Recurrence after primary salivary gland carcinoma: Frequency, survival, and risk factors.

BACKGROUND: Primary salivary gland carcinomas (SGC) are rare neoplasms that present therapeutic challenges especially in recurrent tumors. The aim of this study was to investigate the incidence and distribution of tumor recurrence, associated risk factors, and survival. METHODS: This analysis includes data from 318 patients treated for SGC between 1992 and 2020. Survival analysis was performed using the Kaplan-Meier method. Univariate and multivariate analyses were used to identify risk factors associated with recurrence. RESULTS: 21.7% of the patients developed recurrent disease after a mean of 38.2 months. In multivariate analysis, positive-resection margins, vascular invasion, and tumor localization in the submandibular gland and small salivary glands were independent factors for recurrence. The 5-year overall survival was 67%, the 5-year disease-free survival was 54%. CONCLUSION: Tumor recurrence in SGC occurred in one out of five patients. In highly aggressive entities and patients with risk factors, treatment intensification should be considered.

Incidence and clinical outcome of primary carcinomas of the major salivary glands: 10-year data from a population-based state cancer registry in Germany.

PURPOSE: The aim of this project was to provide an overview of the epidemiology of primary salivary gland carcinomas (SGC) in terms of incidence, distribution of clinicopathological features and survival in one of the largest cancer registries in Europe. METHODS: Data were collected from patients with SGC of the major salivary glands registered in the population-based state cancer registry (Landeskrebsregister LKR) in North Rhine-Westphalia (NRW), Germany from 01/01/2009 to 12/31/2018. Age standardization of incidence was performed and relative survival estimates were computed by sex, histological group, age group and T-, N-, and M-stage. RESULTS: A total of 1680 patients were included in this analysis. The most frequent tumor localization was the parotid gland (78%). Adenocarcinoma (not otherwise specified) was the most common tumor entity (18.5%). Most tumors were found in stages T1-T3 (29% T1; 29% T2; 28% T3). The age-standardized incidence rate (ASR) for SGC was 0.65/100,000 and remained stable during the observation period. There was an age-dependent incidence increasing especially from the age 70 years and onwards. The overall 5-year relative survival (RS) for all patients with SGC was 69.2%. RS was 80-95.6% for T1-2 stage tumors, 60.3% for T3, 47.3% for T4 stage, 87.4% for N0 and 51.2% for N1-2, 74.4% for M0 and 44.9% for M1. CONCLUSION: Age-standardized incidence for SGC has been stable for the observed 10-year period. Smaller tumors and those without lymph node or distant metastases had a better RS than more advanced tumors.

Expression of Mucins in Different Entities of Salivary Gland Cancer: Highest Expression of Mucin-1 in Salivary Duct Carcinoma : Mucin-1 - highest expression in Salivary Duct Carcinoma.

Therapeutic options for advanced salivary gland cancer (SGC) are rare. Therefore, it was the aim of this study to investigate the extent and intensity of Mucin-1 (MUC1), Mucin-16 (MUC16), and Mucin-5AC (MUC5AC) as potential molecular targets using immunohistochemistry. The medical records of all patients who underwent primary surgery for salivary gland cancer with curative intent in a tertiary referral center between 1990 and 2018 were reviewed. Immunohistochemical staining for MUC1, MUC16, and MUC5AC was performed for all patients with sufficient formalin-fixed paraffin-embedded material, and a semi-quantitative combined score derived from the H-score for the cytoplasmatic, the membranous and the apical membrane was built for the most common entities of SGC. 107 patients with malignancies of the parotid (89.7%) and the submandibular gland (10.3%) were included. The most common entities were mucoepidermoid carcinoma (MuEp; n = 23), adenoid cystic carcinoma (AdCy; n = 22), and salivary duct carcinoma (SaDu; n = 21). The highest mean MUC1 combined score was found in SaDu with 223.6 (±91.7). The highest mean MUC16 combined score was found in MuEp with 177.0 (±110.0). The mean MUC5AC score was low across all entities. A higher MUC1 combined score was significantly associated with male gender (p = 0.03), lymph node metastasis (p < 0.01), lymphovascular invasion (p = 0.045), and extracapsular extension (p = 0.03). SaDu patients with MUC16 expression showed a significantly worse 5-year progression-free survival than those without MUC16 expression (p = 0.02). This is the first study to give a comprehensive overview of the expression of MUC1, MUC16, and MUC5AC in SGC. Since advanced SGCs lack therapeutic options in many cases, these results warrant in vitro research on therapeutic targets against MUC1 in SaDu cell lines and xenograft models.

Analysis of smoking behaviour in patients with peritonsillar abscess: a prospective, matched case-control study.

OBJECTIVE: Smoking is purported to increase the risk of peritonsillar abscess formation, but prospective data are needed to confirm this hypothesis. This prospective study aimed to identify this correlation. METHODS: Fifty-four patients with peritonsillar abscess were prospectively asked about their smoking behaviour using a questionnaire that was designed and approved by the Robert Koch Institute (Berlin, Germany) to analyse smoking behaviour in epidemiological studies. Afterwards, a consecutive control group (without peritonsillar abscess), matched in terms of age and gender, was surveyed using the same questionnaire. A classification of smoker, former smoker and non-smoker was made, and the numbers of pack-years were calculated and compared. RESULTS: Statistical analysis of both groups revealed a significant correlation between peritonsillar abscess and smoking experience (p = 0.025). Moreover, there were significantly fewer non-smokers in the non-peritonsillar abscess group (p = 0.04). The number of pack-years was higher in the peritonsillar abscess group (p = 0.037). CONCLUSION: There is a statistically significant association between peritonsillar abscess and smoking.

Patient's perspective on long-term complications after superficial parotidectomy for benign lesions: Prospective analysis of a 2-year follow-up.

OBJECTIVE: Evaluation of patients' perspective on long-term complications after superficial parotidectomy for benign lesions. DESIGN: A prospective nonrandomized controlled multicenter study. SETTING: Three university-based tertiary referral centers (Departments of Otorhinolaryngology of Cologne, Jena and Giessen; all in Germany). PARTICIPANTS: 130 adult patients, who underwent a primary superficial parotidectomy for benign tumors of the parotid gland, were consecutively included from 09/2010 to 05/2012. 61 patients completed every follow-up examination. MAIN OUTCOME MEASURES: Complications were evaluated using the validated German-language questionnaire Parotidectomy Outcome Inventory 8 at six, 12 and 24 months after surgery. Pain intensity was assessed on a numeric rating scale (NRS) at each follow-up visit. RESULTS: At 6 months after surgery, 90% characterized hypoesthesia as the most disturbing problem, followed by fear of revision surgery (57%) and scar (56%). Facial palsy (14%) posed the minor problem. Hypoesthesia improved significantly during the follow-up period (all P < .05), but still posed a problem for 78% of the patients after 2 years. Pain, which initially bothered 53% of the patients, significantly decreased, whereas impairment due to Frey's syndrome significantly increased during the follow-up (6 vs 24 months; P = .002 and P = .001, respectively). Scar, substance loss, xerostomia, facial palsy, and anxiety affected patients with unvarying severity during the 2 years (all P > .05). CONCLUSIONS: From patients' perspective, sensation loss posed the major subjective problem after superficial parotidectomy. Appearance of the scar, and fear of revision surgery impaired more than 50% of the patients in their daily life without significant improvement during the 2 years postoperatively. Although superficial parotidectomy is a highly standardized and safe procedure, limited parotidectomy for proven benign parotid salivary gland neoplasms is more likely to result in patients with minimal or no displeasing complications.

Sequelae of carpal tunnel surgery: rationale for the design of a surgical approach.

The sequelae of carpal tunnel surgery were reviewed and were presumed to be associated with the linear vertical section of the transverse carpal ligament because this was the common element in the reported series. The authors adopted a modified approach, substituting a parabolic incision that left a protective flap of the ligament to cover the structures within the tunnel in the area of maximum convexity of the wrist. The results from a recent series of 100 cases were contrasted with a control series of 770 previous cases. Untoward postoperative sequelae were significantly reduced through this modified approach. The improved results, the authors conclude, were attributable to a reduction of pressure within the carpal tunnel, while avoiding the wide gaping of the tunnel space that is associated with vertical incisions, which may allow an anterior displacement of the median nerve and flexor tendons between the cut ends of the transverse carpal ligament and sometimes result in a continuous scar through the skin.

The Water Pressure Integrity Test--a new integrity test for hydrophobic membrane filters.

Sterilizing grade hydrophobic filters are used for the sterile filtration of gases in pharmaceutical and biological applications. Until now the integrity of these membrane filters and their ability to retain bacteria, has been correlated to a solvent based nondestructive integrity test. Current methods use solvents to wet the membranes in order to perform bubble point and diffusion integrity tests. Solvent based integrity tests make it difficult to test in situ following sterilization because of the risk of downstream solvent contamination. A newly developed method, the Water Pressure Integrity Test (WPIT), allows for the integrity testing of hydrophobic filters eliminating the problems associated with traditional test methods employing solvents. A prime advantage of WPIT is that it may be performed in situ post sterilization without any downstream manipulations. The test has been directly correlated to the retention of bacterial challenges. Data will be provided to show the reliability and sensitivity of this easy to perform test.

Molecular aspects of microbial ice nucleation.

Certain organisms nucleate the crystallization of ice. This requires a small volume of water to be induced, probably by lattice-matching with a solid template, to form an 'ice embryo'--a region sharing at least some of the characteristics of macroscopic ice. It is of particular interest to understand the structure and function of biological structures capable of lattice-matching (or otherwise inducing a quasi-crystalline state). Some strains of the Gram-negative eubacterial genera Erwinia, Pseudomonas, and Xanthomonas, and the mycobionts of certain lichens, display ice-nucleating activity. In bacteria, the activity is conferred by a protein that contains three nested periodicities of repetition, which probably reflects a hierarchy of three motifs of structural repetition. Thus the tertiary structure of the ice-nucleation protein is likely to be regular, consistent with the expectation of its forming a template for lattice-matching. Even within a clonal culture, the nucleating sites formed by bacteria and lichens vary considerably in the threshold temperatures at which they display activity; this indicates wide variations in either the size of the template, or its structural regularity, or both. However, ice-nucleating sites of lichen and bacterial origin are clearly differentiated by their sensitivities to experimental treatments.

Rates of assembly and degradation of bacterial ice nuclei.

The kinetics of ice-nucleus assembly from newly synthesized nucleation protein were observed following induction of nucleation gene expression in the heterologous host Escherichia coli. Assembly was significantly slower for the small proportion of ice nuclei active above -4.4 degrees C; this was consistent with the belief that these nuclei comprise the largest aggregates of nucleation protein. The kinetics of nucleus degradation were followed after inhibiting protein synthesis. Nucleation activity and protein showed a concerted decay, indicating that most of the functional ice nuclei are in equilibrium with a single cellular pool of nucleation protein. A minority of the ice nuclei decayed much more slowly than the majority; presumably their nucleation protein was distinct either by virtue of different structure or different subcellular compartmentalization, or because of its presence in a metabolically distinct subpopulation of cells.

Clustering of ice nucleation protein correlates with ice nucleation activity.

Antibodies raised against a synthetic peptide specifically detect ice nucleation proteins from Pseudomonas species in Western blots. In immunofluorescent staining of whole bacteria, the antibodies reveal the protein in clusters, as indicated by patches of intense fluorescence in Escherichia coli cells heterologously expressing Pseudomonas ice nucleation genes. The abundance, size, and brightness of the clusters vary considerably from cell to cell. Their varying sizes may explain the variability in activity of bacterial ice nuclei. Growth at lower temperatures produces more ice nuclei, and gives brighter and more frequent patches, than growth at 37 degrees C. The observed clustering may thus reflect formation of functional ice nucleation sites in vivo. The presence of ice nucleation protein in clusters is also correlated with alterations in cell morphology.

Bacterial ice-nucleation proteins.

Certain bacteria possess proteins that enable them to nucleate crystallization in supercooled water. These ice-nucleation proteins are thought to produce templates for the assembly of very small seed crystals of ice. The proteins from different species have related, internally repetitive primary structures, which may be directly responsible for aligning the water molecules of the seed crystal.

Nonlinear relationship between concentration and activity of a bacterial ice nucleation protein.

The expression level of an ice nucleation gene (inaZ) was varied in Escherichia coli to observe the relationship between activity and gene product. The ice nucleation activity increased as the 2nd to 3rd power of the membrane concentration of the inaZ gene product, implying that molecules of InaZ protein interact cooperatively in groups of two to three at the rate-limiting step of ice nucleus assembly. The 2nd to 3rd power relationship was independent of the threshold temperature at which ice nucleation was measured and was consistent over a 500-fold range of protein concentration. Such a relationship indicates that the same rate-limiting step must be common to the formation of ice nuclei displaying all the various threshold temperatures within a bacterial population. Observations of Pseudomonas syringae, expressing the inaZ gene at various levels, were consistent with a similar relationship and hence a similar mechanism of ice nucleus assembly in Pseudomonas.

Surgical management of extreme lateral lumbar disc herniations: review of 138 cases.

Extreme lateral disc herniations in the authors' series account for 10% of all lumbar herniations; 80% occurred at the L3, L4 and L4, L5 interspaces. The authors review the clinical findings in 138 patients and point to the characteristic features of the clinical syndrome. They compare the accuracy of various diagnostic studies and conclude that computed tomography is highly accurate and should be used before other diagnostic studies. Discography is still helpful as a confirmatory study in some cases, whereas myelography is particularly useful in disclosing other associated lesions. Analysis of the operative series revealed a high percentage of extruded fragments (60%) and a significant number of double herniations on the same side and at the same level (15%). These two findings may respectively preclude chemonucleolysis and microsurgery from the surgical management of extreme lateral herniations. Double herniations explain some discrepancies in the clinical picture and are emphasized as a potential source of error in diagnosis. The surgical technique allows exploration for herniations within the intervertebral canal as well as for extraforaminal herniations without sacrifice of the facet. Operative results are presented.

Immunological characterization of ice nucleation proteins from Pseudomonas syringae, Pseudomonas fluorescens, and Erwinia herbicola.

Antibodies were raised against the InaW protein, the product of the ice nucleation gene of Pseudomonas fluorescens MS1650, after protein isolation from an Escherichia coli clone. On Western blots (immunoblots), these antibodies recognized InaW protein and InaZ protein (the ice nucleation gene product of Pseudomonas syringae S203), produced by both E. coli clones and the source organisms. The InaZ protein appeared in P. syringae S203 during stationary phase; its appearance was correlated with the appearance of the ice nucleation-active phenotype. In contrast, the InaW protein occurred at relatively constant levels throughout the growth phases of P. fluorescens MS1650; the ice nucleation activity was also constant. Western analyses of membrane preparations of P. syringae PS31 and Erwinia herbicola MS3000 with this antibody revealed proteins which were synthesized with development of the nucleating phenotype. In these species the presence or absence of the nucleating phenotype was controlled by manipulation of culture conditions. In all nucleation-positive cultures examined, cross-reacting low-molecular-weight bands were observed; these bands appeared to be products of proteolytic degradation of ice nucleation proteins. The proteolysis pattern of InaZ protein seen on Western blots showed a periodic pattern of fragment sizes, suggesting a highly repetitive site for protease action. A periodic primary structure is predicted by the DNA sequence of the inaZ gene.

Conserved repeats in diverged ice nucleation structural genes from two species of Pseudomonas.

Sequence analysis shows that an ice nucleation gene (inaW) from Pseudomonas fluorescens is related to the inaZ gene of Pseudomonas syringae. The two genes have diverged by many amino acid substitutions, and have effectively randomized the third bases of homologous codons. By reference to their potential for change, it is shown that certain conserved features must have been maintained by selection pressure. In particular, their conservation of internal sequence repetition, with three orders of repeat periodicity in each gene, suggests that the pattern of repetition is significant to the gene products' function. We propose models for the structure of the gene products in which each order of periodicity would be required for the nucleation function.

Identification and purification of a bacterial ice-nucleation protein.

The protein product of a gene (inaZ) responsible for ice nucleation by Pseudomonas syringae S203 has been identified and purified after overexpression in Escherichia coli. The amino acid composition and the N-terminal sequence of the purified, denatured protein corresponded well with that predicted from the sequence of the inaZ gene. The product of inaZ was also found to be the major component in preparations of ice-nucleating, proteinaceous particles, obtained after extraction with and gel filtration in a mixture of urea and the nondenaturing detergent octyl beta-D-thioglucopyranoside. The activity of these preparations in the absence of added lipid implies that the protein participates directly in the nucleation process.