New Method in Prostate Cancer Treatment: Nanoknife Treatment

Nanoknife is a treatment method in prostate cancer. Used for prostate cancer treatment and varies according to the degree of cancer

Prostate cancer is the most common tumor in men in the United States of America and the second most common after lung cancer in our country and can result in death if left untreated.

Treatment of prostate cancer varies according to its stage, grade and life expectancy of the patient.

Stage I patients with low cancer burden can be taken under active surveillance, while surgical treatment can be performed for patients who have not had a more advanced stage, moderate and high-grade metastasis.

Hormone therapy and, if necessary, chemotherapy is applied to patients with metastasis.

Radiation therapy (radiotherapy) is used as an alternative treatment for non-metastatic errors. In recent years, multiparametric prostate MRI has been used in the diagnosis of prostate cancer, and a piece can be taken from the suspected cancer area seen here by fusion biopsy method.

With fusion biopsy, the diagnosis of prostate cancer is made more easily than normal biopsy and is a guide in determining the treatment principle. Biopsy procedure is normally performed from the anus (rectum) and during this procedure, microorganisms in the anus pass into the prostate and a serious prostatitis picture is encountered.

For this reason, we reach the prostate from the area between the bags and the anus (perineal area) and focus the MRI images with ultrasound and take the fusion biopsy procedure from the suspect area, that is, from the main target. The biggest advantage of this method is that infection and sepsis are almost never seen.

Non-surgical treatment alternatives for prostate cancer (radiofrequency tumor ablation, microwave tumor ablation, cryoablation) have found a wide area of ​​use in the field of oncology in the last 10 years and have made great advances in cancer treatment.

Local ablative treatments are used as the primary treatment option alone and / or as a complementary surgical treatment, where surgical treatment is not an option. However, as with all treatment options, local ablative treatments that are still in use also have certain limitations.

Recently, the most exciting non-surgical local treatment is Irreversible electroporation -IRE, i.e. nano blade prostate cancer treatment.

It is a very new method applied in prostate cancer that has not spread less than 2 cm under general anesthesia. The most important advantage in this method is that there is no incident that will damage the normal tissue such as burning and freezing.

It inflates cancer cells by giving electrical stimulation only to the marked area and disrupts their structure and renders them dysfunctional.

If an electric field is created by applying low-energy direct current (LEDC) between two electric surfaces to cells with cell membrane permeability, the phenomenon of temporary or permanent permeability in the cell membranes is called electroporation. It happens in two ways

1. Reversible Electroporation / Temporary Electroporation enables the insertion of a number of substances (drugs, DNA / RNA chains) into the cell, and since the cell membranes and structures remain intact after the procedure, cell homeostasis is not disturbed, cells remain alive.
2. If LEDC / low energy direct current of sufficient magnitude and time is given to the cell between two electrical surfaces, destabilizing electric fields (potentials) that cause nanoscale disruption in the cell double lipid layer are formed.

Pores are formed in the membranes of the cells that remain in the electric field that is formed, causing permanent permeability. After this procedure, cells die due to loss of intracellular calcium and cell membrane sodium / potassium gradient (loss of homeostasis).

This process with permanent permeability is called “Irreversible Electroporation” or IRE today.

• Not sensitive to Heat Loss (Heat Sink). IRE is a non-thermal electric field dependent event. Therefore, it is not sensitive to heat losses (Heat sink: Radiofrequency, HIFU, Microwave ablation) or heat sources (Heat sources: Cryoablation) due to anatomical structures located in the target ablation area.
• Has Tissue Protection Feature. Since it does not have a thermal effect, some connective tissues such as thermally sensitive capsular membranes, vessels, bile ducts and neurovascular bundles located in the electric field regions created during the IRE procedure can protect neurological tissues. IRE is located close to the airways and large vessels in pancreatic cancers that cannot be surgically intervened and treated with known local ablative treatment methods, with vascular invasion, HCC and metastatic liver tumors adjacent to the vascular and biliary tract, centrally located kidney tumors, prostate cancers affecting the neurovascular bundle of the prostate. It becomes an important treatment option in central lung tumors.

In order to create irreversible electroporation, 2 to 6 needle-tipped electrode probes are used.

The number of electrode probes to be placed around the target tissue mass depends on the size and shape of the target area.

The electrical field is created between the 2 electrodes in bipolar current configurations.

Unlike other ablation methods, tissue ablation occurs inward rather than outward from the needles.

Variable parameters Voltage (1500 V / cm), Distance between electrodes (up to 2 cm), Number of pulses (pulse # 90), pulse width (70 microseconds)

The beats sent are synchronized on the R wave in ECG. The IRE system has its own synchronization device.

After the current application, a significant hypoechoic lesion is displayed in the desired location of the IRE lesion in ultrasound follow-up.

Electric field created by 2 pin electrode probes

Electric field created by 4-needle electrode probe

The pathology result of the patient whose perineal fusion biopsy is performed from the suspicious area as a result of multiparametric MRI is expected. If prostate cancer is diagnosed as a result of pathology, the disease is staged. The treatment plan is determined according to the staging, grade and age of the patient. If the patient’s tumor is 2 cm or less, moderate to low grade and no metastasis, the patient may be a candidate for nanoknife treatment. After discussing all treatment alternatives of prostate cancer with the patient, nanoknife therapy is recommended.

The procedure is performed under general anesthesia in the position of the perineal fusion biopsy procedure and takes approximately 45 minutes. The number of probes to be applied is determined according to the diameter of the cancer in the patient’s prostate. Usually 4 probes are used. After the images in MRI and ultrasound images are overlapped, probes are placed in the suspected cancer area and electrical stimulation is given with the electrical special device and the procedure is completed. After a day in the hospital, the patient is discharged and called for 3-month controls.

The most important and frightening complication of the surgical treatment of prostate cancer is urinary incontinence and erectile dysfunction. This situation may also occur with other local treatments. Nanoknife treatment, on the other hand, does not cause these complications because no burning-freezing procedure is performed.

In studies conducted, no cancer cells were found in prostate fusion biopsies performed one year later in 80-90% of the patients treated with nanoknife. In the remaining 10-20% of patients, cancer cells were found in biopsies, and most of them were re-treated with the Nanoknife method and eventually no cancer cells were found. Very few patients have gone to surgery.