A population-based study of factors associated with systemic treatment in advanced prostate cancer decedents

Abstract

Introduction: Life-prolonging therapies (LPTs) are rapidly evolving for the treatment of advanced prostate cancer, although factors associated with real-world uptake are not well characterized.

Methods: In this cohort of prostate-cancer decedents, we analyzed factors associated with LPT access. Population-level databases from Ontario, Canada identified patients 65 years or older with prostate cancer receiving androgen deprivation therapy and who died of prostate cancer between 2013 and 2017. Univariate and multivariable analyses assessed the association between baseline characteristics and receipt of LPT in the 2 years prior to death.

Results: Of 3575 patients who died of prostate cancer, 40.4% (n = 1443) received LPT, which comprised abiraterone (66.3%), docetaxel (50.3%), enzalutamide (17.2%), radium-223 (10.0%), and/or cabazitaxel (3.5%). Use of LPT increased by year of death (2013: 22.7%, 2014: 31.8%, 2015: 41.8%, 2016: 49.1%, and 2017: 57.9%, p < 0.0001), driven by uptake of all agents except docetaxel. Adjusted odds of use were higher for patients seen at Regional Cancer Centers (OR: 1.8, 95% CI: 1.5-2.1) and who received prior prostate-directed therapy (OR: 1.3, 95% CI: 1.0-1.5), but lower with advanced age (≥85: OR: 0.54, 95% CI:0.39-0.75), increased chronic conditions (≥6: OR: 0.62, 95% CI: 0.43-0.92), and long-term care residency (OR: 0.38, 95% CI: 0.17-0.89). Income, stage at presentation, and distance to the cancer center were not associated with LPT uptake.

Conclusion: In this cohort of prostate cancer-decedents, real-world uptake of novel prostate cancer therapies occurred at substantially higher rates for patients receiving care at Regional Cancer Centers, reinforcing the potential benefits for treatment access for patients referred to specialist centers.

Keywords: decedent; life-prolonging therapy; prostate cancer; regional cancer center.

FIGURE 1

Proportion of patients receiving any Life‐Prolonging Therapy (LPT) prior to their death. Represented as % of all patients in our cohort who received any LPT prior to their death (black), % of patients who were registered at a Regional Cancer Center and received any LPT (red), and % of patients whose care occurred outside a Regional Cancer Center and received LPT (gray). Data are stratified by year of death.

FIGURE 2

Uptake of Life‐Prolonging Therapy (LPT) is driven by novel agents. Represented as the percentage of receipt of each therapy for all patients in the cohort that received any type of LPT prior to death, stratified by year of death. Those who did not receive LPT were excluded. The following agents are included: abiraterone (black circle), enzalutamide (red circle), docetaxel (green triangle), cabazitaxel (pink triangle), and radium‐223 (gray square).

FIGURE 3

Uptake of life‐prolonging therapy (LPT) at Regional Cancer Centers is brisker and to a greater percentage of patients than at non‐Regional Cancer Center sites. This represents the percentage of all patients in the cohort who received each type of LPT, stratified by year of death. The types of LPT included are abiraterone (top left), enzalutamide (top right), docetaxel (middle left), cabazitaxel (middle right), and radium‐223 (bottom left). The red circle represents uptake for patients who were registered for care at a Regional Cancer Center, and the black circle represent uptake for patients who were not registered at a Regional Cancer Center.