Trends in survival based on treatment modality in patients with pancreatic cancer: a population-based study

Background

Pancreatic cancer (pcc) is one of the most lethal types of cancer, and surgery remains the optimal treatment modality for patients with resectable tumours. The objective of the present study was to examine and compare trends in the survival rate based on treatment modality in patients with pcc.

Methods

This population-based retrospective analysis included all patients with known-stage pcc in Ontario between 2007 and 2015. Flexible parametric models were used to conduct the survival analysis. Survival rates were calculated based on treatment modality, while adjusting for patient- and tumour-specific covariates.

Results

The study included 6437 patients. We found no noticeable improvement in survival for patients with stage iii or iv tumours; however, for stage i disease, the 1-, 2-, and 5-year survival rates increased over time to 81% from 51%, to 71% from 35%, and to 61% from 22% respectively. Most improvements were seen for surgical modalities, with 2-year survivals increasing to 89% from 65% for distal pancreatectomy (dp) without radiation (rt) or chemotherapy (ctx), to 65% from 37% for dp plus rt or ctx, to 60% from 44% for Whipple-only, and to 50% from 36% for Whipple plus rt or ctx. Lastly, 5-year survival improved to 81% from 52% for dp only, to 41% from 12% for dp plus rt or ctx, to 49% from 25% for Whipple-only, and to 26% from 12% for Whipple plus rt or ctx.

Conclusions

Most cases of pcc continue to be diagnosed at a late stage, with poor short-term and long-term prognoses. After adjustment for patient age, sex, and year of diagnosis, the survival for stage i tumours and for surgical modalities increased over time. Further research is needed to identify the reasons for improvement in survival during the study period.

Long-term trends in the incidence and relative survival of pancreatic cancer in Canada: A population-based study

BACKGROUND/OBJECTIVE

The poor survival among pancreatic cancer patients accounts for a disproportionate number of cancer deaths, and there has been little or no improvement in the long-term survival of these patients. This study examines the long-term trends in incidence and relative survival of patients diagnosed with pancreatic cancer in Canada between 1992 and 2008.

METHODS

We used pancreatic cancer data from the Canadian Cancer Registry. Incidence rate per age group was estimated over the aforementioned period. A flexible parametric model was used to estimate trends in one- and five-year relative survival for each age group and sex. Excess mortality rate was estimated to illustrate additional mortality due to a cancer diagnosis.

RESULTS

In total, 34,577 patients with pancreatic cancer were identified, of which 49.3% were male. Mean age at diagnosis was 70.1 (SD = 12.3) years. Approximately 60.0% of patients were older than 70 years at diagnosis. There has been no change in the incidence rate of pancreatic cancer in Canada; however, it significantly decreased for men (80+) (p = 0.011). Although one-year relative survival increased over time for all patients, five-year relative survival increased only 5% for the youngest age group (<50 years).

CONCLUSIONS

Overall survival of patients with pancreatic cancer remains low, although advances in chemotherapy and palliative care may have provided some improvement. Excess mortality remains highest shortly after diagnosis, which is likely attributable to the late diagnosis of pancreatic cancer.