Current Opinion in Supportive and Palliative Care

Editorial introductions No abstract available

Intrathecal therapy for pain in cancer patients Purpose of review Intrathecal drug delivery systems (IDDS) for cancer pain remain little employed despite a high level of efficiency even though the technique is widely recommended. This review aims to summarize recent advances in IDDS for cancer patients. Recent findings The respective roles of catheter positioning, volume and flow rate in diffusion of intrathecal treatments, as well as the individual roles of blood pressure, heart rate, and amplitude of the respiratory movements in cerebrospinal fluid (CSF) treatment dispersion, are now well established. Models are available using MRI data. Morphine has long been the gold standard in first line treatment, but recent publications conclude that ziconotide has largely proven its efficiency and that adverse effects are controllable. Four recent publications have evaluated cohorts of cancer patients treated by IDDS in 315 patients. All found a great efficiency of intrathecal treatment for cancer pain. Technical innovations include new catheters and anchorage devices for easier placement and a lower rate of complication. Three-dimensional (3D) CT scan appears to be a noninvasive technique for the diagnosis of catheter complications. Ultrasound should be used to locate pump septum for refill. Summary All recent recommendations highlight the efficiency of IDDS and propose to use it sooner.

Mindfulness-based interventions for cancer-related pain and depression: a narrative review of current evidence and future potential Purpose of review People with cancer commonly experience persistent pain and psychological distress. Interventions are needed which address the multifactorial nature of pain and depression, yet few studies have examined the impact of mindfulness-based interventions (MBIs) for cancer-related pain and depression. Recent findings MBIs for cancer-related pain and depression can be effectively delivered across a range of modalities and show promise for alleviating mood and some physical health symptoms, although not always pain. There is some evidence for the cost-effectiveness of MBIs. Summary The field of MBIs would benefit from greater methodological rigour and investigation into a broader range of cancer populations to increase the knowledge base and in turn the evidence base on which interventions can be developed to the benefit to patients with cancer-related pain and depression.

Opioids and breast cancer recurrence Purpose of review Breast cancer survival has improved motivating the need for better understanding of the sequelae of the disease and its treatments. Lab studies suggest opioids modify cancer cell growth but the association of opioids with cancer progression in humans is not clear. This review aims to summarize recent findings related to opioid use and breast cancer progression. Recent findings Opioid-sparing analgesia may be associated with better survival in cancer patients. In-vitro research suggests that treatment with μ-opioid receptor antagonists inhibits cancer proliferation, and shows some promise for attenuating tumor growth in humans, thereby enhancing survival. Prescription use of opioids does not appear to influence the risk of recurrence in patients, though the evidence comes from a single large registry-based observational study. Ongoing clinical trials are comparing opioid-sparing regional anesthesia with general anesthesia for the risk of breast cancer recurrence. Summary The association of opioids with breast cancer progression is controversial. Further observational studies are needed. There is currently no clear evidence to suggest that opioid use should be avoided in breast cancer patients because of concerns regarding the risk of breast cancer recurrence.

Where has the ‘bio’ in bio-psycho-social gone? Purpose of review Current definitions of pain do not necessitate tissue damage. This is important because it does justice to the pain patient in whom a nociceptive source is not detectable. However, in conjunction with exciting findings regarding supraspinal pain modulation and a (perceived) failure of identifying nociceptive sources in individual patients, this might have led to a devaluation of the role of nociception for chronic pain. In this review, the relative importance of nociception versus psychological factors for chronic pain is examined by scrutinizing the example of pain present several months following surgical joint replacement for severe osteoarthritis. Recent findings In most patients with chronic pain due to severe osteoarthritis, removal of the putative nociceptive source leads to pain elimination/reduction, indicating that their pain depended on nociceptive input. Furthermore, the influence of psychological factors on outcomes following joint replacement for severe osteoarthritis is limited: pain catastrophizing, which is the most consistently identified psychological factor influencing outcome, explains less than 10% of the variance of pain magnitude several months after knee replacement. The influence of psychological factors might be larger for pain disability than for pain magnitude, which could skew the perception of the importance of psychological factors. Summary It appears that the importance of nociception relative to psychological factors is often underestimated, at least in the instance of pain present several months following surgical joint replacement for severe osteoarthritis. Because this might apply also to other chronic pain patients, in particular those without disability, research should not neglect the investigation of nociceptive mechanisms, in particular how they might be detected clinically.

Assessment of conditioned pain modulation in healthy participants and patients with chronic pain: manifestations and implications for pain progression Purpose of review The purpose of this review is to summarize recent findings on conditioned pain modulation (CPM) in humans with a focus on methodology, factors modulating CPM, and the potential for CPM as a clinical marker for pain progression. Recent findings CPM can be evoked by combining different stimulus modalities with good reliability; sequential CPM effects are stable over time with limited carryover effects. Optimism and pain catastrophizing might influence pain inhibition. Further, studies suggest that the CPM effect can be improved by gabapentinoids, transcranial direct current stimulation to cortical structures, and exercise and that long-term opioid use might impair CPM in patients with chronic pain. Clinical evidence suggests that preoperative impaired CPM may predict more severe chronic postoperative pain. The effect of pain duration on CPM impairment has been challenged by recent studies. Summary As CPM methodology is optimized, studies are revealing factors that can modulate descending pain inhibitory pathways. Understanding underlying mechanisms of CPM will improve the utility of CPM in a clinical setting and potentially lead to personalized treatments for chronic pain patients.

Issues in the future development of new analgesic drugs Purpose of review There is a clear unmet need for either the development of new drugs for the treatment of painful pathologies or the better use of the existing agents denoted by the lack of efficacy of many existing drugs in a number of patients, limitations of their use due to severity of side effects, and by the high number of drugs that fail to reach clinical efficacy from preclinical development. This account considers the efforts being made to better validate new analgesic components and to improve translational efficacy of existing drugs. Recent findings A better use of the available models and tools can improve the predictive validity of new analgesic drugs, as well as using intermediate steps when translating drugs to clinical context such as characterizing drugs using stem cell-sensory derived neurones. Profiling patient sensory phenotypes can decrease the number of failed clinical trials and improve patient outcome. Summary An integrative approach, comprising the use of complementary techniques to fully characterize drug profiles, is necessary to improve translational success of new analgesics.

Editorial: Knowledge of gastrointestinal toxicity mechanisms is paving the way for improved assessment and management of patient supportive care No abstract available

The role of mucins in mucositis Purpose of review Alimentary mucositis is a severe dose limiting side effect of chemotherapy and radiotherapy. Mucin expression and secretion are associated with mucositis. This article aims to review current studies involving mucin and mucositis. Recent findings Mucins have been shown to alter mucositis severity and key targets associated with mucositis. First, interventions increasing mucin content has been associated with reduce damage associated with mucositis. Second, mucins have also been shown to protect microbiota from radiation-induced damage. Finally, mucins have also been shown to be involved in lumen epithelial barrier interactions altering signalling for cell proliferation, motility, and the inhibition of apoptosis. Summary The current studies suggest that mucin expression prior to and during mucositis may be very important in reducing the severity of mucositis and further research into the area is warranted.

Animal models of mucositis: critical tools for advancing pathobiological understanding and identifying therapeutic targets Purpose of review Mucositis remains a prevalent, yet poorly managed side effect of anticancer therapies. Mucositis affecting both the oral cavity and gastrointestinal tract predispose to infection and require extensive supportive management, contributing to the growing economic burden associated with cancer care. Animal models remain a critical aspect of mucositis research, providing novel insights into its pathogenesis and revealing therapeutic targets. The current review aims to provide a comprehensive overview of the current animal models used in mucositis research. Recent findings A wide variety of animal models of mucositis exist highlighting the highly heterogenous landscape of supportive oncology and the unique cytotoxic mechanisms of different anticancer agents. Golden Syrian hamsters remain the gold-standard species for investigation of oral mucositis induced by single dose and fractionated radiation as well as chemoradiation. There is no universally accepted gold-standard model for the study of gastrointestinal mucositis, with rats, mice, pigs and dogs all offering unique perspectives on its pathobiology. Summary Animal models are a critical aspect of mucositis research, providing unprecedent insight into the pathobiology of mucositis. Introduction of tumour-bearing models, cyclic dosing scheduled, concomitant agents and genetically modified animals have been integral in refining our understanding of mucositis.