Dermatomyositis unleashed by immune checkpoint inhibitors. Three additional cases and a review of the literature.

OBJECTIVES: Immune checkpoint inhibitors (ICI) have revolutionized the treatment of several locally advanced and metastatic tumors. They enhance the effector function of the immune system, consequently leading to different immune-related adverse events. The aim of the present study was to describe three cases of dermatomyositis (DM) triggered by ICI diagnosed at our institution and to perform a review of the literature. METHODS: We performed a retrospective clinical, laboratory, and pathological evaluation of three cases of DM triggered by ICI belonging to a cohort of 187 DM patients from the Clinic Hospital Muscle Research Group of Barcelona from January 2009 to July 2022. Moreover, we undertook a narrative review of the literature from January 1990 to June 2022. RESULTS: Cases from our institution were triggered by avelumab, an anti-PD-1 ligand (PD-L1), nivolumab, and pembrolizumab, both anti-programmed death-1 (PD-1). One of these patients had locally advanced melanoma, and two had urothelial carcinoma. The severity and response to treatment were heterogeneous among the different cases. All were positive at high titers for anti-TIF1γ autoantibodies; in one of them, serum before the onset of ICI was available, and anti-TIF1γ autoantibodies were already present. RNA expression of IFNB1, IFNG and genes stimulated by these cytokines were markedly elevated in these patients. CONCLUSIONS: In conclusion, data from our patients and the narrative review suggest that early positivity to anti-TIF1γ unleashed by ICI may play a role in the development of full-blown DM, at least in some cases.

Neuropathy and Muscle Cramps in Autologous and Allogeneic Hematopoietic Cell Transplantation Survivors.

Although autologous and allogeneic hematopoietic cell transplantation are used to treat hematologic diseases, they are associated with high morbidity and mortality. The goal of this cross-sectional study was to describe the incidence, characteristics, severity and clinical correlates of neuropathy and muscle cramps, as self-reported by hematopoietic cell transplantation survivors. We included all respondents to a survey conducted July 1, 2020, to June 30, 2021. Surveys were completed online or on-paper according to participants' preferences; they received one reminder if no survey was received 1 month after distribution. Statistics are primarily descriptive comparing subgroups of patients. Of 4641 potentially eligible patients, 1745 responded and are included in the analysis. Participants (615 [35%] autologous, 1130 [65%] allogeneic) were a median age of 64.1 years (interquartile range [IQR] 55.2-70.8) and surveyed at a median of 11 years (IQR 4-21) after their most recent transplantation. Neuropathy symptoms were reported by 65% of autologous recipients, 66% of allogeneic transplant recipients with current chronic graft versus host disease (GVHD), and 45% of allogeneic recipients who never developed chronic GVHD. Muscle cramps were reported by 56% of autologous recipients, and 52% of allogeneic recipients and were rated as "very painful" by nearly half of patients who experienced them. These results suggest that neuropathy symptoms and muscle cramps are much more prevalent among survivors after hematopoietic cell transplantation than previously recognized. Better approaches for prevention and treatment of these bothersome complications are needed.