Interstitial High-Dose-Rate Brachytherapy of Liver Metastases in Oligometastatic Patients

Abstract

Local ablative treatments have emerged as a promising treatment strategy for patients with oligometastatic disease. Among others, interstitial brachytherapy (iBT) is an upcoming treatment option for unresectable liver metastases. We report the feasibility and oncologic outcome of iBT of oligometastatic liver metastases performed in patients with limited tumor burdens in a high-volume center. Patients undergoing iBT between August 2017and March 2019 were included. A retrospective analysis of patient outcomes and treatment complications was performed. Patients treated for metastatic colorectal carcinoma (CRC) were compared to other histologies. A total of 141 iBT procedures were performed in 106 patients (male:52; female:54) and 244 liver metastases. Overall, 51% (54/106) of patients had a diagnosis of metastatic CRC. The median follow-up was 9 months, and overall survival (OS) was 92.3% at 6 months and 76.3% at 12 months. Local-relapse-free survival (LRFS) was 88.4% at 6 months and 71.5% at 12 months, with a significant difference between patients with CRC (84.1% and 50.6%) versus other histologies (92.4% and 92.4%, p < 0.001). A sub-group analysis showed a significant advantage in patients with CRC receiving a minimal dose (D100) of 20 Gy to the planning target volume. Treatments of smaller total liver-tumor volumes (<18 ccm) resulted in better LRFS rates. iBT is a safe and effective treatment approach for oligometastatic liver disease. A higher treatment dose is needed for patients with CRC. Moreover, lower metastatic burdens may be favorable for LRFS. Prospective studies are needed to assess the role of iBT in the oligometastatic setting as an alternative to other local ablative treatment approaches in patients with liver metastases.

Interstitial Brachytherapy for Hepatocellular Carcinoma: Analysis of Prognostic Factors for Overall Survival and Progression-Free Survival and Application of a Risk Stratification Model

“…Local ablative treatment techniques have emerged as promising strategies for HCC. iBT has been shown to be a safe and effective treatment option for liver lesions in early-stage HCC [ 23 , 24 ]. Patients referred to iBT usually are present with larger lesions or those not suitable to surgical resection or other local treatments.…”

Interstitial brachytherapy combined with PARP inhibitors in the treatment of chemoresistant recurrent epithelial ovarian cancer: A case report

“…However, due to its toxicity and the development of platinum-based chemotherapeutic agents, whole abdominal radiation is soon no longer routinely used in the clinical management of ovarian cancer and only used for the treatment of isolated lesions ( 26 , 27 ). Interstitial brachytherapy, a form of radiotherapy, has achieved excellent success treating a variety of solid cancers ( 28 , 29 ). Because the recurrent lesion is solitary in our patient, interstitial brachytherapy can provide a greater dosage to control the tumor and achieve good therapeutic benefits of CR without having the negative side effects of traditional radiotherapy, which is essential for improving the patient’s PFS.…”

Review of brachytherapy clinical trials: a cross-sectional analysis of ClinicalTrials.gov

“…Further research is needed to compare the safety and efficacy of brachytherapy to local ablative EBRT and systemic therapies in patients with non-resectable HCC and intrahepatic cholangiocarcinoma [ 48 ]. Although SIRT remains a primary area of research for liver malignancy indications, evaluations of HDR brachytherapy have previously been reported to be an effective treatment of liver metastases with good local control and low toxicity [ 49 , 50 ]. Long-term follow-up studies of LDR (n = 64) and HDR (n = 75) [ 51 ] brachytherapy to treat liver malignancies concluded that brachytherapy is an effective treatment option for unresectable primary and metastatic tumors, with one year LDR local control rates of 44% and HDR local control rates of 48–94% based on tumor size.…”