Take Home:

1- PSA doubling time and the proximal PSA value are excellent predictors of the timing to the formation of metastatic prostate cancer in men who experience a biochemical recurrence (PSA only after surgery).

2- As the PSA doubling time decreased (became shorter) the risk increases for the development of metastatic disease.

3- A proximal PSA greater than or equal to 10ng/ml further increased the risk of developing metastatic prostate cancer.

Dr. Markowski and colleagues from Johns Hopkins University presented a study at the recent ASCO meeting that assessed the implications of PSA doubling time (PSADT) and proximal PSA scores (defined as the most recent value >6 months prior to developing a metastasis) for predicting metastasis free survival (MFS) among men with biochemical recurrence after a radical prostatectomy (RP).

Their objective was to identify men with PSADT that was <12 months and identify a PSA cut-point (proximal PSA) that predicts an increase in the risk of developing metastasis (M+).

The PIs combined data taken from two institutions, the Center for Prostate Disease Research and the Johns Hopkins databases. Their cohort included 31,296 men of which 513 men had a biochemical recurrence (BCR) (a PSA only recurrence) having a PSA of >0.2ng/ml with PSADT <12 months who did not receive any adjuvant or salvage hormone therapy or radiation treatment.

These 513 men were prospectively followed until they had demonstrated radiological evidence of developing a metastasis (M+). All the subject men were evaluated yearly with more than 1 PSA test as well as scans at regular intervals until they became M+.

Among the 513 men included in the analysis M+ occurred in 218 men over a median follow-up of 9 years. They found that the risk of developing M+ disease increased successively for men with PSADT 6.0-7.5, 4.5-6, 3.0-4.5, and <3.0 months, adjusted for the man’s stage and Gleason score.

Findings

Proximal PSA ≥10ng/ml significantly increased the risk of developing M+ disease in men with PSADT <12 mos, regardless of PSADT subgroup (HR 2.95, p<.0001).

Median MFS was 4.0 years at proximal PSA >10ng/ml vs 20 years at proximal PSA <10ng/ml.

The authors concluded that in men with PSADT<12 months, PSADT subgroups <7.5 months and proximal PSA >10ng/ml are independent predictors of MFS. Furthermore, a proximal PSA ≥10ng/ml further define the risk of M+ in biochemical recurrence of prostate cancer with PSADT<12 months. With additional validation, this information may provide utility in counseling men as they develop a BCR.

This study is particularly important because of its long-term follow-up and the large number of subjects gathered from two different cohorts.

At the 2017 ASCO Annual Meeting - June 2 - 6, 2017 - Chicago, Illinois, USA Presented by: Mark C. Markowski, MD, Ph.D., The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins University, Baltimore, MD, USA

Co-Authors: Daniel Suzman, Yongmei Chen, Bruce J. Trock, Jennifer Cullen, Zhaoyong Feng, Emmanuel S. Antonarakis, Channing Judith Paller, Misop Han, Alan W. Partin, Mario A. Eisenberger

Joel T. Nowak, MA, MSW wrote this Post. Joel is the CEO/Executive Director of Cancer ABCs. He is a Cancer Thriver diagnosed with 5 primary cancers - Thyroid, Metastatic Prostate, Renal, Melanoma and a rare cancer, Appendiceal Cancer.