Projecting outcomes of second-line (salvage) cryotherapy
Posted May 12 2010 12:00am
One of the problems of first-line radiation therapy is how to treat patients with a rising PSA (biochemical relapse) after it becomes clear that the rise in PSA is not simply a “biochemical bounce” in the PSA.
Salvage radical prostatectomy is a feasible procedure, but it has long been recongnized as a difficult operation, requiring great surgical skill, and with a high risk for significant complications. As a consequence, many patients with a rising PSA after first-line radiation therapy have historically had only hormone therapy as a serious second-line option for treatment.
Recently, improvements in cryotherapy have led to the increased use of this technique as a real second-line option for the salvage of patients in biochemical relapse following first-line radiation therapy. It is also possible to use high-intensity focused ultrasound (HIFU) as a similar salvage option (although access to HIFU in North America is limited at this time).
Earlier this year, Levy et al. published data providing some guidance about how well salvage cryotherapy patients can be expected to do over 3 years, based on their initial PSA levels after second-line treatment. This guidance is based on data from 455 hormone-naïve patients in the Cryo On Line Data Registry, all of whom were treated with whole-gland salvage croablation (SCA) of the prostate and were followed over time for PSA-based biochemical progression-free survival (bPFS) using the Phoenix criteria.
Levy and his colleagues categorized patients into three groups:
Group A had an initial PSA level of < 0.6 ng/ml after SCA and included 280 patients.
Group B had an initial PSA level between 0.6 and 5 ng/ml after SCA, and included 118 patients.
Group C had an initial PSA level of > 5 ng/ml after SCA, and included 57 patients.
Follow-up of these patients over time showed that:
For patients in Group A
For patients in Group B
For patients in Group C
The authors conclude that curative therapy remains extremely challenging for patients who show clear signs of relapse after first-line radiotherapy, and that there is no clear definition of clinical success after cryotherapy when used in the salvage setting. However, an initial PSA level of <0.6 ng/ml after SCA does suggest a promising 3-year outcome in about two-thirds of patients with such an initial response. By contrast, more than half the patients with initial PSA levels of ≥ 0.6 ng/ml after SCA are at risk of short-term biochemical progression within 1 year.