Physiological basis of interventional treatment for liver metastases 1. Normally, the portal vein is involved in about 70% of the liver blood supply and the hepatic artery in about 30%. 2, dual blood supply to the liver, liver metastases are mainly supplied by the hepatic artery (sigurdson et al. found that hepatic A perfusion is significantly higher than portal V perfusion by FUDR radiolabeling before biopsy of liver metastases). 3. Some scholars believe that hepatic artery supply is the main source of blood, and portal vein supply is secondary. Recent studies have shown that the portal vein is not involved in the blood supply of hepatic metastases. 4, Lautt et al. observed that the liver has the ability to alter oxygen extraction from the portal vein when hepatic artery blood flow is reduced or occluded. 5. Selective or super-selective hepatic artery cannulation is the basis for interventional treatment of hepatic metastases. Why choose intervention for liver metastases 1.Rising tumor incidence and rising trend of liver metastases incidence. 2.Liver metastases are often combined with poor liver foundation such as chronic liver disease, liver injury, etc. 3.The efficacy of systemic chemotherapy for liver metastases is poor. It has been reported that the clinical efficacy of 5-FU combined with oxaliplatin and irinotecan in the treatment of rectal cancer liver metastases is only about 20%. 4.Some tumors such as ocular malignant black, carcinoid tumor and islet cell tumor only metastasize to the liver and systemic chemotherapy is not sensitive. 5.Multiple interventional treatment methods: infusion chemotherapy, embolization, portal vein chemotherapy, anhydrous alcohol, particle implantation, radiofrequency ablation, etc. 6.Interventional treatment is local infusion of high concentration chemotherapy drugs and embolization to reduce systemic toxic reactions caused by chemotherapy drugs. The difference between interventional perfusion chemotherapy and intravenous chemotherapy perfusion systemic chemotherapy local concentration high local concentration low first pass effect no embolization – ischemia/oxygenation no local retention time no embolization chemotherapy synergistic no small side effects large large dose small I. Interventional chemotherapy for liver metastases (HAI) hepatic artery interventional chemotherapy method is percutaneous arterial puncture cannulation to the tumor blood supply artery, which should be drug concentration time effect The administration of chemotherapy can increase the local drug concentration of the target tumor and prolong the contact time between the drug and the tumor. Studies have confirmed that the concentration of anticancer drugs injected into the tumor site through arterial cannula can reach the tumor tissue 10-30 times higher than the general peripheral intravenous drug or oral drug, thus improving the efficacy and significantly reducing the systemic toxic side effects. Chemotherapeutic drug selection The doses of commonly used antitumor drugs are: 5Fu1000-1500mg, DDP60-100mg, MMC10-20mg, ADM40-60, EADM40-80mg, VP-16200-500mg; VCR1-2mg, CBP300-500mg, BLM10-40mg. BCNU100-300mg, DTIC200-800mg, CTX500-800mg, HCPT20-40mg, JZ1.4-1.8, platinum oxalate 150mg-200mg. The selection of drug species and dosage should be based on the pathological nature of the tumor, sensitivity to the drug and the patient’s tolerance, with the combination chemotherapy as the mainstay. (1) Each chemotherapeutic drug alone should have certain efficacy; (2) The mechanisms of various chemotherapeutic drugs are complementary and the toxic effects are complementary and overlapping; (3) Each chemotherapeutic drug should reach the maximum tolerated amount according to the patient’s condition; (4) The chemotherapeutic drugs must be cleared rapidly by the liver (high first-pass clearance), and the liver drug concentration is 30-100 times higher than that of the body circulation, which is more effective at high doses. (2) Chemoembolization (HAE) of liver metastases Commonly used types of embolic agents: (1) Iodine oil: after iodine oil is injected into the artery, it can disappear in normal tissues in a few days, while it produces “oil embolism” in tumor tissues and stays for a long time, from several months to one year, so it can be mixed with anti-tumor drugs for guided chemotherapy and marked with isotopes for internal radiation therapy. (2) Gelatin sponge (2) Gelatin sponge: It is a kind of medium-acting embolic agent, which is mostly made into powder, granule or strip, and can embolize different direct arteries with central embolic effect. 7-21 days can be absorbed and can be repeatedly embolized. (3) microsphere embolization agent: refers to the diameter of 50-200um embolization particles, clinical most of the microspheres containing chemotherapeutic drugs, used to embolize blood vessels such embolization agent must be super-selected after intubation embolization, otherwise serious complications can occur. (4) spring ring: for permanent embolization, clinical commonly used tungsten wire ring, fluffy wire ring, etc., mainly used for arterial trunk embolization, the effect is not good alone, mostly used on the basis of iodine oil or gelatin sponge embolization. (5) anhydrous alcohol: It is a long-acting embolic agent, which is easy to cause damage to the endothelium of tiny vessels and denaturation of proteins in blood to form coagulation mixture embolism. In addition, TH gum, hyoscyamus powder, ophiopogon oil, porcelain powder, etc. are in clinical research trials. Takayasu et al. clinical study embolization and tumor necrosis efficacy observation Embolization agent main tumor necrosis rate (%) subfocal necrosis rate (%) super liquid iodized oil 00 super liquid iodized oil + ADM136 super liquid iodized oil + ADM + gelatin sponge 8353 Embolization precautions 1. selective and super selective cannulation should be performed before embolization, and the catheter should be inserted into the tumor blood supply branch as much as possible. 2.Arteriography should be performed before embolization to understand the tumor blood supply and the presence of arteriovenous fistula. 3.The method of embolization and the amount of embolic agent should be chosen according to the specific situation. 4.The embolization agent should be mixed with contrast agent to monitor the flow direction and speed and to judge the degree of embolization. 5.It is better to use a balloon catheter to prevent reflux when injecting anhydrous alcohol. 6.The patient should be closely observed during embolization and the embolic reaction should be dealt with in time. 7.After embolization, keep X-ray film for review and follow-up. Indications and contraindications 【Indications】 (1) Various kinds of vascular rich liver metastases. (2) Preoperative palliative treatment of liver metastases and primary lesions. (3) Postoperative or chemotherapy insensitive metastases (4) Rupture and bleeding of tumor. (5) Arteriovenous fistula of tumor. Contraindications】 (1) Those who cannot selectively target arterial cannulation. (2) The embolization may cause the failure of an important organ. (3) Severe cachexia. Case 1: Liver metastasis of lung adenocarcinoma after intervention Case 2: Liver metastasis of gastric cancer after intervention Interventional procedure Case 3: Liver metastasis of pancreatic cancer after interventional treatment Interventional treatment