Outcomes in patients with Gleason score 8-10 prostate cancer: relation to preoperative PSA level

Study Type – Therapy (case series) Level of Evidence 4 What's known on the subject? and What does the study add? High‐grade prostate cancers are associated with poor disease‐specific outcomes. A proportion of these tumours produce little PSA. This study demonstrates that among Gleason 8–10 prostate cancers, some of the worst survival outcomes are associated with the lowest PSA levels.

OBJECTIVE

• ? To assess outcomes of patients with Gleason score 8–10 prostate cancer (CaP) with a low (≤2.5 ng/mL) vs higher preoperative serum PSA levels.

PATIENTS AND METHODS

• ? From 1983 to 2003, 5544 patients underwent open radical prostatectomy, of whom 354 had a Gleason 8–10 tumour in the prostatectomy specimen.
• ? Patients were stratified according to preoperative PSA level into four strata: ≤2.5 ng/mL (n= 31), 2.6–4 ng/mL (n= 31), 4.1–10 ng/mL (n= 174), and >10 ng/mL (n= 118).
• ? We compared biochemical progression‐free survival (PFS), metastasis‐free survival (MFS), and cancer‐specific survival (CSS) as a function of preoperative PSA level.

RESULTS

• ? Patients with PSA level ≤2.5 ng/mL were more likely to have seminal vesicle invasion (P= 0.003).
• ? On Kaplan–Meier survival analysis, patients with a PSA level ≤2.5 ng/mL had proportionately worse outcomes than their counterparts with higher PSA levels.
• ? The 7‐year PFS in the PSA ≤2.5 ng/mL stratum was lower than those of the PSA 2.6–4 ng/mL and 4–10 ng/mL strata (36% vs 50 and 42%, respectively); however, the lowest 7‐year PFS was found in those with a PSA level >10 ng/mL (32%, P= 0.02).
• ? Gleason score 8–10 tumours with a PSA level ≤2.5 ng/mL also tended to have the lowest 7‐year MFS (75, 93, 89 and 92% for PSA level ≤2.5, 2.6–4, 4.1–10 and >10 ng/mL, respectively, P= 0.2) and CSS (81, 100, 94 and 90% for PSA level ≤2.5, 2.6–4, 4.1–10 and >10 ng/mL, respectively, P= 0.3), although these differences were not statistically significant.
• ? In the subset with palpable disease, Gleason grade 8–10 disease with PSA level ≤2.5 ng/mL also was associated with a worse prognosis.

CONCLUSIONS

• ? In patients with Gleason grade 8–10 disease, a proportion of these tumours are so poorly differentiated that they produce relatively little PSA.
• ? Patients with high‐grade, low‐PSA tumours had less favourable outcomes than many of those with higher PSA levels.