Human Studies

Tumor-related cancer pain often comprises mixed pain with both nociceptive and neuropathic components. Whether tumor-related cancer pain includes a neuropathic component impacts the therapeutic strategy. The aim of this cross-sectional study was to investigate the usefulness of two screening tools for neuropathic pain, painDETECT and Self-Report Leeds Assessment of Neuropathic Symptoms and Signs (S-LANSS), in identifying the neuropathic component of mixed pain among patients with tumor-related cancer pain.

Relief of cancer-related pain remains challenging despite the availability of a range of opioid and non-opioid medications. Animal models demonstrate that T lymphocytes may mediate analgesia by producing endogenous opioids, but definitive clinical data are limited. Adoptive transfer of ex vivo activated T cell products (ACT) is being tested as an anti-cancer therapy. We retrospectively reviewed the medical charts of 357 patients with various malignancies who received three intravenous infusions of autologous cytokine-activated T cell-enriched products. Among these were fifty-five (55) patients who required opioids for moderate or severe cancer-related pain. Opioid dosage and cancer pain score were recorded daily for 2 consecutive weeks prior to and 2 weeks after the ACT infusions. The average oral morphine equivalent doses (OMED) and cancer pain scores were significantly decreased following the ACT infusions. The proportion of patients with breakthrough pain also declined. Moreover, higher frequencies of expanded CD3+, CD3+/CD4+, and CD3+/CD8+ T cells within the ACT product were associated with favorable analgesic effects. Transient elevations in CD3+ and CD3+/CD8+ T cell subpopulations and decreases in CD4CD25 Treg were observed in patients' blood after the ACT. In conclusion, ACT was capable of reducing cancer pain severity and opioid consumption and favorably modulating peripheral blood T cell populations.

Cohort/psychometric study OBJECTIVES: The primary objective was to determine the psychometric properties and the utility of the Neuropathic Pain Symptom Inventory (NPSI) in subgrouping people with moderate to severe neuropathic pain after spinal cord injury (SCI).

Pain is the primary symptom of chronic pancreatitis (CP), but methods for sensory testing and pain characterization have not previously been validated for clinical use. We present a clinically feasible method for the assessment and characterization of pain mechanisms in patients with CP based on quantitative sensory testing (QST).

The trigeminal nerve (TGN) is the largest cranial nerve and can be involved in multiple inflammatory, compressive, ischemic or other pathologies. Currently, imaging-based approaches to identify the TGN mostly rely on T2-weighted magnetic resonance imaging (MRI), which provides localization of the cisternal portion of the TGN where the contrast between nerve and cerebrospinal fluid (CSF) is high enough to allow differentiation. The course of the TGN within the brainstem as well as anterior to the cisternal portion, however, is more difficult to display on traditional imaging sequences. An advanced imaging technique, diffusion MRI (dMRI), enables tracking of the trajectory of TGN fibers and has the potential to visualize anatomical regions of the TGN not seen on T2-weighted imaging. This may allow a more comprehensive assessment of the nerve in the context of pathology. To date, most work in TGN tracking has used clinical dMRI acquisitions with a b-value of 1000 s/mm and conventional diffusion tensor MRI (DTI) tractography methods. Though higher b-value acquisitions and multi-tensor tractography methods are known to be beneficial for tracking brain white matter fiber tracts, there have been no studies conducted to evaluate the performance of these advanced approaches on nerve tracking of the TGN, in particular on tracking different anatomical regions of the TGN.