Thyroid gland invasion in total laryngectomy and total laryngopharyngectomy: a systematic review and meta-analysis of the English literature.

BACKGROUND: Advanced laryngeal and hypopharyngeal squamous cell carcinomas carry an inherent risk of invading thyroid parenchyma leading to the incorporation of a hemithyroidectomy or total thyroidectomy as part of a total laryngectomy. In some centres, thyroid gland removal occurs routinely during surgery for T3 and T4 laryngopharyngeal carcinoma. However, the incidence of invasion is low, and therefore, thyroid-sparing surgery must be considered for select cases. OBJECTIVE OF REVIEW: The primary goal of the review is to assess the true incidence of thyroid gland invasion in laryngopharyngeal carcinoma. Utilising this data we aim to identify risk factors and clinical predictors of thyroid gland invasion to facilitate in a more targeted approach in the surgical management of advanced laryngopharyngeal carcinoma. TYPE OF REVIEW: A systematic review and meta-analysis of all published data and review of case series at Newcastle upon Tyne Hospitals (NuTH). SEARCH STRATEGY: MEDLINE (1946-2012) and EMBASE (1980-2012) were searched. EVALUATION METHOD: A single reviewer conducted the systematic review with a follow-up ancestry search. Studies publishing case series of T3 and T4 laryngeal and hypopharyngeal carcinoma treated by total laryngectomy or laryngopharyngectomy and partial or total thyroidectomy, with pathological assessment for thyroid gland invasion rates were selected. Articles published prior to 1977 were excluded due to the advent of whole organ sectioning. RESULTS: The literature search identified 16 studies suitable for inclusion, with 1180 cases. The NuTH case series identified 107 patients. The overall pooled incidence of thyroid gland invasion in 1287 patients is 10.7% (95% CI 7.6-14.2). Patients with primary subglottic tumours (relative risk 7.5; 95% CI 4.3-13.0) and disease extension into the subglottis (relative risk 4.3; 95% CI 2.5-7.2) have a significantly higher relative risk of thyroid gland invasion. Radiorecurrent tumours and hypopharyngeal tumours did not have an increased risk of thyroid gland invasion. CONCLUSION: Advanced laryngeal and hypopharyngeal carcinomas involving the subglottis carry a significantly elevated risk of thyroid gland invasion compared with those that spare this subsite. The overall incidence of thyroid gland invasion is low, and therefore, thyroidectomy should be reserved for cases considered to be at risk as opposed to a being a routine measure for all total laryngectomies.

Rapidly progressive hearing loss occurring over weeks: review of differential diagnoses.

BACKGROUND: Sudden hearing loss, or progressive hearing loss occurring over months to years, are well-established presentations. However, little is described in the medical literature on how to approach patients presenting with a rapidly progressive hearing loss occurring over weeks. This study aimed to evaluate the clinical significance of patients presenting with rapidly progressive hearing loss. METHODS: A case of rapidly progressive hearing loss occurring over 12 weeks is presented. A PubMed literature review was performed to determine the evidence-based differential diagnoses for rapidly progressive hearing loss. RESULTS: Fifteen causes were identified for rapidly progressive hearing loss: intracranial aetiologies (meningioma, lymphoma, metastatic deposit, cavernous angioma, meningitis, superficial siderosis); paraneoplastic syndrome (small cell lung carcinoma, thymoma); inflammatory or autoimmune disorders (autoimmune inner-ear disease, sarcoidosis, vasculitis, Sjögren's syndrome); infective disorders (syphilis, human immunodeficiency virus); and medication-induced causes. CONCLUSION: Rapidly progressive hearing loss should be considered a 'red flag' symptom that warrants urgent action. Most causes are systemic or sinister in nature, and the patient's hearing loss can potentially be reversed.

Sacrifice of the chorda tympani nerve during middle-ear surgery can lead to resolution of dysgeusia.

BACKGROUND: Cholesteatoma often presents with persistent otorrhoea, conductive hearing loss or vestibular dysfunction. Rarely, cholesteatoma can cause dysgeusia if the lesion invades into the chorda tympani nerve. This paper presents an individual with cholesteatoma whose dysgeusia resolved following a mastoidectomy in which the chorda tympani was sacrificed. The current literature was reviewed for explanations behind this phenomenon. CASE REPORT: A previously fit 57-year-old man presented with a 3-month history of persistent otorrhoea and the complaint of a metallic taste in the mouth, and was diagnosed with cholesteatoma. The patient underwent radical mastoidectomy and the chorda tympani nerve was sacrificed. On post-operative review, he reported complete resolution of dysgeusia. CONCLUSION: The sense of taste is mediated by a complex neural network. It is possible that once the diseased chorda tympani is transected, compensation arises from other parts of the network. Sectioning of the chorda tympani could lead to a beneficial outcome in selected patients.

Spontaneous regression of advanced-stage oropharyngeal squamous cell carcinoma.

BACKGROUND: Spontaneous regression is defined as the partial or complete disappearance of a malignant tumour proven by microscopic examination in the absence of any substantial treatment. This paper presents the case of an older woman whose advanced-stage tonsillar squamous cell carcinoma was noted to have spontaneously regressed at seven months. CASE REPORT: A 66-year-old woman presented with a 4-month history of dysphagia and odynophagia in September 2020. An exophytic tumour was seen on the right tonsil; this was diagnosed radiologically and histologically as a squamous cell carcinoma of the tonsils, with tumour-node-metastasis staging of T4aN0M0. The patient received best supportive care. Seven months later, the oropharyngeal lesion had disappeared, with no treatment. Subsequent computed tomography imaging showed radiological resolution of the previously noted right-sided oropharyngeal lesion. CONCLUSION: Several mechanisms of spontaneous regression are discussed. Further studies should review this case in conjunction with other reports of spontaneous tumour regressions, to elucidate underlying mechanisms.

Sialodochitis fibrinosa managed with staged bilateral total parotidectomy.

OBJECTIVE: This paper reports a rare case of a 61-year-old man with sialodochitis fibrinosa. METHODS: Clinical case report and review of current literature. RESULTS: Sialodochitis fibrinosa is a diagnosis of exclusion and in many cases can be managed conservatively. Conservative management failed for this patient and he was managed successfully with staged bilateral total parotidectomy. CONCLUSION: Sialodochitis fibrinosa should be considered as a differential diagnosis of painful bilateral facial swelling. While conservative management is successful for many patients, staged bilateral total parotidectomy may be necessary for full remission of symptoms; the timing of this is crucial to reduce the risk of facial nerve palsy.

Necrotising otitis externa: an unusual cause of cranial nerve palsy in a diabetic haemodialysis patient.

We present an unusual case of necrotising otitis externa (NOE) causing a lower motor neurone facial nerve palsy in a patient with diabetes mellitus and receiving maintenance haemodialysis for end-stage renal disease (ESRD). Pseudomonas aeruginosa is the most common pathogen isolated in NOE, although our case involved the non-typical pathogens Aspergillus flavus and Proteus mirabilis. We discuss the need for diagnostic rigour and the importance of considering atypical infective pathology in patients with ESRD or diabetes mellitus. We review NOE with reference to causative agents, imaging strategies, prognostic indicators and treatment.

A permeabilized cell system identifies the endoplasmic reticulum as a site of protein degradation.

Analysis of the fate of a variety of newly synthesized proteins in the secretory pathway has provided evidence for the existence of a novel protein degradation system distinct from that of the lysosome. Although current evidence suggests that proteins degraded by this system are localized to a pre-Golgi compartment before degradation, the site of proteolysis has not been determined. A permeabilized cell system was developed to examine whether degradation by this pathway required transport out of the ER, and to define the biochemical characteristics of this process. Studies were performed on fibroblast cell lines expressing proteins known to be sensitive substrates for this degradative process, such as the chimeric integral membrane proteins, Tac-TCR alpha and Tac-TCR beta. By immunofluorescence microscopy, these proteins were found to be localized to the ER. Treatment with cycloheximide resulted in the progressive disappearance of intracellular staining without change in the ER localization of the chimeric proteins. Cells permeabilized with the pore-forming toxin streptolysin O were able to degrade these newly synthesized proteins. The protein degradation seen in permeabilized cells was representative of that seen in intact cells, as judged by the similar speed of degradation, substrate selectivity, temperature dependence, and involvement of free sulfhydryl groups. Degradation of these proteins in permeabilized cells took place in the absence of transport between the ER and the Golgi system. Moreover, degradation occurred in the absence of added ATP or cytosol, and in the presence of apyrase, GTP gamma S, or EDTA; i.e., under conditions which prevent transport of proteins out of the ER. The efficiency and selectivity of degradation of newly synthesized proteins were also conserved in an isolated ER fraction. These data indicate that the machinery responsible for pre-Golgi degradation of newly synthesized proteins exists within the ER itself, and can operate independent of exogenously added ATP and cytosolic factors.

Skin cancer knowledge, attitudes, beliefs, and prevention practices among medical students: A systematic search and literature review.

BACKGROUND: As future physicians, medical students will play an important role in the prevention of skin cancers by becoming directly involved in skin cancer prevention education and counseling patients about the hazards of ultraviolet light. OBJECTIVE: We assessed the skin cancer-related knowledge, attitudes, beliefs, and prevention practices reported in previous studies of medical students. METHODS: The search for relevant articles was performed in four electronic databases: PubMed (Medline), Cumulative Index to Nursing and Allied Health, ERIC, and PsycINFO. Studies were included if they met the following criteria: 1) targeted medical students; 2) assessed sun avoidance, sun protection, skin self-examination, and/or indoor tanning behaviors; 3) were published in peer-reviewed journals; and 4) complete data were available for extraction. RESULTS: A total of 21 studies are included in this review. Important findings include moderate-to-high levels of skin cancer knowledge and low levels of both sunscreen and ultraviolet light knowledge. The attitudes and knowledge of medical students reflect a low level of concern with regard to the perceived importance of skin cancer compared with other forms of cancer despite a high level of concern for the importance of skin cancer prevention. Furthermore, this review demonstrated that medical students fail to protect themselves routinely from the sun and have a high interest in tanning bed use. CONCLUSION: This review demonstrates the need to educate medical students about skin cancer and skin cancer preventive behaviors. New strategies and educational campaigns should be developed to communicate better information on skin cancer morbidity, mortality, and prevention to medical students. This will pay dividends by improving the practice of these future physicians in all specialties.

Organisation and provision of head and neck cancer surgical services in the United Kingdom: United Kingdom National Multidisciplinary Guidelines.

This is the official guideline endorsed by the surgical specialty associations involved in the care of head and neck cancer patients in the UK. This paper summarises the current state of play in the organisation and provision of head and neck cancer surgical services in the UK.

Self-retaining retractors in head and neck surgery.

The Norfolk and Norwich retractor is a vital tool in head and neck surgery. It is of great aid in training junior surgeons and has become an integral part of the standard neck dissection instrument set in our unit. This retractor enables good exposure of the carotid sheath, its atraumatic blunt tip retracting the carotid sheath without damage. It makes a single skin incision for neck exposure possible, rather than a Y, T or wine glass incision, avoiding a three-point junction, especially in the post-irradiated neck. In thyroid surgery it reduces the need for manual retraction thereby relieving the assistant surgeon and enhancing the quality of the learning experience.

Deterioration of giant cell arteritis with corticosteroid therapy.

BACKGROUND: Failure of response of giant cell arteritis (GCA) to corticosteroid therapy has invariably been attributed to the delay in diagnosing the disease or the use of inadequate corticosteroid dosage. Following our observation of progressive deterioration following the introduction of prednisolone use in a patient, we examined the possibility that worsening of the condition might be due to corticosteroid therapy rather than coincidence. OBJECTIVE: To determine whether corticosteroid therapy may exacerbate GCA. DESLGN: Case report and an analysis of similar cases reported in the medical literature. PATIENT: A 64-year-old man had a 3-month history of headache, night sweats, malaise and general weakness, and anorexia and weight loss and a more recent history of jaw claudication, dysphagia, and hoarseness. Clinical findings included prominent temporal arteries with absent pulsation, abnormal saccades to the right, and eyelid retraction. Laboratory findings included an elevated erythrocyte sedimentation rate and platelet count. Results of a biopsy of the temporal artery confirmed GCA. Magnetic resonance imaging scans showed ischemic cerebellar lesions and a mature infarct in the left anterior occipital, posteroparietal region. Following corticosteroid therapy commencement, the patient's condition deteriorated steadily for 5 days with clinical signs suggestive of an evolving vertebrobasilar stroke. Following treatment with high-dose intravenous dexamethasone sodium phosphate and heparin sodium, his symptoms improved. DATA SOURCES: The review included analysis of autopsy-based reports in which clinical details are provided and clinical reports in which major visual or cerebral complications are described. Significant complications occurred in many cases shortly following the introduction of corticosteroid therapy. In many of these cases, the symptoms indicated that GCA had been present for a significant period prior to corticosteroid therapy. CONCLUSIONS: Progressively evolving occlusive strokes may occur following corticosteroid therapy in patients with GCA. In cerebrovascular complications, vascular occlusion occurs at sites of active vasculitis, usually within the vertebrobasilar system. It is not certain that the worsening of the condition following corticosteroid therapy is always coincidental, and an alternative possibility, namely a functional relationship between the initiation of corticosteroid therapy and clinical deterioration, should be borne in mind.

Fibrin glue achieves hemostasis in patients with coagulation disorders.

Fibrin glue (FG), made with highly concentrated human fibrinogen and clotting factors, was used to achieve parenchymal organ hemostasis in patients with disordered coagulation secondary to massive transfusion, chronic disease, and disseminated intravascular coagulation; it was effective in controlling liver hemorrhage in seven patients and in the performance of a splenorrhaphy in one other patient. The coagulation profile was grossly abnormal in all patients, and the mean +/- SD intraoperative blood loss was 5.1 +/- 4.2 L; patients received 14 +/- 10 U of blood perioperatively. The amount of FG required to achieve hemostasis varied directly with the extent of injury and intraoperative blood loss (r = .84), and all patients with a blood loss greater than 4 L required at least 25 mL of FG to stop bleeding. Two patients died postoperatively secondary to cardiac arrest and adult respiratory distress syndrome. Because FG does not depend on adequate platelet or clotting factor levels to be effective, it is especially useful in patients with parenchymal organ hemorrhage and disordered coagulation.

Characterization of human middle ear mucus glycoprotein in chronic secretory otitis media (CSOM).

Middle ear effusion was obtained from children with chronic secretory otitis media undergoing myringotomy. The effusions contained about 120 mg/ml non-dialysable solids, of which 18-31% was mucus glycoprotein. The purified mucus glycoprotein had a composition characteristic of other mucus glycoproteins. Amino acid analysis of the glycoprotein indicates a protein core consisting of glycosylated regions resistant to proteolysis and non-glycosylated regions susceptible to proteolysis. Analysis of the mucus glycoprotein by gel filtration on Sepharose 2B showed that reduction caused a decrease in hydrodynamic size and proteolysis caused a further decrease. The difference was confirmed by sedimentation coefficient and viscosity measurements. The reduced glycoprotein had an intrinsic viscosity of 0.113 ml/mg and an S0(20) of 15.2S compared to a value of 0.018 ml/mg and 9.6S for the proteolytically digested glycoprotein. These results suggest a model for this middle ear mucus glycoprotein, in which the native glycoprotein is a large molecular mass polymer maintained by disulphide bridges. These disulphide linked glycoprotein units are broken down into smaller units by proteolysis. The mucus glycoprotein could not be purified completely free from low molecular mass components. A glycoprotein, susceptible to proteolysis Mr 28,000-33,000 co-fractionates with the major high molecular mass mucus glycoprotein.

Altered MUC1 and MUC2 glycoprotein expression in laryngeal cancer.

The purpose of this study was to determine whether mucin expression is altered in laryngeal cancer. MUC1 and MUC2 mucin expression was examined in biopsy specimens from 80 patients that comprised 23 laryngeal dysplasias, 36 laryngeal carcinomas, and 21 normal larynx control specimens. High MUC1 expression was found in all 3 groups (P = 0.689, Fisher exact test). However, significantly higher levels of MUC2 expression were detected in carcinomas compared with dysplasias and control specimens (P = 0.009, Fisher exact test). Altered MUC2 expression may be an important step in carcinogenesis in laryngeal cancer.

The role of thorax imaging in staging head and neck squamous cell carcinoma.

The overall survival rate for patients with head neck squamous cell carcinoma remains disappointingly static despite improved locoregional control. This has been attributed to the development of distant metastases and second primary malignancies in these patients, a large proportion of which occur in the thorax. We retrospectively analysed the incidence of thoracic malignancies in 138 patients presenting with newly diagnosed (n = 107) or recurrent (n = 31) cancer of the head and neck over a 4-year period. All 138 patients had undergone both computerised tomography of the thorax (CT) and conventional chest radiography within one month of presenting with biopsy proven squamous cell carcinoma. Seventeen percent of these were found to have simultaneous thoracic malignancies. CT thorax was more sensitive in detecting simultaneous thoracic malignancies compared with standard chest X-ray (24/138 versus 9/138, odds ratio of 3:1 in favour of CT). All thoracic malignancies detected by chest X-ray were also detected by CT thorax. Patients presenting with recurrent tumors were significantly more likely to have simultaneous thoracic malignancies than those with newly diagnosed cancer (11/31 versus 13/107, chi2 test with Yates correction, chi2 = 4.66, p = 0.03). The primary site (laryngeal, oral or pharyngeal) or presence of nodal disease did not have an effect on the incidence of simultaneous thoracic malignancies. The presence of distant metastases and second primary malignancies has major implications in the management and prognosis of patients presenting with head and neck squamous cell carcinoma, with a large proportion of such patients succumbing to their disease within one year of diagnosis. As CT scanning of the thorax was a more effective screening investigation than standard chest X-ray in the detection of simultaneous thoracic malignancy, we recommend it for use in the staging of patients presenting with cancer of the head and neck.

Mathematical models of central pattern generators in locomotion: I. Current problems.

As a background for subsequent studies of mathematical models of central pattern generators in locomotion (Stafford & Barnwell, 1985a, b) relevant aspects of the literature on locomotion are reviewed, concepts of locomotion discussed, and extant models considered. Advantages and disadvantages of present models are discussed, and the need for mathematical models is emphasized. It is shown that realistic models of pattern generation in locomotion must take numerous factors into account, including phases of step cycle, muscle sequencing, gait and interlimb coordination, initiation and cessation of locomotion, and many aspects of neuromuscular control and function.

Mathematical models of central pattern generators in locomotion: II. Single limb models for locomotion in the cat.

Three mathematical models of central pattern generation for locomotion in the single limb of the cat are presented. In each model, the activities in populations of neurons controlling limb joint flexors and extensors are described by a system of nonlinear differential equations. Each solution of the system for a different set of parameters corresponds to a simulation of some gait of the cat. Model I is based on unit generators for each limb joint muscle group and assumes that flexors inhibit their paired extensors, but not vice-versa. Model IIa assumes that flexors and extensors are mutually inhibitory, but that only the flexors have inherent oscillatory capability. Model IIb assumes flexors and extensors are mutually inhibitory and that both flexors and extensors have oscillatory capability. The properties of each of these models are explored, compared and contrasted, and discussed in relation to the experimental literature. All three models are shown to be capable of generating patterns consistent with various stepping rates of the cat and to show appropriate muscle sequencing and flexor-extensor interactions. Further, all three models exhibit smooth initiation and termination of stepping. However, Model I seems to provide a more parsimonious account of producing changes in stepping rate and is preferred, therefore, over models IIa and IIb.

Mathematical models of central pattern generators in locomotion: III. Interlimb model for the cat.

Possible neural connective patterns and functions with respect to interlimb coordination are studied theoretically with a mathematical model of the central pattern generating system for cat locomotion. Activities in populations of neurons controlling limb joint flexors and extensors in all four limbs are represented by a system of nonlinear differential equations. Solutions of the system for various parameter values simulate various gaits of the cat. The model is shown to be capable of generating all gaits of the cat and accounting for corresponding phase changes in interlimb coordination. The model also exhibits smooth changes of gait, and smooth initiation and termination of stepping. Further, within each limb, muscle sequencing, step cycle phases, and flexor-extensor interactions can be studied. The model suggests that one of the simplest mechanisms for a central command system to change the gait is via inhibition of specific interlimb propriospinal pathways. In a final section, properties of both proposed single limb and interlimb models are reviewed with specific reference to planning future experimental and theoretical studies.

Post cricoid lymphangioma.

A 69-year-old female patient presented with symptoms characteristic of globus pharyngeus and barium swallow examination was normal. Her symptoms persisted and pharyngoscopy was undertaken; a post-cricoid polyp was found and removed. Histological examination revealed this to be a lymphangioma. Histological appearances, pathogenesis and treatment are discussed. The case illustrates that persisting symptoms presenting as globus pharyngeus should be further investigated to exclude rare lesions.