Assessment and treatment of breakthrough cancer pain: from theory to clinical practice.

Breakthrough cancer pain (BTcP) is a common condition in oncological patients. However, its management is still suboptimal. Improved knowledge of BTcP and its management in clinical practice may have immediate importance for all physicians involved in the supportive care of cancer patients. This review critically discusses the most important concepts for the correct diagnosis of BTcP and presents some intriguing cases of the management of this condition in clinical practice. Overall, the most appropriate therapeutic choice appears to be a rapid-onset opioid (ROO), and in particular, the nasal route of administration is the quickest and most convenient mode of administration for the management of BTcP, especially when the patient needs rapid resolution of pain. To this end, intranasal fentanyl spray may have a particular relevance in clinical practice. Future research should focus on accepted definitions of BTcP to investigate the optimal management of this highly heterogeneous pain condition. Therapeutic decision-making of patients, clinicians, and payers will likely be driven from results of well-designed clinical trials of ROOs.