Intensity-modulated radiotherapy with planned Gamma Knife radiosurgery boost for head and neck cancer with extensive disease in proximity to critical structures

BACKGROUND

To describe intensity-modulated radiotherapy (IMRT) with Gamma Knife Radiosurgery (GKRS) boost for locally advanced head and neck cancer (HNC) with disease near dose-limiting structures.

METHODS

Patients with HNC treated with IMRT/GKRS as part of a combined modality approach between 2011 and 2021 were reviewed. Local control, overall survival and disease-specific survival were estimated using the Kaplan Meier method.

RESULTS

Twenty patients were included. Nineteen patients had T3-4 tumors. Median follow-up was 26.3 months. GKRS site control was 95%. Two patients progressed at the treated primary site, one patient failed at the edge of the GKRS treatment volume, with no perineural or intracranial failure. 2-year OS was 94.7% (95% CI: 85.2%-100%). Concurrent chemotherapy was given in nine patients (45%). One patient (5%) received induction/concurrent chemotherapy. Brain radionecrosis occurred in three patients, one of which was biopsy-proven.

CONCLUSIONS

IMRT plus GKRS boost results in excellent disease control near critical structures with minimal toxicity.

A comparison of digestate management options at a large anaerobic digestion plant

Increased biogas production from increasing numbers of anaerobic digestion (AD) facilities has increased the mass of digestate applied to agricultural land close to AD plants and has led to an oversupply in some regions. This necessitates long distance digestate transportation accompanied by economic, environmental, and social drawbacks. This work assesses the performance of three different digestate management options (MOs); land application of whole digestate (MO1), digestate separation (MO2), and digestate separation and evaporation (MO3), combined with centralised or decentralised digestate storage. All MOs required the same landbank area, whilst MO2 and MO3 reduced digestate management costs by 9% and 37% (if recovered heat is used) respectively. GHG emissions from MO2 were 41% lower than MO1 if renewable electricity was used. MO3 reduced GHG emissions by 63% compared to MO1, if renewable electricity and recovered heat were used. MO2 required the same centralised digestate storage volume as MO1 while MO3 required 44% of the centralised storage volume. Centralised digestate storage required a maximum of 79 days for digestate transportation (33 trucks/day, 20 m³ capacity) to land for MO1 and MO2, and 35 days for MO3. Decentralised digestate storage required 63 storage tanks and 15 trucks/day for MO1, 69 tanks and 15 trucks/day for MO2, and 68 tanks and 7 trucks/day for MO3. Tank size ranged from 500 m³ to 20,000 m³. MO3 combined with decentralised storage could reduce the cost and GHG emissions (if recovered energy is used), vehicle movements, and the number of storage tanks required for digestate management.

Comprehensive gene cluster analysis of head and neck squamous cell carcinoma TCGA RNA-seq data defines B cell immunity-related genes as a robust survival predictor

BACKGROUND

The authors aimed to define novel gene expression signatures that are associated with patients' survival with head and neck squamous cell carcinoma (HNSCC).

METHODS

TCGA RNA-seq data were used for gene expression clusters extraction from 499 tumor samples by the "EPIG" method. Tumor samples were then partitioned into lower and higher than median level groups for survival relevant analysis by Kaplan-Meier estimator.

RESULTS

We found that two gene clusters (_1, _2) are favorably, while two (_3, _4) are unfavorably, associated with patients' survival with HNSCC. Notably, most genes on the top lists of cluster_2 are associated with B cells. A gene expression signature with combined genes from cluster_2 and _4 was further determined to be associated with HNSCC survival rate.

CONCLUSION

Our work strongly supported a favorable role of B cells in patients' survival with HNSCC and identified a novel coexpressed gene signature as prognostic biomarker for patients' survival with HNSCC estimation.

Detection and localization of surgically resectable cancers with a multi-analyte blood test

Earlier detection is key to reducing cancer deaths. Here, we describe a blood test that can detect eight common cancer types through assessment of the levels of circulating proteins and mutations in cell-free DNA. We applied this test, called CancerSEEK, to 1005 patients with nonmetastatic, clinically detected cancers of the ovary, liver, stomach, pancreas, esophagus, colorectum, lung, or breast. CancerSEEK tests were positive in a median of 70% of the eight cancer types. The sensitivities ranged from 69 to 98% for the detection of five cancer types (ovary, liver, stomach, pancreas, and esophagus) for which there are no screening tests available for average-risk individuals. The specificity of CancerSEEK was greater than 99%: only 7 of 812 healthy controls scored positive. In addition, CancerSEEK localized the cancer to a small number of anatomic sites in a median of 83% of the patients.

MicroRNA Profiling and Target Genes Related to Metastasis of Salivary Adenoid Cystic Carcinoma

BACKGROUND/AIM

Perineural invasion and distant metastasis lead to a poor prognosis of adenoid cystic carcinoma and there is no effective therapy available. MicroRNAs (miRNAs) are small non-coding RNAs that regulate target gene expression, which can be biomarkers or therapeutic targets for certain cancer types. We aimed to identify miRNAs and their target genes possibly involved in metastasis of salivary gland adenoid cystic carcinoma (SACC).

MATERIALS AND METHODS

Using Nanostring nCounter analysis, we examined miRNA expression in two SACC cell lines: SACC-83 and SACC-LM, with low and high lung metastasis rates, respectively. We then verified the differentially expressed miRNAs with real-time polymerase chain reaction in the cell lines and in tumor samples from patients with SACC. miRNA target-gene expression was also analyzed.

RESULTS

SACC-83 showed higher gene expression of miR-130a, miR-342, and miR-205; SACC-LM showed higher gene expression of miR-99a and miR-155. In human tissue, miR-205 was highly expressed in the primary SACC, while miR-155 and miR-342 were highly expressed in recurrent SACC. Six predicted target genes of miRNA-155 and miR-99a linked to tumorigenesis were further analyzed and RNA expression of ubiquitin-like modifier activating enzyme 2 (UBA2) was higher in SACC than normal salivary gland tissue, and higher in primary compared to recurrent SACC (p<0.05). RNA expression of retinoic acid receptors (RARS) was higher in tissue from primary than recurrent SACC and normal salivary gland (p<0.05), but that in recurrent SACC was not significantly higher than normal salivary gland tissue. RNA expression of minichromosome maintenance 8 homologous recombination repair factor (MCM8) and 24-dehydrocholesterol reductase (DHCR24) was higher in primary SACC than normal salivary gland tissue (p<0.05).

CONCLUSION

miR-99a, miR-155, miR-130a, miR-342, and miR-205 may play a role in metastasis of SACC. MiR-155 may be involved in SACC metastasis through UBA2 pathways, and UBA2 may function as a biomarker/mediator of SACC metastasis.

Gene Variability Between Perineural-positive and Perineural-negative Squamous Cell Skin Cancers

AIM

To identify differentially expressed genes (DEGs) between perineural invasion-positive (PP) and -negative (PN) cutaneous squamous cell cancers (CSCC).

MATERIALS/METHODS

Forty CSCC samples with and without perineural invasion were processed for RNA isolation and hybridization to Affymetrix-U219 DNA microarrays. Raw gene expression data were normalized by Robust Multi-array Averaging (RMA) and log2 transformed. Gene expression-based classification models were created and accuracies evaluated using leave-one-out cross-validation.

RESULTS

At a stringent limma p-value (p<0.001), 24 genes were differentially expressed between PP and PN samples. The cross-validated performance of the eight classification models exhibited a mean accuracy of 85-95%. Diagonal linear discriminant was most accurate at 95%, followed by Bayesian compound covariate at 94%. The poorest accuracy (85%) was observed for 1-Nearest neighbor and Support vector machines.

CONCLUSION

Gene expression may distinguish between PP and PN CSCC. Understanding these gene patterns may potentiate more timely diagnosis of perineural invasion and guide comprehensive therapies.

Chemokine and Chemokine Receptor Profiles in Metastatic Salivary Adenoid Cystic Carcinoma

AIM

To characterize the chemokine pattern in metastatic salivary adenoid cystic carcinoma (SACC).

MATERIALS AND METHODS

Real-time polymerase chain reaction (RT-PCR) was used to compare chemokine and chemokine receptor gene expression in two SACC cell lines: SACC-83 and SACC-LM (lung metastasis). Chemokines and receptor genes were then screened and their expression pattern characterized in human tissue samples of non-recurrent SACC and recurrent SACC with perineural invasion.

RESULTS

Expression of chemokine receptors C5AR1, CCR1, CCR3, CCR6, CCR7, CCR9, CCR10, CXCR4, CXCR6, CXCR7, CCRL1 and CCRL2 were higher in SACC-83 compared to SACC-LM. CCRL1, CCBP2, CMKLR1, XCR1 and CXCR2 and 6 chemokine genes (CCL13, CCL27, CXCL14, CMTM1, CMTM2, CKLF) were more highly expressed in tissues of patients without tumor recurrence/perineural invasion compared to those with tumor recurrence. CCRL1 (receptor), CCL27, CMTM1, CMTM2, and CKLF (chemokine) genes were more highly expressed in SACC-83 and human tissues of patients without tumor recurrence/perineural invasion.

CONCLUSION

CCRL1, CCL27, CMTM1, CMTM2 and CKLF may play important roles in the development of tumor metastases in SACC.

Head and Neck Cancer Quality of Life Study

Objectives:

(1) Evaluate quality of life (QOL) outcomes in head and neck cancer survivors at our institution. (2) Recognize areas of improvement in our head and neck cancer survivors in order to decrease morbidity and mortality.

Methods:

A total of 53 patients completed a 24-question QOL survey, previously validated by Terrell et al. The study was conducted between 2013 and the present day.

Results:

Sixty-two percent were male, and the average age was 64. Patients were on average 1.8 years past their definitive surgery. Thirty-eight percent were current tobacco users and 30% were former tobacco users. Most cases were squamous cell carcinoma (92%) of the oral cavity/oropharynx and hypopharynx/larynx (57% and 30%, respectively). All stages were represented (I: 19%, II: 28%, III: 13%, IV: 34%). Fifty-four percent underwent radiation therapy, and 26% underwent chemotherapy. Overall, patients were satisfied with speech, eating, pain, emotional toll, and overall disturbance (71% ± 27 [SD], 76% ± 19, 80% ± 23, 76% ± 22, and 70% ± 23 respectively). Overall, patients were very satisfied with their head and neck care at our institution (93% ± 12%). Most patients quit using tobacco products after their cancer treatments/diagnosis.

Conclusions:

Overall, most patients were satisfied with pain, speech, eating, emotional impact, and overall disturbance. However, the standard deviation was large. This finding could be related to pooling of all the results. Future studies are planned to evaluate quality of life outcomes based on stage, location, and/or time since surgery.

Retrospective analysis of the impact of HPV status and smoking on mucositis in patients with oropharyngeal squamous cell carcinoma treated with concurrent chemotherapy and radiotherapy

OBJECTIVES

The standard concurrent radiotherapy and chemotherapy regimens for patients with oropharyngeal cancer are highly toxic. Human papillomavirus (HPV)-associated oropharyngeal squamous cell carcinoma (OPSCC) has recently emerged as a distinct biological and clinical entity with improved response to treatment and prognosis. A tailored therapeutic approach is needed to optimize patient care. The aim of our study was to investigate the impact of HPV and smoking status on early toxicities (primarily mucositis) associated with concurrent chemotherapy and radiotherapy in patients with OPSCC.

MATERIALS AND METHODS

We retrospectively evaluated 72 consecutive patients with OPSCC and known HPV status treated with concurrent radiotherapy and chemotherapy at our institution. Treatment-related toxicities were stratified by smoking and HPV status and compared using univariate and multivariate logistic regression.

RESULTS

HPV-positive patients had a 6.86-fold increase in the risk of having severe, grade 3-4 mucositis. This effect was preserved after adjusting for patient smoking status, nodal stage, radiotherapy technique and radiotherapy maximum dose. Additionally, HPV status had significant effect on the objective weight loss during treatment and at three months after treatment. Consistently, non-smokers had a significant 2.70-fold increase in the risk of developing severe mucositis.

CONCLUSION

Risk factors for OPSCC modify the incidence of treatment-related early toxicities, with HPV-positive and non-smoking status correlating with increased risk of high grade mucositis and associated outcomes. Retrospective single-institution studies need to be interpreted cautiously. However, this finding is important to consider when designing therapeutic strategies for HPV-positive patients and merits further investigation in prospective clinical trials.

Age-related changes of hyoid bone position in healthy older adults with aspiration

OBJECTIVES/HYPOTHESIS

Aspiration, the passage of a bolus below the vocal folds, increases morbidity and mortality in the elderly by increasing the risk of aspiration pneumonia and other conditions. We hypothesized that altered position of the hyoid bone associated with aging may negatively affect airway protection during swallowing (i.e., aspiration) in older adults.

STUDY DESIGN

Retrospective study.

METHODS

We re-reviewed computed tomography (CT) scans of the head from 40 older adults (65-80 years old), comprised of 20 aspirators and 20 nonaspirators, obtained from a previous cohort study. In addition, CT scans of the head from 40 young adults (20-40 years old) were retrieved from a medical records database. Three-dimensional reconstruction and 2-dimensional sagittal views were used to measure the distance between the mandible and hyoid bone. Comparisons between age groups, genders, and aspiration status were made.

RESULTS

Older adults had a larger distance between the hyoid and mandible in both latitude and longitudinal positions compared to the young adults. Among older males, there was evidence that the hyoid bone in the aspirators tended to be positioned more posterior compared to the nonaspirators.

CONCLUSIONS

The distance between the hyoid and mandible is increased with aging, and a more posterior position of the hyoid bone is correlated with aspiration in older males. These findings suggest that age-related changes in hyoid bone position may be a component of decreased swallowing safety and aspiration in older adults and warrant further investigation.

LEVEL OF EVIDENCE

N/A.

Improving hydrolysis of food waste in a leach bed reactor

This paper examines the rate of degradation of food waste in a leach bed reactor (LBR) under four different operating conditions. The effects of leachate recirculation at a low and high flow rate are examined with and without connection to an upflow anaerobic sludge blanket (UASB). Two dilution rates of the effective volume of the leach bed reactors were investigated: 1 and 6 dilutions per LBR per day. The increase in dilution rate from 1 to 6 improved the destruction of volatile solids without connection to the UASB. However connection to the UASB greatly improved the destruction of volatile solids (by almost 60%) at the low recirculation rate of 1 dilution per day. The increase in volatile solids destruction with connection to the UASB was attributed to an increase in leachate pH and buffering capacity provided by recirculated effluent from the UASB to the leach beds. The destruction of volatile solids for both the low and high dilution rates was similar with connection to the UASB, giving 82% and 88% volatile solids destruction respectively. This suggests that the most efficient leaching condition is 1 dilution per day with connection to the UASB.

Evaluation of the biomethane potential from multiple waste streams for a proposed community scale anaerobic digester

This paper examines the biomethane potential from organic waste for a proposed community scale anaerobic digester in a rural town. The biomethane potential test is used to assess the suitability of waste streams for biomethane production and to examine the variation in biomethane potential between waste sub-streams. A methodology for accurately estimating the biomethane potential from multiple heterogeneous organic waste substrates is sought. Five main waste streams were identified as possible substrates for biogas production, namely Abattoir waste (consisting of paunch and de-watered activated sludge); cheese factory effluent; commercial and domestic food waste; pig slurry and waste water treatment sludge. The biomethane potential of these waste streams ranged from as low as 99 L CH4 kg VS(-1) for pig slurry to as high as 787 L CH4 kg VS(-1) for dissolved air floatation (DAF) sludge from a cheese effluent treatment plant. The kinetic behaviour of the biomethane production in the batch test is also examined. The objective of the paper is to suggest an optimum substrate mix in terms of biomethane yield per unit substrate for the proposed anaerobic digester. This should maximize the yield of biomethane per capital investment. Food waste displayed the highest biomethane yield (128 m(n)(3) t(-1)) followed by cheese waste (38 m(n)(3) t(-1)) and abattoir waste (36 m(n)(3) t(-1)). It was suggested that waste water sludge (16 m(n)(3) t(-1)) and pig slurry (4 m(n)(3) t(-1)) should not be digested. However, the biomethane potential test does not give information on the continuous operation of an anaerobic digester.

Evaluation of the biomethane yield from anaerobic co-digestion of nitrogenous substrates

This paper examines three substrates for anaerobic co-digestion: abattoir waste; cheese waste and food waste. These substrates were assessed in detail for suitability for biomethane production. Biomethane potential (BMP) assays were carried out in mono and co-digestion for the three substrates and two mixes: T1 (40% abattoir waste; 50% cheese waste and 10% food waste on a wet weight basis) and T2 (30% abattoir waste; 40% cheese waste and 30% food waste). The C:N ratio of both mixes was below optimum. Low levels suggest that the production of free ammonia (NH3) in semi-continuous digestion was of primary concern. Both mixes were digested in a semi-continuous process for 25 weeks. The recommended operating condition for T1 was a loading rate of 3 kg VS mn(-3) day(-1) at a retention time of 23 days. The biomethane yield was 305 L CH4 kg(-1) volatile solids (VS) which was 87% of the BMP value and equivalent to 61% biodegradability. For T2 (with the higher C:N ratio) a higher loading rate of 4kg VS mn(-3) day(-1) at a lower retention time of 15 days was recommended. The biomethane yield was 439 L CH4 kg(-1) VS (99% of the BMP value and 84% biodegradibility). At these conditions, levels of total ammonical nitrogen (TAN) were 4109 and 4831 mg L(-1) for T1 and T2, respectively. These values are on the large side according to the literature. The temperature was reduced to 35 degrees C to minimize toxicity associated with TAN. Ratios of volatile acids to bicarbonate were typically in the range of 0.2-0.3 suggesting stable operation.

Aging-related geniohyoid muscle atrophy is related to aspiration status in healthy older adults

BACKGROUND

Age-related muscle weakness due to atrophy and fatty infiltration in orofacial muscles may be related to swallowing deficits in older adults. An important component of safe swallowing is the geniohyoid (GH) muscle, which helps elevate and stabilize the hyoid bone, thus protecting the airway. This study aimed to explore whether aging and aspiration in older adults were related to GH muscle atrophy and fatty infiltration.

METHOD

Eighty computed tomography scans of the head and neck from 40 healthy older (average age 78 years) and 40 younger adults (average age 32 years) were analyzed. Twenty aspirators and 20 nonaspirators from the 40 older adults had been identified previously. Two-dimensional views in the sagittal and coronal planes were used to measure the GH cross-sectional area and fatty infiltration.

RESULTS

GH cross-sectional area was larger in men than in women (p < .05). Decreased cross-sectional area was associated with aging (p < .05), and cross-sectional area was significantly smaller in aspirators compared with nonaspirators, but only among the older men (p < .01). Increasing fatty infiltration was associated with aging in the middle (p < .05) and posterior (p < .01) portions of the GH muscle. There was no significant difference in fatty infiltration of the GH muscle among aspirators and nonaspirators.

CONCLUSION

GH muscle atrophy was associated with aging and aspiration. Fatty infiltration in the GH muscle was increased with aging but not related to aspiration status. These findings suggest that GH muscle atrophy may be a component of decreased swallowing safety and aspiration in older adults and warrants further investigation.

Surgical therapy of glomus vagale tumors

Lying between the carotid bifurcation and the jugular foramen, glomus vagale tumors share characteristics with paragangliomas of those two structures, such as invasion of the carotid artery, destruction of the skull base, and cranial neuropathies. This capability for local invasion provides a therapeutic challenge with regard to the proper assessment of tumor extent and the selection of appropriate treatment. In order to clarify an approach to the management of glomus vagale tumors, we reviewed a 10-year experience with 15 patients treated for this tumor at the University of Zürich Department of Otolaryngology, using a new system of classification. This system highlights the relative position of a vagal paraganglioma to the jugular foramen and is helpful in designing the proper therapy. Pitfalis in surgical technique, recommended preoperative evaluation, and the roles of balloon occlusion and irradiation in the treatment of these tumors, are discussed.

Lateral orbital/anterior midfacial degloving approach for nasopharyngeal angiofibromas with cavernous sinus extension

A case of nasopharyngeal angiofibroma removed through a modified lateral approach for an infratemporal fossa resection is reported. This modification involved removing the bone of the lateral orbital apex and posterior middle fossa to expose the dura and periorbita and, when combined with a midfacial degloving approach, provided full access to the tumor abutting the cavernous sinus extradurally while preserving middle ear function.

The midfacial degloving procedure for nasal, sinus, and nasopharyngeal tumors

The midfacial degloving approach is more technically involved than a lateral rhinotomy and requires a basic level of proficiency and understanding of closed rhinoplasty incisions and anatomy of the nose, paranasal sinuses, and skull base structures. Current applications of the midfacial degloving procedure have allowed expansion of indications for this technique through the use of complementary endoscopic and subcranial approaches, permitting the exposure and removal of extensive skull base lesions without disfiguring facial incisions. Fundamental in these approaches is the basic midfacial degloving exposure, which is discussed in this article, along with the applications for treatment of skull base lesions.

Endovascular treatment of hemorrhage after tonsillectomy in children

SUMMARY

Endovascular therapy for hemorrhage after tonsillectomy or adenoidectomy is an important adjunct to the definitive treatment of this life-threatening occurrence. We report two cases of hemorrhage after tonsillectomy and/or adenoidectomy and describe the endovascular management of this complication in children.

Preservation of olfaction in anterior skull base surgery

OBJECTIVES/HYPOTHESIS

In selected unilateral tumors and defects of the anterior skull base, the preservation of contralateral olfaction is achievable through a localized subcranial approach without compromising surgical objectives of resection or repair.

STUDY DESIGN

Description of a functional adaptation of anterior skull base surgical techniques through a retrospective patient series.

METHODS

Nine patients underwent anterior skull base surgery for unilateral cribriform plate disease including four malignant and two benign tumors, two encephaloceles, and one iatrogenic cribriform injury with cerebrospinal rhinorrhea. All nine patients consented to a localized subcranial approach to the anterior skull base to preserve the contralateral olfactory nerves. In four patients with benign disease a portion of the ipsilateral nerves was additionally conserved. Postoperative olfaction was assessed objectively with a commercially available smell test. Indications, technique, results, and complications are reported and discussed.

RESULTS

All patients had eradication of disease with preservation of functional olfaction

CONCLUSIONS

Conservation of olfaction is possible in selected cases of anterior skull base surgery when the lesion is unilaterally confined.

Temporal approach for resection of juvenile nasopharyngeal angiofibromas

OBJECTIVE

To describe a lateral preauricular temporal approach for resection of juvenile nasopharyngeal angiofibroma (JNA).

STUDY DESIGN

A retrospective review of five patients with JNA tumors that were resected by a lateral preauricular temporal approach.

METHODS

The medical records of five patients who underwent resection of JNA tumors via a lateral preauricular temporal approach were reviewed, and the following data collected: tumor extent, blood loss, hospital stay, and surgical complications.

RESULTS

Five patients with JNA tumors had resection by a lateral preauricular temporal approach. These tumors ranged from relatively limited disease to more extensive intracranial, extradural tumors. Using the staging system advocated by Andrews et al., these tumors included stages II, IIIa, and IIIb. Four patients (stages II, IIIa, IIIa, and IIIb) who underwent primary surgical excision had minimal blood losses and were discharged on the first or third postoperative day with minimal transient complications (mild trismus, frontal branch paresis, serous effusion, and cheek hypesthesia). The remaining patient (stage IIIb) did well after surgery, despite having undergone preoperative radiation therapy and sustaining a significant intraoperative blood loss. There have been no permanent complications or tumor recurrences.

CONCLUSIONS

A lateral preauricular temporal approach to the nasopharynx and infratemporal fossa provides effective exposure for resection of extradural JNA tumors. The advantages of this approach include a straightforward route to the site of origin, the absence of facial and palatal incisions, and avoidance of a permanent ipsilateral conductive hearing loss.

Evaluation of airway obstruction using virtual endoscopy

OBJECTIVES

This study examines the use of virtual endoscopy (VE) in the evaluation of patients with upper airway obstruction. The utility of VE compared with actual endoscopy was investigated with respect to accuracy of diagnosis and reproduction of endoscopic images.

STUDY DESIGN

A random cohort of 30 patients with various causes of airway obstruction was examined.

METHODS

The computed tomography (CT) data were reconstructed using a proprietary VE software program, FreeFlight, blind to the actual endoscopic findings. The cause of obstruction was identified and compared with actual endoscopic findings. This included 21 patients with airway stenoses, 8 patients with laryngotracheomalacia, 3 tracheal tumors, 2 glottic webs, 5 patients with innominate artery compression, 2 tracheal granulomas, and 7 patients with impaired true vocal cord mobility.

RESULTS

Virtual endoscopic evaluation was accurate in assessing stenosis width and length of fixed airway lesions. Correlation of stenosis shape and contour between actual endoscopy and VE was excellent. The stenosis-to-lumen ratios were compared between VE and actual endoscopy and were found to be within 10% (SD = 8). However, virtual endoscopic evaluation could not illustrate one of the glottic webs, half of the cases of tracheomalacia, or any of the cases of impaired true vocal cord mobility.

CONCLUSIONS

Virtual endoscopy was not as sensitive as actual endoscopy in detecting the cause of airway obstruction that was based on dynamic movement. However, VE was excellent for the measurement and definition of fixed airway lesions.

Benefits of routine maxillectomy and orbital reconstruction with the rectus abdominis free flap

Maxillary defects lead to functional and cosmetic deficiencies, especially with tumor invasion of the orbit and cribriform plate. Additionally problematic is the near-total palatal resection in patients with poor dentition (ie, not useful for anchoring obturators) and the desire for return of deglutition and useful speech. A series of 12 patients is presented in whom a rectus abdominis free flap was used for reconstruction of the palate, maxilla, and/or orbit. Nine of 12 free flaps were used to reconstruct defects involving the maxilla and orbit; all were successful in restoring hard palate continuity and function without the use of an obturator. The remaining 3 patients underwent successful repair of defects involving the orbit and medial maxilla without complication. Four of those 9 patients with palatal reconstruction augmented their dental rehabilitation with either their existing upper denture plate or the use of a cosmetic appliance anchored to their remaining dentition. Objectively, the rectus abdominis myocutaneous free flap proved to be a reliable and expeditious method of restoring function and acceptable cosmesis. We believe this technique should be routinely considered in the reconstruction of these defects.

The effect of endothelial cell growth factor on peripheral nerve regeneration

Neural regeneration after grafting can be unpredictable. In an effort to enhance the return of function after cable grafting, we studied the effects of an angiogenic factor, endothelial cell growth factor (ECGF), on regenerating nerves. Cable grafts on the sciatic nerve were established in 18 rats and treated with ECGF or a control saline solution. At 5 weeks, nerve conduction studies were performed, and the animals were killed for histologic measurements of graft vascularity and axon counts. A significant increase in vascularity was noted in the treated group versus the control group; neither the axon counts nor the nerve conduction velocities differed significantly between the two groups, although the treated group appeared to show improved neural conduction compared with the control group.

Management of nonepidermoid cancer of the larynx

Nonepidermoid cancer of the larynx represents an extremely diverse group of diseases with differing prognoses and rationales of management. With the lack of specificity in symptoms and physical findings, proper and expeditious lesion characterization is therefore dependent on a high index of suspicion by the clinician and accurate consulting histopathology. These neoplasms can be grouped according to cells with secretory, connective tissue, lymphoreticular, or metastatic origins. Based upon this framework, this article discusses the unique aspects of these various diseases that can lead to their diagnosis, along with consideration of management options and prognostic variables.

Desmoplastic malignant melanoma of the oral mucosa. An underrecognized diagnostic pitfall

BACKGROUND

Although cutaneous desmoplastic malignant melanoma (DMM) has been well characterized, those arising from the oral mucosa have been less well defined.

METHODS

We evaluated the clinical and pathologic features of three patients with biopsy-proven DMM examined at the North Carolina Baptist Hospital. Routine hematoxylin and eosin-stained slides were reviewed in all three cases. Sections from all cases were examined immunohistochemically using the avidin-biotin-peroxidase (ABC) technique and employing commercially available antibodies to the following antigens: S-100 protein, HMB-45, NK1C3, and cytokeratin (AE1/AE3). Appropriate positive and negative controls were utilized throughout these procedures. Clinical data were obtained from the patients' medical records.

RESULTS

Age at diagnosis for the three male patients were 42, 64, and 75 years. Anatomically, these neoplasms arose from the left maxillary oral mucosa (two patients) and the vermilion border of the lower lip (one patient). Initial incisional biopsies of all three patients were misinterpreted as desmoid tumor (one patient) and squamous cell carcinoma (two patients), respectively. Histologically, all tumors were poorly circumscribed and composed of fascicles and bundles of spindle-shaped cells with hyperchromatic nuclei and associated with extensive stromal collagenization. Perineural invasion was noted in two tumors. An overlying atypical, intraepidermal melanocytic proliferation was observed in two tumors. Immunohistochemically, all three tumors showed positive immunoreactivity with S-100 protein and vimentin. One tumor also expressed HMB-45. Wide surgical incision was the primary mode of therapy in all patients. One patient also received multiple courses of radiation therapy and chemotherapy. One patient died of widespread metastatic disease.

CONCLUSIONS

DMM of the oral mucosa is a rare, often unrecognized, form of malignant melanoma associated with a fibrosarcoma-like morphologic appearance and abundant collagenization. Meticulous attention to histomorphology and judicious use of immunohistochemical stains will help prevent misdiagnosis.

Effect of intermittent acid and pepsin exposure on burned esophageal mucosa

PURPOSE

To determine if gastroesophageal reflux affects the healing of esophageal mucosa damaged by alkaline substances.

MATERIALS AND METHODS

In a rabbit model, the effects of intermittent acid and pepsin exposure (thereby mimicking gastroesophageal reflux) on post-caustic-burn esophageal mucosa were examined. Exposures were group I (n = 9), sodium hydroxide exposure alone; group II (n = 9), daily acid and pepsin exposure; and group III (n = 8), sodium hydroxide, then daily acid and pepsin exposure. After 3 weeks, the animals were killed and their esophagi examined.

RESULTS

Grossly, specimens in group II appeared normal; specimens in groups I and III were abnormal, displaying some scar tissue, but were not significantly different. Histologically, the differences between groups I and III approached significance. Increased numbers of intraepithelial eosinophils were seen in those specimens exposed to reflux.

CONCLUSIONS

Gastroesophageal reflux may retard the healing of injured esophageal mucosa and should be studied further in an effort to improve the care of patients who sustain alkaline esophageal burns.

Spontaneous cerebrospinal fluid otorrhea from defects of the temporal bone: a rare entity?

Cerebrospinal fluid (CSF) otorrhea is usually associated with a history of trauma or previous surgery. Spontaneous CSF otorrhea is uncommon. When such spontaneous CSF leakage occurs, it may be associated with dural herniation, with the production of conductive hearing loss from impingement on the ossicles. This type of leakage has characteristic findings which, if recognized, can lead to earlier diagnosis and avoidance of complications. A review of the world literature revealed 44 reported cases. This report presents the authors' experience with 12 patients with spontaneous CSF leakage from temporal bone defects. This entity may be more prevalent than is reported. The differential diagnosis and management of CSF otorrhea (secondary to temporal bone defects) are discussed and representative cases are presented.

Gunshot wounds to the mandible and midface: evaluation, treatment, and avoidance of complications

As American society becomes progressively violent, an ever-increasing number of gunshot wounds are being seen across the United States. Particularly challenging are injuries that involve the mandible and midface, not only because of problems with reconstructing bone and soft-tissue defects but also because of emergent problems with airway obstruction and neurovascular compromise. We present 40 cases of gunshot wounds to the mouth, mandible, and maxilla treated at Wake Forest University Medical Center during the past 7 years. The focus of this retrospective analysis is on emergency evaluation and treatment, complications encountered, and operative techniques used for reconstruction. Special emphasis is placed on recognizing and avoiding the complications of these injuries.

Transotic approach to the cerebellopontine angle

The transotic approach to the cerebellopontine angle for resection of tumors invading the internal auditory canal provides superior illumination and exposure for optimal preservation of facial nerve function. Separation of facial nerve from tumor is enhanced with an anterior exposure that allows visualization of the intracranial segment of the nerve before tumor removal without significantly increasing total operative time. Facial nerve grafting or hypoglossal-facial anastomosis may be incorporated into the procedure at the time of tumor resection using the transotic approach. When combined with a musculofascial patch secured to the dural defect, the initial subtotal petrosectomy with eustachian tube and middle ear cleft obliteration generally avoids the complication of an immediate or delayed postoperative cerebrospinal fluid leak. The transotic approach is indicated for tumors up to 2.5 cm in size that are not adherent to the brain stem.

Management decisions in laryngeal carcinoma in situ

Twenty-one patients with laryngeal carcinoma in situ (n = 12) or carcinoma in situ with microinvasion (n = 9) were treated with laser mucosal dissection of the vocal cords and/or superficial laser cordectomy. The normal architecture of the vocal cords was preserved because the depth of vaporization was usually superficial in these early cases. Five patients had recurrence, new tumor, or persistence of abnormal tissue that required additional laser surgical treatments. With a follow-up range of 6 months to 4 years, all patients currently are free of laryngeal abnormality, and no patient has needed open laryngeal surgery or radiation therapy. Transoral endoscopic laser resection of laryngeal carcinoma in situ with or without microinvasion should be the treatment of choice for these early lesions.

Tracheobronchial foreign bodies

A retrospective review of 88 cases of foreign body aspiration was undertaken. The patients ranged in age from 5 months to 73 years; the peak incidences of foreign body aspiration occurred in children less than 3 years of age and in adults older than 50 years. Sixty-one of the 88 patients were male. Physical examination was abnormal in 61% of patients. The most common radiographic abnormality was inspiratory-expiratory abnormality, seen in 27% of patients. Rigid endoscopy under general anesthesia was the preferred method for removal of the aspirated material. Multiple foreign bodies were found in 5% of the patients. Tracheobronchial foreign bodies should, therefore, be strongly suspected in susceptible patient populations who present with a suggestive history, even when no physical or radiographic evidence can be seen. Patients should be carefully examined for multiple foreign bodies at the time of rigid endoscopic removal.

Headache and the primary empty sella syndrome

Otolaryngologists frequently encounter patients with complaints of headaches. On occasion, normal physical examination findings may be accompanied by a roentgenographic enlargement of the sella turcica. In the process of evaluation for an intrasellar neoplasm, an "empty sella" is occasionally discovered. Patients with this condition commonly have headaches, although a cause-effect relationship is controversial. Endocrine and visual disturbances, although rare necessitate periodic evaluation of these patients.