Interventional Radiology Treatments for Kidney Cancer
Kidney cancer is the eighth most common cancer in men and the tenth most common cancer in women. The most common type of kidney cancer is renal cell carcinoma, which occurs in the parts of the kidneys called renal tubules that filter blood and produce urine. About 85 percent of kidney tumors are renal cell carcinomas. When kidney cancer spreads outside the organ, it can spread to the other kidney, lymph nodes, lungs, bones, or liver.
The gold standard treatment is laparoscopic partial nephrectomy surgery. However, some patients may be treated with kidney-sparing treatment in cases of high risk for surgery, such as underlying diseases, multiple recurrent tumors, borderline renal function, or having a solitary kidney. The most important kidney-sparing methods are minimally invasive methods performed by interventional radiology.
In addition, given the success of the freezing method (percutaneous cryoablation) performed by interventional radiology, the patient may prefer this method himself. He may not want to undergo surgery. Urologists and interventional radiologists should work together to decide whether the less invasive method of freezing or burning (percutaneous ablation) can be performed safely and effectively.
Prevalence and Risk Factors
More than 32,000 Americans are diagnosed with kidney cancer each year, most of whom have no symptoms. In general, people with kidney cancer are over the age of 40. Kidney cancer occurs twice as often in men as in women.
Other risk factors include:
Smoking
Obesity
High blood pressure
Long-term dialysis
Von Hippel-Lindau syndrome
Symptoms
The incidence of kidney cancer is increasing. Modern imaging technology makes it easier to detect small, asymptomatic tumors that are normally difficult to detect.
Small tumors often do not cause symptoms. Many are discovered on standard imaging studies, such as CT scans, MRIs, or ultrasounds, which are performed on patients who come to the emergency room for other reasons. These small tumors are the best candidates for nonsurgical treatment options. If the patient has symptoms, they may be:
Blood in urine
Persistent flank pain
A mass or lump near the abdomen
Weight loss
Fire
Feeling very tired
Kidney Cancer Diagnosis
In addition to a basic health exam, urine test, and blood tests, several other techniques may be used to diagnose kidney cancer. A CT scan, MRI, or ultrasound may be done to see inside the body and identify tumors.
An imaging-guided needle biopsy should be performed, tissue samples should be taken and examined under a microscope by pathologists.
Pathologists and other specialists can determine what type of cancer it is and whether it is fast-growing or slow-growing. This information is important in deciding the best type of treatment. Open surgery is often performed to obtain tissue samples for biopsy. However, in many cases, tissue samples can be obtained without open surgery using interventional radiology techniques. When first diagnosed, 25 to 30 percent of patients have had the tumor spread to other tissues.
Needle biopsy
A needle biopsy, also called an image-guided biopsy, is usually performed using moving X-ray techniques (fluoroscopy), computed tomography, ultrasound, or magnetic resonance (MRI) to guide the procedure. In most cases, needle biopsies are performed with the help of equipment that creates computer-generated images, allowing radiologists to view areas inside the body from various angles. This “stereotactic” equipment helps them pinpoint the exact location of abnormal tissue.
Needle biopsy is typically an outpatient procedure with very few complications. Less than 1 percent of patients develop bleeding or infection.
Advantages of Needle Biopsy
With image guidance, samples can be taken without damaging blood vessels and vital organs.
Recovery times are generally shorter and patients can resume normal activities more quickly.
It is less painful and the patient recovers quicker than with an open surgical biopsy.
Scarring and deformity that may be caused by open surgery can be avoided.
Side effects and complications such as fever are less common.
Large Piece Needle Biopsy
In this technique, radiologists use a special needle that allows for a larger biopsy sample. This technique is also used to obtain tissue samples from other masses detected during a medical exam or by mammography or other imaging scans.
A similar technique called fine-needle aspiration can be used to withdraw cells from suspected cancer. It can also be used to take samples of fluids that have collected in the body.
Kidney Cancer Treatment
In treating cancer patients, interventional radiologists can treat cancer without affecting other parts of the body or delivering drugs to the entire body.
Cryoablation (Freezing Treatment)
It is nearly 100% effective for kidney tumors up to four centimeters. Larger tumors can also be successfully treated with cryoablation, depending on size and location. Incubated lesions appear as dead tissue without recurrence at one-year follow-up after this treatment.3
The treatment can easily be repeated if needed.
The treatment has an excellent safety profile, and most patients are sent home the same day or the next day. The most common complication is blood pooling around the kidney, which usually resolves on its own.
In cryoablation, a probe sends gas directly to the tumor through a small incision in the skin. In cryoablation, an extremely cold gas is used to freeze the tumor to death. This technique has been used for many years by urologists in the operating room, but in the last few years, the needles have been made small enough to be used by interventional radiologists through a small incision in the skin without the need for surgery. The “ice ball” created around the needle freezes and destroys the tumor cells.
Thermal Ablation Applications (Heat Treatment)
Patients with serious non-tumor disease, recurrent tumors, impaired renal function, and patients with a single kidney may benefit from minimally invasive kidney-sparing treatment because of the risk of surgery. For these patients, interventional radiologists can treat the tumor with this new, less invasive procedure using needles specifically designed to eliminate kidney cancer. There is no incision or stitching in this method. The procedure is performed through a small incision.
Radiofrequency Ablation
For inoperable kidney tumors, radiofrequency ablation (RFA) is another nonsurgical treatment that kills tumor cells with heat while preserving healthy kidney tissue. Radiofrequency energy can be delivered without affecting the patient’s overall health, and most people can resume their normal activities within a few days.
In this procedure, an interventional radiologist uses a small needle through the skin to reach the tumor, and radiofrequency energy is transferred from the needle tip to the tumor, where heat is applied to the tumor cells and they are killed.
Additional RFA Considerations
It is more effective when the kidney cancer is small in size (5cm or less).
It can be performed with sedation or general anesthesia.
It is well tolerated – most patients can resume their normal routine activities the next day and experience only mild fatigue for a few days.
Can be repeated if necessary.
It can be combined with other treatment options.
Activity
If the tumor is small, RFA can shrink and kill the tumor.
Because it is a local treatment that does not harm healthy tissue, the treatment can be repeated as often as necessary. It is a very safe procedure and has become more widely used over the past few years. RFA is FDA-approved for use in renal cell carcinoma.
Risks
RFA risks include localized bleeding and mild pain. The heat from the radiofrequency energy burns the tissue, reducing the risk of bleeding. Bleeding that requires intervention is extremely rare. Heating of the tumor can cause heating of adjacent structures, which can damage some healthy tissue. This can be prevented by carefully assessing the size and location of the tumor before the procedure. Tumors close to structures such as the bowel may require special procedures (fluid injection) to create safe distances.
Non-surgical Treatment Methods for Advanced Kidney Tumors
Arterial Embolization (Vessel Occlusion Method)
Advanced renal cell carcinoma tumors are usually slightly larger and attack nearby structures and blood vessels. They may even spread to the blood vessels in one of the heart chambers. Some patients with advanced tumors may not be able to undergo surgery. Arterial embolization is a valuable treatment option for such patients.
During embolization, an interventional radiologist inserts a small tube (catheter) into the groin artery and guides it into the renal artery, which supplies blood to the kidney and tumor. The doctor injects small solid particles or special liquid agents into the artery to block blood flow to the kidney. The blockage prevents other substances needed for the tumor to grow from receiving oxygen, causing them to shrink.
In some patients, arterial embolization can shrink the tumor and make it suitable for surgery. In others, arterial embolization eliminates tumor-related complaints and improves the patient’s quality of life.
Arterial embolization is also used to perform surgical resection of large tumors. It blocks blood flow to the tumor, reduces the risk of bleeding, and reduces the amount of blood transfusion during surgery. Similarly, arterial embolization helps to shrink larger tumors and make them suitable for other closed methods.
Biological Therapy and Immunotherapy
Biological therapy is a systemic treatment that uses substances injected into the bloodstream to reach and affect all cells in the body. Biological therapy uses the body’s natural ability to fight cancer, such as using the immune system. New developments in immunotherapy have significantly improved the survival of patients with inoperable renal cancer.
New Cancer Treatments on the Horizon
Interventional radiology is playing a role in the development of new techniques that could advance cancer treatment in the future, including the use of magnetic particles to attract cancer-killing agents to tumors and the delivery of genetic material to fight or prevent cancer, called gene therapy. These techniques are still in the research phase but offer new hope in the fight against cancer.
“Magnetic” Chemotherapy
Interventional radiologists are researching a new technique that uses magnets to attract chemotherapy drugs to tumors. Microscopic magnetic particles are added to cancer-killing drugs and infused into the blood vessels that feed the tumor through a catheter. A rare earth magnet is placed directly over the tumor site in the patient’s body. The magnet pulls the drug-carrying particles out of the blood vessel so they can lodge in the tumor. Although the technique is still in the experimental phase, the new research is promising. Doctors hope it will enhance the effects of chemotherapy while avoiding some of the drugs’ side effects, such as hair loss and nausea.
Pain Management
Pain control is one of the most important elements of cancer care. Pain not only affects patients’ quality of life and ability to function, it can also reduce tolerance for necessary cancer treatments.
In most cancer patients, pain is caused by the tumor spreading into nerves and other tissues. For example, patients with pancreatic or stomach cancer often experience pain from the tumor spreading into a network of blood vessels and nerves in the abdomen called the celiac plexus. To treat pain, interventional radiologists insert a catheter or needle into the affected area and apply alcohol or other agents that destroy the nerves that cause pain, thereby relieving the pain.
In a technique called transcatheter embolization, interventional radiologists inject fine particles the size of grains of sand into the blood vessel that supplies blood to the tumor through a catheter. The particles cause clotting, which feeds the tumor and reduces pain.
Controlling Bleeding
If cancer spreads to blood vessels, it can cause hemorrhage or bleeding. An interventional radiology technique called transcatheter embolization can be used to clot the affected blood vessels and stop the bleeding.
Treatment of Organ Obstruction and Infection
Cancers can block the normal flow of urine or bile. This causes these fluids to increase in the body. If left untreated, these conditions are not only painful, but can also lead to organ failure or infection. To drain the accumulated fluid, interventional radiologists can insert catheters using X-ray guidance to drain the fluid.