Interventional medicine refers to an emerging discipline that diagnoses and treats diseased tissues or organs through special guidewires, catheters, and puncture needles under the guidance of medical imaging equipment such as DSA, CT, MRI, and ultrasound. It is an indispensable and important component of malignant tumors diagnosis and treatment.
Tumor interventional therapy can be divided into vascular interventional therapy and non-vascular interventional therapy, featuring minimal invasion, precision, efficiency, safe, good reproducibility, and few side effects. Recently, Dr. Zhong Xiaojun from the Interventional Department deliver lecture about interventional therapy’s ‘three weapons’.
"Infusion" - killing tumors by local high-concentration chemotherapy drugs
"Infusion" means that under the guidance of imaging equipment, doctors send catheters from outside the patient's body into the arteries that feed the tumor, and infuse high-concentration therapeutic drugs directly into the tumor lesions, which can kill tumor cells or inhibit their growth and reduces the toxic effects of chemotherapy drugs on normal tissue cells. Currently, it has been applied to malignant solid tumors derived from various tissues throughout the body, including malignant tumors of the head and neck, malignant tumors of the chest and abdomen, malignant tumors of bone and soft tissue, and various metastatic tumors throughout the body.
Transcatheter arterial infusion chemotherapy (TAI) is a type of intra-vascular drug infusion. Arterial infusion of drugs can reduce the binding of drugs to plasma proteins. Studies have proven that direct infusion of drugs into target organs through arteries can increase drug concentration by 4-22 times and increase efficacy by 4-10 times, while super-selective intubation can increase drug concentration by 25 times. Due to the first-pass effect, TAI route can significantly improve the efficacy and reduce systemic toxic and side effects. Besides, some drugs have been confined due to serious side effects when administered systemically. However, they can be used safely when administered through the artery.
Drug-given methods:
(1) One-time shock infusion
That is, injecting drugs into the target artery within a short period of time (usually 30 minutes to several hours), and then withdrawing the tube to end the treatment. This method features rapid and simple operation, few complications and simple care. However, the short contact time between the drug and the lesion and the inability to re-administer the drug may affect the efficacy.
(2) Arterial block chemotherapy
The purpose of this method is to reduce the blood flow around the target lesion before performing infusion chemotherapy, further increase the drug concentration in the lesion area and prolong the stagnation time. This method includes balloon catheter perfusion, arterial pressurization chemotherapy perfusion and degradable starch microorganisms. spheres and biodegradable albumin microsphere blocking method.
(3) Long-term drug infusion
Compared with one-time shock infusion, long-term drug infusion last longer. The infusion can be divided into continuous or intermittent, and suitable for palliative treatment. Including Hepatic Artery Infusion Chemotherapy (HAIC) and fully implantable catheter cartridge system.
"Block" - cuts off "supply" and "starves" tumors to death
"Block", or embolization, refers to inserting a catheter into the nutrient artery of the tumor and then injecting embolizing agent (lipiodol, gelatin sponge, etc.) through the catheter to embolize the artery and cut off the source of nutrients for tumor growth. Its main principle is to block target blood vessels to cause ischemic necrosis; block or destroy abnormal vascular beds, lacunae and channels to restore hemodynamics to normal; block blood vessels to reduce distal pressure or block ruptured blood vessels in diameter, which is beneficial to stop bleeding when the tumor ruptures and bleeds.
This therapy is most commonly used in tumors with rich blood supply and malignant solid tumors such as liver cancer and lung cancer. Especially for tumors that cannot be surgically removed, vascular embolization therapy can control the tumor to a certain extent and sometimes shrink the tumor to operable stage. It is also used for stopping bleeding caused by tumor invasion or rupture, such as cervical cancer, nasopharyngeal cancer, liver cancer, bladder cancer, etc. In addition, for a small number of benign tumors with rich blood supply, such as uterine fibroids, adenomyosis, hepatic hemangioma, etc., the tumors can be completely disappeared, significantly reduced, and has relatively long stable period through embolization.
"Open" - relieves obstruction
"Open" means opening up stenosis, occlusion, obstruction, dissolving or removing thrombus, etc. Precise puncture under the guidance of CT or Ultrasound, through thrombolysis, thrombectomy, balloon dilation, and stent Implantation and other methods to complete the recanalization of occlusion, removal of thrombus or emboli, or recanalization through thrombolysis. Other natural orifices, such as the esophagus, intestine, biliary tract, etc., can be recanalized through balloon dilation or stent implantation.
It is suitable for treating deep vein thrombosis in the lower extremities (filter placement + thrombolysis/thrombolysis + stent implantation), arterial stenosis in major parts (renal artery stenosis, subclavian artery stenosis, carotid artery stenosis, vertebral artery stenosis, lower extremity artery stenosis, etc. Dilation and stent implantation), chronic arterial occlusion + acute thrombosis (emergency thrombolysis, thrombectomy, dilatation and stent implantation, stent implantation, etc.), hollow organ stenosis or obstruction (esophageal stent, intestinal stent, bile duct stent implantation ) and other diseases.
In recent years, interventional treatment of malignant tumors has made great progress in both basic and clinical research. The continuous emergence of various new materials, new equipment and technologies has injected lasting and vigorous vitality into the interventional treatment. However, some interventional diagnosis and treatment technologies still require high-quality evidence-based medical evidence to verify their efficacy.
On the other hand, the treatment of malignant tumors increasingly emphasizes multidisciplinary comprehensive treatment, such as TACE combined with ablation or radiotherapy and chemotherapy, the combined use of different ablation techniques, ablation combined with radiotherapy and chemotherapy, and the combination of interventional therapy and target immune drugs. It is worth noting Interventional therapy is not an all-in-one treatment suitable for all tumor types and all stages. A suitable individualized comprehensive treatment plan should be selected according to the stage of the tumor and standard treatment guidelines.