Identification of CTNNB1 mutations, CTNNB1 amplifications, and an Axin2 splice variant in juvenile angiofibromas

Juvenile angiofibromas (JAs) are benign fibro-vascular tumors occurring nearly exclusively in adolescent males. Even less is known about this rare tumor entity, alterations affecting the Wnt-pathway seem to play a pivotal role in tumor biology as activating CTNNB1 mutations have been detected. However, the knowledge of Wnt-pathway changes is still limited. Therefore, we aimed to determine in JAs further insight into Wnt/β-catenin pathway components. In our present study, genetic alterations of the Wnt-pathway members CTNNB1, APC, GSK3β, and Axin2 detected by metaphase comparative genomic hybridization (CGH) were shown to result in elevated transcript levels in the majority of JA samples compared to nasal mucosa stroma (p < 0.001, p = 0.001, p = 0.046, and p = 0.006, respectively). Additionally, amplifications of CTNNB1 were validated by fluorescence in situ hybridization (FISH) and genomic qPCR. Moreover, our mutation analysis detected already known mutations as well as, to the best of our knowledge, mutations and an interstitial deletion of CTNNB1 not described in JAs before. Additionally, a so far unknown transcribed Axin2 splice variant was found, but no further Axin2 mutations. Taken together, our current study supports the importance of aberrant Wnt-signaling as a common event in JAs, most likely by the observed genetic alterations driven by mutations, interstitial deletions but also amplifications of CTNNB1 contributing to the stabilization of β-catenin.

A generalized procedure for analyzing sustained and dynamic vocal fold vibrations from laryngeal high-speed videos using phonovibrograms

OBJECTIVE

This work presents a computer-based approach to analyze the two-dimensional vocal fold dynamics of endoscopic high-speed videos, and constitutes an extension and generalization of a previously proposed wavelet-based procedure. While most approaches aim for analyzing sustained phonation conditions, the proposed method allows for a clinically adequate analysis of both dynamic as well as sustained phonation paradigms.

MATERIALS AND METHODS

The analysis procedure is based on a spatio-temporal visualization technique, the phonovibrogram, that facilitates the documentation of the visible laryngeal dynamics. From the phonovibrogram, a low-dimensional set of features is computed using a principle component analysis strategy that quantifies the type of vibration patterns, irregularity, lateral symmetry and synchronicity, as a function of time. Two different test bench data sets are used to validate the approach: (I) 150 healthy and pathologic subjects examined during sustained phonation. (II) 20 healthy and pathologic subjects that were examined twice: during sustained phonation and a glissando from a low to a higher fundamental frequency. In order to assess the discriminative power of the extracted features, a Support Vector Machine is trained to distinguish between physiologic and pathologic vibrations. The results for sustained phonation sequences are compared to the previous approach. Finally, the classification performance of the stationary analyzing procedure is compared to the transient analysis of the glissando maneuver.

RESULTS

For the first test bench the proposed procedure outperformed the previous approach (proposed feature set: accuracy: 91.3%, sensitivity: 80%, specificity: 97%, previous approach: accuracy: 89.3%, sensitivity: 76%, specificity: 96%). Comparing the classification performance of the second test bench further corroborates that analyzing transient paradigms provides clear additional diagnostic value (glissando maneuver: accuracy: 90%, sensitivity: 100%, specificity: 80%, sustained phonation: accuracy: 75%, sensitivity: 80%, specificity: 70%).

CONCLUSIONS

The incorporation of parameters describing the temporal evolvement of vocal fold vibration clearly improves the automatic identification of pathologic vibration patterns. Furthermore, incorporating a dynamic phonation paradigm provides additional valuable information about the underlying laryngeal dynamics that cannot be derived from sustained conditions. The proposed generalized approach provides a better overall classification performance than the previous approach, and hence constitutes a new advantageous tool for an improved clinical diagnosis of voice disorders.

Novel modification of voice prosthesis

The undesired dilatation of the tracheooesophageal shunt after surgical implantation of voice prosthesis is a typical complication of this procedure. Temporary removal of the prosthesis and reinsertion after a short period of time is a first-line therapeutical option aiming shrinkage of the shunt. Failure of this measure generally is an indication of revision surgery. We present first experiences treating leakage problems with novel modified voice prosthesis without surgical intervention in specified cases. 11 patients (1 female, 10 male) aging between 51 and 71 years were presented with shunt leakage between 11/2008 and 11/2012 in the ENT-Department of the University Hospital of Homburg/Saar after a custom built voice prosthesis had been used initially successfully. A "Provox 2"(®) voice prosthesis was modified with two discs made of silicone each on the tracheal and oesophageal side and additionally reinforcing the diameter of the prosthesis by a silicone tube. The modified prosthesis was inserted in a retrograde way under general anesthesia, analogical to the approach used with the "Provox 1"(®)-prosthesis. The period of observation ranged between 12 and 48 months. As a measure of control swallowing of methylene blue was used. In all cases leakage suspended. Durability of the modified prosthesis ranged between 2 and 6 months. Neither the patients' complained about, nor did the physicians notice subjectively an impairment of the voice quality. Modifications of "Provox 2"(®)-prosthesis should be regarded in individual cases and constitute a reasonable alternative to revision surgery. A surgical approach is more intricate and costly, more taxing for the patient and susceptible to failure. We regard the necessity of general anesthesia for the insertion of the modified prosthesis as a disadvantage.

Mesenchymal-endothelial transition in juvenile angiofibroma?

CONCLUSION

Mesenchymal-endothelial transition is proposed for juvenile angiofibromas (JAs). Propranolol might be an interesting new medical option in JA treatment, as it reduces mesenchymal cell growth and decreases the number of CD31-positive cells in vitro.

OBJECTIVE

Juvenile angiofibromas (JAs) are rare fibro-vascular tumors affecting almost exclusively adolescent males. Based on morphological aspects of irregularly configured vascular spaces and clinical features, JAs have been proposed to represent a vascular malformation. In general, mesenchymal-endothelial transition has been noted as an important process in tumorigenesis as well as in embryonal development.

METHODS

The study analyzed effects of vascular endothelial growth factor (VEGF)/basic fibroblast growth factor (bFGF) and propranolol on endothelial differentiation (CD31+) of cultured JA cells and their expression of angiogenic growth factors using aortic ring assay and enzyme-linked immunosorbent assay.

RESULTS

Following VEGF/bFGF supplement to cultured mesenchymal cells, an average of 4.47% (± 2.35%) CD31-positive cells were found (p < 0.001). Propranolol addition reduced the number of CD31-positive cells and inhibited mesenchymal cell growth. The aortic ring assay and ELISA investigation indicated no increased angiogenic growth factor secretion from cultured JA mesenchymal cells.

Cell-type-specific tuning of Cav1.3 Ca(2+)-channels by a C-terminal automodulatory domain

Cav1.3 L-type Ca(2+)-channel function is regulated by a C-terminal automodulatory domain (CTM). It affects channel binding of calmodulin and thereby tunes channel activity by interfering with Ca(2+)- and voltage-dependent gating. Alternative splicing generates short C-terminal channel variants lacking the CTM resulting in enhanced Ca(2+)-dependent inactivation and stronger voltage-sensitivity upon heterologous expression. However, the role of this modulatory domain for channel function in its native environment is unkown. To determine its functional significance in vivo, we interrupted the CTM with a hemagglutinin tag in mutant mice (Cav1.3DCRD(HA/HA)). Using these mice we provide biochemical evidence for the existence of long (CTM-containing) and short (CTM-deficient) Cav1.3 α1-subunits in brain. The long (HA-labeled) Cav1.3 isoform was present in all ribbon synapses of cochlear inner hair cells. CTM-elimination impaired Ca(2+)-dependent inactivation of Ca(2+)-currents in hair cells but increased it in chromaffin cells, resulting in hyperpolarized resting potentials and reduced pacemaking. CTM disruption did not affect hearing thresholds. We show that the modulatory function of the CTM is affected by its native environment in different cells and thus occurs in a cell-type specific manner in vivo. It stabilizes gating properties of Cav1.3 channels required for normal electrical excitability.

Customized individual applicators for endocavitary brachytherapy in patients with cancers of the nasal cavity, sinonasal region and nasopharynx

Brachytherapy has become an established therapeutic regimen for primary, persistent, recurrent and metastatic tumour disease in the head and neck region. This study presents the authors' preliminary experience with intracavitary brachytherapy by means of an individual silicone applicator in the treatment of patients with nasal, sinonasal, orbital and nasopharyngeal cancer. Between January 2001 and January 2013, twenty patients with cancer of the nasal cavity, the paranasal sinuses and nasopharynx underwent surgery and intracavitary brachytherapy with the aid of an individually manufactured silicone applicator in the Department of Otolaryngology, Head and Neck Surgery and in the Department of Radiotherapy and Radiooncology at the Saarland University Medical Center of Homburg, Germany. The tumour was localized in the nasal cavity/paranasal sinuses (15) affecting the orbit twice and the nasopharynx (5). There were 14 patients with squamous cell carcinoma, 2 patients with mixed tumours and one patient with adenocarcinoma, adenoid cystic carcinoma, mucosal melanoma or plasmocytoma. The majority of the patients presented with advanced disease (T3 or T4 tumours). In 18/20 patients, brachytherapy was performed as a boost technique, in the remaining two solely because of a previous radiation series. All surgical interventions were performed endonasally. Three to six weeks after surgery, a cast of the nasal cavity was created under general anaesthesia. Subsequently, an individual brachytherapy silicon applicator with two to four plastic tubes was manufactured. The radiation therapy was applied using the Ir-192 high-dose-rate-afterloading method (total dose 10-20 Gy) in two to five sessions, additionally in 18/20 patients a percutaneous radiotherapy with a total dose of 30-60 Gy was applied. After a mean duration of follow-up of 2 years, 7/20 patients experienced a local progression, 5/19 a regional recurrence in the neck nodes and 4/19 distant metastases. The 2-year survival was 57.3 %. No serious complications were reported. The silicone applicator was well tolerated by all patients. Because of the complexity of the sinonasal anatomy with the finding of mainly advanced tumours, the presented individual silicone brachytherapy applicator has proven to be useful and meaningful for endocavitary brachytherapy of malignancies of the nasal cavities, paranasal sinuses and nasopharynx.

[Today's importance of ultrasound in ENT]

Since ultrasound has been established for diagnosis in ENT several new techniques have been introduced. But also ultrasonography has technically developed and thus has earned even more importance and indications. This was to be shown by this paper as well as the advantages and pitfalls. Ultrasound is quite useful in inflammatory, infectious and tumor pathology in order to make a better diagnosis or staging and to help the surgeon for punture or incision of a pathologic lesion (cytology, bacteriology, drainage). Especially in ENT oncology and post-treatment follow up ultrasound is a very precious technique. Ultrasound can be realized by the ENT specialist himself anywhere and at any time. It is a non aggressive, non invasive technique and its cost is relatively low. Unfortunately by itself it is not very performant to distinguish benign and malignant lesions. But its specificity can be considerably enhanced by combinating it with cytology (UGFNAB, ultrasound guided fine needle aspiration biopsy). Another important field of ultrasound is the examination of salivary glands.

Combination of p16(INK4a) /Ki67 immunocytology and HPV polymerase chain reaction for the noninvasive analysis of HPV involvement in head and neck cancer

BACKGROUND

High-risk human papillomavirus (HPV) infection has been identified as a relevant risk for the development of head and neck squamous cell carcinomas (HNSCCs). As HPV status has also gained a role as a prognostic and predictive biomarker for this entity, there is a growing demand for valid HPV testing in HNSCC patients

METHODS

Liquid-based cytological smears from 45 HNSCC and 20 control patients were collected and used for simultaneous immunocytochemical p16(INK4a) /Ki67 staining using a CINtec PLUS kit after the presence of tumor cells was verified in a Papanicolaou-stained slide. The same cytological suspension was used for the detection of HPV DNA by specific polymerase chain reaction (PCR).

RESULTS

Tumor cells were detected in the swab material of 44 HNSCC patients corresponding to a sensitivity of 98% (44 of 45). PCR analysis revealed the presence of HPV DNA in the cytological suspension of 13 patients (13 of 65, 20%) with simultaneous p16(INK4a) /Ki67 expression by the tumor cells in 11 of these HPV DNA-positive samples (11 of 13, 85%) - a staining pattern that is strongly associated with a carcinogenic HPV infection.

CONCLUSIONS

A simultaneous immunocytochemical detection of p16(INK4a) and Ki67 can reliably be performed on liquid-based cytological smears from HNSCC patients using a CINtec PLUS kit. In addition, the same cytological material can be used for the detection of HPV DNA by specific PCR. The combined results of both techniques enable better discrimination between latent and carcinogenic HPV infections as well as HPV-negative cases and thus can provide information on the prognosis of HNSCC patients and facilitate therapeutic decisions.

Cervical lymphadenopathy: study of 251 patients

Correct diagnosis of cervical lymphadenopathy is often a great challenge. The objective of this case study is to describe the distribution of the most common causes of unclear neck swellings presented in an ENT-Department and to evaluate the clinical history, examination and laboratory findings. In a retrospective study at the Department of Otorhinolaryngology, University Medical Center Homburg/Saar, 251 patients were enrolled with clinical and ultrasound signs of cervical lymphadenopathy as well as lymph node extirpation for histopathological evaluation. 127 patients (50.6 %) had a histological malignant finding. The distribution of the most common pathological conditions was as follows: Non-specific reactive hyperplasia n = 89 (35.5 %), metastases n = 86 (34.3 %), lymphoma n = 41 (16.3 %), granulomatous lesions n = 15 (6 %), abscess formations n = 5 (2 %), necrotic lymphadenitis and Castleman's disease one case of each, lymph node with normal architecture n = 7 (2.8 %), and neck masses mimicking lymphadenopathy n = 6 cases (2.4 %). The following factors identified by multivariate logistic regression were significantly associated to malignant lymphadenopathy: increasing age, generalized lymphadenopathy and history of malignant disorder, fixed neck masses and increasing diameter in ENT examination, bulky lesion, absence of hilus, blurred outer contour, protective role of the long form and decreasing Solbiati-index values by ultrasound B-Mode gray scale examination. Level II contained more benign lymphatic lesions, while the malignancy rate in level IV and V was enhanced. Laboratory parameters significantly associated to malignancies were CRP, LDH and thrombocytopenia. Patients with persisting cervical lymphadenopathy and over 3 weeks of antibiotic treatment should be considered for early biopsy, especially if some of the risk factors, pointed out in this study, are present.

Endonasal modification of the frontal sinus drainage type IIb according to Draf

The description of different endonasal drainage options (type I, II and III according to Draf) and their successful use in numerous patients has reached a milestone in frontal sinus surgery. We herein describe a modification of an endonasal frontal sinus drainage type IIb with the additional removal of the lower part of the frontal sinus septum without opening the frontal recess of the other side and without resection of the nasal septum. The modified endonasal endoscopic frontal sinus drainage type IIb was performed on 9 patients at the Department of Otorhinolaryngology, University Medical Center, Homburg/Saar between 02/2011 and 6/2013 after having gained patients' consent. Follow-ups with endoscopic examination were performed after 6, 12 and 24 months (median follow-up: 14 months). Endonasal endoscopic opening of the frontal sinus was achieved in all patients. Endoscopic examination 6, 12 and 24 months after surgery revealed patent frontal sinus drainage in 8 patients. The frontal sinus drainage could not be visualized endoscopically in one patient who was free of symptoms for 24 months and where a ventilated frontal sinus was proven radiologically by computed tomography. The study demonstrates the option to additionally remove the lower part of the inter-frontal septum with a frontal sinus drainage type IIb. As the number of patients treated by this modified frontal sinus type IIb drainage is limited, further investigations are needed to define the value of a modified frontal sinus drainage type IIb.

A novel multipurpose mini-endoscope for frontal sinus endoscopy "sinus view"

Endoscopic frontal sinus surgery has been proven to enable the treatment of most frontal sinus pathologies but may be challenging for the surgeon in regard to the variable frontal sinus anatomy. Frontal sinus drainage identification and frontal sinus visualization are an essential part of successful frontal sinus surgery. We demonstrate a novel modular mini-endoscopic system for frontal sinus surgery. Fifty-two patients (37 male, 15 female) with a chronic rhino-sinusitis were enrolled. In this study, all patients were subjected to standard endonasal endoscopic sinus surgery with use of the fibre optic endoscope "Sinus View" (1.1 mm diameter, 10,000 pixels, irrigation channel and additional working channel) accessing the frontal sinus. A frontal sinus drainage type I in 38 cases, a frontal sinus drainage type IIa in 9 cases and a frontal sinus drainage type IIb in 5 cases according to Draf were performed. The modular mini-endoscopic system "Sinus view" was used to identify frontal sinus drainage in ten patients before ethmoidectomy and in the remaining patients (N = 42) after ethmoidectomy. Visualization of the frontal sinus drainage or the frontal sinus itself was easily carried out after irrigation. A clear identification of the frontal sinus by illumination was achieved in all cases. In addition the working channel of the endoscope was successfully used to perform visualized balloon dilatation at the frontal sinus drainage or for biopsy. The endonasal visualization of the frontal sinus drainage and frontal sinus itself is facilitated by also using a modular mini-endoscope with the option to use the working channel of the endoscope for biopsy or balloon dilatation.

Preliminary analysis of different microRNA expression levels in juvenile angiofibromas

Juvenile angiofibroma (JA) is a rare fibrovascular tumor affecting, almost exclusively, adolescent males. The finding of frequent β-catenin-mutations in JAs emphasized the significance of the Wnt-signaling pathway in tumor pathogenesis. In the last decade, microRNAs (miRNAs or miRs) have been found to be involved in cancer pathogenesis by post-transcriptional regulation of gene expression and have not been analyzed in JAs thus far. In the present study, the expression of 4 miRNAs (hsa-let-7d, hsa-miR-98, hsa-miR-125a-5p and hsa-miR-218) was analyzed in 13 JAs and 3 deepithelized inferior nasal turbinates that were used as control tissue. The miRNA expression of hsa-let-7d (P=0.158) and hsa-miR-98 (P=0.069) was not statistically different between the two tissue types, however, a significant decrease in expression was observed for hsa-miR-125a-5p (P=0.037) and hsa-miR-218 (P=0.009) in JAs compared to inferior nasal turbinates. As downregulation of miRNA 218 has been recently shown to result in stabilization and nuclear accumulation of β-catenin, the present data indicates further evidence for the importance of the Wnt-signaling pathway in JAs.

[A new implant system for orbital prosthetic rehabilitation: "epiplating mono"]

A New Implant System for Orbital Prosthetic Rehabilitation: "Epiplating Mono" Prosthetic or episthetic rehabilitation of ear, eye and nose are currently most common performed using magnetic fixation. While at the beginning single implants have been used, now-a-days a more extended approach with plate fixation are recommended to enhance the stability of the anchored magnets. A newly designed implant system epiplating mono is presented that combines the structure of a single implant with additional fixation elements. In a pilot study this new implant system was used in 4 patients for prosthetic orbital rehabilitation. Further experiences with this new implant system are required necessitating long-term experiences of implant stability to define the value of the presented epiplating mono system for prosthetic rehabilitation.

Quantifying spatiotemporal properties of vocal fold dynamics based on a multiscale analysis of phonovibrograms

In order to objectively assess the laryngeal vibratory behavior, endoscopic high-speed cameras capture several thousand frames per second of the vocal folds during phonation. However, judging all inherent clinically relevant features is a challenging task and requires well-founded expert knowledge. In this study, an automated wavelet-based analysis of laryngeal high-speed videos based on phonovibrograms is presented. The phonovibrogram is an image representation of the spatiotemporal pattern of vocal fold vibration and constitutes the basis for a computer-based analysis of laryngeal dynamics. The features extracted from the wavelet transform are shown to be closely related to a basic set of video-based measurements categorized by the European Laryngological Society for a subjective assessment of pathologic voices. The wavelet-based analysis further offers information about irregularity and lateral asymmetry and asynchrony. It is demonstrated in healthy and pathologic subjects as well as for a surgical group that was examined before and after the removal of a vocal fold polyp. The features were found to not only classify glottal closure characteristics but also quantify the impact of pathologies on the vibratory behavior. The interpretability and the discriminative power of the proposed feature set show promising relevance for a computer-assisted diagnosis and classification of voice disorders.

Expression of sex hormone receptors in juvenile angiofibromas and antiproliferative effects of receptor modulators

BACKGROUND

Predilection of juvenile angiofibromas in adolescent boys has prompted the hypothesis of hormone-dependent tumor growth. However, knowledge on expression and function of sex hormone receptors in juvenile angiofibromas is still sparse and inconsistent.

METHODS

Transcript and protein expression of sex hormone receptors in juvenile angiofibromas was studied by quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) and immunohistology/fluorescence. A bromodeoxyuridine assay was used to assess the antiproliferative effects of flutamide (androgen receptor antagonist) and tamoxifen (estrogen receptor modulator).

RESULTS

Significantly increased transcript levels were observed for androgen receptor, estrogen receptor α, follicle-stimulating hormone receptor, and luteinizing hormone receptor in juvenile angiofibromas versus the stroma of nasal mucosa. Estrogen receptor β and progesterone receptor mRNA levels were low and similar for both tissues. Estrogen receptor α protein was detected in juvenile angiofibroma tumors and mesenchymal cell lines. Flutamide and tamoxifen inhibited proliferation of cultured juvenile angiofibroma mesenchymal cells.

CONCLUSION

These findings contribute to the understanding of juvenile angiofibroma pathophysiology and offer novel therapeutic options.

Optimal invasive key-hole neurosurgery with a miniaturized 3D chip on the tip: Microendoscopic device

Objective:

The goal of the performed study was to evaluate the possibility of a three-dimensional endoscope to become a combined microscope-endoscope device in one. We analyzed the ergonomy of the device, the implementation into the surgical workflow, the image quality, and the future perspectives such devices could have for the next generation of neurosurgeons.

Materials and Methods:

Within 6 months, 22 patients (10 male, 12 female, 20-65 age) underwent surgery in neuroaxis using the new 3D-microendoscope (ME). The new 3D-ME has (a) the ability to visualize the surgical field from out- to inside with all advantages offered by a microscope, and in the same moment, (b) its design is like a small diameter endoscope that allows stereoscopic views extracorporal, intracorporal, and panoramic “para-side” of the lesion.

Results:

In general, transcranial 3D-“microendoscopy” was performed in all patients with high-resolution 3D quality. No severe complications were observed intra- or postoperatively. With the addition of depth perception, the anatomic structures were well seen and observed.

Conclusion:

The 3D-microendoscopy is a very promising surgical concept associated with new technological developments. The surgeon is able to switch to a modern visualization instrument reaching the most optimal surgical approach without compromising safety, effectiveness, and visual information.

Surgery of the ear and the lateral skull base: pitfalls and complications

Surgery of the ear and the lateral skull base is a fascinating, yet challenging field in otorhinolaryngology. A thorough knowledge of the associated complications and pitfalls is indispensable for the surgeon, not only to provide the best possible care to his patients, but also to further improve his surgical skills. Following a summary about general aspects in pre-, intra-and postoperative care of patients with disorders of the ear/lateral skull base, this article covers the most common pitfalls and complications in stapes surgery, cochlear implantation and surgery of vestibular schwannomas and jugulotympanal paragangliomas. Based on these exemplary procedures, basic "dos and don'ts" of skull base surgery are explained, which the reader can easily transfer to other disorders. Special emphasis is laid on functional aspects, such as hearing, balance and facial nerve function. Furthermore, the topics of infection, bleeding, skull base defects, quality of life and indication for revision surgery are discussed. An open communication about complications and pitfalls in ear/lateral skull base surgery among surgeons is a prerequisite for the further advancement of this fascinating field in ENT surgery. This article is meant to be a contribution to this process.