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Duration Of Survival Of Patients Who Developed
Hormone Refractory Prostate Cancer (August 2004)
It would be easy to
conclude from a cursory consideration of data from many articles and
texts that the median survival for patients with “hormone refractory”
prostate cancer (HRPC) is between 12 and 18 months. A recent example to
be considered is the ASCO abstract report of the encouraging 18.9 month
median survival for “patients with hormone-refractory prostate cancer”
treated with Taxotere/Prednisone. It can be misleading to compare
results of studies of men with HRPC without having sufficient
information about the details of the PSA values of the men in the group
being compared from different trials. In this example of the Taxotere/Prednisone
study group the median PSA at entry into the chemotherapy programs for
the group was 114 ng/mL, and 90% had bone metastases. Hardly early in
the “HRPC” phase of their disease!
The article, “Survival
of Patients with Hormone Refractory Prostate Cancer in the Prostate
Specific Antigen Era” (J UROL, April 1004, by Michael Oefelein et al.
addresses the issue of duration of overall survival following the
onset of hormone refractoriness, defined as the first PSA value
above 0.3 ng/mL despite castrate levels of testosterone. The median PSA
at which hormone deprivation was initiated in their retrospective study
was 204 ng/mL, and the lowest starting PSA was 1.8 ng/mL. However, the
survival calculations were based on the date when a man’s PSA exceeded
0.3 ng/mL level, despite the reality that AD was initiated at very
different times for men in the course of their rising PSA values. The
study examined the records of 131 men, the majority identified in 1999
in the practices at the Cleveland - University Hospitals, Case Medical
School. The mean age at diagnosis was 72, the mean Gleason score 8, and
the mean duration of androgen deprivation (AD) therapy was 58 months. AD
was continued to death. The median overall survival for men studied in
this manner was 53 months. The survival was further reported by
segregating the duration of survival data into two groups, one for men
free of metastatic disease to bone at the onset of AD, and a second
composed of men having bone metastases when AD was initiated. The median
duration of overall survival for the first group was 68 months, and was
40 months for the second. The study identified 6 “variables adversely
associated with survival after a patient enters hormone refractory,
androgen independent phase”: higher [pre-AD treatment PSA] nadir, p =
0.0000001; advanced age, lower pretreatment testosterone, p = 0.002;
obstructive uropathy; tobacco history, and higher alkaline phosphatase,
p = 0.02.
Bottom Line:
The data describing the duration of overall survival for men with HRPC
measured from a defined point (>.3 ng/mL) marking the onset of “hormone
refractoriness” is useful for counseling patients and for evaluation of
clinical studies.«
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