Thermal ablation in the management of oligometastatic colorectal cancer.

PURPOSE: To review available evidence on thermal ablation of oligometastatic colorectal cancer. METHODS: Technical and cancer specific considerations for percutaneous image-guided thermal ablation of oligometastatic colorectal metastases in the liver and lung were reviewed. Ablation outcomes are compared to surgical and radiation therapy literature. RESULTS: The application of thermal ablation varies widely based on tumor burden, technical expertise, and local cancer triage algorithms. Ablation can be performed in combination or in lieu of other cancer treatments. For surgically non-resectable liver metastases, a randomized trial has demonstrated the superiority of thermal ablation combined with chemotherapy compared to systemic chemotherapy alone in term of progression-free survival and overall survival (OS), with 5-, and 8-year OS of 43.1% and 35.9% in the combined arm vs. 30.3% and 8.9% in the chemotherapy alone arm. As ablation techniques and technology improve, the role of percutaneous thermal ablation may expand even into surgically resectable disease. Many of the prognostic factors for better OS after local treatment of lung metastases are the same for surgery and thermal ablation, including size and number of metastases, disease-free interval, complete resection/ablation, negative carcinoembryonic antigen, neoadjuvant chemotherapy, and controlled extra-pulmonary metastases. When matched for these factors, thermal ablation for lung and liver metastases appears to provide equivalent overall survival as surgery, in the range of 50% at 5 years. Thermal ablation has limitations that should be respected to optimize patient outcomes and minimize complications including targets that are well-visualized by image guidance, measure <3cm in diameter, and be located at least 3mm distance from prominent vasculature or major bronchi. CONCLUSIONS: The routine incorporation of image-guided thermal ablation into the therapeutic armamentarium for the treatment of oligometastatic colorectal cancer can provide long survival and even cure.

A novel irinotecan-lipiodol nanoemulsion for intravascular administration: pharmacokinetics and biodistribution in the normal and tumor bearing rat liver.

Colorectal cancer is one of the most common cancers in the United States and treatment options are limited for patients who develop liver metastases. Several chemotherapeutic regimens have been used for transvascular liver-directed therapy in the treatment of colorectal liver metastases without clear evidence of superiority of one therapy over another. We describe the development of a novel nanoemulsion through combining irinotecan (IRI), a first line systemic agent used for the treatment of colon cancer, with lipiodol, an oily contrast medium derived from poppy seed oil, and evaluated its pharmacokinetic and biodistribution profile as a function of portal venous chemoembolization (PVCE) versus transarterial chemoembolization (TACE) delivery. The Tessari technique was used to create a stable emulsion (20 mg IRI mixed with 2 mL lipiodol) with resultant particle size ranging from 28.9 nm to 56.4 nm. Pharmacokinetic profile established through venous sampling in Buffalo rats demonstrate that the area under the curve (AUC0-∞) of IRI was significantly less after PVCE with IRI-lipiodol as compared to IRI alone (131 vs. 316 µg*min/mL, p-value = .023), suggesting significantly higher amounts of IRI retention in the liver with the IRI-lipiodol nanoemulsion via first-pass extraction. Subseqent biodistribution studies in tumor-bearing WAG/Rjj rats revealed more IRI present in the tumor following TACE versus PVCE (29.19 ± 12.33 µg/g versus 3.42 ± 1.62; p-value = .0033) or IV (29.19 ± 12.33 µg/g versus 1.05 ± 0.47; p-value = .0035). The IRI-lipiodol nanoemulsion demonstrated an acceptable hepatotoxicity profile in all routes of administration. In conclusion, the IRI-lipiodol nanoemulsion via TACE showed promise and warrants further investigation as an option for the treatment of metastatic colorectal cancer.

Oligometastatic Colorectal Cancer Management: A Survey of the Italian College of Interventional Radiology.

AIM: European Society for Medical Oncology (ESMO) and National Comprehensive Cancer Network guidelines (NCCN) have recently included interventional procedures among the standard treatments for the management of colorectal cancer (CRC) oligometastatic disease (OMD). This study overviews the practice of Interventional Radiology (IR) in Italian centers. METHODS: A practice focused questionnaire on locoregional treatments of CRC-OMD was submitted to all Italian IR centers to assess practice patterns. RESULTS: Thirty-three IR centers completed the questionnaire. The majority reported practice was established within a tumor board (97%), which included input from hepatobiliary surgery (94%). When considering the number of percutaneous ablation and liver-directed trans-arterial therapies performed for all tumor types, 33.5% and 13.4% were performed to specifically treat CRC-OMD. Lung ablations for CRC OMD were performed in 45.5% of centers. Regarding liver ablation, The most common technology was the microwave ablation (68.1%), which was typically performed under US guidance (78%) with conscious sedation used as the most common anaesthesia method (81%). While indication for percutaneous IR treatments was heterogeneous, 51% were performed in combination with chemotherapy in unresectable OMD. Despite new ESMO and NCCN guidelines, 59% of centers did not subjectively appreciate any change in the perception of IR treatments by other specialists; however, 63%of respondents believe that IR will have a more relevant role in the CRC-OMD management in the future. CONCLUSION: CRC-OMD treatment represents a relevant part of the everyday clinical practice of the IR Italian centers with promising future prospects. Heterogeneity persists in clinical indications, requiring more robust evidence to set indications and to diffuse clinical applications.