Protection of laryngeal mucosa and function in laryngeal burns by heat absorption of perilaryngeal tissue

OBJECTIVE

The laryngeal tissue carries most of the heat during inhalation injury. This study aims to explore the heat transfer process and the severity of injury inside laryngeal tissue by horizontally studying the temperature rise process at various anatomical layers of the larynx and observing the thermal damage in various parts of the upper respiratory tract.

METHODS

The 12 healthy adult beagles were randomly divided into four groups, and inhaled room temperature air (control group), dry hot air of 80 °C (group I), 160 °C (group II), and 320 °C (group III) for 20 min, respectively. The temperature changes of the glottic mucosal surface, the inner surface of the thyroid cartilage, the external surface of the thyroid cartilage, and subcutaneous tissue were measured every minute. All animals were immediately sacrificed after injury, and pathological changes in various parts of laryngeal tissue were observed and evaluated under a microscope.

RESULTS

After inhaling hot air of 80 °C, 160 °C and 320 °C, the increase of laryngeal temperature in each group was ΔT = 3.57 ± 0.25 °C, 7.83 ± 0.15 °C, 11.93 ± 0.21 °C. The tissue temperature was approximately uniformly distributed, and the difference was not statistically significant. The average laryngeal temperature-time curve showed that the laryngeal tissue temperature in group I and group II showed a trend of "first decrease and then increase", except that the temperature of group III directly increased with time. The prominent pathological changes after thermal burns mainly concluded necrosis of epithelial cells, loss of the mucosal layer, atrophy of submucosal glands, vasodilatation, erythrocytes exudation, and degeneration of chondrocytes. Mild degeneration of cartilage and muscle layers was also observed in mild thermal injury. Pathological scores indicated that the pathological severity of laryngeal burns increased significantly with the increase of temperature, and all layers of laryngeal tissue were seriously damaged by 320 °C hot air.

CONCLUSIONS

The high efficiency of tissue heat conduction enabled the larynx to quickly transfer heat to the laryngeal periphery, and the heat-bearing capacity of perilaryngeal tissue has a certain degree of protective effect on laryngeal mucosa and function in mild to moderate inhalation injury. The laryngeal temperature distribution was in accordance with the pathological severity, and the pathological changes of laryngeal burns provided a theoretical basis for the early clinical manifestations and treatment of inhalation injury.

Mainstream Cigarette Smoke Impacts the Mouse Vocal Fold Epithelium and Mucus Barrier

OBJECTIVES/HYPOTHESIS

Cigarette smoke (CS) is a primary risk factor for the development of numerous benign and malignant laryngeal diseases. The epithelium and mucus lining the vocal folds (VF) are the first barriers against CS. The primary objective of this study was to investigate epithelial and mucus barrier changes in the mouse laryngeal mucosa upon exposure to subacute CS. The secondary objective was to compare mucus barrier changes in mice and human smokers and nonsmokers. Study Design Animal model.

METHODS

Mice were exposed to CS for 4 weeks for 4 hours (N = 12, high dose [HD]) or 1 hour (N = 12, low dose [LD]) per day. Air-exposed mice were used as a control group (N = 10). Larynges were harvested and VF epithelial barrier integrity was evaluated including cellular proliferation and expression of cell junctions. We also investigated mucus production by examining mucus cell area and mucin expression in mice and human smokers and nonsmokers.

RESULTS

HD CS increased VF epithelial cellular proliferation but did not alter the expression of cell junctions. HD CS also induced hypertrophy of the mucus-producing submucosal glands. However, only LD CS increased MUC5AC gene expression. MUC5AC staining appeared elevated in laryngeal specimens from smokers, but this was not significant as compared to nonsmokers.

CONCLUSIONS

These findings help us identify potential adaptive mechanisms to CS exposure as well as set the foundation for further study of key aspects of epithelial and mucus barrier integrity that may be implicated in laryngeal disease development following prolonged smoking.

LEVEL OF EVIDENCE

NA Laryngoscope, 131:2530-2539, 2021.

Probe-based confocal laser endomicroscopy for diagnosis of nasopharyngeal carcinoma in vivo

OBJECTIVES/HYPOTHESIS

Probe-based confocal laser endomicroscopy (pCLE) is a novel technique allowing real-time evaluation of the histological features of tissues in vivo at the cellular level. This study aimed to evaluate the feasibility of using pCLE in the diagnosis of nasopharyngeal carcinoma (NPC).

STUDY DESIGN

Feasibility study.

METHODS

In this study, the pCLE images of the lesions, as well as the surrounding or contralateral normal mucosa of the lesions, were acquired in vivo from each patient after intravenous injecting of 2.5 mL fluorescein. Biopsy specimens were collected at the imaged sites followed by a histopathological diagnosis by the pathologists, which was used as the gold standard. The pCLE images were compared to histopathological diagnosis of visualized sites by using sensitivity, specificity, negative predictive value (NPV), and positive predictive value (PPV).

RESULTS

Diagnoses based on pCLE images correlated well with the gold standard diagnoses based on tissue histology. The overall sensitivity, specificity, PPV, and NPV for diagnosis of carcinoma versus nondysplasia were 93.8% (67.7%-99.7%), 90.5% (68.2%-98.3%), 88.2% (62.3%-97.9%), and 95.0% (73.1%-99.7%), respectively, and the four indices for pCLE diagnosis of dysplasia versus nondysplasia were 60.0% (17.0%-92.7%), 80.9% (57.4%-93.7%), 42.9% (11.8%-79.8%), and 89.5% (65.5%-98.2%), respectively. The overall sensitivity for diagnosis of carcinoma versus dysplasia was 93.8% (67.7%-99.7%), specificity was 40% (7.3%-83.0%), PPV was 83.3% (57.7%-95.6%), and the NPV was 66.7% (12.5%-98.2%).

CONCLUSIONS

CLE is a suitable and valid method for otolaryngologists to diagnose of NPC in vivo.

LEVEL OF EVIDENCE

NA Laryngoscope, 129:897-902, 2019.

Primary Mucosal Malignant Melanoma of the Larynx: Case Report and Review of the Literature

We report a case of primary melanoma of the larynx in a patient who died of disseminated disease 13 months later. It is a rare malignant tumor in the head and neck, accounting for 0.4-10% of all melanomas of this site. Histologically, the presence of in situ changes within the laryngeal mucosa strongly supports our diagnosis of primary melanoma of the larynx.

Immunolocalization of CD163+ Tumor-Associated Macrophages and Symmetric Proliferation of Ki-67 as Biomarkers to Differentiate New Different Grades of Laryngeal Dysplasia

OBJECTIVES

To evaluate CD163+ tumor-associated macrophages (TAMs), Ki-67, and cyclin D1 to differentiate laryngeal dysplasia in the 2017 World Health Organization classification.

METHODS

Immunohistochemistry for CD163, Ki-67, and cyclin D1 was performed using paraffin-embedded specimens. CD163+ TAMs infiltrating the epithelium were estimated. Ki-67 and cyclin D1 were evaluated in four parts of the epithelium-basal, parabasal, middle third, and upper third layers.

RESULTS

In total, 133 specimens were analyzed, including low-grade dysplasia (n = 31), high-grade dysplasia (n = 49), carcinoma in situ (n = 23), and normal mucosa (n = 30). CD163+ TAMs infiltrating the epithelium were significantly higher in high-grade dysplasia than in low-grade dysplasia. In the basal layer, Ki-67+ and cyclin D1+ cells were overexpressed in high-grade dysplasia (P < .0001). The area under the curve was 0.958 for Ki-67 and 0.909 for CD163+ TAMs (P < .0001).

CONCLUSIONS

CD163+ TAMs infiltrating the epithelium and Ki-67 overexpression in the basal layer may serve as biomarkers to differentiate low-grade dysplasia from high-grade dysplasia of the larynx. A symmetric proliferative pattern was observed during laryngeal carcinogenesis following Ki-67 overexpression.

In vivo measurement of vocal fold surface resistance

OBJECTIVES/HYPOTHESIS

A custom-designed probe was developed to measure vocal fold surface resistance in vivo. The purpose of this study was to demonstrate proof of concept of using vocal fold surface resistance as a proxy of functional tissue integrity after acute phonotrauma using an animal model.

STUDY DESIGN

Prospective animal study.

METHODS

New Zealand White breeder rabbits received 120 minutes of airflow without vocal fold approximation (control) or 120 minutes of raised intensity phonation (experimental). The probe was inserted via laryngoscope and placed on the left vocal fold under endoscopic visualization. Vocal fold surface resistance of the middle one-third of the vocal fold was measured after 0 (baseline), 60, and 120 minutes of phonation. After the phonation procedure, the larynx was harvested and prepared for transmission electron microscopy.

RESULTS

In the control group, vocal fold surface resistance values remained stable across time points. In the experimental group, surface resistance (X% ± Y% relative to baseline) was significantly decreased after 120 minutes of raised intensity phonation. This was associated with structural changes using transmission electron microscopy, which revealed damage to the vocal fold epithelium after phonotrauma, including disruption of the epithelium and basement membrane, dilated paracellular spaces, and alterations to epithelial microprojections. In contrast, control vocal fold specimens showed well-preserved stratified squamous epithelia.

CONCLUSIONS

These data demonstrate the feasibility of measuring vocal fold surface resistance in vivo as a means of evaluating functional vocal fold epithelial barrier integrity. Device prototypes are in development for additional testing, validation, and for clinical applications in laryngology.

LEVEL OF EVIDENCE

NA Laryngoscope, 127:E364-E370, 2017.

Rare primary mucosal melanoma of the larynx

Few cases of primary mucosal melanoma of the larynx have been documented in the literature, so only a limited amount of data exists regarding its diagnosis and treatment. The prognosis is poor, as patients often present at a late stage with regional or distant metastases. We describe the case of a 66-year-old man who presented with hoarseness and dysphagia. Laryngoscopy identified a dark discoloration of the supraglottic larynx and incomplete mobility of the right vocal fold; an excisional biopsy confirmed the diagnosis. We discuss the epidemiology, clinical features, diagnosis, interpretation of imaging findings, and management of this rare malignant melanoma.

Features of oral, pharyngeal, and laryngeal lesions in bullous pemphigoid

Bullous pemphigoid is an autoimmune bullous disease characterized by skin lesions, with or without oral lesions. The occurrence of pharyngolaryngeal lesions is very rare in affected patients. We conducted a study to investigate the characteristics of oral and pharyngolaryngeal lesions in bullous pemphigoid. Our study population was made up of 6 consecutively presenting outpatients-2 men and 4 women, aged 40 to 83 years (mean: 68.2)-who had been referred to our department over an 11-year period. Presenting symptoms included sore throat in all 6 patients and oral pain in 3. The sites of mucosal lesions included the soft palate, epiglottis, gingiva, hypopharynx, tongue, nasal cavity, and buccal mucosa. These lesions appeared as erosions, erosions with white coating, erythematous patches, and/or blisters. Mucosal lesions preceded skin lesions in 2 patients, appeared after skin lesions in 1 patient, and appeared simultaneously with skin lesions in 3 patients. We conclude that bullous pemphigoid sometimes involves the mucosa, such as that of the laryngopharynx and the oral cavity, and it can manifest as skin lesions. In the differential diagnosis of refractory pharyngolaryngeal lesions, bullous pemphigoid should be considered.

Histopathologic Changes in Laryngeal Mucosa of Extremely Low-Birth Weight Infants after Endotracheal Intubation

Objectives:

Advances in medicine have improved the survival of infants with increasingly lower birth weights. The histopathologic changes of intubation-related laryngeal injury in extremely low-birth weight infants (less than 1,000 g) have not been well known. We examined histopathologic changes in infant larynges, including extremely low-birth weight infants, after endotracheal intubation.

Methods:

Forty-four infants, including 21 extremely low-birth weight infants, who had been intubated for periods ranging from 10 minutes to 138 days, were examined in a whole organ serial section study.

Results:

As the duration of intubation increased, the ulceration was found to be larger and deeper. The injury at the subglottis and posterior glottis was greater than that at other portions. The perichondrium of the cartilage was exposed in many cases intubated longer than 8 days. Repaired epithelium that was composed of squamous epithelium was present in 6 of 7 larynges that had been intubated more than 20 days, indicating that not only injury but also the healing process occurred during long intubation. There were no obvious relationships between the degree of intubation injury and the birth weight of the infants.

Conclusions:

Prolonged intubation is better tolerated by infants than adults. The intubation-related laryngeal injuries of extremely low-birth weight infants were histopathologically the same as those of infants of other birth weights.

Bile-Induced Laryngitis: Is There a Basis in Evidence?

Most agree that bile reflux occurs with regularity in an otherwise healthy population and that biliary and acid reflux may play a synergistic role in damaging esophageal mucosa. But to what extent is laryngeal mucosa at risk? We constructed a saline-controlled rat model (n = 40) in which active component solutions of bile — taurocholic acid and chenodeoxycholic acid — were applied to intact laryngeal mucosa at various pH levels. Histologic sampling of the laryngeal mucosa allowed inflammation scores to be generated by a pathologist blinded to the solutions used. Both taurocholic acid at acid pH and chenodeoxycholic acid at basic pH preferentially induced statistically greater inflammation scores than did the saline control, approaching or exceeding inflammation scores attributed to hydrochloric acid at pH 1.2. These observations may clarify reasons for failure to uniformly control laryngeal injury by adequate suppression of gastric acid alone and may further justify alternative methods of laryngeal protection in patients refractory to adequate acid control.

Noninvasive Measurement of Ablation Crater Size and Thermal Injury after CO2 Laser in the Vocal Cord with Optical Coherence Tomography

OBJECTIVES: To characterize tissue destruction after CO2 laser-ablation of the vocal cords with the use of optical coherence tomography (OCT).

STUDY DESIGN AND SETTING: OCT was used to image fresh porcine vocal cords after laser ablation. OCT and histology estimates of the ablation crater dimensions and the depth of thermal injury were obtained.

RESULTS: The vocal cord substructures up to 2.29 mm in depth at 10 μm resolution, and the thermal disruption after laser ablation were identified by OCT. OCT and histology estimates of the lesion dimensions showed no significant differences. Crater depth is directly proportional to laser power, whereas crater width and the zone of thermal injury appear to be unrelated to laser power.

CONCLUSIONS: OCT may be used to accurately characterize the native states and the laser-induced thermal injury of laryngeal mucosa, within the inherent limitation in its depth of penetration. OCT may be a useful diagnostic and monitoring tool in an otolaryngology practice.

Alterations of p53 and Bcl-2 protein expression in the laryngeal intraepithelial neoplasia

BACKGROUND

The squamous cell carcinoma of the larynx (SCC) is a common head and neck malignancy. I hypothesize that the development of laryngeal intraepithelial neoplasia (LIN) involves alterations of tumor suppressor genes (p53) and protooncogenes (Bcl-2).

METHODS

To test this hypothesis, 40 vocal cord biopsy specimens were examined for p53 and Bcl-2 protein expression using immunoperoxidase staining methods and mouse monoclonal antibodies.

RESULTS

The lesions appeared as localized , flat or papillary areas with white (leukoplakic) red (erythroplakic), or gray appearance. Histologically, the lesions entailed variable associations of mild (LIN I), moderate (LIN II), sever dysplasia (LIN III or in situ carcinoma) and superficially invasive SCC. As compared to the normal mucosa, the average weighted immunoreactivity scores for p53 and Bcl-2 proteins showed significant upregulation with the transitions from LIN I to LIN II to LIN III to superficially invasive SCC , respectively (0.0 +/- 0.0, 0.0 +/- 0.0, 1.8 +/- 0.8, 2.3 +/- 0.8, 5.8 +/- 3.2, p = 0.00 for p53 ) and (4.4 +/- 0.4, 4.0 +/- 0.8, 6.0 +/- 2.0, 9.6 +/- 1.6 and 10.7+/- 1.3, p = 0.00 for Bcl-2). There were insignificant positive correlation between p53 and both Bcl-2 (r = +0.8, p>0.13) protein expression.

CONCLUSIONS

Alterations of the p53 and Bcl-2 proteins occur during the development of SCC.

The effect of different angiolytic lasers on resolution of subepithelial mucosal hematoma in an animal model

OBJECTIVE

Vocal fold hematoma is traditionally managed with a period of voice rest, in the order of weeks, to allow natural resolution. This study is designed to examine the efficacy and safety of a number of hemoglobin-avid (vascular) lasers when used in the setting of acute vocal fold hematoma.

METHODS

Venous blood drawn from 4 white rabbits was used to create an array of subepithelial hematomas in the buccal cavities of each animal. Laser energy from I of 3 different lasers (532-nm pulsed potassium titanyl phosphate [KTP], 532-nm diode KTP, and 940-nm diode laser) was applied to each of the test hematomas at varying energy levels. Hematoma sites were photographed at days 0, 1, 5, 7, 9, and 12. Two animals were sacrificed on day 7 and the remainder on day 12. Histological evaluation of collateral tissue damage and residual hematoma was performed on biopsy specimens.

RESULTS

Macroscopic and microscopic ulceration at laser-treated sites was mostly resolved by day 7. Inflammatory cell infiltrate was present in laser-treated and hematoma-only sites. Laser-treated samples showed alterations in vascularity.

CONCLUSION

Hemoglobin-avid lasers may be beneficial in accelerating subepithelial hematoma resolution with a favorable tissue damage profile.

Anti-laminin-332 mucous membrane pemphigoid in a 9-year old girl

Mucous membrane pemphigoid (MMP), an autoimmune subepithelial blistering disease that predominantly affects the mucous membranes, is usually diagnosed in elderly adults. Early diagnosis of MMP is crucial because it tends to run a chronic and progressive course with the potential for devastating scarring of the mucous membranes that may lead to blindness and airway compromise. A subtype of MMP, anti-laminin-332 MMP, is a rare blistering disorder in which autoantibodies are directed against laminin-332 (formerly epiligrin), a structural protein of the epidermal basement membrane. Herein we report what we believe to be the youngest patient diagnosed with anti-laminin-332 MMP, a 9-year-old girl with disease affecting only the oral, pharyngeal, and laryngeal mucosa, with no skin involvement.

The role of contact endoscopy in screening for premalignant laryngeal lesions: a study of 141 patients

At their earliest stage, pathologic lesions of the laryngeal epithelium are macroscopically invisible. Ideally, these lesions should be detected before their clinical manifestations appear so that prompt management can be initiated. However, most diagnostic modalities are unable to detect early premalignant lesions. We conducted a retrospective study of the use of contact endoscopy in analyzing the vocal fold mucosal epithelium in adults who had been operated on at our hospital under general anesthesia for various nonlaryngeal diseases. After we identified 71 such patients who were smokers, we chose an almost equal number of nonsmokers (n = 70) for comparison purposes. In all, our study population was made up of 141 patients--51 men and 90 women, aged 21 to 78 years (mean: 52). All patients had normal findings on preoperative laryngeal endoscopy. Our goal was to determine if the routine use of this diagnostic modality is justified in selected cases. Contact endoscopy identified dysplastic vocal fold lesions in 4 patients and chronic laryngitis in 3; all 7 of these patients were smokers. Since early laryngeal lesions are not macroscopically evident, early detection of these changes by other means is associated with a better prognosis and easier management. Our study demonstrates that the use of contact endoscopy during general anesthesia as a standard diagnostic method in long-time cigarette smokers is fully justified.

[Aberrant expression of CyclinE and p27 in laryngeal squamous cell carcinoma and the clinical significance]

OBJECTIVE

To explore new hallmarks affecting the prognosis of patients with laryngeal squamous cell carcinoma (LSCC) via investigating the expression of CyclinE and p27 in LSCC tissues.

METHOD

The expression of CyclinE and p27 was detected via Elivision immunohistochemical staining in 160 LSCC tissues and 20 normal laryngeal tissues (NLT). The relationship between CyclinE/ p27 and LSCC/ NLT was analyzed via Log-rank analysis. The relationship of CyclinE and p27 protein was statistically analyzed by spearman correlation analysis. The relationship between CyclinE/p27 and clinical-pathology-factors of patients with LSCC, such as age, gender, tumor site, diameter, differentiation, lymph node metastasis and PTNM stage were analyzed by Chi-square test. The relationship between clinical-pathology-factors, CyclinE, p27 and overall survival time of patients with LSCC was analyzed via Cox multiplicity and Kaplan-Meier survival analysis. A significant difference was recognized by P<0.05.

RESULT

In LSCC the positive rates of CyclinE and p27 protein was 62.50% and 41.25% respectively (P<0.05). In NLT the positive rates of CyclinE and p27 protein was 35% and 70% respectively (P<0.05). The expression of CyclinE or p27 protein was closely correlated with lymph node metastasis, PTNM stage of patients with LSCC (P<0.05). The expression of CyclinE and p27 had no significant correlations with patients' gender, age and tumor site, diameter differentiation (P>0.05 for all). A negative correlation was found between the expression of CyclinE and p27 protein, r= -0.767(P<0.05). Kaplan-Meier survival analysis showed that the overall survival rate of patients with LSCC was 36.9% (P<0.05). The 5-year survival rate in positive group of CyclinE was 8%, in negative group was 80% (P<0.05). On the contrary, the 5-year survival rate of patients with LSCC in positive group of p27 protein was 77.27%, the rate was 5.32% in negative group (P<0.05). Cox multivariate regression analysis revealed that lymph node metastasis, PTNM stage, CyclinE and p27 were independent risk factors of prognosis for patients with LSCC.

CONCLUSION

It is the molecular basis underlying the development and invasion/ metastasis of LSCC that activation of CyclinE gene accompanying inactivation of p27 gene. It is very important of co-detecting CyclinE and p27 protein to predict the prognosis of patients with LSCC.

Detection of early laryngeal cancer and its precursor lesions by a real-time autofluorescence imaging system

The prognosis of laryngeal carcinoma patients can be improved by early diagnosis. The autofluorescence endoscopy has been developed to gain more information about the biologic character of the precancerous or cancerous lesions. The aim of the present study was to evaluate the diagnostic potential and limitations of this imaging technique applied during indirect laryngoscopy and comparing with white light and microlaryngoscopy with biopsy. In a prospective study, 56 patients with suspected precancerous or cancerous lesions were investigated preoperatively by white light and fluorescence endoscopy during indirect laryngoscopy. The procedure was followed by microlaryngoscopy and biopsy. Results were compared to histopathological findings. Normal laryngeal mucosa displayed a typical green fluorescence, moderate to high epithelial dysplasia, in situ carcinoma and cancer showed a diminished green fluorescence. In 47 of 56 (84%) cases, we found concordant results. The experience from this study shows that autofluorescence by indirect laryngoscopy may be a useful complementary method for detecting laryngeal malignancies. Its advantages are non-invasiveness, high sensitivity and repeatability.

[Hoarsness after a trip to the United States of America]

A 52 year old Swiss presented with a sore throat and progressive hoarseness. The histology showed a granulomatous inflammation of the epiglottis. Microbiology revealed dimorphic fungi in the sputum which were identified as Histoplasma sp. The histoplasma antigen was positive in urine and serum. Antimycotic therapy with itraconazol p.o. was started and switched to Amphotericin B i. v. due to clinical deterioration. Adrenal insufficiency should be considered in any patient with disseminated histoplasmosis since both the infection as well as the antimycotic treatment may cause Morbus Addison. An alternative therapy for the disseminated histoplasmosis is voriconazol. The investigation of the travel history is an important point.

A new rat model for investigation of subglottic stenosis

CONCLUSION

This study attempted to develop a new rat model of subglottic stenosis (SGS), resulting from subglottic mucosal injury administered by electrocauterization. Despite failure of the posterior SGS model, the anterior SGS model was considered feasible.

OBJECTIVE

To investigate the feasibility of using rats as an animal model for SGS.

METHODS

Thirty-seven female Sprague-Dawley rats were assigned to the control group or to the anterior or posterior subglottic injury group. Electrical cauterization was performed on the anterior or posterior 180° of the subglottic mucosa. Animals were euthanized at 4 weeks after injury. Histologic features of the subglottis were evaluated as regards changes in the subglottic lumen, lamina propria, cartilage, and epithelium after hematoxylin and eosin and Masson trichrome staining.

RESULTS

Survival in the anterior injury group was 80% (13/15) until 4 weeks, and results of histologic evaluation showed an increase in thickness of lamina propria with fibrosis and cartilage damage, resulting in luminal narrowing. A high rate of mortality was observed in the posterior injury group.

Genetic and protein markers related to laryngeal epithelial precursor lesions and their neoplastic progression

CONCLUSION

Various biomarkers might ultimately prove to have prognostic value and could be clinically relevant. It is mandatory confirm the prognostic power of these markers in large, well-designed, and prospective studies.

OBJECTIVE

The aim of this study was to investigate the possible role of specific genes and proteins in laryngeal tumorigenesis.

METHODS

Genetic analysis by multiple ligation-dependent probe amplification and analysis of protein expression by immunohistochemistry were carried out in a series of 50 tissue samples.

RESULTS

In the smoker normal mucosa group TP53 loss was predominant, whereas in the epithelial precursor lesions (EPLs) CDKN2A loss and BCL2L1 gain were most frequent. EPL with progression presented CTNNB1 loss. Positivity at cytoplasm for β-catenin, cyclin D1 and p53 was detected in all EPL cases with progression to invasive carcinoma. Multivariate analysis showed that expression of β-catenin and loss of CTTNB1 were associated with laryngeal cancer risk.

[Clinical classification and management of squamous intraepithelial lesions of the vocal cord]

OBJECTIVE

To discuss the clinical classification of the squamous intraepithelial lesions (SILs) of vocal cord and their outcomes after different therapeutic procedures.

METHODS

Three hundred and forty-three patients with the SILs of vocal cord were enrolled. Based on the history of the diseases, macroscopic appearance by video rhino aryngoscopic, stroboscopic and microlaryngoscopic examination, and pathological findings, the correlation of clinical features, treatment modalities and treatment effect of the vocal cord SILs were discussed.

RESULTS

According to the morphological characteristics, 343 patients were divided into four types. TypeI, leukoplakia combined with inflammation (n = 19); type II, leukoplakia combined with polyps by friction (n = 72); type III, leukoplakia combined with sulcus vocalis (n = 64); type IV, keratosis (n = 188). Patients with type I lesions were treated by medications. The vocal cord configuration and the voice of the patients in type I returned to normal after treatment. Patients with type II, III, IV lesions were treated by CO(2) laser. Type II were treated by subepithelial cordectomy, type III by mucosa slicing with dredging, type IV by sub ligament cordectomy or trans muscular cordectomy. The cure rate of patients with type II, III, IV lesions was 90.7% (294/324) after single surgery, the recurrent rate was 9.3% (30/324). Twenty-one patients (11.2%), all in type IV, developed carcinogenesis. Eight cases were diagnosed in the first surgery and 13 cases in the second. Among the 13 cases diagnosed in the second surgery, 2 cases had partial laryngectomy for the third surgery.

CONCLUSIONS

Since the squamous intraepithelial lesions of vocal cord manifested differently, conservative treatment or CO(2) laser surgery should be used. In this way, a less invasive procedure, better recovery of the voice and less complication could be expected.

[Expression of programmed cell death 4 and its correlation with proliferation and apoptosis in laryngeal squamous cell carcinoma]

OBJECTIVE

To study the expression of PDCD4 and its relationship with cell proliferation and apoptosis in laryngeal squamous cell carcinomas and to evaluate its clinical significance.

METHOD

The immunohistochemical staining method was applied to investigate the expression of PDCD4 and Ki-67 in 60 laryngeal squamous cell carcinomas tissues and 21 their surrounding laryngeal normal mucosa tissues. TUNEL method was applied to detect the apoptosis. The proliferation index (PI) and apoptosis index (AI) were defined.

RESULT

The positive rate of PDCD4 protein was significantly lower in laryngeal squamous cell carcinomas than that in the laryngeal normal mucosa tissues (P < 0.01). The expression of PDCD4 had relation with the differentiation grading and lymph node metastasis (P < 0.05), but not related to tumor sites and TNM stage. The PI of laryngeal squamous cell carcinomas tissues was higher than that of the normal laryngeal mucosa tissues (P < 0.01). No relation was found among PI and tumor sites, differentiation grading and lymph node metastasis. PI had correlation with TNM stage (P < 0.05). The AI of the cancer was higher than that of normal laryngeal mucosa tissues (P < 0.01). There was no relationship between AI and tumor sites, TNM stage and lymph node metastasis. AI correlated with differentiation grading (P < 0.01). The PI in PDCD4 positive group was significantly lower than in PDCD4 negative group (P < 0.05). The AI in PDCD4 positive group was significantly higher than in PDCD4 negative group (P < 0.05).

CONCLUSION

The expression of PDCD4 is low in laryngeal squamous cell carcinomas and it may play important roles in occurrence and development of laryngeal squamous cell carcinomas through the inducing apoptosis and inhibiting proliferation.

Biological and clinical significance of p75NTR expression in laryngeal squamous epithelia and laryngocarcinoma

CONCLUSION

The apparent features of p75 neurotrophin receptor (p75(NTR)) expression indicated that p75(NTR) would serve as a potential stem cell marker for normal human laryngeal squamous epithelia. In human laryngeal squamous cell carcinoma (LSCC) p75(NTR) is differentially expressed. The abnormal expression and distribution of p75(NTR) may indicate malignant transformation.

OBJECTIVE

To investigate the expression of p75(NTR) and its possible roles in normal laryngeal squamous epithelia and LSCC.

METHODS

We used immunohistochemistry methods to examine normal laryngeal epithelia, para-cancer mucosa with dysplasia, laryngeal papilloma, and LSCC specimens for the expression of p75(NTR), nerve growth factor (NGF), -tyrosine kinase receptor (TrkA), p63, and Ki67. Immunocytochemistry and flow cytometry were used to examine the expression of p75(NTR) in Hep-2 cells.

RESULTS

The expression of p75(NTR) was only located in basal cells of normal laryngeal epithelia, consistent with the staining features of epithelial stem cells as evidenced by parallel staining of p63, a putative keratinocyte stem cell marker. p75(NTR) is differentially expressed in LSCC, although no significant relationship was found with many clinicopathologic factors, this expression and distribution may correlate to malignant transformation and tumor proliferation. Co-expression of p75(NTR) and CD133 was confirmed, showing the association of p75(NTR)-positive cells with cancer stem cells in Hep-2 cells.

Histopathologic study of human vocal fold mucosa unphonated over a decade

CONCLUSION

Mechanotransduction caused by vocal fold vibration could possibly be an important factor in the maintenance of extracellular matrices and layered structure of the human adult vocal fold mucosa as a vibrating tissue after the layered structure has been completed.

OBJECTIVES

Vocal fold stellate cells (VFSCs) in the human maculae flavae of the vocal fold mucosa are inferred to be involved in the metabolism of extracellular matrices of the vocal fold mucosa. Maculae flavae are also considered to be an important structure in the growth and development of the human vocal fold mucosa. Tension caused by phonation (vocal fold vibration) is hypothesized to stimulate the VFSCs to accelerate production of extracellular matrices. A human adult vocal fold mucosa unphonated over a decade was investigated histopathologically.

METHODS

Vocal fold mucosa unphonated for 11 years and 2 months of a 64-year-old male with cerebral hemorrhage was investigated by light and electron microscopy.

RESULTS

The vocal fold mucosae (including maculae flavae) were atrophic. The vocal fold mucosa did not have a vocal ligament, Reinke's space or a layered structure. The lamina propria appeared as a uniform structure. Morphologically, the VFSCs synthesized fewer extracellular matrices, such as fibrous protein and glycosaminoglycan. Consequently, VFSCs appeared to decrease their level of activity.

Acute stress to excised vocal fold epithelium from reactive oxygen species

OBJECTIVES/HYPOTHESIS

Vocal fold epithelium is exposed to reactive oxygen species from the inhaled environment and from tissue inflammation. The objective of this study was to explore the functional and structural consequences of reactive oxygen species exposure on vocal fold epithelium.

STUDY DESIGN

In vitro, prospective study design.

METHODS

Hydrogen peroxide (H(2)O(2)), a common reactive oxygen species, was utilized in this study. Freshly excised, viable porcine vocal fold epithelia (N = 32) were exposed to H(2) O(2) or sham challenge for 2 hours. Electrophysiology, western blotting, and light microscopy were used to quantify the functional and structural effects of reactive oxygen species on vocal fold epithelia.

RESULTS

Exposure to reactive oxygen species did not significantly alter transepithelial resistance. There was a small, nonsignificant trend for decreased concentration of epithelial junctional complex protein with reactive oxygen species challenge. Minimal changes to the gross structural appearance of vocal fold epithelia were also noted.

CONCLUSIONS

The stratified squamous epithelia of the vocal folds effectively defend against an acute reactive oxygen species challenge. The current study lays the groundwork for future investigations on the effects of reactive oxygen species on vocal fold epithelia that are compromised from phonotrauma.

Histopathological markers for the diagnosis of anaphylactic death

The postmortem diagnosis of anaphylactic death may be frustrating when victims are not hospital patients, even more so when they are recovered dead. The frequent lack of specific morphological findings in such cases means that diagnosis by the forensic pathologist must rely solely on exclusion criteria or circumstantial evidence. However, a diagnostic approach based on case history, analysis of circumstances, available clinical and necropsy findings, as well as toxicology, histopathology and biohumoral data, often allows demonstration of the cause of death. Some useful reflections on microscopic morphological data have come from two recent cases, where thorough data collection provided a reasonably certain diagnosis of anaphylactic death and systemic inflammatory response syndrome-related cardiac arrest, respectively. In both cases tissue histopathology proved crucial, since histochemical (GIEMSA) and immunohistochemical analysis (CD117 and tryptase) documented a large number of mast cells in tissues, particularly the laryngeal wall, and a discrepancy between cells positive for GIEMSA and tryptase and those positive for CD117. Staining for CD117 was also detected in cells with dendrite morphology and in a subpopulation of small lymphocytes with incised nuclei. The morphological findings of these cases are discussed, especially those obtained with immunohistochemistry, and the need for the latter data to be interpreted by experienced medical staff in the framework of a thorough analysis of all the data collected is highlighted.

LOXL4 as a selective molecular marker in primary and metastatic head/neck carcinoma

BACKGROUND

Overexpression of the lysyl oxidase-like 4 (LOXL4) gene is associated with a variety of human malignancies. The purpose of this study was to compare the gene expression of LOXL4 to the expression of epidermal growth factor receptor (EGFR) in head and neck squamous cell carcinomas. The overexpression of EGFR has been well examined and already serves as a therapeutic target. The expression of both genes was compared in head and neck squamous cell carcinomas and their diagnostic and prognostic value was evaluated.

MATERIALS AND METHODS

Messenger RNA from 58 head and neck carcinomas and 11 healthy upper aerodigestive tract mucosa samples was extracted and subjected to electrophoresis. Northern hybridisation was carried out using digoxigenin-labelled gene-specific probes, and the level of gene expression was measured by densitometry.

RESULTS

High expression of LOXL4 gene was detected in 71% of all carcinomas and only in 9% of the healthy mucosa samples (p=0.0002). In comparison, a high level of expression was detected for the EGFR gene in 78% of the carcinomas and in 36% of normal mucosa (p=0.01).

CONCLUSION

Although both genes revealed a similar level of overexpression in the carcinoma samples, it was found that the a notably higher percentage of healthy mucosa tested positively for EGFR than LOXL4, indicating that LOXL4 may serve as a selective molecular marker in primary and metastatic head and neck carcinoma.

[Non-Hodgkin lymphoma of the larynx]

Primary non-Hodgkin lymphoma of the larynx is rare, accounting for less than 1% of all laryngeal neoplasms. Fewer than 100 cases have been reported in the literature. This case describes a 76-year-old woman with primary non-Hodgkin lymphoma of the larynx. To our knowledge, this is the first case of primary non-Hodgkin lymphoma of the larynx reported in the Danish literature.

[Leishmaniasis isolated to the larynx as cause of chronic laryngitis]

Mucosal leishmaniasis is uncommon outside Central and South America, where it is commonly caused by Leishmania (L.) braziliensis. We present a case of isolated laryngeal leishmaniasis detected in a 78-year-old male, who presented with chronic hoarseness. Histologic examination of biopsies taken from the larynx showed L. amastigotes. An L.-specific indirect fluorescent antibody test was positive. Polymerase chain reaction showed infection with L. donovani, L. infantum or L. tropica, species which do not normally cause isolated mucosal infection. This is the first reported case from Scandinavia.

[Primary, study of miRNA expression patterns in laryngeal carcinoma by microarray]

OBJECTIVE

To detect the expression of microRNAs (miRNAs) in laryngeal carcinoma and adjacent normal tissue using microarray, and to discuss the relationship between miRNAs and laryngeal carcinoma.

METHOD

miRNA were extracted from 8 cases of laryngeal cancer tissue and its adjacent normal tissue. miRNA identification were performed by microarray of miRNA hybridization and cluster analysis was used with Significance Analysis of Microarrays (SAM, version 2.1) and Cluster 3.0 software. miRNA were confirmed by real time quantification RT-PCR with RNA-tailing and primer extension.

RESULT

Totally 47 different miRNAs were found expressed in laryngeal cancer, with 23 of miRNA expression were up-regulated and 24 of miRNA expression were down-regulated. The expression of miR-1, miR-486-5p, miR-206, miR-487a,miR-375, miR-422a, miR-144, miR-384, miR-378, miR-133a were down-regulated by 5 multiple and while expression of miR-93, miR-31, miR-20b were up-regulated by 3 multiple. There are 5 miRNA clusters with coexpression in laryngeal cancer tissue and located on chromosome 8, 13, 14, 18 and X. Moreover, RT-PCR analysis demonstrated that there was no significantly difference of miRNA expression between microarray and RT-PCR.

CONCLUSION

The different expression of miRNA may play an important role in the pathogenesis and development of laryngeal cancer.

[Tissue reactions of the laryngeal mucous membrane and its regulatory structures in experimental chronic laryngitis]

Experimental chronic laryngitis (ECL) was induced in 34 adult male rabbits by placement of fosta nylon thread into their trachea. Changes in the laryngeal mucous membrane in ECL were studied at days 30-90 using histological, histochemical and morphometric methods. ECL resulted in the thickening of both the epithelium and lamina propria of the laryngeal mucous membrane. In the ECL dynamics, the thickness of stratified squamous epithelium was increased insignificantly, however, it demonstrated the stimulation of the focal hyperplastic processes. Lamina propria, underlying this epithelium, was found to become thicker throughout the whole experiment (days 30-90). At the same time, progressive growth of the thickness of both pseudostratified ciliated epithelium and the lamina propria beneath was observed. This was accompanied by the hyperplasia of laryngeal endocrine cells and the increase of their secretory activity.

[Expression of EMS1 protein and its clinical significance in laryngeal carcinoma]

OBJECTIVE

To investigate the expression of EMS1 in laryngeal carcinoma and its clinical significance.

METHOD

The expression of EMS1 protein was measured in 40 samples of, 40 samples of para carcinoma tissues (which were near to cutting margin of laryngeal carcinoma tissue over 0.5 cm), and 20 samples of normal laryngeal mucosa as controls by Flow Cytometer (Epics-XL II).

RESULT

The quantity and percentage of EMS1 protein expression in laryngeal carcinoma tissues was significantly higher than those in para carcinoma and in normal laryngeal mucosa tissues respectively (P<0.05). There was no significant expression difference between the para carcinoma tissues and normal laryngeal mucosa tissues. There were positive correlation between the expressions of EMS1 protein and metastasis, pathological grade and clinical stage in laryngeal carcinoma. But there were not relationship with patients' clinical classification, tumor size, smoking history, age and sex.

CONCLUSION

The high expression of EMS1 may contribute to the carcinogenesis and development of laryngeal carcinoma. The expression of EMS1 protein is an important index of judging differentiation, infiltration, metastasis and staging of laryngeal carcinoma.

[Dynamic observation of applying repairing laryngeal mucosal defect with heterogeneous acellular dermal matrix]

OBJECTIVE

To study the clinical effect of heterogeneity (cattle) acellular dunal matrix in repairing mucosa defect in laryngeal surgery.

METHODS

Eighteen cancer patients with mucosa defect in central vocal area accepted treatment with heterogeneity acellular dunal matrix after surgery. There were two methods to repair mucosa defect. One was simple use of acellular dunal matrix, the second was combined use of acellular dunal matrix and muscle lamella or muscle and tendon film lamella. 18 cases had cancer in central vocal area: T2N0M0 (8), T3N1M0 (5), T3N2M0 (4), T4N2M0 (1). All were squamous cell carcinoma. Ten cancer patients accepted radiation after surgery. The radiotherapy volume was 60-80 Gy. After the operation, the patients were checked by fibrolaryngoscope four or five times after half a year, observing the dynamic development.

RESULTS

All 18 patients were healed, rechecked by endoscope after 0.5-6 months, heterogeneity acellular dunal matrix mingled with mucosa within 30-60 d, no allergy and irritation were found. The laryngeal function, including breathing, pronouncing and swallowing, was recovered. The survival rate (1 year) was 100%, and 10 patients survived after 2 years. After radiotherapy, the process of recovery was not affected.

CONCLUSIONS

Heterogeneity acellular dunal matrix can be easily obtained and it is a new method to repair mucosa defect. The operative procedure is easy to perform and worthwhile to use clinically.

[The expression of oncogene AKT2 in laryngeal squamous cell carcinoma and its clinical significance]

OBJECTIVE

To investigate the expression and clinical significance of oncogene AKT2 in laryngeal squamous cell carcinoma (LSCC).

METHOD

The expression of AKT2 protein was measured with immunohistochemistry (Elivision two steps) in 60 cases of LSCC tissue, 28 cases of peri-cancer tissue and 16 cases of normal laryngeal epithelium, the relationship between AKT2 expression and clinical pathologic factors in LSCC was also analyzed.

RESULT

The positive rates of AKT2 protein expression in LSCC and peri-cancer tissue were 56.7% (34/60), 14.3% (4/28) respectively. There was no expression of AKT2 in normal laryngeal epithelium. The positive rate of AKT2 protein expression in LSCC was significantly higher than that in peri-cancer tissue and normal laryngeal epithelium (P < 0.05, respectively). The positive rate of AKT2 was correlated with tumor site, lymph node metastasis and clinical stage of LSCC (P < 0.05, respectively), but wasn't correlated with patient's age, sex, and T stage (P > 0.05, respectively).

CONCLUSION

AKT2 might play an important role in the tumorigenesis and development of LSCC, and it was suggested that AKT2 could be a useful marker for predicting tumorigenesis, invasion and metastasis potential of LSCC.

Reflux-associated laryngitis and laryngopharyngeal reflux: a gastroenterologist's point of view

Laryngopharyngeal reflux of liquid and gaseous gastric contents should be considered in every patient with unexplained hoarseness. Pathophysiology and treatment of reflux-associated laryngitis are different from those of reflux esophagitis and therefore remain an unsolved puzzle. The laryngeal mucosa is considerably more sensitive to acid and pepsin than the mucosa of the esophagogastric junction. Therefore definitions of acid and nonacid reflux used for gastroesophageal reflux disease may not be helpful for explaining pathophysiologic mechanisms in the larynx or pharynx. A reflux symptom index and reflux finding score may be useful in helping to select the minority of patients who may benefit from acid-suppressive therapy; however, further research is needed. Further research is also needed to identify those patients who may require higher doses or prolonged duration of proton pump inhibitors or alternative treatments like prokinetics or alginate, or those patients who may benefit from surgical treatment of gastroesophageal reflux. Since symptoms of laryngopharyngeal reflux may predict esophageal adenocarcinoma, every patient with laryngopharyngeal reflux should have an upper gastrointestinal endoscopy, even if no classical symptoms of gastroesophageal reflux disease are present.

Retinoid X receptor overexpression desensitizes laryngeal epithelium to carcinogenic effects associated with epidermal growth factor receptor upregulation

OBJECTIVE

Squamous cell carcinomas (SCCs) of the larynx are sequelae of hyperplastic and dysplastic lesions. Epidermal growth factor receptor (EGFR) is found frequently overexpressed in SCCs of the head and neck, although its regulatory role is not fully elucidated. Conversely, retinoid X receptor alpha (RXRalpha) mediates the reversing effects of retinoids on head and neck carcinogenesis. We examined the expression of EGFR in relation to the progress of laryngeal tumorigenesis and how this association is modulated by concurrent RXR presence.

DESIGN

A retrospective study.

SETTING

A basic research anatomy laboratory, operating within a tertiary care institution.

MATERIALS

Tissue samples from 129 patients with premalignant or malignant laryngeal lesions.

METHOD

Paraffin-section immunohistochemistry.

MAIN OUTCOME MEASURES

EGFR immunoreactivity in relation to histopathology progression, in both the presence and absence of RXR immunoexpression.

RESULTS

EGFR was upregulated along the epithelial deterioration toward neoplasia (p < .001) but was unaffected by tumour grade. In RXRalpha-positive cases, a markedly stronger induction of EGFR occurred with malignant transformation compared with the epithelia immunonegative for the nuclear receptor.

CONCLUSION

This study suggests that RXRalpha confers to squamous cells a shielding effect against excessive mitogenic stimulation, which might be EGFR dependent. RXR-positive patients manifesting resistance to anti-EGFR agents could benefit from rexinoid administration.

Activity/Stability of Human Pepsin: Implications for Reflux Attributed Laryngeal Disease

OBJECTIVES/HYPOTHESIS

Exposure of laryngeal epithelia to pepsin during extra-esophageal reflux causes depletion of laryngeal protective proteins, carbonic anhydrase isoenzyme III (CAIII), and squamous epithelial stress protein Sep70. The first objective of this study was to determine whether pepsin has to be enzymatically active to deplete these proteins. The second objective was to investigate the effect of pH on the activity and stability of human pepsin 3b under conditions that might be found in the human esophagus and larynx.

STUDY DESIGN

Prospective translational research study.

METHODS

An established porcine in vitro model was used to examine the effect of active/inactive pepsin on laryngeal CAIII and Sep70 protein levels. The activity and stability of pepsin was determined by kinetic assay, measuring the rate of hydrolysis of a synthetic pepsin-specific substrate after incubation at various pH values for increasing duration.

RESULTS

Active pepsin is required to deplete laryngeal CAIII and Sep70. Pepsin has maximum activity at pH 2.0 and is inactive at pH 6.5 or higher. Although pepsin is inactive at pH 6.5 and above, it remains stable until pH 8.0 and can be reactivated when the pH is reduced. Pepsin is stable for at least 24 hours at pH 7.0, 37 degrees C and retains 79% +/- 11% of its original activity after re-acidification at pH 3.0.

CONCLUSIONS

Detectable levels of pepsin remain in laryngeal epithelia after a reflux event. Pepsin bound there would be enzymatically inactive because the mean pH of the laryngopharynx is pH 6.8. Significantly, pepsin could remain in a form that would be reactivated by a subsequent decrease in pH, such as would occur during an acidic reflux event or possibly after uptake into intracellular compartments of lower pH.

[Relationship between vocal fold leukoplakia and gastropharyngeal reflux:analysis of 15 cases]

OBJECTIVE

To explore the possible relationship between vocal fold leukoplakia and gastropharyngeal reflux.

METHODS

Fifteen patients with vocal fold leukoplakia confirmed by pathology, all males, aged (53 +/- 14) (20-88), underwent esophageal and laryngopharyngeal 24-hour pH monitoring before operation. The rate and characteristics of reflux were recorded. Semi-open-ended questionnaire was used to assess the symptoms.

RESULTS

Nine of the 15 patients (60%) showed pathologic intra-esophageal reflux. The time of total acid reflux of the positive re intra-esophageal reflux group was 104.6 min +/- 42.1 min, significantly longer than that of the negative group [(10.9 min +/- 11.5 min), P = 0.001]. The frequencies of intra-esophageal acid reflux of the positive group was (30.1 +/- 16.2) times, significantly higher than that of the negative group [(4.8 +/- 3.4) times, P = 0.006]. The intra-esophageal acid reflux percentage of the positive group was 7.9% +/- 2.9%, significantly higher than that of the negative group [(1.0% +/- 0.6%), P = 0.01]. and the rate in esophageal pH <4 of total fraction time between reflux positive and negative patients (P < 0.01). The scores of heartburn and acid regurgitation of the positive group were significantly higher than those of the negative group (both P < 0.05). Two of 15 patients (13.3%) had pathologic laryngopharyngeal reflux. One patient also had obstructive sleep apnea hypopnea syndrome.

CONCLUSION

The patients with vocal fold leukoplakia had more pathologic intra-esophageal reflux compared to the normal individuals. Reflux may be a risk factor of mucosa leukoplakia. Leukoplakia;

[Expression and clinical significance of breast cancer metastasis suppressor 1 mRNA in supraglottic laryngeal carcinoma]

OBJECTIVE

To investigate the expression of breast cancer metastasis suppressor 1 (BRMS1) mRNA in supraglottic cancer and to evaluate its clinical significance.

METHOD

The expression of BRMS1 mRNA was examined by using RT-PCR method which take beta-actin mRNA as reference template in 66 cases of supraglottic cancer tissues and their adjacent normal mucosa tissues (ANT).

RESULT

The expression of BRMS1 mRNA in the tissues of supraglottic cancer is lower significantly than that in the tissues of ANT ( P<0.05). There is correlation between BRMS1 mRNA expression and the clinical stage, differentiation and cervical lymph node metastasis in the laryngeal supraglottic cancers (P<0.05). There is no correlation between BRMS1 mRNA expression and sex and age.

CONCLUSION

Expression of BRMS1 mRNA in supraglottic cancer is lower than that in adjacent normal mucosa. The decrease of BRMS1 mRNA expression may be related to clinical stage and low differentiation and lymph node metastasis of supraglottic laryngeal cancer.

[Expression and prognostic significance of cyclooxygenase-2 in supraglottic laryngeal squamous cell carcinomas]

OBJECTIVE

To study the expression and prognostic significance of cyclooxygenase-2 (Cox-2) in supraglottic laryngeal squamous cell carcinomas (SGLSCC) and identify the relationship between Cox-2 and angiogenesis and the roles of Cox-2 in SGLSCC as a biological marker.

METHOD

Eighty-eight primary SGLSCC patients received surgical treatment were studied by immunohistochemical staining, and reverse transcription-polymerase chain reaction (RT-PCR) technique.

RESULT

The percentage of Cox-2-positive cells was 94.3% (83/88) in SGLSCC whereas there was no immunostaining in the all cells of normal mucosa of paracarcinoma. Cox-2 expression was higher in well-differentiated tumors compared with poorly-differentiated SGLSCC. The relative concentration of Cox-2 mRNA was 141.871 +/- 20.5435 in SGLSCC and 17.031 +/- 2.2597 in normal paracarcinoma mucosa (P < 0.01). It was significantly higher in SGLSCC than in normal paracarcinoma mucosa. In SGLSCC, only pathological grading and the percentage of Cox-2-positive cells had significant correlation (P < 0.01). And not only the percentage of Cox-2-positive cells but also Cox-2 intensity had significant correlation with microvessel density (MVD) (P < 0.01). Kaplan-Meier survival analysis showed there had significant relationship between Cox-2 intensity and cumulative survival rate of SGLSCC patients (P < 0.05). But the percentage of Cox-2-positive cells was different (P > 0.05). Cox's regression analysis indicated that Cox-2 intensity were significantly independent prognostic factors (P < 0.01).

CONCLUSION

Cox-2 expression maybe relate to the carcinogenesis and progress in tumors especially in well-differentiated ones; The changes of Cox-2 expression are synchronous with MVD. Cox-2 intensity is a significantly independent prognostic factor. So Cox-2 may be an effective target of prevention, therapy and prognostic evaluation for laryngeal carcinoma and other head and neck squamous cell carcinomas (HNSCC).

Expression of PTEN protein in patients with laryngeal squamous cell carcinoma

OBJECTIVE

PTEN (phosphatase and tensin homologue deleted on chromosome 10), also referred to as MMAC1 (mutated in multiple advanced cancers) gene was recently identified as a putative tumor suppressor in a variety of malignant tumors. PTEN expression has been investigated in some squamous cell carcinomas (SCC) of head and neck. However, there is only little knowledge about laryngeal malignancies. Therefore, we examined PTEN product protein immunohistochemically in 30 consecutive laryngeal specimens from patients with laryngeal SCC and compared the results according to the clinicopathologic characteristics of the patients.

METHOD

Surgical resection specimens of patients with laryngeal SCC were stained for PTEN protein using a primary rabbit polyclonal anti-PTEN antibody. Standard avidin-biotin immunohistochemical analysis was used to process the sections. The extent and intensity of PTEN staining in the specimens were compared according to the age and sex of the patients and localization, differentiation, size and stage of the tumor.

RESULTS

Out of 30 tumoral specimens (23 glottic and 7 supraglottic) 22 showed decreased PTEN staining intensity compared to the adjacent normal tissue. The extent of cytoplasmic PTEN staining was significantly less in supraglottic tumors (p < 0.05). When characteristics of the patients were analyzed according to the extent of cytoplasmic PTEN staining no difference was observed according to age, sex, measure, differentiation, T or N status.

CONCLUSION

A significant decrease in the extent of PTEN staining was observed in supraglottic SCC. It could be worthwhile to test if PTEN expression is diminished in patients with more aggressive laryngeal tumors, with special attention to tumor localization in larger series.

A new approach to geometrical measurements in an animal model of vocal fold scar

A standard method for quantifying the geometric properties of vocal folds has not been widely adopted. An ideal method of geometrical measurement should effectively quantify the dimensions of the medial vibratory portion of the vocal fold, should be easily performed, should yield consistent results, and should be readily available at little to no cost. We have developed a new approach for geometrical measurements to meet these goals. The objective of this study is to describe this new approach and to assess its effectiveness in a canine model of vocal fold scar. One hundred thirty-five mid-membranous coronal sections of vocal folds from 10 canines (five with unilateral surgical scarring) were examined by light microscopy; digital images were captured. ImageJ was used to measure a variety of described parameters. Comparison between scarred vocal folds and control vocal folds was made. At least 20% of the slides for each vocal fold were randomly selected (n=42) for repeat measurements of interrater and intrarater reliability. A statistically significant difference between scarred and control vocal folds was obtained for horizontal distance (P<0.001), vertical distance (P=0.005), area (P<0.001), mean optical density (OD) (P<0.001), and OD at defined points along the length of the vocal fold (P< or =0.009). Reliability calculations for intrarater and interrater measurements ranged from r=0.845 to r=0.994 and from r=0.734 to r=0.976, respectively. The proposed approach for geometrical measurements meets the intended objectives in a canine model of vocal fold scar. Future work is needed to apply this approach to other model systems.

[The expression and significance of HIF-1alpha and COX-2 in laryngeal squamous cell carcinoma]

OBJECTIVE

To investigate the protein and mRNA expression of HIF-1alpha and COX-2 in laryngeal squamous carcinoma, and their correlation with clinicopathologic parameters.

METHOD

The protein and mRNA expression of HIF-1alpha and COX-2 in fresh laryngeal squamous carcinoma tissues and adjacent normal tissues from 76 patients were examined by immunohistochemistry and reverse transcription polymerase chain reaction.

RESULT

1) The protein positive expression rate of HIF-1alpha and COX-2 in tumor samples were significantly higher than that in normal tissues (P < 0.05); The protein positive expression rate of HIF-1alpha were higher in moderately and poorly differentiated tumors than in well differentiated tumors (P < 0.05); While the protein positive expression rate of COX-2 were not associated with T stage (P > 0.05); 2) The mRNA positive expression rate of HIF-1alpha and COX-2 were 67.11% and 75.00% respectively, their expression were significantly higher in tumors than that in normal tissues (P < 0.05). The mRNA expression of COX-2 were not detected in normal tissues. The mRNA positive expression rate of HIF-1alpha were associated with T stage, but were not associated with differentiated clinicopathologic stage. 3) The protein positive expression rate of HIF-1alpha were associated with that of COX-2.

CONCLUSION

HIF-1alpha and COX-2 could up regulate each other to promote the development and metastasis of laryngeal squamous carcinoma.

[The expressions and significance of CK2 in normal laryngeal mucosa, laryngeal precancerosis and laryngeal squamous cell carcinoma]

OBJECTIVE

To investigate the expression of protein kinase CK2 and its relationship with the development, progress, invasion and metastasis of squamous cell carcinoma of larynx (LSCC).

METHOD

Immunohistochemical SP staining method was used to assess the expression of CK2 in 18 cases of normal laryngeal mucosa, 14 cases of polyp of vocal cord, 11 cases of larynx papilloma and 50 cases of LSCC patients. And RT-PCR was used to detect the expression of CK2alpha mRNA and CK2beta mRNA in 50 cases of LSCG patients. The relationship between CK2alpha and CK2p was evaluated.

RESULT

The positive expression rate of CK2alpha and CK2beta in normal laryngeal mucosa, polyp of vocal cord and tissues close to carcinoma by 1.0 cm, nonmetastatic lymph nodes were lower than that in tissues close to carcinoma by 0.5 cm and laryngeal papilloma. The positive expression rate of CK2alpha and CK2beta in laryngeal carcinoma and metastatic lymph nodes were the highest among the groups. The expression rate of CK2alpha and CK2beta in tissues of laryngeal carcinoma and metastatic lymph nodes of neck was significantly higher than that of laryngeal papilloma and tissues close to carcinoma by 0.5 cm (P < 0.05). In the group of LSCC, the expression of CK2alpha in G2 and in G3 was significantly higher than that in G1 (P < 0.05). While the age of the patients, TNM stage and lymphatic metastasis didn't change in the expression of CK2alpha obviously. The expression of CK2beta correlates to the differentiation grading and lymphatic metastasis in LSCC patients, but not to the age and TNM stage. The result from RT-PCR was highly consistent with that from immunohistochemical SP staining. There was a positive correlation between the expression of CK2alpha in LSCC patients and that of CK2beta.

CONCLUSION

The over expression of protein kinase CK2 may be an accelerator to the formation and development of LSCC. Protein kinase CK2 may be one of the predictors for the malignant grade of LSCC. To inhibit the over expression might be new therapeutic methods for LSCC.