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Breakthrough pain (BKP) is a transitory flare of pain that occurs on a background of relatively well controlled baseline pain. Previous surveys have found that BKP is highly prevalent among patients with cancer pain and predicts more severe pain, pain-related distress and functional impairment, and relatively poor quality of life. An international group of investigators assembled by a task force of the International Association for the Study of Pain (IASP) evaluated the prevalence and characteristics of BKP as part of a prospective, cross-sectional survey of cancer pain. Fifty-eight clinicians in 24 countries evaluated a total of 1095 patients with cancer pain using patient-rated items from the Brief Pain Inventory (BPI) and observer-rated measures. The observer-rated information included demographic and tumor-related data, the occurrence of BKP, and responses on checklists of pain syndromes and pathophysiologies. The clinicians reported BKP in 64.8% of patients. Physicians from English-speaking countries were significantly more likely to report BKP than other physicians. BKP was associated with higher pain scores and functional interference on the BPI. Multivariate analysis showed an independent association of BKP with the presence of more than one pain, a vertebral pain syndrome, pain due to plexopathy, and English-speaking country. These data confirm the high prevalence of BKP, its association with more severe pain and functional impairment, and its relationship to specific cancer pain syndromes. Further studies are needed to characterize subtypes of BKP. The uneven distribution of BKP reporting across pain specialists from different countries suggests that more standardized methods for diagnosing BKP are needed.

A number of symptoms cause physical or mental distress and suffering in the terminal and dying patient. In this prospective study of 117 patients (96% with a cancer diagnosis) in a Danish hospice all symptoms causing distress were assessed daily in three degrees of severity. The ten most frequently recorded symptoms were: fatigue, pain, weakness, dyspnoea, immobility/paresis, anorexia, general malaise, nausea/vomiting, oedema and amnesia. Fatigue was registered on 60.9% of the admission days, pain on 27.3%, dyspnoea on 19.2% and nausea/vomiting on 8.5%. The prevalence of pain, dyspnoea, nausea/vomiting, thirst and anxiety did not increase during the last seven days of life. Unconsciousness occurred in 23% of the patients during the last 24 hours and in 5% on the day before.

The causes of pain were analysed in 200 patients referred to a multidisciplinary pain clinic for cancer patients. In 158 patients, pain caused directly by tumour growth was found, 116 patients had pain secondary to the cancer disease or treatment while 33 patients had pain caused by factors unrelated to the cancer disease. The patients had many different combinations of causes of pain and the majority had more than one cause of pain. At the first contact and after treatment for 1-2 weeks, the patients were asked whether they had pain on movement, at rest or pain which interrupted sleep. After treatment for 1-2 weeks and after treatment for more than two weeks, the patients assessed the relief of pain obtained (none, slight, moderate, considerable, complete). The majority of patients achieved relief of pain at rest and during sleep while movement was still accompanied by pain in a number of patients. The majority of patients considered that the relief of pain obtained was moderate or considerable. Treatment consisted of adjustment of medication, blockades and epidural opioids supplemented by psychological intervention and help from social workers in selected patients.

Causes of pain were analysed in 200 patients referred to a specialized cancer pain clinic. Pain caused by tumour growth was found in 158 patients, pain secondary to cancer or its treatment in 116 patients and pain unrelated to cancer in 33 patients. Visceral involvement (74 cases), bone metastases (68 cases), soft tissue invasion (56 cases) and nerve/plexus pressure or infiltration (39 cases) were the most frequent causes of pain due to tumour growth. Myogenic pain (68 cases) was the most frequent cause of secondary pain. The patients presented with a multitude of different combinations of causes of pain, the majority having at least two separate causes. Since pain treatment in cancer patients should be determined by its aetiology, a detailed analysis of the pain condition in each patient should form the basis for a rational therapy.

1 Twenty-seven patients with moderate to severe chronic pain of malignant origin received buprenorphine (0.3 mg) and morphine (10 mg) intramuscularly in a double-blind, single dose within patient study. 2 Efficacy analysis demonstrated no significant differences in the peak analgesic effects or in the time to reach these effects. However, buprenorphine had a significantly longer duration of action than morphine. 3 Sedation was the most frequent unwanted effect with a similar incidence following each treatment. Buprenorphine was associated with a significantly higher incidence, greater severity, earlier onset, and longer duration of dizziness, nausea and vomiting than morphine. 4 Following both treatments there were small but significant decreases in pulse rate, blood pressure, and respiratory rate.

A retrospective investigation was undertaken of 48 cancer patients receiving long-term treatment with high dosages of epidural opioids. Prior to introduction of the epidural catheter, the patients were in stable oral opioid treatment (median dose: 300 mg morphine/24 hours, range 40-1,360). The effect of stable epidural opioid treatment (median dose: 90 mg morphine/24 hours, range 16-600) in the first catheter was assessed as good in 20, reasonable in 14 and poor in 13. The effect could not be assessed in one patient. Twenty-nine patients could be assessed on pure and stable epidural opioid treatment. The effect was good in 14, reasonable in seven and poor in eight. If the patients were subdivided according to the type of pain, 16 had somatic and/or visceral types of pain while 13 had neurogenic pain. Epidural opioid treatment of neurogenic pain was found to produce statistically significantly poorer results than in the case of somatic/visceral pain (p less than 0.05). At the time of assessment, no statistically significant difference was present in the epidural opioid dosage between the groups. The patients were subdivided into a low dosage group and a high dosage group. The low dosage group comprised patients who had received oral opioid treatment with less than 300 mg morphine/24 hours and the high dosage group comprised patients who received equal or greater than 300 mg morphine/24 hours. Epidural opioid treatment was found to provide statistically significantly better results in the low dosage group (p less than 0.05). In this group, a tendency to better relief of neurogenic pain was observed as compared with the high dosage group. At the time of assessment, no statistically significant difference was present in the epidural opioid dosage between the high dosage and low dosage groups.(ABSTRACT TRUNCATED AT 250 WORDS)