Is the use of transdermal fentanyl inappropriate according to the WHO guidelines and the EAPC recommendations? A study of cancer patients in Italy.

BACKGROUND: World Health Organization (WHO) guidelines, Agency for Health Care Policy and Research (AHCPR) clinical practice guidelines, and EAPC recommendations indicate oral route of opioid administration as the preferred route. Transdermal administration of opioids is considered an alternative when patients cannot take medications orally. Moreover, WHO and EAPC indicate orally administered morphine as the first-choice drug for the treatment of moderate to severe cancer-related pain. However, we can see that in Italy there is an increasing use of transdermal fentanyl (TF) as first-choice strong opioid (and route) even when oral administration of opioids is possible.

AIMS: The aims of this study are to describe the modality in the use of TF administration in two settings of care, taking into consideration (1) the drugs previously taken by the patients, (2) the reasons for switching from any drug to TF, (3) the conversion ratio used, and (4) the frequency of "inappropriate use of transdermal fentanyl according to the WHO guidelines and the EAPC recommendations", i.e., switching to fentanyl patch from any drug, even if there were no contraindications in using oral morphine. The settings of care considered were the out-patient palliative care unit (OP-PCU) and the oncological wards (OWs) of the National Cancer Institute (NCI) of Milan.

PATIENTS AND METHODS: The clinical charts of 98 patients prescribed with and given fentanyl patch for the first time at the NCI of Milan in 2002 were reviewed and the data gathered were grouped according to the administration of fentanyl at the OP-PCU (63 out-patients) or at the OWs (35 in-patients). Summary descriptive statistics and bar and box plots have been used. Fisher two-tailed exact text was applied to test the differences between in- and out-patients.

RESULTS: Before switching to TF, (1) in-patients were more frequently treated with nonsteroidal anti-inflammatory drugs (NSAIDs) and weak opioids (mostly tramadol) in respect to the out-patients (44.1 vs 25.8%) who were mostly treated with oral morphine (48.4 vs 20.6%) (p=0.045), and (2) 88.7% of the out-patients were treated with oral opioids and only 1.6% with parenteral opioids in respect to OWs where 69.7% were on oral opioids and 18.2% on parenteral opioids (p=0.006). In 29% of out-patients and in 53% of in-patients, changing to fentanyl patch was considered as "inappropriate" (p=0.028) according to the WHO guidelines and the EAPC recommendations. No statistically significant differences between the two settings were observed regarding the reasons for switching and the conversion ratio used.

CONCLUSIONS: There is a trend to use fentanyl patch as first-choice strong opioid in cancer patients in situations such as titration phase, in the presence of instable pain, and in the absence of dysphagia or gastrointestinal symptoms where the use of oral morphine is, however, not contraindicated.