We examined whether survival for patients improved after opening Hoag Cancer Center in 1991. Data from the Hoag Hospital tumor registry from the successive eras 1986-1991 and 1992-1999 were used for historical intramural comparisons. Patients were diagnosed and/or treated at Hoag Hospital within four months of diagnosis. SEER (National Surveillance Epidemiology and End Results program) data were used for contemporary extramural survival comparisons of patients with invasive cancer in the successive eras. The methodology used by SEER was used for the survival analysis; so survival data is reported as relative survival, the ratio of observed survival for cancer patients to the expected survival for the general population with adjustments for competing causes of mortality based on age, race, and gender. Relative 5-year survival rates for Hoag patients with invasive cancer increased from 63% during 1986-1991 (n=5487, median age 65.0 years) to 71% during 1992-1999 (n=10,548, median age 65.8 years), and were higher for 22/24 distinct tumor types in the more recent era (p=.00005, T-Test). Relative 5-year survival rates improved for each of the four most prevalent cancers: breast (89% to 95%), prostate (92% to 100%), lung (20% to 24%), and colon (66 to 72%) and rectal cancers (68% to 83%). Hoag survival for all patients with invasive cancer was higher than SEER figures in both eras: 63% vs 58% during 1986-1991, and increased to 71% vs 64% during 1992-1999. Survival for Hoag patients was the same or higher than SEER figures for only 50% (12/24) of malignancies during 1986-1991 but increased to 87% (21/24) during 1992-1999 (p=.013 Fisher’s exact test; p=.001, T-Test). Intramural comparisons for 1992-1999 to 1986-1991 revealed a higher percentage of patients diagnosed and treated at Hoag (84.0% vs 81.2%), a higher percentage with local disease at diagnosis (50.8% vs 45.3%), a lower percentage treated by surgery alone (31.0% vs 36.9%), and greater use of biological response modifiers (6.7% vs 1.7%) (all p < .0001). The existence of the Hoag Cancer Center has been associated with improved survival for patients with invasive cancer. The major reasons for enhanced survival were earlier diagnosis, and substantial improvements in survival for regional disease in association with increased use of systemic treatment as part of combined modality therapy. The findings are consistent with the hypothesis that accelerated dissemination of new information resulted in earlier adoption of improved screening, diagnostic, and multidisciplinary treatment approaches that were associated with higher survival rates.
[Proc Amer Assoc Cancer Res, Volume 46, 2005]