THE "NEW" PROSTATE CANCER INFOLINK

A recent publication has correlated nadir post-cryoablation PSA levels (i.e., the lowest PSA level achieved by the patient after treatment) with long-term biochemical disease-free survival in a risk-stratified cohort of patients with prostate cancer treated with cryoablation.

Levy et al. have used the records of 2,427 patients from the Cryo On-Line Data Registry to assess long-term biochemical disease-free survival after first-line treated with cryoablation. Biochemical failure was defined as a PSA level of the nadir PSA + 2 ng/ml (the Phoenix criterion) and patients were followed for up to 60 months after cryoablation.

The results of their analysis are shown in the table below, with patients classified as having low, intermediate, or high risk according to the standard D’Amico criteria.

The results shown in the table appear to be relatively predictable, with low-risk patients doing very well for up to 60 months so long as their nadir PSA post-treatment drops to ≤ 0.5 ng/ml.

The authors draw the following three conclusions:

• The nadir PSA level after prostate cryoablation is prognostic for biochemical disease-free survival.
• The nadir PSA level by itself it can not be used as a definition of disease-free survival since it has not been correlated with disease-specific or metastasis-free survival.
• A nadir PSA level of ≥ 0.6 ng/ml correlated with a biochemical failure rate of at least 29.5 percent at 24 months, regardless of risk level; patients with a nadir  PSA level of 0.6 ng/ml therefore require close followup.

The “New” Prostate Cancer InfoLink commends the authors for providing this set of useful outcome data based on a very large data set, but also reminds patients that individual outcomes will vary, based on a wide range of factors, including the skill and experience of the cryotherapist.