hypertension; tumour distribution; levels of bilirubin, albumin and alpha-fetoprotein; and World Health Organisation/European Association for the Study of the Liver response rates to predict survival. Toxicities included fatigue (57%), transient pain (23%), nausea/vomiting (20%) and exhibited grade 3/4 bilirubin toxicity (5%).
