No clinical evidence was found to support a relationship between opioid prescriptions used to manage pain and risk of breast cancer recurrence, according to an article published online in the journal Cancer.
A total of 34,188 patients with incident, early stage breast cancer diagnosed between 1996 and 2008 in Denmark were identified from the Danish Breast Cancer Cooperative Group Registry. Data regarding opioid prescriptions were gathered from the Danish National Prescription Registry.
Results showed no correlation between ever-use of opioids (regardless of opioid type, strength, chronicity of use, or cumulative dose) and breast cancer recurrence (crude hazard ratio [HR], 0.98; 95% CI: 0.90, 1.1; adjusted HR, 1.0; 95% CI: 0.92, 1.1).
Furthermore, breast cancer recurrence rates were reduced among patients who used strongly (but not weakly) immunosuppressive opioids. The authors noted this could have possibly been due to channeling bias among those with a high competing risk.
The study argued the findings were important for patients with cancer given that opioids are commonly used to manage pain related to comorbid conditions.
Cronin-Fenton, D. P., Heide-Jørgensen, U., Ahern, T. P., Lash, T. L., Christiansen, P. M., Ejlertsen, B., Sjøgren, P., Kehlet, H. and Sørensen, H. T. (2015), Opioids and breast cancer recurrence: A Danish population-based cohort study. Cancer.