Disparities by Race, Age, and Sex in the Improvement of Survival for Major Cancers: Results From the National Cancer Institute Surveillance, Epidemiology, and End Results (SEER) Program in the United States, 1990 to 2010

Abstract

Importance: Substantial progress has been made in cancer diagnosis and treatment, resulting in a steady improvement in cancer survival. The degree of improvement by age, race, and sex remains unclear.

Objective: To quantify the degree of survival improvement over time by age, race, and sex in the United States.

Design, setting, and participants: Longitudinal analyses of cancer follow-up data from 1990 to 2010, from 1.02 million patients who had been diagnosed as having cancer of the colon or rectum, breast, prostate, lung, liver, pancreas, or ovary from 1990 to 2009 and who were included in 1 of 9 population-based registries of the National Cancer Institute Surveillance, Epidemiology, and End Results (SEER) program.

Main outcomes and measures: Hazard ratios (HRs) and 95% CIs for cancer-specific death were estimated for patients diagnosed as having any of these cancers during 1995 to 1999, 2000 to 2004, and 2005 to 2009, compared with those diagnosed in 1990 to 1994.

Results: Significant improvements in survival were found for cancers of the colon or rectum, breast, prostate, lung, and liver. Improvements were more pronounced for younger patients. For patients aged 50 to 64 years and diagnosed from 2005 to 2009, adjusted HRs (95% CIs) were 0.57 (95% CI, 0.55-0.60), 0.48 (95% CI, 0.45-0.51), 0.61 (95% CI, 0.57-0.69), and 0.32 (95% CI, 0.30-0.36), for cancer of the colon or rectum, breast, liver, and prostate, respectively, compared with the same age groups of patients diagnosed during 1990 to 1994. However, the corresponding HRs (95% CIs) for elderly patients (those 75-85 years old) were only 0.88 (95% CI, 0.84-0.92), 0.88 (95% CI, 0.82-0.95), 0.76 (95% CI, 0.69-0.84), and 0.65 (95% CI, 0.61-0.70), for the same 4 cancer sites, respectively. A similar, although weaker, age-related period effect was observed for lung and pancreatic cancers. The adjusted HRs (95% CIs) for lung cancer were 0.75 (95% CI, 0.73-0.77) and 0.84 (95% CI, 0.81-0.86), respectively, for patients aged 50 to 64 years and 75 to 85 years diagnosed between 2005 and 2009, compared with the same age groups of patients diagnosed between 1990 and 1994 (0.73 [95% CI, 0.69-0.77] and 0.90 [95% CI, 0.85-0.95], respectively. Compared with whites or Asians, African Americans experienced greater improvement in prostate cancer survival. From 1990 to 2009, ovarian cancer survival declined among African Americans but improved among whites. No apparent sex difference in the degree of improvement for any non-sex-specific cancer was noted.

Conclusions and relevance: Younger patients experienced greater benefit from recent oncology advances than elderly patients. African Americans experienced poorer survival than whites for all cancers, and the racial difference decreased for prostate cancer but increased for ovarian cancer. Identifying factors associated with varied improvement in cancer survival can inform future improvements in cancer care for all.

Figure 1

Multivariate-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for cancer-specific death associated with year of diagnosis according to race, nine SEER registries, 1990–2009. HRs and 95% CIs for white (green line), African American (red line), and Asian (purple line) were adjusted for marital status, common histology types, SEER registry sites, SEER historic stage, age, and sex (if applicable), using time period 1990–1994 as the reference. P-values for interaction for year of diagnosis and race are presented. (A) Colorectal cancer, P = 0.44; (B) Breast cancer (women only), P = 0.15; (C) Liver/Intrahepatic bile duct cancer, P = 0.75; (D) Lung cancer, P = 4.31×10⁻³; (E) Pancreatic cancer, P = 0.11; (F) Prostate cancer, P = 4.57×10⁻⁶; (G) Ovarian cancer, P = 1.41×10⁻⁵.

Figure 2

Multivariate-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for cancer-specific death associated with year of diagnosis according to age at diagnosis, nine SEER registries, 1990–2009. HRs and 95% CIs were adjusted for marital status, common histology types, SEER registry sites, SEER historic stage, race, and sex (if applicable), using the time period 1990–1994 as the reference. Age 20–49, black line; 50–64, purple line; 65–74, green line; 75–85, red line. P-values for interaction for year of diagnosis and age groups are presented. (A) Colorectal cancer, P = 4.78×10⁻⁴²; (B) Breast cancer (women only), P = 1.18×10⁻⁴⁹; (C) Liver/Intrahepatic bile duct cancer, P = 0.006; (D) Lung cancer, P = 7.76×10⁻¹⁰; (E) Pancreatic cancer, P = 7.43×10⁻⁶; (F) Prostate cancer, P = 3.58 ×10⁻⁸⁹; (G) Ovarian cancer, P = 0.10.

Figure 3

Multivariate-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for cancer-specific death associated with per 5-year increment in year of diagnosis by cancer stage at diagnosis (localized, regional, and distant), according to age at diagnosis, nine SEER registries, 1990–2009. HRs and 95% CIs were adjusted for marital status, common histology types, SEER registry sites, SEER historic stage, race, and sex (if applicable), using the time period 1990–1994 as the reference. Localized stage: blue line, regional stage: red line, and distant stage: black line. P-values for heterogeneity across cancer stages are presented. (A) Colorectal cancer, P = 0.06; (B) Breast cancer (women only), P = 0.02; (C) Liver/Intrahepatic bile duct cancer, P = 0.23; (D) Lung cancer, P = 0.01; (E) Pancreatic cancer, P = 0.16; (F) Ovarian cancer, P = 0.77.