Influence of Tumor Characteristics and Time to Metastatic Disease on Oncological Outcomes in Metachronous Metastatic Prostate Cancer Patients

Introduction

Metachronous metastatic prostate cancer (mmPCa) patients harbor different characteristics and outcomes, relative to DeNovo metastatic PCa patients. Onset of metastatic disease might be influenced by primary PCa characteristics such as Gleason score (GS) or cancer stage, as well as overall survival (OS) by timing of metastatic onset.

Patients and Methods

We relied on an institutional tertiary-care database to identify mmPCa patients. Kaplan Meier and Cox Regression models tested for onset of metastases and OS, stratified according to GS, pathological stage and time to mmPCa.

Results

Of 341 mmPCa patients, 8% harbored GS6 versus 41% versus 51% GS7 and GS8-10. Median time to onset of metastatic disease was 79 versus 54 versus 41 months for GS6 versus GS7 versus GS8-10 (P = .01). Moreover, median time to onset of metastases was 64 versus 44 months for pT1-2 versus pT3-4 mmPCa patients undergoing radical prostatectomy (P = .027). In multivariable Cox regression models, higher GS and pT-stage was associated with earlier onset of metastases. Additionally, significant OS differences could be observed for time interval of < 24 versus 24-60 versus 60-120 versus ≥ 120 months between primary PCa diagnosis and onset of mmPCa. Specifically, median OS was 56 versus 69 versus 97 months versus not reached (P < .01) for these categories. In multivariable Cox regression, shorter time to metastatic onset was associated with shorter OS.

Conclusion

Timing of mmPCa is strongly influenced by grading and pT-stage in real-life setting. OS benefits can be observed with longer time interval between primary PCa diagnosis and onset of mmPCa.