PROSTATE
CANCER CRYOTHERAPY
Prostate Cancer Cryosurgery
Cryosurgery Process
for Prostate Cancer Treatment
Cryosurgery (also known as cryotherapy or cryoablation) for prostate cancer treatment is typically done when the prostate volume is 50 grams or less in size. If the prostate is larger than 50 grams, the urologist may elect to downsize the prostate prior to treatment. Three to six months prior to the prostate cryotherapy treatment, the patient may be placed on hormone therapy to block production of male hormones, therefore causing prostate to shrink. Following hormone therapy, the prostate typically will be smaller thus improving the success of the cryotherapy treatment to freeze the entire prostate.
During the minimally invasive cryotherapy procedure, multiple cryoablation needles are inserted into the prostate through the perineum (the area between the anus and scrotum). This is done with the patient under general or local anesthesia, with general anesthesia being less common choice. An ultrasound probe is inserted into the rectum to view the prostate and the entire freezing process during the cryosurgical treatment. Cryotherapy in Prostate Cancer
Patients
During cryosurgery for prostate cancer, the patient
is placed in the dorsal lithotomy position. This
position places the patient so that his legs are
opened and lifted to a 90-degree angle. The perineum
is placed over the edge of the operating table.
The dorsal lithotomy position gives the doctor
a clear view of the insertion for the ultra thin
cryoablation
needles. While the prostate cancer cryosurgery
patient is anesthetized the doctor uses ultrasound
to view and as a monitor to guide the insertion
of the 17g (1.47mm) cryoablation
needles through the perineum into precise
locations within the prostate gland. A warming
catheter is used to protect the urethra from freezing
since the urethra passes through the prostate
gland. MTS™ (Multi-point Thermal Sensor) and thermal
sensor needles keep monitor of the temperature
within and around the prostate to ensure that
the prostate is being frozen to temperatures less
than -40⁰ Celsius while the adjacent areas of
the rectum and other organs are not frozen. The
use of the MTS needles to monitor temperatures
of the entire prostate and surrounding tissues
dramatically lowers the chance of incontinence,
rectal fistulae or other side effects.
When the cryoablation
needles and temperature sensors are in place,
a freezing agent, argon gas, is circulated through
the cryoablation
needles to create temperatures of negative
40 degree Celsius or colder. Circulating the extremely
cold argon gas through the cryoablation needles
creates a lethally cold iceball that freezes the
prostate and the cancer cells in it. Once the
targeted area is frozen, the thawing is employed.
The thawing process ruptures and kills the cells
in the prostate gland. This is called the freeze-thaw
process. This process is repeated to ensure all
cancerous cells are destroyed and help stop future
prostate cancer recurrence.
Throughout the cryoablation procedure, temperature sensors are used to allow physicians to determine when target temperatures have been reached. The cancer tumor and its blood supply are destroyed and the dead tissue is re-absorbed or remains in the body as harmless scar tissue.
When the freeze-thaw process is finished, the warming catheter is removed and a urinary catheter is inserted in place to help with any temporary urinary incontinence. The urinary catheter is typically removed after two or three days; unless incontinence persists.
Cryosurgery results for prostate cancer
are similar to radical surgery and radiation.
Read more about cryosurgery
treatment success rates.
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