Presence of Copy Number Variants Associated With Esotropia in Patients With Exotropia

Importance

Strabismus is a common ocular disorder of childhood. There is a clear genetic component to strabismus, but it is not known if esotropia and exotropia share genetic risk factors.

Objective

To determine whether genetic duplications associated with esotropia are also associated with exotropia.

Design, Setting, and Participants

This was a cross-sectional study conducted from November 2005 to December 2023. Individuals with constant or intermittent exotropia of any magnitude or a history of surgery for exotropia were recruited from pediatric ophthalmic practices. Data were analyzed from March to December 2023.

Exposure

Genetic duplication.

Main Outcomes and Measures

Presence of genetic duplications at 2p11.2, 4p15.2, and 10q11.22 assessed by digital droplet polymerase chain reaction. Orthoptic measurements and history of strabismus surgery were performed.

Results

A total of 234 individuals (mean [SD] age, 19.5 [19.0] years; 127 female [54.3%]) were included in this study. The chromosome 2 duplication was present in 1.7% of patients with exotropia (4 of 234; P = .40), a similar proportion to the 1.4% of patients with esotropia (23 of 1614) in whom it was previously reported and higher than the 0.1% of controls (4 of 3922) previously reported (difference, 1.6%; 95% CI, 0%-3.3%; P < .001). The chromosome 4 duplication was present in 3.0% of patients with exotropia (7 of 234; P = .10), a similar proportion to the 1.7% of patients with esotropia (27 of 1614) and higher than the 0.2% of controls (6 of 3922) in whom it was previously reported (difference, 2.8%; 95% CI, 0.6%-5.0%; P < .001). The chromosome 10 duplication was present in 6.0% of patients with exotropia (14 of 234; P = .08), a similar proportion to the 4% of patients with esotropia (64 of 1614) and higher than the 0.4% of controls (18 of 3922) in whom it was previously reported (difference, 5.6%; 95% CI, 2.5%-8.6%; P < .001). Individuals with a duplication had higher mean (SD) magnitude of deviation (31 [13] vs 22 [14] prism diopters [PD]; difference, 9 PD; 95% CI, 1-16 PD; P = .03), were more likely to have constant (vs intermittent) exotropia (70% vs 29%; difference, 41%; 95% CI, 20.8%-61.2%; P < .001), and had a higher rate of exotropia surgery than those without a duplication (58% vs 34%; difference, 24%; 95% CI, 3%-44%; P = .02).

Conclusions and Relevance

In this cross-sectional study, results suggest that the genetic duplications on chromosomes 2, 4, and 10 were risk factors for exotropia as well as esotropia. These findings support the possibility that esotropia and exotropia have shared genetic risk factors. Whether esotropia or exotropia develops in the presence of these duplications may be influenced by other shared or independent genetic variants or by environmental factors.

Diagnostic imaging of salivary gland cancers: REFCOR recommendations by the formal consensus method

OBJECTIVE

To define the indications for each imaging modality in the screening, characterization, extension and follow-up of salivary gland tumors.

MATERIAL AND METHODS

The French Network of Rare Head and Neck Tumors (REFCOR) formed a steering group who drafted a narrative review of the literature published on Medline and proposed recommendations. The level of adherence to the recommendations was then assessed by a rating group, according to the formal consensus method.

RESULTS

If a swelling of a salivary gland is palpable for 3 weeks, an ultrasound scan is recommended to confirm a tumoral lesion and rule out differential diagnoses. For a salivary gland tumor, MRI is recommended with diffusion-weighted and dynamic contrast-enhanced techniques. In the case of histologically proven malignancy or a highly suspicious lesion, a CT scan of the neck and chest is recommended to assess the tumor, lymph nodes and metastases. FDG-PET is not currently recommended in routine clinical practice for initial diagnosis, assessment of extension, evaluation of response to treatment, staging of recurrence, or follow-up of salivary gland tumors.

CONCLUSION

Assessing salivary tumors is based on MRI. Extension assessment is based on neck and chest CT.

Surgery of sublingual and minor salivary gland cancer: REFCOR recommendations by the formal consensus method

OBJECTIVE

To determine the indications and modalities for resection in the management of primary sublingual and minor salivary gland cancer, and the specific features of each primary location.

MATERIAL AND METHODS

The French Network of Rare Head and Neck Tumors (REFCOR) formed a steering group who drafted a narrative review of the literature published on Medline and proposed recommendations. The level of adherence to the recommendations was then assessed by a rating group, according to the formal consensus method.

RESULTS

Histological evidence (submucosal biopsy) is recommended before surgical treatment of minor salivary gland carcinoma. Surgical treatment is recommended, with optimal oncologic margins, adapted to anatomical factors, histologic type and grade and functional consequences, with reconstruction if necessary.

CONCLUSION

Treatment of primary minor salivary and sublingual gland cancer is surgical, with wide resection margins. The modalities of resection and reconstruction are highly dependent on tumor location, extension and histologic type.

Surgery of major salivary gland cancers: REFCOR recommendations by the formal consensus method

OBJECTIVE

To determine the role of surgery of the primary tumor site in the management of primary major salivary gland cancer.

MATERIAL AND METHODS

The French Network of Rare Head and Neck Tumors (REFCOR) formed a steering group, which drafted a non-systematic narrative review of the literature published on Medline, and proposed recommendations. The level of adherence to the recommendations was then assessed by a rating group, according to the formal consensus method.

RESULTS

Treatment of salivary gland tumor is mainly surgical. The gold standard for parotid cancer is a total parotidectomy, to obtain clear margins and remove all intraparotid lymph nodes. For low-grade tumors, partial parotidectomy with wide excision of the tumor is acceptable in the case of postoperative diagnosis on definitive histology. In the event of positive margins on definitive analysis, revision surgery should be assessed for feasibility, and performed if possible.

CONCLUSION

Treatment of primary major salivary gland cancer is based on surgery with clear resection margins, as far away as possible from the tumor. The type of surgery depends on tumor location, pathologic type and extension.

Lymph node surgery for salivary gland cancer: REFCOR recommendations by the formal consensus method

OBJECTIVE

To determine the indications for neck dissection in the management of parotid, submandibular or minor salivary gland cancers depending on the clinical situation: i.e., clinical lymph node involvement (cN+) or not (cN0); low or high risk of occult nodal metastasis; diagnosis of malignancy before, during or after surgery.

MATERIAL AND METHODS

The French Network of Rare Head and Neck Tumors (REFCOR) formed a steering group which drafted a narrative review of the literature published on Medline and proposed recommendations. The level of adherence to the recommendations was then assessed by a rating group according to the formal consensus method.

RESULTS

In cN+ salivary gland cancer, ipsilateral neck dissection is recommended. In cN0 salivary gland cancer, ipsilateral neck dissection is recommended, except for tumors at low risk of occult nodal metastasis. If definitive pathology reveals a high risk of occult nodal involvement, additional neck treatment is recommended: ipsilateral neck dissection or elective nodal irradiation.

CONCLUSION

The rate of occult lymph node involvement, and therefore the indication for elective neck dissection, depends primarily on the pathologic grade of the salivary gland cancer.

Post-treatment monitoring of salivary gland cancer: REFCOR recommendations by the formal consensus method

OBJECTIVE

To determine the frequency and modality of post-treatment monitoring of primary salivary gland cancer.

MATERIAL AND METHODS

The French Network of Rare Head and Neck Tumors (REFCOR) formed a steering group who drafted a narrative review of the literature published on Medline and proposed recommendations. The level of adherence to the recommendations was then assessed by a rating group, according to the formal consensus method.

RESULTS

Clinical monitoring should be adapted to the risk of recurrence: initially every 3 months and progressively spaced out, becoming annual after 5 years. Post-treatment head and neck and chest imaging is recommended at 3 months. Local and regional monitoring can then be carried out yearly or twice yearly with contrast-enhanced head and neck imaging. An annual chest CT scan is recommended for high-grade tumors. For lesions at high risk of late recurrence, very prolonged annual surveillance (up to 15 years) is recommended, including screening for pulmonary metastases.

CONCLUSION

Given the wide range of malignant salivary gland tumors, the modalities and frequency of post-treatment monitoring must be adapted to the expected course of the disease.

[Ethical considerations in ENT during the COVID-19 pandemic: Qualitative analysis of open-ended questions]

Introduction

La pandémie au coronavirus SARS-CoV-2 a profondément impacté la pratique des soignants. L’objectif est d’analyser les questionnements éthiques soulevés par la communauté ORL française pendant la première vague d’infections au COVID-19.

Méthodes

Un appel à témoignage a été lancé à propos des questionnements éthiques en ORL au mois d’avril 2020, avec quatre questions ouvertes standardisées : (i) les difficultés de prise en charge pour les patients COVID-19 positifs ; (ii) le retentissement de la crise sanitaire sur les patients COVID-19 négatifs ; (iii) la communication avec les équipes soignantes et/ou le personnel de consultation et de bloc ; et (iv) le traitement des informations par la presse et les instances nationales de l’ORL. Une analyse thématique de contenu a été effectuée en croisant avec les données épidémiologiques de chaque répondant.

Résultats

Trente et un réponses provenant de 13 départements français différents, dont 21 hospitaliers et 10 libéraux, âge médian de 45 ans et 17 hommes pour 14 femmes, ont été analysées. Les questionnements éthiques concernaient la prise en charge par les ORL des patients COVID-19 positifs, la modification des pratiques en consultation et au bloc opératoire, la crainte de perte de chance pour les patients COVID-19 négatifs, l’usage approprié des téléconsultations et du télétravail et les conséquences délétères des fausses informations pour le grand public.

Conclusion

En préparation de possibles futures pandémies, les aspects éthiques clés sont d’adapter la prise en charge des patients aux ressources et à la prévalence locale, et de diffuser des recommandations institutionnelles claires.

Tracheostomies after SARS-CoV-2 intubation, performed by academic otorhinolaryngologists in the Paris area of France: Preliminary results

Objective

To analyse tracheostomies after intubation for SARS-Cov-2 infection performed by otorhinolaryngologists in 7 university hospitals in the Paris area of France during the month March 24 to April 23, 2020.

Material and methods

A multicentre retrospective observational study included 59 consecutive patients. The main goals were to evaluate the number, characteristics and practical conditions of tracheostomies, and the COVID-19 status of the otorhinolaryngologists. Secondary goals were to analyse tracheostomy time, decannulation rate, immediate postoperative complications and laryngotracheal axis status.

Results

Tracheostomy indications were for ventilatory weaning and extubation failure in 86% and 14% of cases, respectively. The technique was surgical, percutaneous or hybrid in 91.5%, 3.4% and 5.1% of cases, respectively. None of the operators developed symptoms consistent with COVID-19. Postoperative complications occurred in 15% of cases, with no significant difference between surgical and percutaneous/hybrid techniques (P = 0.33), although no complications occurred after percutaneous or hybrid tracheostomies. No procedures or complications resulted in death. The decannulation rate was 74.5% with a mean tracheostomy time of 20 ± 12 days. In 55% of the patients evaluated by flexible endoscopy after decannulation, a laryngeal abnormality was found. On univariate analysis, no clinical features had a significant influence on tracheostomy time, decannulation rate or occurrence of laryngeal lesions.

Conclusion

The main findings of the present retrospective study were: absence of contamination of the surgeons, heterogeneity of practices between centres, a high rate of complications and laryngeal lesions whatever the technique, and the specificities of the patients.

Optic Nerve Head and Retinal Abnormalities Associated with Congenital Fibrosis of the Extraocular Muscles

Congenital fibrosis of the extraocular muscles (CFEOM) is a congenital cranial dysinnervation disorder caused by developmental abnormalities affecting cranial nerves/nuclei innervating the extraocular muscles. Autosomal dominant CFEOM arises from heterozygous missense mutations of KIF21A or TUBB3. Although spatiotemporal expression studies have shown KIF21A and TUBB3 expression in developing retinal ganglion cells, it is unclear whether dysinnervation extends beyond the oculomotor system. We aimed to investigate whether dysinnervation extends to the visual system by performing high-resolution optical coherence tomography (OCT) scans characterizing retinal ganglion cells within the optic nerve head and retina. Sixteen patients with CFEOM were screened for mutations in KIF21A, TUBB3, and TUBB2B. Six patients had apparent optic nerve hypoplasia. OCT showed neuro-retinal rim loss. Disc diameter, rim width, rim area, and peripapillary nerve fiber layer thickness were significantly reduced in CFEOM patients compared to controls (p < 0.005). Situs inversus of retinal vessels was seen in five patients. Our study provides evidence of structural optic nerve and retinal changes in CFEOM. We show for the first time that there are widespread retinal changes beyond the retinal ganglion cells in patients with CFEOM. This study shows that the phenotype in CFEOM extends beyond the motor nerves.

KIF21A pathogenic variants cause congenital fibrosis of extraocular muscles type 3

Background: Congenital fibrosis of the extraocular muscles (CFEOM) is characterized by ptosis and non-progressive restrictive ophthalmoplegia. CFEOM1 is a stereotypical phenotype with isolated bilateral ptosis, bilateral ophthalmoplegia, absent upgaze, and globe infraduction. CFEOM3 is a more variable phenotype that can include unilateral disease, absent ptosis, residual upgaze, and/or orthotropia. Most cases of CFEOM1 result from recurrent heterozygous KIF21A missense mutations and less commonly from recurrent heterozygous TUBB3 missense mutations. While most cases of CFEOM3 result from recurrent heterozygous TUBB3 missense mutations, several pedigrees harbored pathogenic variants in KIF21A. Here, we asked if Lebanese pedigrees with CFEOM3 harbor pathogenic variants in TUBB3 or KIF21A.Materials and Methods: Families affected with congenital cranial dysinnervation disorders were prospectively recruited from the American University of Beirut pediatric ophthalmology clinic and included two probands with CFEOM. KIF21A hotspot exons and TUBB3 coding sequence were sequenced. Available family members were sequenced for co-segregation analysis.Results: Both families were found to have CFEOM3 and to harbor pathogenic variants in KIF21A(OMIM 608283). A simplex proband with CFEOM3 from a consanguineous Iraqi family harbored a de novo heterozygous KIF21A c.2860 C > T variant (p.R954W); this variant accounts for the majority of reported KIF21A mutations but is typically implicated in CFEOM1. A Lebanese father with CFEOM3 and his son with CFEOM1 segregated a heterozygous KIF21A c.2830 G > C variant (p.E944Q), previously reported in an individual with CFEOM1.Conclusions: These results support prior reports of KIF21A mutations as a rare cause of CFEOM3. These families are Middle Eastern or Chinese, supporting a genetic modifier in these populations.

PD-L1 expression in the microenvironment and the response to checkpoint inhibitors in head and neck squamous cell carcinoma

In head and neck squamous cell carcinoma (HNSCC), data from studies using checkpoint-inhibiting antibodies that target programmed death 1 (PD-1) or its ligand the programmed death ligand 1 (PD-L1) demonstrated outstanding clinical activity. Translational investigations also suggested some correlations between therapeutic response and PD-L1 expression in tumor tissue. We comprehensively summarize results that have evaluated PD-L1 expression in HNSCC. We discuss flaws and strength of current PD-1/PD-L1 detection, quantification methods and the evaluation of PD-L1 as a prognostic and theragnostic biomarker. Understanding tumor microenvironment may help understanding resistance to checkpoint inhibitors, designing clinical trials that can exploit drug combinations.

Impact of the first month of Covid-19 lockdown on oncologic surgical activity in the Ile de France region university hospital otorhinolaryngology departments

OBJECTIVE

To evaluate the impact of the first month of lockdown related to the Covid-19 epidemic on the oncologic surgical activity in the Ile de France region university hospital otorhinolaryngology departments.

MATERIAL AND METHODS

A multicenter prospective observational assessment was conducted in 6 university hospital otorhinolaryngology departments (Paris Centre, Nord, Est and Sorbonne) during the 1-month periods before (Month A) and after (Month B) lockdown on March 17, 2020. The main goal was to evaluate lockdown impact on oncologic surgical activity in the departments. Secondary goals were to report population characteristics, surgery conditions, postoperative course, progression of Covid status in patients and surgeons, and adverse events.

RESULTS

224 procedures were performed. There was 10.9% reduction in overall activity, without significant difference between departments. Squamous cell carcinoma and larynx, hypopharynx, oropharynx, oral cavity and nasal cavity and sinus locations were predominant, at 79% and 75.8% of cases respectively, with no significant differences between months. T3/4 and N2/3 tumors were more frequent in Month B (P=.002 and .0004). There was no significant difference between months regarding surgical approach, type of reconstruction, postoperative course, tracheotomy and nasogastric feeding-tube time, intensive care stay or hospital stay. None of the Month A patients were Covid-19-positive, versus 3 in Month B, without adverse events. None of the otorhinolaryngologists involved in the procedures developed symptoms suggesting Covid-19 infestation.

CONCLUSION

The present study underscored the limited impact of the Covid-19 epidemic and lockdown on surgical diagnosis and cancer surgery in the Ile de France university otorhinolaryngology departments, maintaining chances for optimal survival without spreading the virus.

OP0167 SUCCESSFUL WITHDRAWAL OF MYCOPHENOLATE MOFETIL IN QUIESCENT SLE: RESULTS FROM A RANDOMIZED TRIAL

Background:

Trials and clinical observations have demonstrated the efficacy of mycophenolate mofetil (MMF) for SLE treatment. Long-term use of MMF is associated with adverse events, pregnancy risks, drug monitoring, and increased cost. Current management continues therapy indefinitely. Whether immunosuppression may be safely withdrawn or whether risks of withdrawal outweigh the benefits of continuation is unknown.

Objectives:

To compare rates of clinically significant disease reactivation (CSDR), major flares, and all flares in patients with quiescent SLE on stable MMF randomized to maintain or withdraw MMF. The goal is to provide guidance for clinicians and patients on the risks of MMF withdrawal.

Methods:

Adults with quiescent SLE (SELENA-SLEDAI without serologies <4) receiving MMF for ≥2 years for nephritis or ≥ 1 year for non-nephritis were randomized 1:1 to unblinded MMF (maintenance arm, MA) or to a 12-week taper off MMF (withdrawal arm, WA) and followed through 60 weeks. Subjects were on stable hydroxychloroquine; steroids limited to ≤ 10 mg. CSDR, defined as a SLEDAI flare requiring immunosuppression, BILAG flares and adverse events were assessed. Event rates and time to flare were compared using Kaplan-Meier.

Results:

102 subjects were randomized (50 MA, 52 WA); 1 subject in each arm was ineligible and 10 terminated early (7 MA, 3 WA). Mean disease duration was 13 years; 76% had a history of nephritis; mean baseline SLEDAI was 2.2. 5 MA subjects (10%) had CSDR, compared to 9 WA (17%). Median time to CDSR was 38 weeks in both arms. BILAG A flares occurred in 1MA subject (pancreatitis) vs. 4 WA (cranial neuropathy, panniculitis, 2 nephritis). Kaplan-Meier curves overlapped for CDSR, BILAG A flares, and all SLEDAI flares (Figure). Based on these data, we are 86% confident that the increased risk of CDSR with MMF withdrawal is less than 15% over 60 weeks. AEs were similar between groups; infections occurred more commonly in MA (63 vs. 49).

Conclusion:

In this cohort of subjects with quiescent SLE on long term MMF serious flares occurred infrequently in subjects continuing or withdrawing MMF without differences in time to flare. MMF withdrawal may be considered in subjects with prolonged quiescent disease.

Table 1.

Baseline and Demographic Characteristics

Maintenance armWithdrawal armTotalRandomized5052102Female, n (%)39 (78)47 (90)86 (84)White, n (%)25 (50)19 (37)44 (43)Black, n (%)19 (38)22 (42)41 (40)Hispanic/Latino, n (%)10 (20)12 (23)22 (22)Age, Years, mean (SD)42.4 (12.9)41.6 (12.5)42.0 (12.6)Disease Duration, Years, mean (SD)13.6 (8.2)12.2 (7.9)12.9 (8.0)H/O Lupus Nephritis, n (%)40 (80)38 (73)78 (76.5)On Baseline Steroids, n (%)18 (36)23 (44)41 (40)Prednisone Dose, mg, mean (SD)4.8 (2.7)3.3 (1.7)4.0 (2.3)MMF Duration, Years, mean (SD)6.8 (4.3)6.4 (4.3)6.6 (4.3)Baseline MMF Dose, mg, mean1,6121,6681,640SELENA-SLEDAI*, mean (SD)2.4 (1.76)1.9 (1.76)2.2 (1.77)Positive DsDNA, n (%)35 (70)27 (52)62 (61)Low C31, n (%)14 (28)9 (17)23 (23)Low C41, n (%)6 (12)5 (10)11 (11)Figure.

Kaplan-Meier Estimates of Flare Endpoints

Disclosure of Interests:

Eliza Chakravarty: None declared, Tammy Utset: None declared, Diane L Kamen Consultant of: Consulted on SLE survey development for Lilly and consulted on SLE trial protocol development for EMD Serono in 2019, Gabriel Contreras Grant/research support from: Genentech, Merck, Consultant of: Genentech, Merck, William Joseph McCune: None declared, Kenneth C Kalunian: None declared, Cynthia Aranow: None declared, Megan Clowse Grant/research support from: GSK, Pfizer, Consultant of: UCB, Astra-Zeneca, Speakers bureau: UCB, Ellen Goldmuntz: None declared, Jessica Springer: None declared, Lynette Keyes-Elstein: None declared, Bill Barry: None declared, Ashley Pinckney: None declared, Judith James: None declared

Consensus français sur la pratique de la chirurgie oncologique ORL pendant la pandémie de COVID-19

Dans le contexte de la pandémie de COVID-19, des conseils spécifiques semblent nécessaires concernant la prise en charge des patients atteints de cancers ORL. La règle est de limiter au maximum le flux de patients afin de réduire les risques de contamination par le virus SARS-Cov-2 aussi bien des patients que du personnel soignant, particulièrement exposé en ORL. L’objectif est de limiter le risque de perte de chance pour le patient et d’anticiper le flux de patients atteints de cancers à traiter à la fin de l’épidémie, en tenant compte du degré d’urgence, de la lourdeur de la chirurgie, du risque de contamination de l’équipe soignante (trachéotomie) et de la situation locale (saturation ou non de l’hôpital et des services de réanimation).

French consensus regarding precautions during tracheostomy and post-tracheostomy care in the context of COVID-19 pandemic

Tracheostomy post-tracheostomy care are regarded as at high risk for contamination of health care professionals with the new coronavirus (SARS-CoV-2). Considering the rapid spread of the infection, all patients in France must be considered as potentially infected by the virus. Nevertheless, patients without clinical or radiological (CT scan) markers of COVID-19, and with negative nasopharyngeal sample within 24h of surgery, are at low risk of being infected. Instructions for personal protection include specific wound dressings and decontamination of all material used. The operating room should be ventilated after each tracheostomy and the pressure of the room should be neutral or negative. Percutaneous tracheostomy is to be preferred over surgical cervicotomy in order to reduce aerosolization and to avoid moving patients from the intensive care unit to the operating room. Ventilation must be optimized during the procedure, to limit patient oxygen desaturation. Drug assisted neuromuscular blockage is advised to reduce coughing during tracheostomy tube insertion. An experienced team is mandatory to secure and accelerate the procedure as well as to reduce risk of contamination.

French consensus on management of head and neck cancer surgery during COVID-19 pandemic

In the context of the current pandemic, there is a need for specific advice concerning treatment of patients with Head and Neck cancers. The rule is to limit as much as possible the number of patients in order to reduce the risks of contamination by the SARS-Cov-2 virus for both patients and the caregivers, who are particularly exposed in ENT. The aim is to minimize the risk of loss of opportunity for patients and to anticipate the increased number of cancer patients to be treated at the end of the pandemic, taking into account the degree of urgency, the difficulty of the surgery, the risk of contaminating the caregivers (tracheotomy) and the local situation (whether or not the hospital and intensive care departments are overstretched).

COVID-19 and ENT Surgery

In Otorhinolaryngology – Head and Neck Surgery, clinical examination and invasive procedures on the respiratory tract and on airway-connected cavities, such as paranasal sinuses and the middle ear, expose people to direct transmission of SARS-CoV-2 by inhalation or ocular projection of contaminated droplets, and to indirect transmission by contact with contaminated hands, objects or surfaces. Estimating an R₀ of COVID-19 at around 3 justified postponing non-urgent face-to-face consultations and expanding the use of teleconsultation in order to limit the risks of SARS-CoV-2 infection of patients or health workers and comply with the lockdown. The health authority recommends cancellation of all medical or surgical activities, which are not urgent as long as this does not involve a loss of chance for the patient. The purpose of this cancellation is to significantly increase critical care capacity, prioritise the reception of patients with COVID-19, prioritise the allocation of staff and provision of the equipment necessary for their medical or surgical management, and contribute to the smooth running of downstream critical care within their establishment. Another goal is to reduce the risks of patient contamination within healthcare facilities. This document provides guidance on how to proceed with and adapt ENT surgery in the current pandemic context, as well as on the management of postponed operations. This best practice advice must of course be adapted in each region according to the development of the epidemic and pre-existing arrangements. Their local application can only be decided within the framework of collaboration between the ENT teams, the operational hygiene units and all the other specialties concerned.

MAGEL2-related disorders: A study and case series

Pathogenic MAGEL2 variants result in the phenotypes of Chitayat-Hall syndrome (CHS), Schaaf-Yang syndrome (SYS) and Prader-Willi syndrome (PWS). We present five patients with mutations in MAGEL2, including the first patient reported with a missense variant, adding to the limited literature. Further, we performed a systematic review of the CHS and SYS literature, assess the overlap between CHS, SYS and PWS, and analyze genotype-phenotype correlations among them. We conclude that there is neither a clinical nor etiological difference between CHS and SYS, and propose that the two syndromes simply be referred to as MAGEL2-related disorders.

Congenital monocular elevation deficiency associated with a novel TUBB3 gene variant

Background

The genetic basis of monocular elevation deficiency (MED) is unclear. It has previously been considered to arise due to a supranuclear abnormality.

Methods

Two brothers with MED were referred to Leicester Royal Infirmary, UK from the local opticians. Their father had bilateral ptosis and was unable to elevate both eyes, consistent with the diagnosis of congenital fibrosis of extraocular muscles (CFEOM). Candidate sequencing was performed in all family members.

Results

Both affected siblings (aged 7 and 12 years) were unable to elevate the right eye. Their father had bilateral ptosis, left esotropia and bilateral limitation of elevation. Chin up head posture was present in the older sibling and the father. Bell’s phenomenon and vertical rotational vestibulo-ocular reflex were absent in the right eye for both children. Mild bilateral facial nerve palsy was present in the older sibling and the father. Both siblings had slight difficulty with tandem gait. MRI revealed hypoplastic oculomotor nerve. Left anterior insular focal cortical dysplasia was seen in the older sibling. Sequencing of TUBB3 revealed a novel heterozygous variant (c.1263G>C, p.E421D) segregating with the phenotype. This residue is in the C-terminal H12 α-helix of β-tubulin and is one of three putative kinesin binding sites.

Conclusion

We show that familial MED can arise from a TUBB3 variant and could be considered a limited form of CFEOM. Neurological features such as mild facial palsy and cortical malformations can be present in patients with MED. Thus, in individuals with congenital MED, consideration may be made for TUBB3 mutation screening.

Abstract GS3-07: Genome-wide copy number analysis of chemotherapy-resistant metastatic triple-negative breast cancer from cell-free DNA

Introduction:

Triple-negative breast cancer (TNBC) is a poor prognosis breast cancer subset characterized by relatively few mutations but extensive copy number alterations (CNAs). Cell-free DNA (cfDNA) offers the potential to overcome infrequent tumor biopsies in metastatic TNBC (mTNBC) and interrogate the genomics of chemotherapy resistance.

Methods:

506 archival or fresh plasma samples were identified from 164 patients with mTNBC who had previously received chemotherapy. We performed low coverage whole genome sequencing to determine genome-wide copy number and estimate 'tumor fraction' of cfDNA (TFx) using our recently-developed approach, ichorCNA. In patient samples with TFx &gt;10%, we identified regions that were significantly gained or lost using GISTIC2.0. We compared CNAs of 20 paired primary-metastatic samples and also mTNBCs from cfDNA versus primary TNBCs from TCGA and METABRIC.

Results:

We successfully obtained high quality, low coverage whole genome sequencing data for 478 (94.5%) plasma samples from 158 patients, with 1 to 14 samples per patient. TFx and copy number profiles were highly concordant with paired metastatic biopsy (n=10, range 0-7 days from biopsy to blood draw) with sensitivity of 0.86 and specificity of 0.90 and reproducible in independently-processed blood draws (TFx intraclass correlation coefficient 0.984). Median overall survival from time of first blood draw was 8 months, and TFx was highly correlated independent of primary stage, primary receptor status, age at primary diagnosis, BRCA status, and metastatic line of therapy: adjusted hazard ratio between 4th and 1st quartiles = 2.14 (95% CI 1.40-3.28; p=0.00049). 101/158 patients (63.9%) had at least one sample with TFx &gt;10%, our threshold for high confidence CNA calls. Copy number profiles and percent genome altered were remarkably similar between mTNBCs and primary TNBCs in TCGA and METABRIC (n=433), suggesting that large-scale chromosomal events are infrequent in TNBC metastatic progression. We identified chromosomal gains that demonstrated significant enrichment in mTNBCs relative to paired primary TNBCs (n=20) and also TCGA/METABRIC, including driver genes (NOTCH2, AKT2, AKT3) and putative antibody-drug conjugate targets. Finally, we identify a novel association of gains of 18q11 and/or 19p13 with poor metastatic prognosis, independent of clinicopathologic factors and TFx.

Conclusions:

Here, we present the first large-scale genomic characterization of metastatic TNBC to our knowledge, derived exclusively from cfDNA. 'Tumor fraction' of cfDNA is an independent prognostic marker in mTNBC. Primary and metastatic TNBC have remarkably similar copy number profiles yet we identify alterations enriched and prognostic in mTNBC. Collectively, these data have potential implications in the understanding of metastasis, therapeutic resistance, and novel therapeutic targets.

Citation Format: Stover DG, Parsons HA, Ha G, Freeman S, Barry B, Guo H, Choudhury A, Gydush G, Reed S, Rhoades J, Rotem D, Hughes ME, Dillon DA, Partridge AH, Wagle N, Krop IE, Getz G, Golub TA, Love JC, Winer EP, Tolaney SM, Lin NU, Adalsteinsson VA. Genome-wide copy number analysis of chemotherapy-resistant metastatic triple-negative breast cancer from cell-free DNA [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr GS3-07.

Abstract P3-08-07: Margins in breast conserving surgery after neoadjuvant therapy

Background:The margin consensus guideline for patients undergoing primary breast conserving surgery (BCS) and whole breast radiotherapy defines a negative margin as no tumor on ink and concludes that wider margins do not improve local recurrence (LR) rates. There are few studies examining BCS margin width after neoadjuvant chemotherapy (NAC).We sought to determine the impact of margin width on LR and survival rates after NAC and BCS. Methods: Institutional database were reviewed to identify patients with stage I-III breast cancer treated with NAC and BCS from 2002-2014. Patients with inflammatory breast cancer were excluded. Chart review was performed to collect detailed patient and treatment factors. Margins widths were collected as reported and grouped as: positive (ink on tumor), close (&lt;2mm), and negative (&gt;2mm), for the purposes of this analysis. Cox regression was used to determine the relationship between margin width and local recurrence, disease free survival (DFS) and overall survival (OS). Result: 395 patients underwent NAC followed by BCS during the study period. The result was same as below.

results Patients, n (%)Age at diagnosis (yrs)51 [22;79]Initial tumor size (cm)3.0 [0.6;11.0]Clinical node status - negative207 (52.4%)- positive188 (47.6%)subtype - HR-/Her2-148 (37.5%)- HR-/Her2+48 (12.2%)- HR+/Her2-124 (31.4%)- HR+/Her2+72 (18.2%)- unclassified3 ( 0.8%)pCR* status - pCR97 (24.6%)- non pCR295 (74.7%)- unclassified3 ( 0.8%)Final margin state - no residual tumor in breast108 (27.3%)- positive8 ( 2.0%)- close (≤2)99 (25.1%)- negative (&gt;2)180 (45.6%)*pCR was defined as no invasive or in situ disease in breast and no tumor in axillary node

Median patient age was 51 yrs (range 22-79); median tumor size at presentation was 3.0 cm (range 0.6-11.0) and 188 (47.6%) patients (pts) presented with clinically node positive disease. Breast cancer subtypes included 148 (37.5%) pts with HR-/Her2-, 48 (12.2%) pts with HR-/Her2+, 124 (31.4%) pts with HR+/Her2- and 72 (18.2%) pts with HR+/Her2+, disease. Among all patients the pCR rate, defined as no invasive or in situ disease, in the breast was 27.3% (108/395) and the pCR rate in the breast and axillary nodes was 24.6% (97/395). Final margin status included 8 (2.0%) pts with positive margins, 99 (25.1%) with close &lt;2mm and 180 (45.6%) with negative (&gt;2mm) margins. Among the patients with “positive margins”; all were noted to be posterior or anterior and the surgeon noted that re-excision was not possible. At a median follow-up of 53.0 months the LR rate was 2.8% and DFS was 87.4%. On cox regression, HR positive subtype (p=0.048), pCR (p=0.035), and pathologic negative node (p&lt;0.001) were correlated with favorable DFS and pathologic negative node (p&lt;0.001) was correlated with favorable OS. There was no difference in LR rate, DFS or OS between 'close/positive margin' and '&gt;2mm margin groups. Conclusion: In this cohort of patients treated with NAC followed by BCS, LR rates were very low and there was no difference in DFS between patients with margins &lt; 2mm or &gt; 2mm. Further studies are needed to confirm the effect of margin width in the NAC setting.

Citation Format: Choi J, Golshan M, Hu J, Gagnon HC, Densantis S, Barry B, King T. Margins in breast conserving surgery after neoadjuvant therapy [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P3-08-07.

Optimal conditions for flexible methane production in a demand-based operation of biogas plants

The aim of the presented work was to study the methane production limits and to determine optimal conditions for flexible operation of an anaerobic reactor in order to set up an operational strategy. Punctual overloads were conducted in a laboratory-scale anaerobic reactor with readily biodegradable solid substrates, and the influences of overload intensity, baseload value and substrate used were investigated. A maximal daily value around 1000mL/L of reactor for methane production has been assessed. This value did not evolve significantly during experiment time, and conditioned the persistence of overloads as well as the flexibility margin on the reactor, which ranged from +25% to +140% on daily production. Results highlighted the fact that for a maximum flexibility, low organic loading rates are better to work with on this type of reactors.

Disorders of Microtubule Function in Neurons: Imaging Correlates

BACKGROUND AND PURPOSE

A number of recent studies have described malformations of cortical development with mutations of components of microtubules and microtubule-associated proteins. Despite examinations of a large number of MRIs, good phenotype-genotype correlations have been elusive. Additionally, most of these studies focused exclusively on cerebral cortical findings. The purpose of this study was to characterize imaging findings associated with disorders of microtubule function.

MATERIALS AND METHODS

MRIs from 18 patients with confirmed tubulin mutations (8 TUBA1A, 5 TUBB2B, and 5 TUBB3) and 15 patients with known mutations of the genes encoding microtubule-associated proteins (5 LIS1, 4 DCX, and 6 DYNC1H1) were carefully visually analyzed and compared. Specific note was made of the cortical gyral pattern, basal ganglia, and white matter to assess internal capsular size, cortical thickness, ventricular and cisternal size, and the size and contours of the brain stem, cerebellar hemispheres and vermis, and the corpus callosum of patients with tubulin and microtubule-associated protein gene mutations. Results were determined by unanimous consensus of the authors.

RESULTS

All patients had abnormal findings on MR imaging. A large number of patients with tubulin gene mutations were found to have multiple cortical and subcortical abnormalities, including microcephaly, ventriculomegaly, abnormal gyral and sulcal patterns (termed "dysgyria"), a small or absent corpus callosum, and a small pons. All patients with microtubule-associated protein mutations also had abnormal cerebral cortices (predominantly pachygyria and agyria), but fewer subcortical abnormalities were noted.

CONCLUSIONS

Comparison of MRIs from patients with known mutations of tubulin genes and microtubule-associated proteins allows the establishment of some early correlations of phenotype with genotype and may assist in identification and diagnosis of these rare disorders.

[Human papilloma virus in head and neck cancer]

Head and neck cancer is frequently associated with alcohol and tobacco consumption but there is an increasing incidence of oropharyngeal carcinoma associated with oncogenic type-16 human papillomavirus (HPV). The clinical profile of these patients is distinct from that of other patients, with an earlier onset, 1/1 male to female sex ratio, cystic cervical nodes. Detection of intratumoral viral DNA is essential to confirm the role of HPV. According to several reports, the prognosis in terms of survival and locoregional control is better in HPV-positive oropharyngeal carcinoma than in HPV-negative oropharyngeal carcinoma or associated with tobacco consumption. The future lies in vaccination of women against cervical cancer but vaccination of boys will be certainly necessary.

SLC25A22 is a novel gene for migrating partial seizures in infancy

OBJECTIVE

To identify a genetic cause for migrating partial seizures in infancy (MPSI).

METHODS

We characterized a consanguineous pedigree with MPSI and obtained DNA from affected and unaffected family members. We analyzed single nucleotide polymorphism 500K data to identify regions with evidence of linkage. We performed whole exome sequencing and analyzed homozygous variants in regions of linkage to identify a candidate gene and performed functional studies of the candidate gene SLC25A22.

RESULTS

In a consanguineous pedigree with 2 individuals with MPSI, we identified 2 regions of linkage, chromosome 4p16.1-p16.3 and chromosome 11p15.4-pter. Using whole exome sequencing, we identified 8 novel homozygous variants in genes in these regions. Only 1 variant, SLC25A22 c.G328C, results in a change of a highly conserved amino acid (p.G110R) and was not present in control samples. SLC25A22 encodes a glutamate transporter with strong expression in the developing brain. We show that the specific G110R mutation, located in a transmembrane domain of the protein, disrupts mitochondrial glutamate transport.

INTERPRETATION

We have shown that MPSI can be inherited and have identified a novel homozygous mutation in SLC25A22 in the affected individuals. Our data strongly suggest that SLC25A22 is responsible for MPSI, a severe condition with few known etiologies. We have demonstrated that a combination of linkage analysis and whole exome sequencing can be used for disease gene discovery. Finally, as SLC25A22 had been implicated in the distinct syndrome of neonatal epilepsy with suppression bursts on electroencephalogram, we have expanded the phenotypic spectrum associated with SLC25A22.

G-protein coupled receptor 56 promotes myoblast fusion through serum response factor- and nuclear factor of activated T-cell-mediated signalling but is not essential for muscle development in vivo

Mammalian muscle cell differentiation is a complex process of multiple steps for which many of the factors involved have not yet been defined. In a screen to identify the regulators of myogenic cell fusion, we found that the gene for G-protein coupled receptor 56 (GPR56) was transiently up-regulated during the early fusion of human myoblasts. Human mutations in the gene for GPR56 cause the disease bilateral frontoparietal polymicrogyria; however, the consequences of receptor dysfunction on muscle development have not been explored. Using knockout mice, we defined the role of GPR56 in skeletal muscle. GPR56(-/-) myoblasts have decreased fusion and smaller myotube sizes in culture. In addition, a loss of GPR56 expression in muscle cells results in decreases or delays in the expression of myogenic differentiation 1, myogenin and nuclear factor of activated T-cell (NFAT)c2. Our data suggest that these abnormalities result from decreased GPR56-mediated serum response element and NFAT signalling. Despite these changes, no overt differences in phenotype were identified in the muscle of GPR56 knockout mice, which presented only a mild but statistically significant elevation of serum creatine kinase compared to wild-type. In agreement with these findings, clinical data from 13 bilateral frontoparietal polymicrogyria patients revealed mild serum creatine kinase increase in only two patients. In summary, targeted disruption of GPR56 in mice results in myoblast abnormalities. The absence of a severe muscle phenotype in GPR56 knockout mice and human patients suggests that other factors may compensate for the lack of this G-protein coupled receptor during muscle development and that the motor delay observed in these patients is likely not a result of primary muscle abnormalities.

[Target volumes in cervical lympadenopathies of unknown primary: toward a selective customized approach? On behalf of REFCOR]

The treatment of carcinomas of unknown primary revealed by cervical lymphadenopathy is based on neck dissection and nodal and pan-mucosal irradiation to control the neck and avoid the emergence of a metachronous primary. The aim of this review was to assess diagnostic and therapeutic approaches and criteria that may be used for a customized selective approach to avoid severe toxicities of pan-mucosal irradiation. A literature search was performed with the following keywords: cervical lymphadenopathy, unknown primary, upper aerodigestive tract, cancer, radiotherapy, squamous cell carcinoma, variants. The diagnostic workup includes a head and neck scanner or MRI, ((18)F)-FDG PET CT, a panendoscopy and tonsillectomy. Squamous cell carcinoma represents over two thirds of cases. The number of metastatic cervical nodes, nodal level, and histological variant (associated with HPV/EBV status) may determine the primary site origin and might be weighted for the determination of radiation target volumes on a multidisciplinary basis. A selective customized approach is relevant to decrease radiation toxicity only if neck and mucosal control is not impaired. Although no recommendation can yet be made in the absence of sufficient level of evidence, the relevance of systematic pan-mucosal irradiation appears questionable in a number of clinical situations. Accordingly, a customized selective redefinition of target volumes may be discussed and be prospectively evaluated in relation to the therapeutic index obtained.

Schizencephaly: association with young maternal age, alcohol use, and lack of prenatal care

Schizencephaly is a rare malformation of cortical development characterized by congenital clefts extending from the pial surface to the lateral ventricle that are lined by heterotopic gray matter. The clinical presentation is variable and can include motor or cognitive impairment and epilepsy. The causes of schizencephaly are heterogeneous and can include teratogens, prenatal infection, or maternal trauma. Reported genetic causes include chromosomal aneuploidy, EMX2 mutations, and possible autosomal recessive familial cases based on recurrence in siblings. In an effort to identify risk factors for schizencephaly, we conducted a survey of 48 parents or primary caretakers of patients with schizencephaly born between 1983 and 2004. We discovered that young maternal age, lack of prenatal care, and alcohol use were all significantly associated with risk of schizencephaly. Our results suggest that there are important nongenetic, intrauterine events that predispose to schizencephaly.

Initial staging of squamous cell carcinoma of the oral cavity, larynx and pharynx (excluding nasopharynx). Part I: Locoregional extension assessment: 2012 SFORL guidelines

OBJECTIVES

To set out good practice guidelines for locoregional extension assessment of squamous cell carcinoma of the head and neck (excluding nasopharynx, nasal cavities and sinuses).

MATERIALS AND METHODS

A critical multidisciplinary review of the literature on locoregional extension assessment of squamous cell carcinoma of the head and neck was conducted, applying levels of evidence in line with the French health authority's (HAS) literature analysis guide of January 2000.

CONCLUSION

Based on the levels of evidence of the selected articles and on work-group consensus, graded guidelines are set out for clinical, endoscopic and imaging locoregional extension assessment of head and neck cancer.

Initial staging for squamous cell carcinoma of the mouth, larynx and pharynx (except nasopharynx). Part 3: general assessment. 2012 SFORL recommendations

OBJECTIVES

The French Society of Otorhinolaryngology (SFORL) set up a work group to draw up guidelines for initial staging of head and neck squamous cell carcinoma. Locoregional and remote extension assessment are dealt with in two separate reports. The present part 3 deals with the assessment of frequent associated symptoms and pathologies, requiring early treatment and the collection of data on a certain number of clinical and paraclinical parameters for therapeutic decision-making in the multidisciplinary team meeting.

MATERIALS AND METHODS

A multidisciplinary critical analysis of the literature was conducted. General assessment here covers screening, assessment and initial management of the following: usual risk factors (smoking, alcohol, HPV), the most frequent medical comorbidities, nutritional status, social and psychological status, dental status, pain and possible anemia. As oncologic management frequently associates surgery, radiation therapy and chemotherapy, the underlying examinations should be early, as part of initial staging. The levels of evidence for the examinations were estimated so as to grade guidelines, failing which expert consensuses were established.

RESULTS

The high rates of pain, malnutrition and anemia call for systematic screening and early management, especially as rapidly effective treatments exist. Assessing comorbidity and social and psychological status enables general health status to be assessed, along with possible contraindications to the usual treatments. Tracheal intubation problems may require intubation under flexible endoscopy or jet-ventilation by inter-cricothyroid catheterization from the diagnostic endoscopy stage. Assessment and adapted dental care should be conducted if radiation therapy is likely or certain.

CONCLUSION

Early management of symptoms and comorbidity and anticipation of subsequent treatment are intended to shorten initial staging time and to collate the data needed for therapeutic decision-making. This assessment should be performed at the same time as the locoregional and remote extension assessment, and is obviously to be adapted according to tumoral extension stage and the possible treatment options.

Location of periventricular nodular heterotopia is related to the malformation phenotype on MRI

BACKGROUND AND PURPOSE

Periventricular nodular heterotopia are common malformations of cortical development that are associated with many clinical syndromes and with many different neuroimaging phenotypes. The purpose of this study was to determine whether specific malformation phenotypes may be related to location, side, or number of PNH as assessed by MR imaging.

MATERIALS AND METHODS

MR images of 200 patients previously diagnosed with PNH were retrospectively analyzed. PNH were classified according to their location along the ventricles (anterior, posterior, or diffuse), side (unilateral or bilateral), and number of nodules (<5, 6-10, or >10). The cerebrum, brain stem and cerebellum were analyzed to assess associated anomalies. Associations between PNH location and the presence of other anomalies were tested by using Fisher exact test and χ2 test.

RESULTS

Posterior PNH were significantly associated with malformations of the cerebral cortex, diminished white matter volume, and mid-/hindbrain anomalies. Diffuse PNH were associated with diminished white matter volume, callosal "anomalies," and the presence of megacisterna magna. Unilateral PNH were strongly associated with cortical malformations.

CONCLUSIONS

Certain malformation complexes are associated with PNH in specific locations: posterior PNH with cerebral cortical and mid-/hindbrain malformations and diffuse PNH with callosal anomalies and megacisterna magna. Knowledge of these associations should allow more directed analyses of brain MR imaging in patients with PNH. In addition, knowledge of these associations may help to direct studies to elucidate the causes of these malformation complexes.

Laparoscopic extraperitoneal colostomy in elective abdominoperineal resection for cancer: a single surgeon experience

AIM

Parastomal herniation of end colostomies can be chronically debilitating for patients and a difficult problem to treat. To prevent parastomal hernia (PSH) formation an extraperitoneal colostomy (EPC) approach has been developed in open colorectal surgery and some studies have suggested a potential advantage to this approach. Here we describe our technique of laparoscopic extraperitoneal stoma formation and present our experience to date.

METHODS

We performed a retrospective analysis of consecutive patients undergoing a laparoscopic abdominoperineal resection between March 1999 and March 2011. We performed the EPC technique as follows: under laparoscopic guidance, a smooth tip instrument was used to gently separate the peritoneum from the posterior aponeurotic plane to create an extraperitoneal tunnel running from the skin incision to the left flank of the abdominal cavity to join the previously dissected paracolic gutter. The colon was exteriorized and the position was checked to ensure the absence of torsion or kinking.

RESULTS

Twenty-two patients underwent a standard laparoscopic abdominoperineal resection with total mesorectal excision. Colostomy was constructed extraperitoneally (EPC) or transperitoneally (TPC) in 12 and 10 patients respectively. There were five complications requiring operative intervention: two stomal necrosis and one surgical site infection in the TPC group and two small bowel occlusions in the EPC group. Four patients from the TPC group developed PSH at 24, 36, 48 and 72 months respectively while there were no cases of PSH in the EPC group.

CONCLUSION

Extraperitoneal laparoscopic colostomy showed a potential reduction of PSH in our series of patients.

[Auditory and vestibular findings in Fabry disease: a study of 25 patients]

PURPOSE

Fabry disease (FD, OMIM 301500) is an X-linked lysosomal storage disorder due to deficient activity of the enzyme alpha-galactosidase A. Males and females exhibit severe organ involvement. The high incidence of otological symptoms was recently reported.

PATIENTS AND METHODS

Monocentric and retrospective study of twenty-five patients with FD (13 families; seven males and 18 females). The patients underwent audiological assessment before initiation and during enzyme replacement therapy. We also analysed neurologic heart and kidney status.

RESULTS

Twenty patients (80%; 13 females and seven males) complained of otologic symptoms. Audiological evaluation showed a sensorineural hearing loss in 17 patients, bilateral in 16 out of them. Vestibular examination showed a functional impairment in two patients (one female, one male). Correlations were found between hearing loss and either kidney disease (73,3%), neurological complications (100%) and cardiomyopathy (80%). Fourteen patients (56%; seven females, seven males) received enzyme replacement therapy. Improvement or stabilization of the audiological evaluation was reported in seven patients, whereas worsening was observed in three patients.

CONCLUSION

This study confirms the high frequency of audiological involvements in females and males with FD. Our analysis suggests that the frequency of hearing loss is increased in the presence of renal or neurologic involvement or cardiomyopathy. There is no clinically significant efficacy of enzyme replacement therapy on hearing function. Although the pathophysiology remains unknown, a vascular mechanism responsible of the inner ear involvement seems to be privileged.

FLNA genomic rearrangements cause periventricular nodular heterotopia

OBJECTIVE

To identify copy number variant (CNV) causes of periventricular nodular heterotopia (PNH) in patients for whom FLNA sequencing is negative.

METHODS

Screening of 35 patients from 33 pedigrees on an Affymetrix 6.0 microarray led to the identification of one individual bearing a CNV that disrupted FLNA. FLNA-disrupting CNVs were also isolated in 2 other individuals by multiplex ligation probe amplification. These 3 cases were further characterized by high-resolution oligo array comparative genomic hybridization (CGH), and the precise junctional breakpoints of the rearrangements were identified by PCR amplification and sequencing.

RESULTS

We report 3 cases of PNH caused by nonrecurrent genomic rearrangements that disrupt one copy of FLNA. The first individual carried a 113-kb deletion that removes all but the first exon of FLNA. A second patient harbored a complex rearrangement including a deletion of the 3' end of FLNA accompanied by a partial duplication event. A third patient bore a 39-kb deletion encompassing all of FLNA and the neighboring gene EMD. High-resolution oligo array CGH of the FLNA locus suggests distinct molecular mechanisms for each of these rearrangements, and implicates nearby low copy repeats in their pathogenesis.

CONCLUSIONS

These results demonstrate that FLNA is prone to pathogenic rearrangements, and highlight the importance of screening for CNVs in individuals with PNH lacking FLNA point mutations.