Andrew Van Hasselt

Intranasal anatomy of the nasolacrimal sac in endoscopic dacryocystorhinostomy

Intranasal surface anatomy is fundamental to the technique of endoscopic dacryocystorhinostomy. In the current literature the lacrimal sac is described as being situated anterior to the anterior end of the middle turbinate with between 0% and 20% of the sac above the insertion of the middle turbinate on the lateral nasal wall (the axilla of the middle turbinate). The aim of this study was to use CT dacryocystograms (DCGs) and CT scans to establish the relationship of the lacrimal sac to the lateral nasal wall. Forty-seven individual lacrimal sacs were measured in relation to the common canaliculus, and 76 were measured in relation to the insertion of the middle turbinate. Measurements taken from the long axis of the sac showed the mean height of the sac above the middle turbinate insertion was 8.8 mm (SD = 0.2, 95% Cl = 1.3) and below it was 4.1 mm (SD = 2.3, 95% Cl = 1.1). The average measurement of the sac above the common canaliculus on CT DCGs was 5.3 mm (SD = 1.7, 95% Cl = 0.56), whereas the average measurement below the common canaliculus was 7.7 mm (SD = 2, 95% Cl = 1.3) (n = 47 CT DCGs). The findings in this study show that a major portion of the sac is located above the insertion of the anterior end of the middle turbinate and, in addition, that a significant part of the sac lies above the entry point of the common canaliculus. Knowledge of these findings can ensure that the sac is adequately exposed during dacryocystorhinostomy by removal of sufficient bone and mucosa above the anterior insertion of the middle turbinate. (Otolaryngol Head Neck Surg 2000;123:307-10.)

The tumor suppressor UCHL1 forms a complex with p53/MDM2/ARF to promote p53 signaling and is frequently silenced in nasopharyngeal carcinoma.

Purpose: Nasopharyngeal carcinoma is prevalent in southern China and Southeast Asia, with distinct geographic and ethnic distribution. One candidate susceptibility locus has been identified at 4p11-14, with the associated candidate gene(s) not identified yet. This study investigated the role of ubiquitin carboxyl-terminal hydrolase L1 (UCHL1) in nasopharyngeal carcinoma pathogenesis. Experimental Design: UCHL1 expression and methylation were examined in nasopharyngeal carcinoma. Furthermore, the mechanism of its tumor-suppressive function was elucidated in nasopharyngeal carcinoma cells. Results: Through genomewide expression profiling, we identified UCHL1, a 4p14 gene normally expressed in normal upper respiratory tract tissues, being silenced in all nasopharyngeal carcinoma cell lines. Its silencing is mediated by CpG methylation because UCHL1 promoter methylation was detected in all silenced cell lines, and pharmacologic demethylation reactivated UCHL1 expression along with concomitant promoter demethylation. UCHL1 methylation was also frequently detected in primary tumors but only weakly detected in few normal nasopharyngeal tissues, indicating that the methylation-mediated silencing of UCHL1 is important in nasopharyngeal carcinoma pathogenesis. Ectopic UCHL1 expression dramatically inhibited the growth of nasopharyngeal carcinoma cells through promoting tumor cell apoptosis. We further found that UCHL1 formed a complex with p53/p14ARF/Mdm2 p53 binding protein homolog (mouse), MDM2 and activated the p53 signaling pathway. UCHL1 expression extended p53 and p14ARF protein half-life and shortened MDM2 protein half-life. Conclusions: These results indicate that UCHL1 could deubiquitinate p53 and p14ARF and ubiquitinate MDM2 for p53 stabilization to promote p53 signaling, thus involved in nasopharyngeal carcinoma pathogenesis, whereas it is frequently silenced in this tumor. Clin Cancer Res; 16(11); 2949–58. ©2010 AACR.

Endoscopic removal of juvenile angiofibromas.

BACKGROUND Angiofibromas have traditionally been removed through open procedures. All tumors in this consecutive series of patients were removed endoscopically. SETTING Tertiary care hospital. MATERIALS AND METHODS Seven consecutive patients presenting with an angiofibroma between 1994 and 2000 were included in the study. Tumor size varied with 1 stage 1, 2 stage IIa, 3 stage IIb, and 1 stage IIC according to the Radkowski et al classification. The surgical technique is presented. RESULTS After an average of 3.75 years (SD, 1.9 years), there have been no tumor recurrences. CONCLUSION Endoscopic removal of angiofibromas in the nasal cavity, with extension into the sinuses and pterygopalatine fossa and with limited extension into the infratemporal fossa, can be removed endoscopically with a good success rate.

OPCML is a broad tumor suppressor for multiple carcinomas and lymphomas with frequently epigenetic inactivation.

Background Identification of tumor suppressor genes (TSGs) silenced by CpG methylation uncovers the molecular mechanism of tumorigenesis and potential tumor biomarkers. Loss of heterozygosity at 11q25 is common in multiple tumors including nasopharyngeal carcinoma (NPC). OPCML, located at 11q25, is one of the downregulated genes we identified through digital expression subtraction. Methodology/Principal Findings Semi-quantitative RT-PCR showed frequent OPCML silencing in NPC and other common tumors, with no homozygous deletion detected by multiplex differential DNA-PCR. Instead, promoter methylation of OPCML was frequently detected in multiple carcinoma cell lines (nasopharyngeal, esophageal, lung, gastric, colon, liver, breast, cervix, prostate), lymphoma cell lines (non-Hodgkin and Hodgkin lymphoma, nasal NK/T-cell lymphoma) and primary tumors, but not in any non-tumor cell line and seldom weakly methylated in normal epithelial tissues. Pharmacological and genetic demethylation restored OPCML expression, indicating a direct epigenetic silencing. We further found that OPCML is stress-responsive, but this response is epigenetically impaired when its promoter becomes methylated. Ecotopic expression of OPCML led to significant inhibition of both anchorage-dependent and -independent growth of carcinoma cells with endogenous silencing. Conclusions/Significance Thus, through functional epigenetics, we identified OPCML as a broad tumor suppressor, which is frequently inactivated by methylation in multiple malignancies.

The tumor suppressor Wnt inhibitory factor 1 is frequently methylated in nasopharyngeal and esophageal carcinomas

Aberrant activation of the wingless-type- (Wnt)-signaling pathway is common in many cancers including nasopharyngeal (NPC) and esophageal squamous cell (ESCC) carcinomas, both prevalent in Southern China and Southeast Asia. However, the molecular mechanism leading to this abnormality is still obscure. Wnt inhibitory factor-1 (WIF1) is a secreted antagonist of the Wnt pathway, and is recently shown to be inactivated by epigenetic mechanism in some tumors. Here, we examined whether WIF1 is also inactivated epigenetically in NPC and ESCC. With semiquantitative reverse transcription-PCR and methylation-specific PCR, we detected WIF1 downregulation or silencing in 6/6 of NPC and 12/19 of ESCC cell lines, which is well correlated with its methylation status. Methylation was further confirmed by high-resolution bisulfite genomic sequencing. Methylation was also frequently observed in a large collection of primary tumors of NPC (85%, 55/65) and ESCC (27%, 25/92), with WIF1 expressed and unmethylated in normal NPC and esophageal cell lines and normal tissues. Treatment of 5-aza-2′-deoxycytidine demethylated WIF1 and induced its expression in NPC and ESCC cell lines, highlighting a direct role of epigenetic inactivation. Ectopic expression of WIF1 in NPC and ESCC tumor cells resulted in significant inhibition of tumor cell colony formation, similar to TP53, and also significant downregulation of β-catenin protein level in NPC cells. Thus, WIF1 functions as a tumor suppressor for both NPC and ESCC through suppressing the Wnt-signaling pathway, but is frequently silenced by epigenetic mechanism in a tumor-specific way. Our study indicates that epigenetic inactivation of WIF1 contributes to the aberrant activation of Wnt pathway and is involved in the pathogenesis of both tumors. WIF1 methylation could also serve as a specific biomarker for these tumors.

Early detection of nasopharyngeal carcinoma by plasma Epstein-Barr virus DNA analysis in a surveillance program

Nasopharyngeal carcinoma (NPC) is prevalent in Southeast Asia. Over the last decade, plasma Epstein‐Barr virus (EBV) DNA has been developed as a tumor marker for NPC. In this study, the authors investigated whether plasma EBV DNA analysis is useful for NPC surveillance.

Analysis of Plasma Epstein–Barr Virus DNA to Screen for Nasopharyngeal Cancer

BACKGROUND Circulating cell‐free Epstein–Barr virus (EBV) DNA is a biomarker for nasopharyngeal carcinoma. We conducted a prospective study to investigate whether EBV DNA in plasma samples would be useful to screen for early nasopharyngeal carcinoma in asymptomatic persons. METHODS We analyzed EBV DNA in plasma specimens to screen participants who did not have symptoms of nasopharyngeal carcinoma. Participants with initially positive results were retested approximately 4 weeks later, and those with persistently positive EBV DNA in plasma underwent nasal endoscopic examination and magnetic resonance imaging (MRI). RESULTS A total of 20,174 participants underwent screening. EBV DNA was detectable in plasma samples obtained from 1112 participants (5.5%), and 309 (1.5% of all patients and 27.8% of those who initially tested positive) had persistently positive results on the repeated sample. Among these 309 participants, 300 underwent endoscopic examination, and 275 underwent both endoscopic examination and MRI; of these participants, 34 had nasopharyngeal carcinoma. A significantly higher proportion of participants with nasopharyngeal carcinoma that was identified by screening had stage I or II disease than in a historical cohort (71% vs. 20%, P<0.001 by the chi‐square test) and had superior 3‐year progression‐free survival (97% vs. 70%; hazard ratio, 0.10; 95% confidence interval, 0.05 to 0.18). Nine participants declined to undergo further testing, and 1 of them presented with advanced nasopharyngeal carcinoma 32 months after enrollment. Nasopharyngeal carcinoma developed in only 1 participant with negative EBV DNA in plasma samples within 1 year after testing. The sensitivity and specificity of EBV DNA in plasma samples in screening for nasopharyngeal carcinoma were 97.1% and 98.6%, respectively. CONCLUSIONS Analysis of EBV DNA in plasma samples was useful in screening for early asymptomatic nasopharyngeal carcinoma. Nasopharyngeal carcinoma was detected significantly earlier and outcomes were better in participants who were identified by screening than in those in a historical cohort. (Funded by the Kadoorie Charitable Foundation and the Research Grants Council of the Hong Kong government; ClinicalTrials.gov number, NCT02063399.)

The Nuclear Localization of NFκB and p53 Is Positively Correlated with HPV16 E7 Level in Laryngeal Squamous Cell Carcinoma

The interaction between the HPV (human papilloma virus) 16 E7 and other cell growth factors, such as p53 and NFκB in laryngeal cancer is not clearly understood. The aim of this study was to examine the expression of these three proteins in tumor and non-tumor laryngeal tissues from patients with laryngeal squamous cell carcinoma. These three proteins were dominantly expressed in the nucleus and their levels were higher in the tumor tissue than in the non-tumor tissue, although the comparison between the tumor and non-tumor tissues of p53 staining did not reach significance. The intensity of the nuclear stain of E7 and p53 was stronger than that of p65, a subunit of NFκB. Correlation analysis revealed that there was a positive relationship between the level of HPV16 E7 and the expression of p65. The correlation between E7 and p53 was also significant, although to a lesser degree. The finding of nuclear localization of p65 suggests that NFκB is constantly activated in the laryngeal cancer cells, whereas the sequestration of p53 in the nucleus may represent a mutated form of p53, which is probably inactivated by HPV16 oncoproteins. In conclusion, this study suggests that the nuclear localization of NFκB and p53 may play a role in the development of human laryngeal squamous cell carcinoma infected with HPV16.

Clinical Performance of a New Magnetic Bone Conduction Hearing Implant System: Results from a Prospective, Multicenter, Clinical Investigation

Objective The aim of the investigation was to prospectively evaluate, in a multicenter setting, the clinical performance of a new magnetic bone conduction hearing implant system. Methods The test device was the Cochlear Baha Attract System (Cochlear Bone Anchored Solutions AB, Mölnlycke, Sweden). Instead of the skin-penetrating abutment of traditional bone conduction hearing implants, the test device uses an implantable and an external magnet to transmit sound from the sound processor (SP) through intact skin to the skull bone. Twenty-seven adult patients with a conductive or mild mixed hearing loss or single-sided sensorineural deafness were included in the clinical investigation across four investigational sites. The patients were followed for 9 months after implantation. The study evaluated efficacy in terms of hearing performance compared with unaided hearing and with hearing with the SP on a softband. Patient benefit, soft tissue status, device retention, and safety parameters were monitored continuously throughout the investigation. Results Surgery and healing was uneventful. Statistically significant improvements in audibility and speech understanding in noise and quiet were recorded for the test device compared with preoperative unaided hearing. Speech recognition was similar or better than tests performed with the same SP on a softband. Good soft tissue outcomes were reported, without major pressure-related complications. At the end of the investigation, all patients continued to use and benefit from the device. Conclusion The test device provides good hearing performance in patients with a conductive hearing loss or single-sided sensorineural deafness, with good wearing comfort and minimal soft tissue complications.

Early Swallowing Problems in a Cohort of Patients With Nasopharyngeal Carcinoma: Symptomatology and Videofluoroscopic Findings

Objective: To study the incidence and the degree of swallowing dysfunction in patients with nasopharyngeal carcinoma (NPC) who underwent radiation therapy treatment.