A new study just published in BJU International offers data suggesting the idea that all men found to have positive seminal vesicles (SV+) after radical prostatectomy should receive immediate adjuvant treatment with external beam radiation and androgen deprivation therapy (ADT).
We should point out immediately that this is a retrospective analysis rather than a prospective clinical trial.
Bastide et al. assessed their records on 4,090 men, all given a radical prostatectomy between 1994 and 2008 at nine centers in France. From these 4,090 men, they were able to identify 199 patients who met all of four specific criteria:
- A pathologic finding of positive seminal vesicles after radical prostatectomy
- An effectively undetectable PSA level post-surgery
- No evidence of lymph node metastasis at the time of surgery
- Patient follow-up data for a minimum of 18 months
Analysis of the available data from these 199 patients provided the following information:
- Patients could be categorized into four treatment groups post-surgery.
- 82/199 men (41.2 percent) received no further treatment (Group A).
- 41/199 men (20.6 percent) received adjuvant radiation therapy only (Group B).
- 26/199 men (13.1 percent) received adjuvant ADT only (Group C).
- 50/199 men (25.1 percent) received adjuvant radiation therapy and adjuvant ADT (Group D).
- The average (mean) follow-up period was 60.3 months (range, 18 to 185 months).
- 88/199 patients (44.2 percent) had biochemical recurrence of their disease.
- The estimated probability for biochemical recurrence-free survival at 5 years was
- 32.6 percent for men in Group A
- 44.4 percent for men in Group B
- 48.4 percent for men in Group C
- 82.8 percent for men in Group D
- The estimated probability for biochemical recurrence-free survival at 7 years was
- 25.9 percent for men in Group A
- 28.6 percent for men in Group B
- 32.3 percent for men in Group C
- 62.1 percent for men in Group D
The authors conclude that: (a) radical prostatectomy alone is not a sufficient form of treatment for most men with positive seminal vesicles; (b) the combination of adjuvant radiation therapy with adjuvant ADT offers a substantial survival benefit compared to the other options commonly in use.
The ability to define exactly which men are at high risk for clinically significant, progressive disease at the time of diagnosis and immediately following first-line therapy is a major challenge in the management of prostate cancer. Based on the data provided above, the authors are effectively suggesting that all men found to have positive seminal vesicles at the time of surgery should be given immediate adjuvant radiation and ADT to optimize their probability of long-term survival. However, this recommendation is not based on actual survival data. We do not know how many of these men actually died of prostate cancer, how many went on to have evident metastatic disease, or how many lived out the remainder of their lives without evidence of clinically significant progression (as opposed to biochemical recurrence).
It is well understood that biochemical recurrence after first-line therapy is not necessarily a proxy for prostate cancer-specific mortality, nor is it a proxy for the occurrence of prostate cancer metastasis. The appropriateness of adjuvant radiation and adjuvant ADT in men found to have positive seminal vesicles at the time of surgery would appear to need to take some other factors into account, including the patient’s age/life expectancy, his comorbidity status, and his personal opinions about risk. On the other hand, what does seem to be clear from this study is that if it is determined that adjuvant therapy is appropriate for a man with positive seminal vesicles at the time of surgery, then the combination of radiation therapy and androgen deprivation would seem to be more appropriate than either radiation therapy or ADT alone.