Type II diabetes associated with decreased survival in pancreatic cancer

1. Long-standing type II diabetes mellitus in patients with pancreatic cancer is associated with decreased survival compared to non-diabetics.

2. No differences in survival were observed in patients with recent onset diabetes (<4 years prior to cancer diagnosis).

Evidence Rating Level: 3 (Average)

Study Rundown: Pancreatic cancer is the fourth leading cause of cancer mortality in the United States with a median survival of <12 months post-diagnosis. Type II diabetes mellitus (T2DM) is associated with a number of systemic metabolic and inflammatory changes, and has been observed to contribute both as a risk factor for the development of pancreatic cancer as well as a clinical marker of sub-clinical pancreatic cancer. However, the relationship between T2DM and pancreatic cancer survival is not well established. The purpose of this study was to evaluate the impact of long-standing T2DM on overall pancreatic cancer survival.

The study analyzed pancreatic cancer survival stratified by T2DM status from 2 large prospective community patient databases and a third ongoing, clinic-based database. Overall, over 1300 pancreatic patients were included in the analysis. At the conclusion of the study, the authors found that long-standing T2DM, defined as diagnosis 4 years or more prior to the diagnosis of cancer, was associated with decreased survival compared to non-diabetic patients. The effect remained significant after adjustments for confounders and co-morbid conditions. However, recent onset T2DM (diagnosis less than 4 years prior to cancer), did not demonstrate a significant decrease in survival. The study was strengthened by its the large sample size and the use of prospective population cohorts, which captured a large spectrum of patients with varying degrees of disease aggressiveness. The results of this study support the use of long-standing T2DM as a prognostic factor in pancreatic cancer. However, it should be noted that the population cohort was primarily composed of patients of European descent which may reduce the generalizability to other patient populations.

Click to read the study in the JCO (Journal of Clinical Oncology)

Relevant Reading: Type II diabetes and pancreatic cancer: a meta-analysis of 36 studies

In-Depth [prospective cohort]: This study collected data from 3 prospective cohort studies, the Nurses’ Health Study (NHS), the Health Professionals Follow-Up Study (HPFS), and a third ongoing prospective clinic-based case series. Eligible patients had pathologically confirmed pancreatic adenocarcinoma; a total of 635, 371, and 386 pancreatic cancer patients were enrolled from each of these studies, respectively. In all 3 studies, over 90% of the patient population self-identified as white. In the NHS and HPFS studies, patients with long-term T2DM demonstrated a 40-50% reduction in overall survival compared to non-diabetics (median survival times of 3 months for T2DM compared to 5 months for non-diabetics); the HR for overall mortality was 1.40 (95% CI: 1.15-1.69, p<0.001). The result remained significant after adjustments for propensity scores for varying difference in comorbidities (HR: 1.46; 95% CI: 1.17-1.80, p<0.001). In the prospective clinic-based trial, a similar survival reduction were seen among patients with T2DM (9 months versus 13 months in non-diabetics) with a HR of 1.53 (95% CI: 1.07-2.20, p=0.02). There was no statistically significant association of recent onset T2DM (diagnosis <4 years) with survival vs non-diabetics (HR: 1.12; 95% CI: 0.90-1.39).

More from this author: Rituximab linked with reduced chronic immune disease following stem cell transplantation, High-dose prophylaxis for hemophilia increases costs with minimal benefit, Ambrisentan found ineffective against idiopathic pulmonary fibrosis

Image: PD

©2014 2 Minute Medicine, Inc. All rights reserved. No works may be reproduced without expressed written consent from 2 Minute Medicine, Inc. No article should be construed as medical advice and is not intended as such by the authors, editors, staff or by 2 Minute Medicine, Inc.