Survival in population-based pancreatic cancer patients: San Francisco Bay area, 1995-1999

Abstract

Patient vital status generally is passively obtained by cancer registries, and no previous population-based studies have used extensive active follow-up to compute a more accurate overall survival rate for pancreatic cancer. Therefore, the authors used multiple active and passive follow-up methods to determine vital status and date of death for 1,954 pancreatic cancer patients diagnosed from 1995 to 1999 in a large population-based study in the San Francisco Bay Area, California. Survival rates were estimated by using Kaplan-Meier methods. Hazard ratios and 95% confidence intervals were estimated by using multivariable Cox proportional-hazards models. Vital status was confirmed for >99% of 1,954 patients. The overall 5-year survival rate was 1.3% and was greater in patients who were younger and who had localized disease, well-differentiated tumors, and surgical resection. Shorter survival was associated with older age at diagnosis, male sex, distant/metastatic disease, and poorly differentiated tumors. Longer survival was observed for Asian/Pacific Islanders compared with non-Hispanic whites and for any active treatment regardless of tumor stage. With an almost complete follow-up, the authors observed a low overall 5-year survival rate. Although the results provide further evidence of poor survival among patients with pancreatic cancer, the data also suggest that within-stage-of-disease patients survived somewhat longer with therapy.

Figure 1.

Ascertainment and confirmation of vital status and date of death for 1,954 incident pancreatic cancer patients, 21–85 years of age at diagnosis in 1995–1999 in 6 San Francisco Bay Area counties of California. SEER, Surveillance, Epidemiology, and End Results; SSDI, Social Security Death Index.

Figure 2.

Product-limit survival curves for survival probability (y-axis), by survival in months (x-axis), associated with tumor stage (local: solid line; regional: dashed line; distant: dash-dot-dash line; unknown: long dash-short dash line, San Francisco Bay Area, California, 1995–1999.

Figure 3.

Product-limit survival curves for survival probability (y-axis), by survival in months (x-axis), associated with tumor grade (well/moderate-well differentiation: solid line; moderate differentiation: dashed line; moderate-poor/poor differentiation: dash-dot-dash line; unknown differentiation: long dash-short dash line), San Francisco Bay Area, California, 1995–1999.

Figure 4.

Product-limit survival curves for survival probability (y-axis), by survival in months (x-axis), associated with surgical resection (no surgical: solid line; surgical: dashed line), San Francisco Bay Area, California, 1995–1999.