Abstract
Breakthrough cancer pain (BTcP) is a complex and variegate phenomenon that may change its presentation during the course of patients' disease in the same individual. An appropriate assessment is fundamental for depicting the pattern of BTcP. This information is determinant for a personalized management of BTcP. The use of opioids as needed is recommended for the management of BTcP. There are several options which should be chosen according to the individual pattern of BTcP. In general, a drug with a short onset and offset should be preferred. Although oral opioids may still have specific indications, fentanyl products have been found to be more rapid and effective. The most controversial point regards the opioid dose to be used. The presence of opioid tolerance suggests to use a dose proportional to the dose used for background analgesia. In contrast, regulatory studies have suggested to use the minimal available dose to be titrated until the effective dose. Further large studies should definitely settle this never ended question.