Prevalence and characteristics of breakthrough pain in cancer patients: a pilot study

The aim of this study was to clarify the prevalence and characteristics of breakthrough pain in cancer patients. We conducted a cross-sectional survey of consecutive patients older than 20 years of age admitted to a University Hospital with a cancer diagnosis Breakthrough pain was defined as meeting all of the following criteria： Pain 1）with background pain present most of the time, 2）which is well controlled, 3）with short-lived episodes of exacerbation. One hundred and sixty-nine patients were recruited and 118（69.8％）completed the survey. Of these 118 patients, 11％（95％CI：7–18％）had breakthrough pain. Breakthrough pain occurred in 23％（14–35％）of patients with cancer-related pain and 29％（17–45％）of patients with pain from the cancer itself. Patients reported episodes occurring up to three times a day,a time to peak intensity of within 5 minutes, and a duration of untreated episodes of up to 15 minutes are 54％（29–77％）, 54％（29–77％）, 54％（29–77％）, respectively.