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Prostate Cancer
Treatment Outcomes and biochemical disease-free rates of 86 and 74% at one and two
years, respectively.
Biochemical Outcomes
Over the past decade several institutions have published their salvage In another recently published large series also employing an argon-based
cryosurgery results. Many of the published series from the early 1990s had system, Chin et al. performed cryosurgery on 118 patients with recurrent
significant numbers of complications.
26,27
Despite the inability to adequately disease after radiation therapy, including five who had received
control the ice formation and target the gland in this ‘early’ cryosurgery permanent interstitial implants. They reported negative biopsies in 94%
period, follow-up PSA values and biopsy data from these series indicate that of these patients; the seven who had persistent disease underwent a
the introduction of lethal ice could eradicate radioresistant, locally second ablation procedure. In this series, 97% of patients had PSA nadirs
aggressive cancer. The high morbidity presented in these reports could be <0.5ng/ml, and 34% remained below this level with a median follow-up
attributable to a number of factors. For one, the use of thermocouples was of 18.6 months (68% had PSA <4ng/ml, and 10 patients developed
not yet available. In addition, there was a period of time when the US Food metastatic disease).
32
As in the Pisters et al. study, pre-procedure PSA
and Drug Administration (FDA) banned the urethral warming device and, as levels >10ng/ml, Gleason score ≥8, and stage 3/4 disease predicted
a consequence of inadequate warming, urethral sloughing was prevalent, biochemical failure.
resulting in pain, urinary retention, and incontinence. Furthermore, early
studies were performed using a liquid-nitrogen-based system that limited The third-generation cryosurgery system is equipped with a maximum of
the ability to control the growth of the ice ball. This, coupled with improper 30 smaller 17-gauge needle-like probes. Using this device, Creswell et al.
cryoprobe placement, led to the development of rectal fistulas. reported a 67% biochemical failure-free rate as defined by PSA levels
<0.5ng/ml for 20 salvage cryosurgery patients.
33
Han et al. also
reported a 74% biochemical failure-free rate at one year with the
The use of pressurized argon gas, third-generation system.
34
multiple probes (a maximum of eight),
Complications
and thermosensors has produced Recent advances in technology have significantly reduced the
better results compared with liquid-
complication rates associated with salvage cryosurgery. In the past,
incontinence rates following salvage cryosurgery exceeded 70%,
26
but
nitrogen-based systems for locally current studies being performed by de la Taille, Ghafar, Chin, and Han
recurrent cancer.
report rates of less than 10%. Despite these improvements, incontinence
rates in the salvage setting are still higher than those following primary
cryosurgery. Rectourethral fistula was also reported to occur more
Second-generation cryosurgical equipment led to significant advances in frequently in salvage cases; however, recent studies report that this
the technology. The use of pressurized argon gas, multiple probes serious complication has been virtually eliminated (rate of 0–3%).
(a maximum of eight), and thermosensors has produced better results Although rectal fistula is currently rare, rectal pain has been reported.
compared with liquid-nitrogen-based systems for locally recurrent cancer.
Although there has been no established set of parameters to define In a series of 35 patients studied by de la Taille who underwent
success or failure after salvage cryosurgery, persistent disease diagnosed cryosurgery of the prostate with an argon-based system, 37% who had
by prostate biopsy and a PSA cut-off value of 0.1–0.5ng/ml are prior radiation therapy had pain compared with 12% of patients who
commonly used to define outcomes. underwent primary cryosurgery. In a later study, Donnelly et al. reported
that rectal pain occurred in 17% (eight of 46) of salvage patients.
35
The
Published series have demonstrated promising results for this treatment cause of the pain is unknown but may be related to an ischemic event
approach. Using two freeze–thaw cycles, Cespedes et al. achieved a that occurs near the anterior rectal wall. After radiation, there may be
biopsy-negative rate of 93% and a biochemical failure-free survival reduced blood supply to this area, and introducing lethal ice may elicit
rate of 66% in a series of 150 patients mainly treated using the further devascularization. de la Taille, Ghafar, and Han reported urethral
first-generation liquid-nitrogen-based system.
28
However, these results sloughing and obstruction in 5–10% of patients. Even with the current
came at the price of high complication rates. Patients with pre-operative technologies and techniques, impotence rates remain high at more
PSA levels >10ng/ml or Gleason scores ≥8 were most likely to experience than 80%.
disease recurrence. Bahn et al. reported seven-year salvage biochemical
failure-free rates of 59 and 69% using cut-off values of PSA <0.5 and Quality of Life
<1.0ng/ml, respectively, in 59 patients.
29
There are two series reporting quality of life data in patients undergoing
salvage cryosurgery with third-generation devices. Robinson et al.
De la Taille et al. reported a biochemical failure-free survival rate of 66% assessed quality of life using the European Organization for Research and
at 12 months in a series of 43 salvage patients, with low complication Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ)-C30
rates.
30
In their experience, a PSA nadir of >0.1ng/ml following treatment instrument and the Prostate Cancer Index in 46 patients at baseline and
predicted eventual recurrence. Ghafar et al. used an argon-based at 24 months following salvage cryosurgery.
36
Quality of life returned to
cryosurgery system to treat 38 patients with biochemical recurrence pre-operative levels by 24 months in all domains, with the exception
after radiation.
31
They reported PSA nadirs <0.1ng/ml in 81.5% of urinary and sexual functioning. At 24 months, 29% of patients
44 US ONCOLOGY
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