Low risk of embryonic and other cancers in PIK3CA-related overgrowth spectrum: Impact on screening recommendations.

The PIK3CA-related overgrowth spectrum (PROS) encompasses various conditions caused by mosaic activating PIK3CA variants. PIK3CA somatic variants are also involved in various cancer types. Some generalized overgrowth syndromes are associated with an increased risk of Wilms tumor (WT). In PROS, abdominal ultrasound surveillance has been advocated to detect WT. We aimed to determine the risk of embryonic and other types of tumors in patients with PROS in order to evaluate surveillance relevance. We searched the clinical charts from 267 PROS patients for the diagnosis of cancer, and reviewed the medical literature for the risk of cancer. In our cohort, six patients developed a cancer (2.2%), and Kaplan Meier analyses estimated cumulative probabilities of cancer occurrence at 45 years of age was 5.6% (95% CI = 1.35%-21.8%). The presence of the PIK3CA variant was only confirmed in two out of four tumor samples. In the literature and our cohort, six cases of Wilms tumor/nephrogenic rests (0.12%) and four cases of other cancers have been reported out of 483 proven PIK3CA patients, in particular the p.(His1047Leu/Arg) variant. The risk of WT in PROS being lower than 5%, this is insufficient evidence to recommend routine abdominal imaging. Long-term follow-up studies are needed to evaluate the risk of other cancer types, as well as the relationship with the extent of tissue mosaicism and the presence or not of the variant in the tumor samples.

First report of a short in-frame biallelic deletion removing part of the EGF-like domain calcium-binding motif in LTBP4 and causing autosomal recessive cutis laxa type 1C.

Cutis laxa (CL) is a rare connective tissue disorder characterized by wrinkled, abundant and sagging skin, sometimes associated with systemic impairment. Biallelic alterations in latent transforming growth factor beta-binding protein 4 gene (LTBP4) cause autosomal recessive type 1C cutis laxa (ARCL1C, MIM #613177). The present report describes the case of a 17-months-old girl with cutis laxa together with a literature review of previous ARCL1C cases. Based on proband main clinical signs (cutis laxa and pulmonary emphysema), clinical exome sequencing (CES) was performed and showed a new nine base-pairs homozygous in-frame deletion in LTBP4 gene. RT-PCR and cDNA Sanger sequencing were performed in order to clarify its impact on RNA. This report demonstrates that a genetic alteration in the EGF-like 14 domain calcium-binding motif of LTBP4 gene is likely responsible for cutis laxa in our patient.

Formation of keto-type ceramides in palmoplantar keratoderma based on biallelic KDSR mutations in patients.

Functional skin barrier requires sphingolipid homeostasis; 3-ketodihydrosphingosine reductase or KDSR is a key enzyme of sphingolipid anabolism catalyzing the reduction of 3-ketodihydrosphingosine to sphinganine. Biallelic mutations in the KDSR gene may cause erythrokeratoderma variabilis et progressive-4, later specified as PERIOPTER syndrome, emphasizing a characteristic periorifical and ptychotropic erythrokeratoderma. We report another patient with compound heterozygous mutations in KDSR, born with generalized harlequin ichthyosis, which progressed into palmoplantar keratoderma. To determine whether patient-associated KDSR mutations lead to KDSR substrate accumulation and/or unrecognized sphingolipid downstream products in stratum corneum (SC), we analyzed lipids of this and previously published patients with non-identical biallelic mutations in KDSR. In SC of both patients, we identified 'hitherto' unobserved skin ceramides with an unusual keto-type sphingoid base in lesional and non-lesional areas, which accounted for up to 10% of the measured ceramide species. Furthermore, an overall shorter mean chain length of free and bound sphingoid bases was observed-shorter mean chain length of free sphingoid bases was also observed in lesional psoriasis vulgaris SC, but not generally in lesional atopic dermatitis SC. Formation of keto-type ceramides is probably due to a bottle neck in metabolic flux through KDSR and a bypass by ceramide synthases, which highlights the importance of tight intermediate regulation during sphingolipid anabolism and reveals substrate deprivation as potential therapy.

Sirolimus (Rapamycin) for Slow-Flow Malformations in Children: The Observational-Phase Randomized Clinical PERFORMUS Trial.

IMPORTANCE: Sirolimus is increasingly being used to treat various vascular anomalies, although evidence of its efficacy is lacking. OBJECTIVE: To assess the efficacy and safety of sirolimus for children with slow-flow vascular malformations to better delineate the indications for treatment. DESIGN, SETTING AND PARTICIPANTS: This multicenter, open-label, observational-phase randomized clinical trial included 59 children aged 6 to 18 years with a slow-flow vascular malformation who were recruited between September 28, 2015, and March 22, 2018, in 11 French tertiary hospital centers. Statistical analysis was performed on an intent-to-treat basis from December 4, 2019, to November 10, 2020. INTERVENTIONS: Patients underwent an observational period, then switched to an interventional period when they received oral sirolimus (target serum levels, 4-12 ng/mL). The switch time was randomized from month 4 to month 8, and the whole study period lasted 12 months for each patient. MAIN OUTCOMES AND MEASURES: The primary outcome was change in the volume of vascular malformations detected on magnetic resonance imaging scan (with centralized interpretation) per unit of time (ie, between the interventional period and the observational period). Secondary outcomes included subjective end points: pain, bleeding, oozing, quality of life, and safety. RESULTS: Among the participants (35 girls [59.3%]; mean [SD] age, 11.6 [3.8] years), 22 (37.3%) had a pure venous malformation, 18 (30.5%) had a cystic lymphatic malformation, and 19 (32.2%) had a combined malformation, including syndromic forms. Variations in the volume of vascular malformations detected on magnetic resonance imaging scans associated with the duration period were not overall significantly different between the interventional period and the observational period (all vascular malformations: mean [SD] difference, -0.001 [0.007]; venous malformations: mean [SD] difference, 0.001 [0.004]; combined malformations: mean [SD] difference, 0.001 [0.009]). However, a significant decrease in volume was observed for children with pure lymphatic malformations (mean [SD] difference, -0.005 [0.005]). Overall, sirolimus had positive effects on pain, especially for combined malformations, and on bleeding, oozing, self-assessed efficacy, and quality of life. During sirolimus treatment, 56 patients experienced 231 adverse events (5 serious adverse events, none life-threatening). The most frequent adverse event was an oral ulcer (29 patients [49.2%]). CONCLUSIONS AND RELEVANCE: This observational-phase randomized clinical trial allows for clarifying the goals of patients and families when starting sirolimus therapy for children older than 6 years. Pure lymphatic malformations seem to be the best indication for sirolimus therapy because evidence of decreasing lymphatic malformation volume per unit of time, oozing, and bleeding and increasing quality of life was found. In combined malformations, sirolimus significantly reduced pain, oozing, and bleeding. Benefits seemed lower for pure venous malformations than for the 2 other subgroups, also based on symptoms. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02509468; clinicaltrialsregister.eu Identifier: 2015-001096-43.

[Use of the multiparametric panel CD3/CD4/CD8/CD7/CD26/CD158k in the detection and use of flow cytometry of Sezary cells]. / Apport du panel multiparamétrique CD3 CD4 CD8 CD7 CD26 CD158k dans la détection et le suivi par cytométrie en flux des cellules de Sézary.

The Sezary syndrome has been defined by a triad combining erythrodermia, generalized lymphadenopathy, and the presence of circulating Sezary cells > 1 × 109/L characterized by a CD4+/CD8- phenotype with loss of one or more T antigens (mainly CD7 and/or CD26). We retrospectively reviewed the immunophenotypic profiles of 10 SS patients followed in our institution (University Hospital at Nancy, France). The application of the WHO criteria resulted in a diagnostic confirmation for 9 out of 10 cases. Since 2008, new diagnostic and staging criteria have been proposed, including the CD158k/KIR3DL2 receptor detection. The application of these new criteria to our cohort led us to notice a phenotypic heterogeneity of our cases but allowed to achieve a relevant diagnosis of Sezary syndrome in all cases, especially for patients with lymphopenia. The use of such a panel of monoclonal antibodies also optimized the follow-up of the patients.

Clinical and neuroimaging findings in 33 patients with MCAP syndrome: A survey to evaluate relevant endpoints for future clinical trials.

Megalencephaly-CApillary malformation-Polymicrogyria (MCAP) syndrome results from somatic mosaic gain-of-function variants in PIK3CA. Main features are macrocephaly, somatic overgrowth, cutaneous vascular malformations, connective tissue dysplasia, neurodevelopmental delay, and brain anomalies. The objectives of this study were to describe the clinical and radiological features of MCAP, to suggest relevant clinical endpoints applicable in future trials of targeted drug therapy. Based on a French collaboration, we collected clinical features of 33 patients (21 females, 12 males, median age of 9.9 years) with MCAP carrying mosaic PIK3CA pathogenic variants. MRI images were reviewed for 21 patients. The main clinical features reported were macrocephaly at birth (20/31), postnatal macrocephaly (31/32), body/facial asymmetry (21/33), cutaneous capillary malformations (naevus flammeus 28/33, cutis marmorata 17/33). Intellectual disability was present in 15 patients. Among the MRI images reviewed, the neuroimaging findings were megalencephaly (20/21), thickening of corpus callosum (16/21), Chiari malformation (12/21), ventriculomegaly/hydrocephaly (10/21), cerebral asymmetry (6/21) and polymicrogyria (2/21). This study confirms the main known clinical features that defines MCAP syndrome. Taking into account the phenotypic heterogeneity in MCAP patients, in the context of emerging clinical trials, we suggest that patients should be evaluated based on the main neurocognitive expression on each patient.

Clinical and Therapeutic Aspects of Linear Psoriasis: A Study of 30 Cases.

BACKGROUND: Psoriasis affects 2-4% of the population, with the most common clinical type being plaque psoriasis. The linear form of psoriasis is very rare. The literature on linear psoriasis (LP) consists of only case reports, and data are few. OBJECTIVE: This study aimed to better understand LP in a large-scale study. PATIENTS AND METHODS: We retrospectively retrieved the medical records from 14 French medical centers of patients newly diagnosed clinically with LP, with or without the support of histology, between 1 February and 31 July 2015. For each case, we assessed the clinical features, treatments and treatment efficacy. RESULTS: In total, 30 cases of LP (mean age 26.8 years, 13 males) were reported. Mean age at onset of LP was 20.0 years, with 18 developing LP in childhood. Ten patients had a family history of psoriasis, and two had psoriatic arthritis. A total of 19 cases were linear at onset, with concomitant classical psoriasis; these were termed "superimposed" LP. The remaining 11 cases were not associated with classical psoriasis and were termed "isolated" LP. In four of the superimposed cases, LP developed when the patient was receiving systemic treatment: methotrexate (n = 2), etanercept (n = 1) or infliximab (n = 1). Topical steroids were effective in 76% of cases in which they were used, and systemic treatment was effective in < 66%. Treatments were less effective in LP than in classical psoriasis. DISCUSSION: We identified a wide range of LP, with two profiles: isolated LP and superimposed LP. Topical treatment usually evoked clinical response, with relative resistance to systemic therapy. Methotrexate and anti-tumor necrosis factor (TNF)-α therapies can possibly unmask LP.

Molecular diagnosis of PIK3CA-related overgrowth spectrum (PROS) in 162 patients and recommendations for genetic testing.

PURPOSE: Postzygotic activating mutations of PIK3CA cause a wide range of mosaic disorders collectively referred to as PIK3CA-related overgrowth spectrum (PROS). We describe the diagnostic yield and characteristics of PIK3CA sequencing in PROS. METHODS: We performed ultradeep next-generation sequencing (NGS) of PIK3CA in various tissues from 162 patients referred to our clinical laboratory and assessed diagnostic yield by phenotype and tissue tested. RESULTS: We identified disease-causing mutations in 66.7% (108/162) of patients, with mutant allele levels as low as 1%. The diagnostic rate was higher (74%) in syndromic than in isolated cases (35.5%; P = 9.03 × 10-5). We identified 40 different mutations and found strong oncogenic mutations more frequently in patients without brain overgrowth (50.6%) than in those with brain overgrowth (15.2%; P = 0.00055). Mutant allele levels were higher in skin and overgrown tissues than in blood and buccal samples (P = 3.9 × 10-25), regardless of the phenotype. CONCLUSION: Our data demonstrate the value of ultradeep NGS for molecular diagnosis of PROS, highlight its substantial allelic heterogeneity, and confirm that optimal diagnosis requires fresh skin or surgical samples from affected regions. Our findings may be of value in guiding future recommendations for genetic testing in PROS and other mosaic conditions.Genet Med advance online publication 02 February 2017.

Skin Biopsy in Netherton Syndrome: A Histological Review of a Large Series and New Findings.

Netherton syndrome (NS) is a severe genetic skin disorder, with often delayed or misleading clinical signs. The histological features of skin biopsies, usually described as a psoriasiform hyperplasia, have only been reported in isolated case reports or small case series. The aim of this study is to define, for the first time, the precise histological pattern of cutaneous lesions, in a large cohort of skin biopsies from confirmed NS patients. The study included 80 consecutive skin biopsies from 67 patients taken between January 1995 and June 2014. All were from confirmed NS patients with either a negative lympho-epithelial Kazal-type-related inhibitor (LEKTI) immunohistochemistry and/or molecular confirmation by identified mutation in SPINK5. In this cohort, the most frequent histological finding was also psoriasiform hyperplasia, but there were additional, less common, or previously unreported findings, including compact parakeratosis with large nuclei, subcorneum or intracorneum splitting, presence of clear cells in the upper epidermis or stratum corneum, dyskeratosis, dermal infiltrate with neutrophils and/or eosinophils, and dilated blood vessels in the superficial dermis. An early confirmation of the diagnosis of NS is essential for improved patient management. Thus, in the situation of a patient with an unknown skin disorder and non specific clinical presentation, the dermatopathologist may now be able to suggest the diagnosis of NS based on these newly reported characteristics. However, LEKTI immunohistochemistry remains the essential diagnostic investigation in cases with misleading or nonspecific histological features and is mandatory for the definitive diagnosis of NS in all patients.