The CAPRA-S score versus subtypes of minimal residual disease to predict biochemical failure after radical prostatectomy

Nigel P Murray; Socrates Aedo; Cynthia Fuentealba; Eduardo Reyes; Anibal Salazar; Eghon Guzman; Shenda Orrego

doi:10.3332/ecancer.2020.1063

The CAPRA-S score versus subtypes of minimal residual disease to predict biochemical failure after radical prostatectomy

Ecancermedicalscience. 2020 Jun 25:14:1063. doi: 10.3332/ecancer.2020.1063. eCollection 2020.

Authors

Nigel P Murray^{1

2}, Socrates Aedo¹, Cynthia Fuentealba^{3

4}, Eduardo Reyes^{3

5

6}, Anibal Salazar^{7

8}, Eghon Guzman^{9

10}, Shenda Orrego^{9

11}

Affiliations

¹ Faculty of Medicine, University Finis Terrae, Providencia, Santiago 7501015, Chile.
² https://orcid.org/0000-0001-8154-8550.
³ Urology Service, Hospital DIPRECA, Las Condes, Santiago 7770199, Chile.
⁴ https://orcid.org/0000-0003-4100-6997.
⁵ Faculty of Medicine, University Diego Portales, Santiago 7770199, Chile.
⁶ https://orcid.org/0000-0001-8430-3030.
⁷ Department of Urology, Hospital de Carabineros de Chile, Ñuñoa, Santiago 8370179, Chile.
⁸ https://orcid.org/0000-0001-9319-4219.
⁹ Faculty of Medicine, University Mayor, Providencia, Santiago 7601003, Chile.
¹⁰ https://orcid.org/0000-0001-5012-6945.
¹¹ https://orcid.org/0000-0003-2860-2954.

Abstract

Objective: The objective of this study was to compare the CAPRA-S score (based on clinicopathological findings) and the subtypes of minimal residual disease (MRD) (based on the biological properties of cancer cells) to predict biochemical failure (BF) after prostatectomy radical.

Patients and methods: This was a prospective single-centre study of men who underwent radical prostatectomy. One month after surgery, the blood and bone marrow were taken for circulating prostate cell (CPC) and micrometastasis detection, identified using anti-PSA immunocytochemistry and defined as positive or negative. Patients were classified as Group A: CPC and micrometastasis negative, Group B: micrometastasis positive and CPC negative and Group C: CPC positive. CAPRA-S scores were classified as low, intermediate and high risk. Kaplan-Meier curves for biochemical failure-free survival (BFFS) and restricted mean survival time (RMST) to biochemical failure were determined and compared for up to 10 years.

Results: 347 men participated with a median follow-up of 7 years, BFFS decreased proportionally with increasing CAPRA-S score and HR 1.13 and 1.65 for intermediate and high risk, respectively. After 10 years, the BFFS and RMST were 68%, 47% and 16% and 9, 7 and 6 years, respectively. The BFFS curves for MRD were not proportional; Group A and B BFFSs were similar up to 5 years, and then, there was an increasing failure in Group B patients After 10 years, the BFFS and RMST were 95%, 57% and 27% and 10, 9 and 6 years respectively. The CAPRA-S score failed to distinguish between Groups A and B, and one-third of high-risk Group C had low-risk CAPRA-S scores. MRD hazard ratios were Group B 1.76 and Group C 4.03.

Conclusions: The MRD prognostic classification was superior to the CAPRA-S score in predicting BFFS and differentiated between early and late BF. The results need to be confirmed in larger studies.

Keywords: CAPRA-S score; biochemical failure; circulating tumour cells; micrometastasis; minimal residual disease; prostate cancer.