Pathophysiologic implications of elevated prevalence of hereditary alpha-tryptasemia in all mastocytosis subtypes.

BACKGROUND: Mastocytosis and monoclonal mast cell (MC) activation syndrome (MMAS) are heterogeneous conditions characterized by the accumulation of atypical MCs. Despite the recurrent involvement of KIT mutations, the pathophysiologic origin of mastocytosis and MMAS is unclear. Although hereditary α-tryptasemia (HαT, related to TPSAB1 gene duplication) is abnormally frequent in these diseases, it is not known whether the association is coincidental or causal. OBJECTIVE: We evaluated the prevalence of HαT in all mastocytosis subtypes and MMAS and assessed the pathophysiologic association with HαT. METHODS: Clinical data, laboratory data, KIT mutations, TPSAB1 duplication (assessed by droplet digital PCR), and HαT prevalence were retrospectively recorded for all patients with mastocytosis and MMAS registered in the French national referral center database and compared to a control cohort. To increase the power of our analysis for advanced systemic mastocytosis (advSM), we pooled our cohort with literature cases. RESULTS: We included 583 patients (27 with MMAS and 556 with mastocytosis). The prevalence of HαT in mastocytosis was 12.6%, significantly higher than in the general population (5.7%, P = .002) and lower than in MMAS (33.3%, P = .02). HαT+ patients were more likely to have anaphylactic reactions and less likely to have cutaneous lesions than HαT- patients (43.0% vs 24.4%, P = .006; 57.7% vs 75.6%, respectively, P = .006). In the pooled analysis, the prevalence of HαT was higher in advSM (11.5%) than in control cohorts (5.2%, P = .01). CONCLUSION: Here we confirm the increase incidence of anaphylaxis in HαT+ mastocytosis patients. The increased prevalence of HαT in all subtypes of systemic mastocytosis (including advSM) is suggestive of pathophysiologic involvement.

Characteristics and outcomes associated with CD2 and CD25 expression on bone marrow mast cells in patients with systemic mastocytosis.

Not available.

Histological characterization of liver involvement in systemic mastocytosis.

BACKGROUND AND AIMS: Systemic mastocytosis (SM) is characterized by the accumulation of atypical mast cells (MCs) in organs. Liver histology of SM has been marginally described and accurate histological classification is critical, given the consequences of aggressive SM diagnosis. We aimed to describe the histological features associated with liver SM using updated tools. METHODS: Using the database of the French Reference Centre for Mastocytosis, we retrospectively identified patients with a liver biopsy (LB) and a diagnosis of SM. All LB procedures were performed according to the local physician in charge and centrally reviewed by an expert pathologist. RESULTS: A total of 28 patients were included: 6 had indolent SM, 9 had aggressive SM, and 13 had SM with an associated hematologic neoplasm. Twenty-five (89%) patients presented hepatomegaly, and 19 (68%) had portal hypertension. The LB frequently showed slight sinusoid dilatation (82%). Fibrosis was observed in 3/6 indolent SM and in almost all advanced SM cases (21/22), but none of them showed cirrhosis. A high MC burden (>50 MCs/high-power field) was correlated with elevated blood alkaline phosphatase levels (p = .030). The presence of portal hypertension was associated with a higher mean fibrosis grade (1.6 vs. 0.8 in its absence; p = .026). In advanced SM, the presence of nodular regenerative hyperplasia (NRH) was associated with decreased overall survival (9.5 vs. 46.3 months, p = .002). CONCLUSIONS: MC infiltration induced polymorphic hepatic lesions and the degree of fibrosis is associated with portal hypertension. NRH identifies a poor prognosis subgroup of patients with advanced SM. Assessing liver histology can aid in SM prognostic evaluation.

Comparison of prognostic scores according to WHO classification in 170 patients with advanced mastocytosis and C-finding treated with midostaurin.

Advanced systemic mastocytosis (AdvSM) encompasses heterogeneous mastocytosis subtypes and is associated with poor outcomes. Although midostaurin was the first tyrosine kinase inhibitor to be approved for AdvSM patients, long-lasting responses are limited. The mutation-Adjusted Risk Score (MARS), the International Prognostic Scoring System for mastocytosis (IPSM) and the Global Prognostic Score for Systemic Mastocytosis (GPSM) have been established to characterize the outcomes of patients with overall AdvSM. However, given the outcome's dependency on the AdvSM subtype, prognostic characterization within each subtype is critical. We aimed to study the predictive ability using Harrell's concordance index of prognostic scores according to the AdvSM subtype. We conducted a nationwide retrospective study using the French mastocytosis reference center's registry and included all midostaurin-treated patients with C finding. Overall, 170 patients were identified: 46 aggressive SM (ASM), 11 mast cell leukemia (MCL), and 113 SM with associated hematological neoplasm (SM-AHN). All risk scores improved their discriminative value for overall survival (OS) when combined with the AdvSM subtype. The best predictive value was for adjusted MARS (C-index = 0.689), followed by GPSM (C-index = 0.677) and IPSM (C-index = 0.618). In a multivariable analysis, MARS stratification and the AdvSM subtype were both prognostic for OS. Accordingly, five subgroups of patients with AdvSM and a different median OS were identified: 9.9 months for MCL, 24 months for intermediate/high-risk SM-AHN, 33 months for intermediate/high-risk ASM, 58 months for low-risk SM-AHN and was not reached for low-risk ASM (p < 0.001). The AdvSM subtype and the MARS are the most predictive of OS and should prompt specific management.

Treatment of familial glomangiomatosis with Nd:YAG laser: a case report.

Familial glomangiomatosis is a rare autosomal dominant vascular malformation caused by a mutation in the glomulin GLMN gene. It is characterized by the appearance of multiple glomus tumors composed of dysmature veins surrounded by glomus cells. We present a case of an 11-year-old girl with familial glomangiomatosis successfully treated with Nd:YAG long-pulse laser. Three sessions of laser treatment were performed, resulting in more than 80% reduction of the lesion and complete disappearance of pain, with no adverse effects reported. This case report demonstrates the excellent risk-benefit ratio of Nd:YAG long-pulse laser in the treatment of familial glomangiomatosis.

Omalizumab in the treatment of adult patients with mastocytosis: A systematic review.

BACKGROUND: Mastocytosis is associated with mast cell (MC) mediator-related symptoms for which limited therapies are available. OBJECTIVE: Our aim was to assess the efficacy and safety of omalizumab in the treatment of MC mediator-related symptoms in adult patients with mastocytosis. RESULTS: We identified one multi-centre retrospective cohort study (39 patients), one retrospective cohort study (13 patients), 4 case series and 10 case reports. No published controlled randomized study was identified. We included 69 patients (13 patients with cutaneous mastocytosis and 56 with systemic mastocytosis). The mean age was 48 years. Omalizumab maintenance dose was 300 mg for the majority of patients. The mean duration of treatment was 17 months. Treatment led to a tolerability of venom immunotherapy and to a complete resolution of severe reactions in all patients with post-honeybee sting anaphylaxis. Complete resolution of idiopathic anaphylaxis episodes was noted in 84% of the patients. Complete resolution of palpitations, gastrointestinal, cutaneous, neuropsychiatric, respiratory and musculoskeletal symptoms was observed at a rate of 43%, 29%, 27%, 11%, 9% and 0%, respectively. Efficacy was maintained for the entire duration of the treatment in all but four responders. Adverse events were reported for 13 patients. CONCLUSIONS AND CLINICAL RELEVANCE: Omalizumab appears to prevent some life-threatening reactions associated with mastocytosis and may be a good option to treat the associated symptoms. However, the evidence relied upon is observational, uncontrolled and from a small number of patients. A randomized controlled trial is needed to better understand the place of omalizumab in mastocytosis treatment.

Hydroxychloroquine as a novel therapeutic approach in mast cell activation diseases.

There is no therapeutic agent approved in cutaneous mastocytosis and mast cell activation syndrome. We report the efficacy of hydroxychloroquine in four patients with cutaneous mastocytosis (n = 2) and mast cell activation syndrome (n = 2). We show that this molecule reduces the long-term survival of primary human mast cells, interferes with lysosome function and leads to the accumulation of non-functional tryptase in the mast cell granules. Furthermore, hydroxychloroquine decreases the production of pro-inflammatory mediators.

Masitinib for treatment of severely symptomatic indolent systemic mastocytosis: a randomised, placebo-controlled, phase 3 study.

BACKGROUND: Indolent systemic mastocytosis, including the subvariant of smouldering systemic mastocytosis, is a lifelong condition associated with reduced quality of life. Masitinib inhibits KIT and LYN kinases that are involved in indolent systemic mastocytosis pathogenesis. We aimed to assess safety and efficacy of masitinib versus placebo in severely symptomatic patients who were unresponsive to optimal symptomatic treatments. METHODS: In this randomised, double-blind, placebo-controlled, phase 3 study, we enrolled adults (aged 18-75 years) with indolent or smouldering systemic mastocytosis, according to WHO classification or documented mastocytosis based on histological criteria, at 50 centres in 15 countries. We excluded patients with cutaneous or non-severe systemic mastocytosis after a protocol amendment. Patients were centrally randomised (1:1) to receive either oral masitinib (6 mg/kg per day over 24 weeks with possible extension) or matched placebo with minimisation according to severe symptoms. The primary endpoint was cumulative response (≥75% improvement from baseline within weeks 8-24) in at least one severe baseline symptom from the following: pruritus score of 9 or more, eight or more flushes per week, Hamilton Rating Scale for Depression of 19 or more, or Fatigue Impact Scale of 75 or more. We assessed treatment effect using repeated measures methodology for rare diseases via the generalised estimating equation model in a modified intention-to-treat population, including all participants assigned to treatment minus those who withdrew due to a non-treatment-related cause. We assessed safety in all patients who received at least one dose of study drug. This trial is registered with ClinicalTrials.gov, number NCT00814073. FINDINGS: Between Feb 19, 2009, and July 15, 2015, 135 patients were randomly assigned to masitinib (n=71) or placebo (n=64). By 24 weeks, masitinib was associated with a cumulative response of 18·7% in the primary endpoint (122·6 responses of 656·5 possible responses [weighted generalised estimating equation]) compared with 7·4% for placebo (48·9 of 656·5; difference 11·3%; odds ratio 3·6; 95% CI 1·2-10·8; p=0·0076). Frequent severe adverse events (>4% difference from placebo) were diarrhoea (eight [11%] of 70 in the masitinib group vs one [2%] of 63 in the placebo group), rash (four [6%] vs none), and asthenia (four [6%] vs one [2%]). The most frequent serious adverse events were diarrhoea (three patients [4%] vs one [2%]) and urticaria (two [3%] vs none), and no life-threatening toxicities occurred. One patient in the placebo group died (unrelated to study treatment). INTERPRETATION: These study findings indicate that masitinib is an effective and well tolerated agent for the treatment of severely symptomatic indolent or smouldering systemic mastocytosis. FUNDING: AB Science (Paris, France).

Extracorporeal Photopheresis: An Efficacious and Well-Tolerated Treatment for Cutaneous and Oral Mucosal Chronic Graft-versus-Host Disease.

BACKGROUND: Extracorporeal photopheresis (ECP) is a second-line therapy for steroid-refractory chronic graft-versus-host disease (cGVHD). OBJECTIVE: We describe the long-term efficacy and tolerability of ECP according to the cutaneous phenotype of cGVHD and report on the reduced need for immunosuppressant drugs in this setting. PATIENTS AND METHODS: Fourteen patients (8 females) with cutaneous and/or mucosal cGVHD, treated with ECP between October 2010 and May 2016 within a single center, were included. Final analyses included patients who had received ECP for at least 12 months. We prospectively evaluated the efficacy of ECP using lesion-specific clinical scores and by recording changed doses of systemic immunosuppressants. RESULTS: Of the 14 patients, sclerotic skin lesions were present in 10 (71%). The mRODNAN score decreased in all patients from month 9 onwards, with 40 and 77% reductions at 12 and 36 months, respectively. Six patients (43%) presented with cutaneous lichenoid lesions: this score was reduced in all patients by month 3, reaching a 93% reduction by month 12. Five patients (36%) experienced oral mucosal lichenoid lesions: these scores were decreased by 55% at month 12 and by 100% by month 33. The use of systemic immunosuppressants was reduced in all patients; 4 patients could stop all immunosuppressant drugs after 2 years. ECP was stopped in 3 patients after a complete response. No major ECP-associated adverse effects were observed. DISCUSSION AND CONCLUSION: ECP was an effective long-term therapy for oral and cutaneous cGVHD: consequently, dose levels of therapeutic immunosuppression could be reduced.

Telangiectasia macularis eruptiva perstans (TMEP): A form of cutaneous mastocytosis with potential systemic involvement.

BACKGROUND: Telangiectasia macularis eruptiva perstans (TMEP) has not been fully characterized. OBJECTIVE: We sought to estimate the frequency and clinical characteristics of TMEP in a cohort of adult patients with cutaneous mastocytosis, and to assess the presence of systemic involvement. METHODS: We included all consecutive patients evaluated for cutaneous mastocytosis in 2 centers: the Mastocytosis Competence Center of the Midi-Pyrénées from May 2006 to December 2013, and the French Reference Center for Mastocytosis from January 2008 to September 2013. Skin phenotype, histopathology, presence of KIT mutation in the skin, and assessment of systemic involvement according to World Health Organization (WHO) criteria were prospectively investigated. RESULTS: Of 243 patients with cutaneous mastocytosis, 34 (14%) were given a diagnosis of TMEP. The diagnosis of systemic mastocytosis was established in 16 patients (47%) with TMEP. Three patients (9%) had aggressive systemic mastocytosis (C-findings according to WHO). In all, 32 patients (94%) exhibited at least 1 mast cell activation-related symptom. LIMITATIONS: Patient recruitment was undertaken at 2 referral centers with expertise in the diagnosis and treatment of mastocytosis so that the clinical findings and incidence of systemic involvement may be overestimated in comparison with the overall population of patients with TMEP. CONCLUSION: TMEP accounts for about 14% of patients with cutaneous mastocytosis. The disease manifests as mast cell activation symptoms in almost all patients and can be associated with systemic involvement in about 50% of cases.

Surgical Treatment of Facial Basal Cell Carcinoma: Patient-Based Assessment of Clinical Outcome in a Prospective Cohort Study.

BACKGROUND: There are limited data on the esthetic, functional, and morphological outcomes of surgical treatment of facial basal cell carcinoma (BCC). OBJECTIVE: The aim of our study was to assess the determinants of the evaluation of both the patients and the investigator of the esthetic, functional, and morphological impact of the surgical treatment of facial BCC. METHODS: A prospective observational study evaluated 111 patients treated surgically for facial BCCs (n = 135 BCCs), using the Patient and Observer Scar Assessment Scale (POSAS), a validated and reliable scale designed for the evaluation of all types of scars by professionals and patients. RESULTS: Scar assessment rated by the patients was very good. Skin aging was associated with a better surgical outcome as evaluated by POSAS (OR = 0.30, 95% CI: 0.09-0.98; p = 0.04). Conversely, histologically infiltrative or sclerosing BCC (OR = 2.33, 95% CI: 0.95-5.71; p = 0.06) was independently associated with poorer POSAS. In terms of the investigator's evaluation, aging signs (protective factor: OR = 0.17, 95% CI: 0.04-0.73; p = 0.01), location on the H-zone of the face (risk factor: OR = 2.95, 95% CI: 1.07-8.15; p = 0.03), and histologically infiltrative or sclerosing BCC (risk factor: OR = 2.89, 95% CI: 1.01-8.29; p = 0.04) were independently associated with POSAS. CONCLUSION: Esthetic, functional, and morphological outcomes of facial BCC surgery provide high patient satisfaction overall. Taking wider margins requires specific measures to improve the surgical outcome.

Photo-induced graft-versus-host disease.

Overlap chronic graft-versus-host disease (GVHD) associates both features of acute and chronic GVHD. Trigger factors for chronic GVHD are unclear. We describe two patients who received allogenic haematopoietic stem-cell transplantation, and who later developed overlap chronic GVHD after sun exposure. Available data from in vivo investigations suggest ultraviolet B radiation (UVB) has a beneficial effect on acute and chronic GVHD. The role of sun irradiation as a trigger for isomorphic cutaneous GVHD has been rarely reported in the literature. Herein, we demonstrate for the first time, using repetitive broadband phototesting, that UVB triggers chronic GVHD.

Avapritinib versus Placebo in Indolent Systemic Mastocytosis.

BACKGROUND: Indolent systemic mastocytosis (ISM) is a clonal mast-cell disease driven by the KIT D816V mutation. We assessed the efficacy and safety of avapritinib versus placebo, both with best supportive care, in patients with ISM. METHODS: We randomized patients with moderate to severe ISM (total symptom score [TSS] of ≥28; scores range from 0 to 110, with higher numbers indicating more severe symptoms) two to one to avapritinib 25 mg once daily (n=141) or placebo (n=71). The primary end point was mean change in TSS based on the 14-day average of patient-reported severity of 11 symptoms. Secondary end points included reductions in serum tryptase and blood KIT D816V variant allele fraction (≥50%), reductions in TSS (≥50% and ≥30%), reduction in bone marrow mast cells (≥50%), and quality of life measures. RESULTS: From baseline to week 24, avapritinib-treated patients had a decrease of 15.6 points (95% CI, −18.6 to −12.6) in TSS compared to a decrease of 9.2 points (−13.1 to −5.2) in the placebo group; P<0.003. From baseline to Week 24, 76/141 patients (54%; 45% to 62%) in the avapritinib group compared to 0/71 patients in the placebo group achieved a ≥50% reduction in serum tryptase level; P<0.001. Edema and increases in alkaline phosphatase were more common with avapritinib than placebo; there were few treatment discontinuations because of adverse events. CONCLUSIONS: In this trial, avapritinib was superior to placebo in reducing uncontrolled symptoms and mast-cell burden in patients with ISM. The long-term safety and efficacy of this approach for patients with ISM remain the focus of the ongoing trial. (Funded by Blueprint Medicines Corporation; ClinicalTrials.gov number, NCT03731260.)

Effectiveness and Safety of Adalimumab, Etanercept and Ustekinumab for Severe Psoriasis in Children Under 12 Years of Age: A French-Italian Daily Practice Cohort (BiPe Jr).

INTRODUCTION: Biological therapies are valuable treatments for severe psoriasis. Children aged under 12 years are underrepresented in therapeutic trials for these drugs. The objective of the 'BiPe Jr' cohort study was to evaluate the drug survival, effectiveness, tolerance and switching patterns of biological therapies in children under 12 years of age with psoriasis. METHODS: We conducted a multicentre retrospective study of children with psoriasis who received at least one injection of a biological agent, even off-licence, before the age of 12 years in France and Italy, collecting the data between April and August 2021. The data collected were from March 2012 up to August 2021. RESULTS: In total, 82 children (mean age: 9.1 years; females: 61.0%) received 106 treatments. The drugs administered were adalimumab (n = 49), etanercept (n = 37), ustekinumab (n = 15), anakinra (n = 2), infliximab (n = 2) and secukinumab (n = 1). The most common form of psoriasis was plaque psoriasis (62.9%). The Physician Global Assessment and the Psoriasis Area Severity Index (PASI) scores decreased significantly from baseline to 3 months after treatment initiation for the three main biological drugs; PASI went from 14.1 ± 9.4 to 4.1 ± 11.3 for adalimumab (p = 0.001), 14.9 ± 9.3 to 5.1 ± 4.0 for etanercept (p = 0.002) and 11.6 ± 8.3 to 2.6 ± 2.2 for ustekinumab (p = 0.007). A trend towards higher 2-year maintenance rates was observed for ustekinumab and adalimumab, compared with etanercept (p = 0.06). 52 children discontinued their biological therapy, most frequently due to inefficacy (n = 28) and remission (n = 14). Seven serious adverse events (SAEs) were reported, including four severe infections. DISCUSSION: Our analyses of drug survival and treatment patterns, combined with those of previous studies conducted in older children, indicate that there is a trend towards higher 2-year survival rates of ustekinumab and adalimumab. The SAEs identified were rare, but highlight the need for increased vigilance concerning infections. Overall, the biological therapies showed good effectiveness and safety profiles when used in daily practice for the treatment of young children with psoriasis.