IGH 3'RR recombination uncovers a non-germinal center imprint and c-MYC-dependent IGH rearrangement in unmutated chronic lymphocytic leukemia.

Chronic lymphocytic leukemia (CLL) is an incurable indolent non-Hodgkin lymphoma characterized by tumor B cells that weakly express a B-cell receptor. The mutational status of the variable region (IGHV) within the immunoglobulin heavy chain (IGH) locus is an important prognosis indicator and raises the question of the CLL cell of origin. Mutated IGHV gene CLL are genetically imprinted by activation-induced cytidine deaminase (AID). AID is also required for IGH rearrangements: class switch recombination and recombination between switch Mu (Sµ) and the 3' regulatory region (3'RR) (Sµ-3'RRrec). The great majority of CLL B cells being unswitched led us to examine IGH rearrangement blockade in CLL. Our results separated CLL into two groups on the basis of Sµ-3'RRrec counts per sample: Sµ-3'RRrecHigh cases (mostly unmutated CLL) and Sµ-3'RRrecLow cases (mostly mutated CLL), but not based on the class switch recombination junction counts. Sµ-3'RRrec appeared to be ongoing in Sµ-3'RRrecHigh CLL cells and comparison of Sµ-3'RRrec junction structural features pointed to different B-cell origins for both groups. In accordance with IGHV mutational status and PIM1 mutation rate, Sµ-3'RRrecHigh CLL harbor a non-germinal center experienced B-cell imprint while Sµ-3'RRrecLow CLL are from AID-experienced B cells from a secondary lymphoid organ. In addition to the proposals already made concerning the CLL cell of origin, our study highlights that analysis of IGH recombinatory activity can identify CLL cases from different origins. Finally, on-going Sµ-3'RRrec in Sµ-3'RRrecHigh cells appeared to presumably be the consequence of high c-MYC expression, as c-MYC overexpression potentiated IGH rearrangements and Sµ-3'RRrec, even in the absence of AID for the latter.

High prevalence of congenital deafness on Reunion Island is due to a founder variant of LHFPL5.

Reunion Island is a French oversea department in the Indian Ocean with 1.6/1000, an estimated prevalence of deafness that is almost double as compared to the mainland France. Twelve children having isolated bilateral prelingual profound deafness along with motor delay attributed to vestibular areflexia were enrolled. Their mean walking age was 19 months. Electroretinography and temporal bone CT-scans were normal in all cases. A novel homozygous frameshift lipoma HMGIC fusion partner-like 5 (LHFPL5) variant c.185delT p.(Phe62Serfs*23) was identified using whole-exome sequencing. It was found in seven families. Four patients from two different families from both Reunion Island and mainland France, were compound heterozygous: c.185delT p.(Phe62Serfs*23) and c.472C > T p.(Arg158Trp). The phenotype observed in our patients completely mimics the hurry-scurry (hscy) murine Tmhs knock-out model. The recurrent occurrence of same LHFPL5 variant in Reunion Island is attributed to common ancestor couple born in 1693.

A novel pathogenic variant of NEFL responsible for deafness associated with peripheral neuropathy discovered through next-generation sequencing and review of the literature.

Neurofilaments are neuron-specific intermediate filaments essential for the radial growth of axons during development and the maintenance of axonal diameter. Pathogenic variants of Neurofilament Light (NEFL) are associated with CMT1F, CMT2E, and CMTDIG and have been observed in less than 1% of Charcot-Marie-Tooth (CMT) cases, resulting in the reporting of 35 variants in 173 CMT patients to date. However, only six variants have been reported in 17 patients with impaired hearing. No genotype-phenotype correlations have yet been established. Here, we report an additional case: a 69-year-old female, who originally presented with axonal sensory and motor neuropathy at the age of 45, associated with moderate sensorineural hearing loss, with a slight slope at high frequencies. Next-generation sequencing identified a novel pathogenic variant: c.269A > G, p.(Glu90Gly). Hearing impairment is often linked to CMT due to pathogenic variants of NEFL, especially p.(Glu90Lys) and p.(Asn98Ser), and in our case p.(Glu90Gly). These pathogenic variants are all located at hot spots, in the head domain and the two ends of the rod domain of the protein.

A complex homozygous mutation in ABHD12 responsible for PHARC syndrome discovered with NGS and review of the literature.

PHARC syndrome (MIM612674) is an autosomal recessive neurodegenerative pathology that leads to demyelinating Polyneuropathy, Hearing loss, cerebellar Ataxia, Retinitis pigmentosa, and early-onset Cataracts (PHARC). These various symptoms can appear at different ages. PHARC syndrome is caused by mutations in ABHD12 (α-ß hydrolase domain 12), of which several have been described. We report here a new complex homozygous mutation c.379_385delAACTACTinsGATTCCTTATATACCATTGTAGTCTTACTGCTTTTGGTGAACACA (p.Asn127Aspfs*23). This mutation was detected in a 36-year-old man, who presented neuropathic symptoms from the age of 15, using a next-generation sequencing panel. This result suggests that the involvement of ABHD12 in polyneuropathies is possibly underestimated. We then performed a comparative study of other patients presenting ABHD12 mutations and searched for genotype-phenotype correlations and functional explanations in this heterogeneous population.

An Application of NGS for Molecular Investigations in Perrault Syndrome: Study of 14 Families and Review of the Literature.

Perrault syndrome (PS) is a rare autosomal recessive condition characterized by deafness and gonadic dysgenesis. Recently, mutations in five genes have been identified: C10orf2, CLPP, HARS2, HSD17B4, and LARS2. Probands included are presented with sensorineural deafness associated with gonadic dysgenesis. DNA was sequenced using next-generation sequencing (NGS) with a panel of 35 deafness genes including the five Perrault genes. Exonic variations known as pathogenic mutations or detected with <1% frequency in public databases were extracted and subjected to segregation analysis within each family. Both mutations and low coverage regions were analyzed by Sanger sequencing. Fourteen female index patients were included. The screening in four cases has been extended to four family members presenting with PS phenotype. For four unrelated patients (28.6%), causative mutations were identified: three homozygous mutations in C10orf2, CLPP, and HARS2, and one compound heterozygous mutation in LARS2. Three additional heterozygous mutations in LARS2 and HSD17B4 were found in three independent familial cases. All these missense mutations were verified by Sanger sequencing. Familial segregation analyses confirmed the molecular diagnosis in all cases carrying biallelic mutations. Because of NGS, molecular analysis confirmed the clinical diagnosis of PS in 28.6% of our cohort and four novel mutations were found in four Perrault genes. For the unsolved cases, exome sequencing should be performed to search for a sixth unknown PS gene.

Transoral robotic surgery for the treatment of head and neck cancer of various localizations.

BACKGROUND: Transoral robotic surgery (TORS) is a recent endoscopic technique to resect selected head and neck cancers. STUDY DESIGN: In total, 13 patients underwent TORS procedure for resection of head and neck cancers of various localizations, within the ENT Department of Limoges University Hospital Center between March and October 2010. RESULTS: Tumor localizations were aryepiglottic fold (n = 3), pyriform sinus (n = 2), posterior pharyngeal wall (n = 2), base of tongue (n = 2), lateral pharyngeal wall (n = 2), vallecula (n = 1), and epiglottis (n = 1). Average TORS setup time was 23 minutes. Average TORS operative time was 45 minutes. Average hospital stay was 8.4 days. CONCLUSIONS: TORS is a new technique that permits excellent resection of selected head and neck cancers with poor morbidity. Future reports on long-term oncologic and functional outcomes are needed to assess the risks and benefits of this approach compared with external approaches and nonsurgical alternatives.

History of tonsillectomy and risk of oropharyngeal cancer.

OBJECTIVE: To investigate whether palatine tonsillectomy in youth influences the risk of oropharyngeal cancers (OPC) by assessing the association between history of tonsillectomy and risk of tonsillar, base of tongue (BOT) cancer, and other head and neck cancers (HNC). MATERIALS AND METHODS: RACKAM was a case-case study comparing frequency of tonsillectomy history in individuals diagnosed with HNC from 2013 to 2018 in 15 centers across France. History of tonsillectomy was defined using combined assessment of patients' recollections and surgeons' visualizations of tonsil area. OPC subsite-specific odds ratios (OR) of tonsillectomy were calculated using multinomial logistic regression with non-oropharyngeal HNC as reference. RESULTS: 1045 patients were included in the study. Frequency of tonsillectomy was 19.5% in patients with tonsillar cancer (N = 85), 49.3% in BOT (N = 76), 33.8% in other oropharyngeal cancers (N = 202) and 38.0% in non-oropharyngeal HNC (N = 682). History of tonsillectomy was inversely associated with tonsillar cancer (adjusted OR 0.4; 95% CI 0.2-0.8), and positively associated with BOT cancer (adjusted OR 1.8; 95% CI 1.1-3.1), but was not associated with all OPC combined (adjusted OR 1.1; 95% CI 0.8-1.4). Sensitivity analyses considering only patients' or surgeons' assessments of tonsillectomy provided comparable results. CONCLUSION: We confirm the long-term protective effect of tonsillectomy performed in youth on future risk of tonsillar cancer, and our study is the second to report a concurrent increased risk of BOT cancer. Our data suggest that tonsillectomy in youth shifts the site of the first diagnosed oropharyngeal tumor and has a limited impact on overall risk of OPC.

New PRPS1 variant p.(Met68Leu) located in the dimerization area identified in a French CMTX5 patient.

BACKGROUND: CMTX5 is characterized by peripheral neuropathy, early-onset sensorineural hearing impairment, and optic neuropathy. Only seven variants have been reported and no genotype-phenotype correlations have yet been established. PRPS1 has a crystallographic structure, as it is composed of three dimers that constitute a hexamer. METHODS: Next-generation sequencing (NGS) was performed using a custom 92-gene panel designed for the diagnosis of Charcot-Marie-Tooth (CMT) and associated neuropathies. RESULTS: We report the case of a 35-year-old male, who had presented CMT and hearing loss since childhood associated to bilateral optic neuropathy without any sign of retinitis pigmentosa. A new hemizygous variant on chromosomic position X:106,882,604, in the PRPS1 gene, c.202A > T, p.(Met68Leu) was found. This change is predicted to lead to an altered affinity between the different subunits in the dimer, thereby may prevent the hexamer formation. CONCLUSION: CMTX5 is probably under-diagnosed, as an overlap among the different features due to PRPS1 exists. Patients who developed polyneuropathy associated to sensorineural deafness and optic atrophy during childhood should be assessed for PRPS1.

Hearing loss in inherited peripheral neuropathies: Molecular diagnosis by NGS in a French series.

BACKGROUND: The most common inherited peripheral neuropathy is Charcot-Marie-Tooth disease (CMT), with a prevalence of 1/2500. Other symptoms can be associated to the condition, such as hearing loss. Currently, no global hearing impairment assessment has been determined, and the physiopathology is not well known. METHODS: The aim of the study was to analyze among a French series of 3,412 patients with inherited peripheral neuropathy (IPN), the ones who also suffer from hearing loss, to establish phenotype-genotype correlations. An NGS strategy for IPN one side and nonsyndromic hearing loss (NSHL) on the other side, were performed. RESULTS: Hearing loss (HL) was present in only 44 patients (1.30%). The clinical data of 27 patients were usable. Demyelinating neuropathy was diagnosed in 15 cases and axonal neuropathy in 12 cases. HL varied from mild to profound. Five cases of auditory neuropathy were noticed. Diagnosis was made for 60% of these patients. Seven novel pathogenic variants were discovered in five different genes: PRPS1; MPZ; SH3TC2; NEFL; and ABHD12. Two patients with PMP22 variant, had also an additional variant in COCH and MYH14 respectively. No pathogenic variant was found at the DFNB1 locus. Genotype-phenotype correlations do exist, especially with SH3TC2, PRPS1, ABHD12, NEFL, and TRPV4. CONCLUSION: Involvement of PMP22 is not enough to explain hearing loss in patients suffering from IPN. HL can be due to cochlear impairment and/or auditory nerve dysfunction. HL is certainly underdiagnosed, and should be evaluated in every patient suffering from IPN.

[Cyto-histological correlation in the management of parotid gland tumors: A retrospective study of 160 cases]. / Corrélation cyto-histologique dans la prise en charge des tumeurs parotidiennes : étude rétrospective de 160 cas.

INTRODUCTION: The aim of this study was to correlate the cytological and histological results and evaluate the diagnostic performance of fine-needle aspiration cytology (FNAC) in the management of parotid gland tumors. METHODS: This retrospective study included 160 patients with a parotid gland tumor who underwent fine-needle aspiration and parotidectomy surgery between January 2005 and August 2016 at the Limoges university hospital center. RESULTS: On 160 fine-needle aspirations performed, fine-needle aspiration diagnoses were: 77 benign lesions, 35 malignant lesions and 48 non-diagnostic cases. Final histological diagnosis revealed there were 113 benign lesions and 47 malignant lesions. A hundred and one cytological diagnoses were accurate over 112 contributive fine-needle aspirations: seven false-negative cases and 4 false-positive cases were observed. The sensitivity, specificity, and accuracy were 82, 95 and 90% respectively for fine-needle aspiration, and 83, 95 and 92% respectively for association of fine-needle aspiration and magnetic resonance imaging. Diagnostic concordance between fine-needle aspiration and final histology for malignant lesions was 78%. A greater number of contributive fine-needle aspirations was observed among experimented operators. DISCUSSION: Fine-needle aspiration is a reliable, safe and effective diagnostic tool that allows good differentiation between malignant and benign diagnosis in the preoperative management of parotid gland tumors. The association of fine-needle aspiration and magnetic resonance imaging (MRI) can improve diagnostic performance.

Endoscopic Submandibular Retropharyngeal Approach to the Craniocervical Junction and Clivus: an Anatomic Study.

INTRODUCTION: Surgery of the craniocervical junction (CCJ) and clivus is technically demanding. For many years, we have used the submandibular retropharyngeal approach for surgery of the upper cervical spine, especially hangman fracture. We hypothesized that submandibular gland resection could offer a significant cranial enlargement of the operative field, up to the clivus. Our aim in this work was to assess the feasibility of an endoscope-assisted retropharyngeal approach to the CCJ and clivus. METHODS: Eight anatomic specimens were used, including 4 silicon-injected specimens. We performed a submandibular retropharyngeal approach with gland resection, and then we exposed the CCJ and clivus. We drilled the C2 vertebral body, odontoid process, C1 anterior arch, and the clivus. We noted 8 anatomic landmarks that were easily identified on each anatomic specimen. These measurements were designed to quantify the exposure of the clivus and CCJ after bone resection. RESULTS: A submandibular approach was feasible in all specimens. The main dimensions of the area of dural exposure after bone drilling were as follows: mean width between C1 lateral masses, 19 mm (range, 17-20 mm); at the tip of the clival window, 18 mm (range, 16-20 mm); distance between the C3 vertebra and the tip of the window within the clivus, 57 mm (range, 55-60 mm). CONCLUSIONS: An endoscopic submandibular retropharyngeal approach provides a simple and straightforward access to the CCJ. It also conveniently exposes the clivus. This technique could be added to the techniques used for this difficult surgery.

An uncommon case of dyspnea with unilateral laryngeal paralysis in acromegaly.

A 61-year-old man with obstructive sleep apnea syndrome and normal BMI complained of dyspnea. Nasofibroscopy revealed a global and major oedema of the glottis and supraglottis and also a paralysis of the left vocal fold. CT-scan pointed out a spontaneous hyperdensity of the left arytenoid cartilage. A tracheostomy was performed. Clinical examination revealed large hands and macroglossy with high IGF1 rate. MRI confirmed a supracentimetric pituitary adenoma. To our knowledge, this is the first description of a case of acute respiratory distress due to unilateral larynx paralysis leading to acromegaly diagnosis. This is due to submucosal hypertrophy and vocal cord immobility.

Successful treatment of anterior tracheal necrosis after total thyroidectomy using vacuum-assisted closure therapy.

Total thyroidectomy involving the adjacent structures of the trachea can cause tracheal damage such as early tracheal necrosis. The authors describe the first case of anterior tracheal necrosis following total thyroidectomy treated using vacuum-assisted closure device. After two weeks of VAC therapy, there was no evidence of ongoing infection and the trachea was partially closed around a tracheotomy cannula, removed after 3 months. The use of a VAC therapy to reduce and close the tracheal rent and to create a rapid granulation tissue over tracheal structure appeared as a good opportunity after anterior tracheal necrosis.

Peripheral facial paralysis and bilateral carotid pseudoaneurysms of petrous localization: a case report.

Carotid pseudoaneurysms of petrous localization are rare. They are mostly due to trauma, tumoral or infectious diseases, or a result of iatrogenic complications after skull base surgery. Symptoms such as facial paralysis are exceptional and have rarely been described in the literature until now. We report the case of a 64-year-old woman, who developed left peripheral facial paralysis induced by two carotid pseudoaneurysms in their intrapetrous section. The treatment is endovascular, despite the high morbidity rate. She was first put on antiplatelet medications, before the left carotid aneurysm was bypassed thanks to a self-expanding pipeline-type stent with flow diversion. The left peripheral facial paralysis was due to the compression exerted by the left carotid aneurysm, probably a congenital malformation. The progressive palsy recovery was fist due to the aneurysmal thrombosis, then to the secondary fibrosis.