Checkpoint inhibitor-associated bullous cutaneous immune-related adverse events: a multicentre observational study.

BACKGROUND: Checkpoint inhibitor (CPI) therapy has significantly improved overall survival in several cancers including metastatic melanoma (MM) and in the adjuvant setting. Cutaneous immune-related adverse events (irAEs) secondary to CPIs are commonly observed; however, autoimmune blistering disorders such as bullous pemphigoid (BP) are rare. OBJECTIVES: To review the prevalence, incidence risk, clinicopathological features and management of toxicity in bullous cutaneous irAEs associated with CPI therapy. METHODS: A multicentre, retrospective, observational study of CPI-associated bullous irAEs in adults with all cancers across four UK specialist centres between 2006 and 2019. RESULTS: In total, 7391 patients were identified. CPI-associated bullous irAEs including BP (n = 16) occurred in 0·3% (n = 22). The median age of onset was 76 years, and there was a male predominance. Most patients had cutaneous melanoma (73%, n = 16), of which 81% (13 of 16) were BRAF wildtype. Grade 1, 2, 3 and 4 skin toxicity occurred in 9%, 45%, 41% and 5%, respectively. The mucosae were involved in 27%, and 25% of confirmed cases of BP did not present with bullae. The median time to onset of bullous irAEs was 12 months, with a median total symptom duration of 6 months. Single PD-1/PD-L1 agents had a longer time to onset of symptoms than combination therapy (median 12 vs. 7 months, respectively). Overall, 91%, 64% and 9% of patients required one, two or three lines of treatment, respectively. Two cases occurred after completion of CPIs (1 and 3 months). Of the 20 cases that presented while on CPIs this was permanently discontinued in 55% (11 of 20) and temporarily held in 20% (four of 20). In the four held cases of CPI, bullous eruption reflared in 50%. CONCLUSIONS: CPI-associated bullous skin toxicity is a rare cutaneous irAE occurring in approximately 0·3% of cases over 13 years of treated patients in this series. Not all cases are diagnostic of BP, but management remains the same. There is a prolonged latency of onset compared with other cutaneous irAEs, with a median time of 12 months, and they can occur after cessation of therapy. Discontinuation of CPIs may be required. Recognizing bullous irAEs promptly and referral to dermatology are essential to optimize management and improve patient outcomes and tumour responses. What is already known about this topic? Checkpoint inhibitor (CPI)-associated bullous pemphigoid is a rare dermatological immune-related adverse event (irAE) that has been reported in small case series and reports. What does this study add? This is the largest multicentre, observational study conducted in the UK over the longest period of 13 years, which demonstrates an overall incidence of bullous cutaneous irAEs secondary to CPIs of 0·3%. Clinical presentation is variable, with one-quarter of patients with bullous pemphigoid presenting without bullae, and mucosal involvement was noted in 27%. Prolonged pruritus is frequently a prodromal symptom. The median time to diagnosis is 12 months and irAEs rarely present after cessation of treatment. Time to onset of symptoms is longer with a single CPI, but with a shorter duration of symptoms compared with combination CPI therapy. Most patients had cutaneous melanoma, of which 81% were BRAF wildtype.

A review of the role of stem cells in the development and treatment of glioma.

The neurosurgical management of patients with intrinsic glial cancers is one of the most rapidly evolving areas of practice. This has been fuelled by advances in surgical technique not only in cytoreduction but also in drug delivery. Further innovation will depend on a deeper understanding of the biology of the disease and an appreciation of the limitations of current knowledge. Here we review the controversial topic of cancer stem cells applied to glioma to provide neurosurgeons with a working overview. It is now recognised that the adult human brain contains regionally specified cell populations capable of self-renewal that may contribute to tumour growth and maintenance following accumulated mutational change. Tumour cells adapted to maintain growth demonstrate some stem-like characteristics and as such constitute a legitimate therapeutic target. Cellular reprogramming technologies raise the potential of developing stem cells as novel surgical tools to target disease and possibly ameliorate some of the consequences of treatment. Achieving these goals remains a significant challenge to neurosurgical oncologists, not least in challenging how we think about treating brain cancer. This review will briefly examine our understanding of adult stem cells within the brain, the evidence that they contribute to the development of brain tumours as tumour-initiating cells, and the potential implications for therapy. It will also look at the role stem cells may play in the future management of glioma.

A non-hierarchical organization of tumorigenic NG2 cells in glioblastoma promoted by EGFR.

BACKGROUND: Expression of neuron-glial antigen 2 (NG2) identifies an aggressive malignant phenotype in glioblastoma (GBM). Mouse models have implicated NG2 in the genesis, evolution, and maintenance of glial cancers and have highlighted potential interactions between NG2 and epidermal growth factor receptor (EGFR). However, it is unknown whether the lineage relationship of NG2+ and NG2- cells follows a hierarchical or stochastic mode of growth. Furthermore, the interaction between NG2 and EGFR signaling in human GBM is also unclear. METHODS: Single GBM NG2+ and NG2- cells were studied longitudinally to assess lineage relationships. Short hairpin RNA knockdown of NG2 was used to assess the mechanistic role of NG2 in human GBM cells. NG2+ and NG2- cells and NG2 knockdown (NG2-KD) and wild type (NG2-WT) cells were analyzed for differential effects on EGFR signaling. RESULTS: Expression of NG2 endows an aggressive phenotype both at single cell and population levels. Progeny derived from single GBM NG2- or GBM NG2+ cells consistently establish phenotypic equilibrium, indicating the absence of a cellular hierarchy. NG2 knockdown reduces proliferation, and mice grafted with NG2-KD survive longer than controls. Finally, NG2 promotes EGFR signaling and is associated with EGFR expression. CONCLUSIONS: These data support a dynamic evolution in which a bidirectional relationship exists between GBM NG2+ and GBM NG2- cells. Such findings have implications for understanding phenotypic heterogeneity, the emergence of resistant disease, and developing novel therapeutics.

Characteristics and outcome of patients with DNACPR orders in an acute hospital; an observational study.

AIMS: To establish the characteristics and outcomes of patients with Do Not Attempt Cardiopulmonary Resuscitation (DNACPR) orders; to assess whether particular patient characteristics are associated with discussing resuscitation orders with patients. METHODS: Retrospective case note analysis from an acute hospital in 2009 was performed on: all in-hospital deaths; all patients who had carbon-copies of their DNACPR forms returned to the resuscitation department and a sample of age-matched discharged patients without known DNACPR order forms. Univariate and multivariate logistic regression analysis was used to test the significance of the associations and calculate odds ratios. RESULTS: Of 541 sampled patients, 51% of patients with DNACPR orders were discharged. Baseline characteristics of those who had in-hospital deaths or were discharged with DNACPR orders were similar. The overall one-year mortality for patients with a DNACPR order was 83%. 50% of patients had documentation of having DNACPR orders discussed: this was consistent across patient characteristics including those who were discharged and those who had in-hospital deaths. Cases of "inappropriate" resuscitation attempts were identified. CONCLUSIONS: About half of patients with DNACPR orders were discharged home, and 17% were alive at one year. Characteristics of patients and frequency of discussions were similar in those who died or were discharged. Current focus of use of DNACPR orders only on those identified as most likely to die makes inappropriate resuscitation attempt a likely occurrence, and care is required to ensure conflation with "end of life" pathways does not distort the treatments given to this vulnerable group.

Enhanced stability and activity of temozolomide in primary glioblastoma multiforme cells with cucurbit[n]uril.

Temozolomide (TMZ) is the primary chemotherapeutic agent for treatment of glioblastoma multiforme (GBM) yet it has a fast rate of degradation under physiological conditions to the 'active' MTIC, which has poor penetration of the blood-brain barrier and cellular absorption. Herein we have demonstrated binding of TMZ within the cavity of nano-container cucurbit[7]uril, resulting in a decreased rate of drug degradation. Prolonging the lifetime of the TMZ under physiological conditions through encapsulation dramatically improved the drug's activity against primary GBM cell lines as more TMZ could be absorbed by the cells before degradation. This work can potentially lead to increases in the drug's propensity for crossing the blood-brain barrier and absorption into the GBM cells, thereby increasing the efficacy of this chemotherapy.