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Prostate Cancer
Salvage Cryosurgery in Prostate Cancer
Aaron E Katz
Associate Professor of Clinical Urology, and Vice Chairman of Urology, Columbia University Medical Center
Abstract
Radiation is a common form of therapy for newly diagnosed and localised prostate cancer patients. It is estimated that nearly one-third
of newly diagnosed prostate cancer patients will chose one form of radiation therapy as their primary treatment. Despite modifications
of delivering radiation to the gland, such as intensity modulation, 3D conformal and computer-assisted seed implantation, a number of
these patients will have a rise in the serum prostate-specific antigen (PSA) value in the years after radiation. Urologists will be required
to manage patients with rising PSA values and radiation-recurrent cancer. If a local recurrence is detected early, salvage cryotherapy can
be initiated. Recent advances in the technology and the technique of salvage cryosurgery have enabled the eradication of these tumours,
with a decrease in morbidity.
Keywords
Prostate cancer, radiation-recurrent disease, salvage therapy
Disclosure: The author has no conflicts of interest to declare.
Received: 11 August 2008 Accepted: 17 November 2008
Correspondence: Aaron E Katz, Department of Urology, Columbia University, Herbert Irving Pavilion, 11th Floor, 161 Fort Washington Avenue, New York, NY 10032, US.
E: AEK4@columbia.edu
Radiation is a common therapy for patients with newly diagnosed and Scientific Background
localised prostate cancer. It has been estimated that nearly one-third of Clinically based cryosurgical procedures grounded in well-recognised
newly diagnosed prostate cancer patients will choose one form scientific principles support physician-managed destruction of
of radiation therapy as their primary treatment. Despite modifications of radiation-recurrent prostate tumours.
11–13
Performed with multiprobe
delivering radiation to the gland such as intensity modulation, 3D devices and advanced imaging techniques, cryosurgery has yielded
conformal and computer-assisted brachytherapy, a significant number predictable and effective results in primary-setting long-term
of these patients will have a rise in their serum prostate-specific antigen treatment of prostate adenocarcinoma.
14–16
Prostate geometry dictates
(PSA) value some time after radiation has been administered. Urologists cryoneedle/cryoprobe (CN/P) placement: CN/P are placed to support
are often called on to manage patients with rising PSA values and thermal homogeneity at approximately -40°C throughout the prostate.
radiation-recurrent cancer. Following template-assisted ultrasound (US)-guided placement of
CN/P, the physician directs freezing from anterior to posterior in the
According to the recent literature, the frequency of biochemical failure gland. This sequencing supports clear visualisation and control of
with external-beam radiotherapy ranges from 20 to 66%.
1–8
However, in the ablative process under transrectal US (TRUS). The main principle of
the past many investigators used different definitions of biochemical prostate cryosurgery is a thermal therapy that extracts heat (thermal
failure. In 1997, the American Society for Therapeutic Radiology and energy) from the targeted tissue, resulting in a series of destructive
Oncology (ASTRO) defined biochemical failure as three consecutive PSA effects. Tissue response from cold injury, which can range from
level rises separated by three- to four-month intervals (ASTRO panel inflammation to total destruction, depends on the severity of freezing.
consensus statement). More recently, the Phoenix consensus definition, The lesion created by freezing is characterised by coagulation necrosis
PSA nadir plus 2ng/ml or more, was introduced.
9
As rising PSA levels can in the central region with a surrounding, relatively thin, peripheral
occur with both local and metastatic disease, an elevation does not region in which cell death is apparent. Under US, the ice ball can be
necessarily imply that the patient has local recurrence. clearly seen as a large hypoechoic region. The outer edge of the ice,
which is the warmest part of the ice, can be monitored as it appears
In addition, a PSA-level elevation may be due to benign causes. These as a hyperechoic rim.
factors make it difficult to clearly define a locally salvageable population.
Only approximately one-third of patients with biochemical failure will Salvage Cryosurgery
have local recurrence.
10
If local recurrence is detected early, salvage Salvage cryosurgery for curative intent should be strongly considered in
therapy is feasible. Recent advances in both technology and the men who have failed radiation therapy. The most appropriate candidates
technique of salvage cryosurgery have led to the ability to eradicate have documented persistent organ-confined prostate cancer, a PSA
these tumours, with a reduction in morbidity. <10ng/ml and a negative metastatic evaluation.
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