Impact of time to metastatic disease onset and extent of disease volume across metastatic hormone-sensitive and castration-resistant prostate cancer

Abstract

Objective

In recently published phase III trials, overall survival (OS) differences were demonstrated in patients with secondary vs. De Novo and low vs. high volume metastatic hormone-sensitive prostate cancer (mHSPC). We hypothesized that these factors may also be attributable in real-world setting of new intensified combination therapies and in metastatic castration resistant prostate cancer (mCRPC) patients.

Materials and methods

We relied on an institutional tertiary-care database to identify mHSPC and subsequent mCRPC patients. The main outcome consisted of time to mCRPC and OS. Patients were stratified according to De Novo vs. secondary and low vs. high volume mHSPC and mCRPC, respectively.

Results

Of 504 mHSPC patients, 371 (73.6%) were De Novo vs. 133 (26.4%) secondary mHSPC. Patients with De Novo and high volume mHSPC harbored shorter time to mCRPC and OS than secondary and low volume mHSPC patients (both P < 0.01). After stratification regarding disease volume, median time to mCRPC differed significantly between De Novo high volume (DNHV) vs. De Novo low volume (DNLV) vs. secondary high volume (SecHV) vs. secondary low volume mHSPC patients (SecLV, P < 0.001). Similarly in OS analyses, median OS was 44 vs. 53 vs. 88 vs. 120 months for respectively DNHV vs. SecHV vs. SecLV vs. DNLV mHSPC (P < 0.001). After progression to mCRPC, the effect of onset of metastatic disease and metastatic volume was still observed (all P < 0.01).

Conclusion

Patients with DNHV mHSPC harbor worse prognosis in a real world setting and in the light of combination therapies. This effect is also discernible in the context of mCRPC.