Health care disparities among octogenarians and nonagenarians with stage II and III rectal cancer

Abstract

Background: Octogenarians and nonagenarians with stage II/III rectal adenocarcinomas are underrepresented in the randomized trials that have established the standard-of-care therapy of preoperative chemoradiation followed by definitive resection (ie, chemoradiation and then surgery [CRT+S]). The purpose of this study was to evaluate the impact of therapies on overall survival (OS) for patients with stage II/III rectal cancers and determine predictors of therapy within the National Cancer Data Base (NCDB).

Methods: In the NCDB, patients who were 80 years old or older and had clinical stage II/III rectal adenocarcinoma from 2004 to 2013 were queried. Kaplan-Meier analysis, log-rank testing, logistic regression, Cox proportional hazards regression, interaction effect testing, and propensity score-matched analysis were conducted.

Results: The criteria were met by 2723 patients: 14.9% received no treatment, 29.7% had surgery alone, 5.0% underwent short-course radiation and then surgery (RT+S), 45.3% underwent CRT+S, and 5.1% underwent surgery and then chemoradiation (S+CRT). African American race and residence in a less educated county were associated with not receiving treatment. Male sex, older age, worsening comorbidities, and receiving no treatment or undergoing surgery alone were associated with worse OS. There was no statistical difference in OS between RT+S, S+CRT, and CRT+S. Interaction testing found that CRT+S improved OS independently of age, comorbidity status, sex, race, and tumor stage. In the propensity score-matched analysis, CRT+S was associated with improved OS in comparison with surgery alone.

Conclusions: A significant portion of octogenarians and nonagenarians with stage II/III rectal adenocarcinomas do not receive treatment. African American race and living in a less educated community are associated with not receiving therapy. This series suggests that CRT+S is a reasonable strategy for elderly patients who can tolerate therapy. Cancer 2017;123:4325-36. © 2017 American Cancer Society.

Keywords: chemotherapy and radiation therapy; geriatric oncology; health care disparities; rectal cancer; total mesorectal excision.

Conflict of interest statement

Conflicts of Interest/Disclosures: None

© 2017 American Cancer Society.

Figures

Figure 1. Overall survival amongst elderly rectal adenocarcinoma patients stratified by treatment received: chemoradiation then surgery, surgery the chemoradiation, short-course radiation then surgery, surgery alone, and no treatment

Kaplan-Meier curve showing the overall survival (OS) estimates of the entire cohort of patients as stratified by treatment group, with the number at risk below the x-axis. Among all patients, the 3 and 5-year overall survival estimated rates for patients receiving CRT+S were 69.0% (95% CI 65.9–71.9%) and 49.6% (95% CI 45.7–53.3%) respectively. The 3 and 5-year overall survival estimated rates for patients receiving surgery then chemoradiation were 60.5% (95%CI: 50.8–68.9%) and 47.4% (36.9%–57.2%) respectively. The 3 and 5-year survival estimated rates for patients receiving short-course radiation followed by surgery were 52.7% (95%CI: 42.8–61.7%) and 36.0% (95%CI: 26.3–45.7%) respectively. The 3 and 5-year overall survival estimated rates for patients receiving definitive surgery alone were 40.3% (95% CI: 36.5–44.1%) and 24.3% (95%CI: 20.6–28.1%) respectively. The 3 and 5-year overall survival estimated rates for patients not receiving therapy of were 9.1% (95% CI 6.3–12.6%) and 5.7% (95% CI 3.5–8.8%) respectively.

Figure 2. Overall survival amongst elderly rectal adenocarcinoma patients on propensity-score matched analysis comparing surgery alone versus chemoradiation followed by surgery

Kaplan-Meier curve showing the overall survival (OS) estimates of the propensity-score matched cohort of patients as stratified by surgery alone versus chemoradiation followed by surgery, with the number at risk below the x-axis. The 3 and 5-year overall survival estimated rates for patients receiving surgery alone were 42.1% (95%CI: 37.6–46.4%) and 23.5% (95%CI: 19.2%–28.1%) respectively. The 3 and 5-year overall survival estimated rates for patients receiving chemoradiation followed by surgery were 66.2% (95%CI: 61.9–70.2%) and 44.5% (95%CI: 39.4%–49.5%) respectively.