Real-world outcomes of selective internal radiation therapy with 90Y resin microspheres in HCC/mCRC: RESIN registry Asia

Asia-Pacific guidelines recommend selective internal radiation therapy (SIRT) as an alternative to transarterial chemoembolization for patients with intermediate or advanced hepatocellular carcinoma (HCC) and, in more limited circumstances, for metastatic colorectal cancer (mCRC). This multicenter, single-arm, prospective, observational registry evaluated safety and efficacy of SIRT with 90Y resin microspheres for HCC or mCRC in Asia. Adults (n = 202) with HCC or mCRC eligible for, and scheduled to receive, SIRT with 90Y resin microspheres at participating centers were recruited. Dosimetry methods used were body surface area or partition model at the physician’s discretion. The primary endpoints were overall response rate (ORR), frequency of treatment-emergent adverse events (TEAEs) and serious adverse events (SAEs), and liver function baseline changes. ORR at 3 or 6 months was 56% (HCC) and 33% (mCRC). 491 TEAEs were reported in 125 patients and 71 SAEs were reported in 29 patients. Performance status was maintained or improved in most patients 6 months after SIRT. SIRT may offer clinicians a targeted, single-use approach for HCC or mCRC palliative care or for tumor down-sizing or down-staging in Asia. Controlled trials of SIRT using personalized dosimetry could further define a role for SIRT in these populations. Selective internal radiation therapy (SIRT) is a treatment for patients with liver cancer – including primary tumors (those that start in the liver) and metastatic tumors (when the cancer has spread to the liver from elsewhere in the body). This study involved 202 adult patients from Singapore, Taiwan and Thailand who were able to receive SIRT. The main goals were to measure the benefits of SIRT and to check for side effects. These effects were studied in everyday medical practice. The results showed that 56% of patients with primary liver cancer and 33% of patients with metastatic tumors had a response to SIRT within 6 months of treatment. Patients with primary liver cancer survived for a median of 23.4 months. Patients with metastatic tumors survived for a median of 13.6 months. These results are similar or better to earlier studies of SIRT. About 1 in 10 patients went on to have surgery to remove their tumors or had liver transplantation. In most patients, the ability to function normally and care for themselves stayed the same or improved after SIRT. As expected with this type of treatment, side effects were common, and 29 patients had serious side effects. Side effects were similar to those seen previously with SIRT. This study suggests that SIRT is a useful addition to liver cancer treatments in Asia. This observational registry of selective internal radiation therapy (SIRT) with 90Y resin microspheres in Asia showed an overall response rate of 56% and 33% in patients with HCC and mCRC, respectively. SIRT may offer another targeted therapy for HCC and mCRC management in Asia.