Breakthrough Cancer Pain Clinical Features and Differential Opioids Response: A Machine Learning Approach in Patients With Cancer From the IOPS-MS Study.

PURPOSE: A large proportion of patients with cancer suffer from breakthrough cancer pain (BTcP). Several unmet clinical needs concerning BTcP treatment, such as optimal opioid dosages, are being investigated. In this analysis the hypothesis, we explore with an unsupervised learning algorithm whether distinct subtypes of BTcP exist and whether they can provide new insights into clinical practice. METHODS: Partitioning around a k-medoids algorithm on a large data set of patients with BTcP, previously collected by the Italian Oncologic Pain Survey group, was used to identify possible subgroups of BTcP. Resulting clusters were analyzed in terms of BTcP therapy satisfaction, clinical features, and use of basal pain and rapid-onset opioids. Opioid dosages were converted to a unique scale and the BTcP opioids-to-basal pain opioids ratio was calculated for each patient. We used polynomial logistic regression to catch nonlinear relationships between therapy satisfaction and opioid use. RESULTS: Our algorithm identified 12 distinct BTcP clusters. Optimal BTcP opioids-to-basal pain opioids ratios differed across the clusters, ranging from 15% to 50%. The majority of clusters were linked to a peculiar association of certain drugs with therapy satisfaction or dissatisfaction. A free online tool was created for new patients' cluster computation to validate these clusters in future studies and provide handy indications for personalized BTcP therapy. CONCLUSION: This work proposes a classification for BTcP and identifies subgroups of patients with unique efficacy of different pain medications. This work supports the theory that the optimal dose of BTcP opioids depends on the dose of basal opioids and identifies novel values that are possibly useful for future trials. These results will allow us to target BTcP therapy on the basis of patient characteristics and to define a precision medicine strategy also for supportive care.

Sex differences in the response to opioids for pain relief: A systematic review and meta-analysis.

There are conflicting results about sex differences in the response to opioids for pain control and the role of potential influencing factors of these differences has not been investigated. We meta-analyzed differences and similarities between men and women in opioid response for pain control and investigated the potential influence of baseline pain intensity, age, body weight, and other factors in these findings. PubMed, Scopus, and Cochrane CENTRAL were searched through January 15, 2019, for clinical studies in which opioids were administered for pain control. We included clinical studies in which (a) opioids were used to treat acute or chronic pain, (b) the response to opioids was broken down for men and women, and (c) the response to opioids was reported as (i) difference between baseline and final Visual Analog Scale of Pain Intensity (VASPI) score 30 min after opioid administration (Delta-VASPI at 30'), or daily dose of opioids (ii) self-administered by patients (patient-controlled analgesia PCA), or (iii) administered by physicians. Risk of bias was evaluated using ROBINS-I and the overall quality of evidence for primary outcomes was evaluated using the GRADE system. Globally, we included 40 comparisons (6794 patients). Regarding acute pain, we found moderate quality of evidence that women and men do not differ in their response to opioids 30 min after their administration [Delta-VASPI at 30': mean difference, MD = 0.42 (-0.07; 0.91)]. We also found moderate quality of evidence that women self-administer lower daily amounts of opioids [daily PCA: standardized mean difference, SMD = -0.30 (-0.41; -0.18)]. Regarding chronic pain, we found low quality of evidence that women receive lower daily doses for non-cancer pain [MD = -36.42 (-57.86; -14.99)]. By contrast, we found very low quality of evidence that women and men do not differ in the daily dose of opioids for cancer pain [MD = -16.09 (-40.13; 7.94)]. Age, comorbid mental disorders, type of administration, type of opioids, type of patients, and body weight significantly modified these results. In conclusion, the results of the present meta-analysis suggest that men and women may differ in the response to opioids for pain relief, but these differences as well as similarities are significantly influenced by factors like age and comorbid mental disorders. However, the role of these factors is not usually evaluated in the prescription of opioids for pain control. There is an urgent need to conduct clinical trials on the use of opioid medications for pain, in which information about all possible influencing factors are provided and broken down for men and women.

Factors Influencing the Clinical Presentation of Breakthrough Pain in Cancer Patients.

Background: The aim of this study was to identify potential variables influencing the clinical presentation of breakthrough cancer pain (BTP). Methods: Cancer patients with a diagnosis of BTP were enrolled. Demographic and clinical characteristics, as well as background pain and BTP characteristics were collected. Multivariate analyses were conducted to assess the correlation between BTP characteristics and the variables examined. Results: Data of 4016 patients were analysed. Average daily number of BTP episodes was 2.4, mean intensity was 7.5, and a mean duration was 43.3 min. A short onset BTP was observed in 68.9% of patients. In 30.5% of patients BTP was predictable. There were 86.0% of participants who reported a marked interference of BTP with their daily activities. Furthermore, 86.8% of patients were receiving opioids for the management of BTP. The average time to meaningful pain relief was 16.5 min and 70.9% of patients were satisfied with their BTP medications. Age, head and neck cancer, Karnofsky, background pain intensity, predictable and fast onset BTP were independently associated with the number of BTP episodes. BTP pain intensity was independently associated with background pain intensity, fast onset BTP, and Karnofsky. Neuropathic pain mechanism was independently associated with unpredictable BTP. Variables independently associated with a longer duration of BTP were age, place of visit, cancer diagnosis, disease-oriented therapy, background pain intensity and mechanism, and unpredictable BTP. Age, Karnofsky, background pain intensity, fast onset, and long duration of BTP were independently associated with interference with daily activity. Conclusions: BTP has a variable presentation depending on interdependent relationships among its different characteristics.

High dosage of a fixed combination oxycodone/naloxone prolonged release: efficacy and tolerability in patients with chronic cancer pain.

PURPOSE: Opioids are associated with side effects in the treatment of moderate-to-severe chronic cancer pain. Oral combination of opioid agonist-antagonist oxycodone-naloxone (OXN-PR) attenuates gastrointestinal side effects; however, evidence on high-dose OXN-PR treatment is scant. This study evaluates the efficacy and tolerability of high-dose OXN-PR in chronic cancer pain. PATIENTS AND METHODS: This was a multicenter, prospective 60-day observation on consecutive cancer patients with uncontrolled moderate-severe chronic pain or intolerant to other analgesics, who were switched at entry visit (T0) to OXN-PR ≥80 mg daily. Patients were reassessed 14, 30, 45, and 60 days later (T60). Primary endpoint of the study was analgesic response rate (decrease ≥30% of pain intensity from baseline, measured on a 0-10 numerical rating scale, NRS) after 30 days on OXN-PR. Additional endpoints assessed at every visit were the impact of pain on quality of life (QoL), breakthrough cancer pain (BTCP) episodes, opioid dosage escalation index, bowel dysfunction, safety, and other side effects. RESULTS: One hundred nineteen patients were included (age 64 ± 12, metastatic disease in 91.6%); 101 of them (84.9%) completed the 60-day observation. At T0, the majority had severe pain (NRS ≥7 in 79.8%; neuropathic features in 83.2%). Response rate at 30-day visit was 79.8% (n = 95). OXN-PR resulted in a significant reduction in pain over time (T0: 7.4 ± 1.3; T60: 3.3 ± 1.8; p < 0.001), and the number of daily (BTCP) declined (3.9 ± 2.2 vs. 2.0 ± 0.6, p < 0.001). Daily dosage of OXN-PR slightly increased (T0: 81.3 ± 6.0; T60: 93.6 ± 34.0; p < 0.001). The impact of pain on QoL abated (p < 0.0001), and bowel function improved overtime (p < 0.001). After the switch to OXN-PR, the number of patients complaining for side effects decreased overall (p < 0.0001); laxatives and antiemetic use also declined significantly. CONCLUSIONS: OXN-PR was highly effective and well tolerated even at high doses in cancer patients with chronic pain. The agonist-antagonist combination rapidly alleviated pain and its impact on life style, reducing the number of BTCP and improving opioid side effects.

Breakthrough Cancer Pain: Preliminary Data of The Italian Oncologic Pain Multisetting Multicentric Survey (IOPS-MS).

INTRODUCTION: An ongoing national multicenter survey [Italian Oncologic Pain multiSetting Multicentric Survey (IOPS-MS)] is evaluating the characteristics of breakthrough cancer pain (BTP) in different clinical settings. Preliminary data from the first 1500 cancer patients with BTP enrolled in this study are presented here. METHODS: Thirty-two clinical centers are involved in the survey. A diagnosis of BTP was performed by a standard algorithm. Epidemiological data, Karnofsky index, stage of disease, presence and sites of metastases, ongoing oncologic treatment, and characteristics of background pain and BTP and their treatments were recorded. Background pain and BTP intensity were measured. Patients were also questioned about BTP predictability, BTP onset (≤10 or >10 min), BTP duration, background and BTP medications and their doses, time to meaningful pain relief after BTP medication, and satisfaction with BTP medication. The occurrence of adverse reactions was also assessed, as well as mucosal toxicity. RESULTS: Background pain was well controlled with opioid treatment (numerical rating scale 3.0 ± 1.1). Patients reported 2.5 ± 1.6 BTP episodes/day with a mean intensity of 7.5 ± 1.4 and duration of 43 ± 40 min; 977 patients (65.1%) reported non-predictable BTP, and 1076 patients (71.7%) reported a rapid onset of BTP (≤10 min). Higher patient satisfaction was reported by patients treated with fast onset opioids. CONCLUSIONS: These preliminary data underline that the standard algorithm used is a valid tool for a proper diagnosis of BTP in cancer patients. Moreover, rapid relief of pain is crucial for patients' satisfaction. The final IOPS-MS data are necessary to understand relationships between BTP characteristics and other clinical variables in oncologic patients. FUNDING: Molteni Farmaceutici, Italy.

Narrative medicine to highlight values of Italian pain therapists in a changing healthcare system.

Until 2010 pain management in Italy was only partially covered and no structural and qualitative mapping had ever been realized. The VEDUTA project was designed to provide a tool to unite pain therapists in national cooperation. Quantitative questionnaires and narrative plots were sent to 350 Italian specialists; 184 therapists completed the first section and 87 also wrote their stories. Narratives were analyzed through transactional analysis and emotional intelligence. Overall, results show that a patient-centered approach is common in daily practice, but that bureaucracy is endangering quality of care. This cultural analysis, through both the application of quantitative assessment and narrative plots, provides a useful tool to improve those aspects of the system detrimental to the appropriate management of pain in Italy.

Hormone replacement therapy in morphine-induced hypogonadic male chronic pain patients.

BACKGROUND: In male patients suffering from chronic pain, opioid administration induces severe hypogonadism, leading to impaired physical and psychological conditions such as fatigue, anaemia and depression. Hormone replacement therapy is rarely considered for these hypogonadic patients, notwithstanding the various pharmacological solutions available. METHODS: To treat hypogonadism and to evaluate the consequent endocrine, physical and psychological changes in male chronic pain patients treated with morphine (epidural route), we tested the administration of testosterone via a gel formulation for one year. Hormonal (total testosterone, estradiol, free testosterone, DHT, cortisol), pain (VAS and other pain questionnaires), andrological (Ageing Males' Symptoms Scale-AMS) and psychological (POMS, CES-D and SF-36) parameters were evaluated at baseline (T0) and after 3, 6 and 12 months (T3, T6, T12 respectively). RESULTS: The daily administration of testosterone increased total and free testosterone and DHT at T3, and the levels remained high until T12. Pain rating indexes (QUID) progressively improved from T3 to T12 while the other pain parameters (VAS, Area%) remained unchanged. The AMS sexual dimension and SF-36 Mental Index displayed a significant improvement over time. CONCLUSIONS: In conclusion, our results suggest that a constant, long-term supply of testosterone can induce a general improvement of the male chronic pain patient's quality of life, an important clinical aspect of pain management.

Pain biomarkers.

The value of biomarkers in aiding early diagnosis of disease and predicting response to pharmacologic interventions is well known. The idea that biomarkers may also be used to identify and quantify pain has been investigated in preclinical and clinical studies. Findings from a preclinical study show that inflammatory pain and neuropathic pain have different biomarkers. Further investigations provided mixed results, on the one hand, cystatin C levels in cerebrospinal fluid appear to be a predictive marker for postherpetic neuralgia in patients with varicella-zoster virus, and a pain marker in women experiencing labour pain, but is not correlated with pain duration or intensity. Investigations into potential biomarkers for chest pain showed that cardiac markers used to aid in diagnosis and prognosis of cardiac disease correlate with tissue damage rather than with pain. Further studies are needed to gain insights into biomarkers for pain to enhance pain management practices.