The Clínica Universidad de Navarra (CUN), Pamplona, Spain, recently celebrated its tenth anniversary of using Yttrium-90 (Y-90) microsphere radioembolization for the treatment of liver cancer. CUN was a European pioneer in the use of radioembolization, or selective internal radiation therapy (SIRT) with SIR-Spheres microspheres and has treated over 400 patients using the procedure.
“From the 400 treated patients, there are very clear data on the efficacy of radioembolization. This technique has in many instances enabled rescue surgery in patients for whom surgery was not initially indicated”, Bruno Sangro, director of the CUN’s Liver Unit explained. “Over this past decade, we have improved the way we select patients and perform the treatment, and this has enabled us to reduce the side-effects.”
Treatment with resin Yttrium-90 microspheres, a procedure developed by Sirtex, has now become widespread for patients with liver cancer. Although disease control is achieved in a high number of patients, the duration of this effect is very variable. However, it is noteworthy that of the first two patients treated at the Hospital ten years ago, one is living with controlled disease and the other is disease free thanks to a transplant which was initially contraindicated, a press release from Sirtex states.
Sangro describes treatment with Yttrium microspheres as a complex, multidisciplinary procedure that requires the close collaboration of several departments such as nuclear medicine, radiology, and interventional Radiology, hepatology, oncology and others. In hepatocellular carcinoma (155 of the 400 patients treated at CUN had this type of tumour), the results show that“the treatment was effective in preventing the growth of treated lesions: it achieved disease control in over 80% of patients, sometimes over prolonged periods of time, and in some very selected patients eradication was even achieved”. However, radioembolization does not prevent the possibility of new lesions occurring in the liver or other organs.
Sangro emphasised that “radioembolization is a good palliative treatment, and can be added to other options already available at the Clínica Universidad de Navarra for primary tumours. Furthermore, it can open the door to other curative treatments, such as liver transplantation, liver resection or percutaneous ablation. It could also enable the complete elimination of the tumour.”
The results obtained by the CUN´s multidisciplinary team can be analysed according to tumour type, although in all cases the patients treated had a poor prognosis and advanced disease. Three years after treatment, 18% of patients with hepatocellular carcinoma and 16% of those who had hepatic metastases from colorectal cancer were alive. In the absence of treatment with Y-90 microspheres the expected three-year survival rate is between 1% and 5% of patients.
Results in patients with liver metastases
For patients with neuroendocrine hepatic metastases, the three-year survival rate is 64%, which is not significantly different compared to the survival rate without treatment with microspheres (40–50%). However, the main benefit to these patients lies in improving quality of life by controlling the symptoms.
Patients with hepatic metastases from gastrointestinal and breast cancer have also been treated with this procedure at CUN. The technique is used in certain patients with colon cancer: “either those who have already received all the possible treatment options, used alone or concomitantly with systemic treatments, or as a means of consolidating the response obtained with initial chemotherapy, thus prolonging its effect. Local control of the disease is relatively good because most of the relapses are produced outside the liver”, said Javier Rodríguez, of the CUN Oncology Department.
“It has been demonstrated that these spheres curb and reduce the disease in colon tumours with liver metastases that have relapsed after other systemic treatments. There are studies comparing a group receiving a combination of chemotherapy and spheres with another group of patients who only receive chemotherapy. The group who received the combined therapy demonstrated, at medium-term, a significantly superior probability of decreasing the metastatic disease and of a higher survival time”, explains Rodríguez. In patients with breast and kidney tumours, it has been observed that after a follow up of more than two years “prolonged control of the disease has been achieved”
In other types of treated tumours, control of the disease ranges from six to 12 months. Rodríguez considers that “data on gastrointestinal tumours support the effectiveness of the technique as third or fourth-line treatment, which indicates its potential benefit in patients who have had less pre-treatment”. In fact, CUN has participated in international studies to support the use of first-line radioembolization in persons for whom surgery is not an option. For this reason, the CUN specialist estimates that in the future this technique can be brought forward to the initial stages, taking advantage of a good prior assessment and combining it with other procedures.
According to Sangro, “Radioembolization can be administered in combination with chemotherapy in those tumours that are sensitive to this treatment. Furthermore, it is well tolerated, does not require long stays in hospital, (patients usually remain in hospital just one day, or may even not be hospitalised) and it has a low risk of complications.”