[Prevalence of abnormal mucosal findings in patients in HNO practices]. / Prävalenz auffälliger Schleimhautbefunde bei Patienten in HNO-Praxen.

OBJECTIVE: To date, no secondary prevention program is in place for patients carrying an increased risk for developing head and neck cancer (HNSCC). In terms of successful, long-term curative therapy and increased quality of life, it would be useful to detect such diseases at an early stage. PATIENTS AND METHODS: A total of 370 patients with at least one risk factor such as "smoking", "alcohol", or "reflux disease" and without any symptoms were examined during a 1-year period using standard HNO methods (e. g. endoscopy) for suspicious alterations of the mucosa of the upper aerodigestive tract. RESULTS: In 13 (3.5%) of all 370 cases a biopsy was taken for further diagnosis. Squamous cell carcinoma was found in eight cases, while one further patient was suffering from non-Hodgkin lymphoma. CONCLUSIONS: It is simple and safe to examine patients at risk of developing HNSCC by standard HNO methods. The rate of detected carcinomas is much higher than in former investigations, likely because our survey focused only on patients with specific risk factors.

[Asbestos dust-induced laryngeal carcinoma--a new occupational disease? Current scientific knowledge and social health regulations]. / Asbeststaubverursachtes Larynxkarzinom--eine neue Berufskrankheit? Derzeitige wissenschaftliche Erkenntnisse und sozialrechtliche Vorgaben.

According to the current regulations pertaining to occupational diseases lung cancer and mesothelioma can be compensated as asbestos-related malignomas under certain circumstances. For several years there has been controversial discussion as to whether laryngeal carcinomas can also be caused by occupational asbestos exposure and should therefore be added to the list of occupational diseases. Critical evaluation of the available scientific knowledge with the scope of currently applicable regulations does not warrant adding asbestos-related laryngeal carcinomas to the list of occupational diseases at present. Further investigations are urgently necessary and may possibly bring new insights.

[Imaging superficial skin tumors of the ENT area. High frequency ultrasound in comparison with computerized tomography and magnetic resonance tomography]. / Darstellung oberflächlicher Hauttumoren im HNO-Bereich. Hochfrequenzultraschall im Vergleich mit Computertomographie und Kernspintomographie.

In order to improve the preoperative diagnosis of superficial skin tumors in the head and neck, 32 patients with 42 basal cell carcinomas, squamous cell carcinomas and malignant melanomas were investigated using different imaging techniques. All patients were examined preoperatively with high-frequency ultrasound (HFU), computed tomography (CT) and magnetic resonance imaging (MRI). New high-frequency ultrasonic scanners (15- and 20-MHz) having an axial resolution of 50-90 microns permit visualization of dermal and cartilaginous structures with an anatomical accuracy to a range of 15 mm in tissue. Exact measurement of the skin tumors and their relation to adjacent structures was feasible. Histologically different tumors could be discriminated by their echo-structure in 80% of the cases. CT and MRI provided additional information when the tumor extension perpendicular to the skin exceeded 15 mm. If tumor extension was less than 15 mm, CT and MRI were inferior to high-frequency ultrasound in the diagnosis of superficial skin tumors and did not provide any additional information. The experience reported has shown that high-frequency ultrasound is a valuable tool for preoperative evaluation of superficial skin tumors in terms of tumor extension and possible invasion of functionally and esthetically important adjacent structures. This knowledge can support preoperative planning of possible resections as well as reconstruction and may help to obtain an appropriate informed consent.

[Localized amyloidosis in the area of the head-neck. A retrospective study]. / Lokalisierte Amyloidose im Kopf-Hals-Bereich. Eine retrospektive Studie.

Localized amyloidosis is a benign rare process in the head and neck. From 1972 to 1992, 12 patients with amyloid deposits of the head and neck were treated at the ENT Department of the University of Erlangen-Nürnberg. Negative congo red staining of rectal biopsy specimens established that the amyloidosis was not systemic. Localized amyloidosis appeared as a diffuse grey-to-yellow mass in the nose (n = 1) or larynx (n = 11). In 10 of the 12 cases excision of amyloid was possible with preservation of adjacent functional structures. Two patients refused surgery and underwent only symptomatic treatment with clinical followup investigations. Amyloid deposits completely excised did not recur during a mean postoperative period of 10 years. When not operated, the amyloid tumors showed a slowly progressive growth pattern.

[Minimally invasive treatment of sialolithiasis using extracorporeal shock waves]. / Minimal-invasive Behandlung der Sialolithiasis mittels extrakorporaler Stosswellen.

BACKGROUND: In the past, management of sialolithiasis required surgical extirpation of the afflicted gland, in case the concrements could not be removed by dilatation or dissection of the glandular duct. The aim of the present study was to investigate the safety and efficiency of extracorporeal shockwave lithotripsy of salivary gland stones in men. PATIENTS AND METHODS: 51 patients with symptomatic solitary salivary stones which could not be removed by conservative measures received extracorporeal piezoelectric shockwave treatment. The concrements had a median diameter of 8 (4-18) mm and were located in the submandibular gland (69%) and in the parotid gland (31%). A total number of 72 shockwave treatments (maximum 3 treatments per patient) were performed under continuous sonographic monitoring. RESULTS: In 45 patients (88%) complete fragmentation of the concrements was achieved. Piezoelectric shockwave therapy was tolerated without any need for anesthesia, nor administration of sedatives or analgesics. The only untoward effects resulting from therapy were individual localized petechial hemorrhages after 10 out of 72 treatments (13%) and transient swelling of the gland immediately after shockwave application (2/72, (3%)). Twenty weeks after initial treatment 90% of the patients (46/51) were free of discomfort, and 53% of the patients (27/51) were stone free. The stone clearance rates of patients exhibiting concrements of the parotid gland (81%) were significantly higher than those of patients with stones of the submandibular gland (40%, p < 0.01). Auxiliary measures such as dilatation or dissection of the salivary duct were required only in patients suffering from concrements of the submandibular gland (20%). No long-term damage to the treated salivary gland nor to adjacent tissue structures were noted during the median follow-up period of 9 (1-24) months. CONCLUSION: Extracorporeal piezoelectric shockwave therapy promises to become a safe, comfortable and effective minimal-invasive, non-surgical treatment of salivary stones.

[Scintigraphic imaging of head and neck cancers with 99m technetium (v) dimercaptosuccinic acid. A prospective clinical study]. / Szintigraphische Darstellung von Kopf-Hals-Karzinomen mit 99mTechnetium (v) Dimercaptosuccinic acid. Eine prospektive klinische Studie.

In patients with cervical metastases conventional examination by ultrasound, CT or MRI imaging often fails to identify an unknown primary tumor. Also the retrieval of a recurrent malignancy may be difficult. Scintigraphy, utilizing technetium-99m (v) dimercaptosuccinic acid was chosen for a prospective study in 17 patients to evaluate its properties for imaging metastasizing squamous cell carcinoma of the head and neck. Scintigraphic findings were correlated with the results of clinical examination and conventional imaging techniques. In all cases the primary tumor revealed good uptake of 99mTc(v)DMSA. Manifest cervical metastases could only be imaged in some cases. In future, therefore, 99mTc(v)DMSA scanning may be used for the detection of unknown primary tumors. However, it does not appear helpful in the evaluation of cervical nodes.

Shockwave lithotripsy of salivary duct stones.

Surgical extirpation of the affected gland has been necessary for cases of sialolithiasis in which the stone cannot be removed by dilatation or dissection of the salivary duct. The ability of the piezoelectric lithotripter to deliver shockwaves to a small focus makes extracorporeal shockwave lithotripsy of salivary gland stones potentially safe. Its safety and efficacy have been assessed in 51 patients with symptomatic solitary salivary stones that could not be removed by conservative measures. The stones had a median diameter of 8 (range 4-18) mm and were located in the submandibular gland in 69% of patients and in the parotid gland in 31%. A total of 72 shockwave treatment sessions (maximum 3 per patient) were given under continuous sonographic monitoring. In 45 patients (88%) complete fragmentation (fragments less than or equal to 3 mm) of the concrements was achieved. No patient needed anaesthesia, sedatives, or analgesics. The only untoward effects were localised petechial haemorrhages after 10 (13%) out of 72 treatments and transient swelling of the gland immediately after delivery of shockwave in 2/72 (3%) sessions. 20 weeks after the first session 90% (46/51) of patients were free of discomfort, and 53% (27/51) were stone free. Stone-clearance rate was higher among patients with stones in the parotid gland (81%) than among those with stones of the submandibular gland (40%). Auxiliary measures such as dilatation or dissection of the salivary duct were required only in patients with stones in the submandibular gland (20%). No long-term damage to the treated salivary gland or to adjacent tissue structures was noted during the median follow-up of 9 (1-24) months. Extracorporeal piezoelectric shockwave therapy seems likely to be safe, comfortable, and effective minimally-invasive, non-surgical treatment for salivary stones.

Search for cell culture systems with diverse xenobiotic-metabolizing activities and their use in toxicological studies.

Many toxic effects are not caused by the administered compound itself, but are due to metabolites. All cell types express some xenobiotic-metabolizing enzymes, but levels and patterns are very variable. Critical metabolic steps may occur within the target cell and/or at other sites. This complex situation is difficult to mimic in vitro. The further problem is that cells that are taken into culture tend to rapidly cease the expression of important xenobiotic-metabolizing enzymes. Part of the problem may be solved by the addition of exogenous metabolizing systems, for example, in the form of freshly isolated hepatocytes, crude subcellular preparations, or purified enzymes. In these systems, the plasma membrane of the target cell may act as a barrier for the active metabolite and thereby lead to false negative results. The alternative is the use of metabolically active target cells. We therefore screened 18 cell lines for monooxygenase, cytochrome P-450 reductase, epoxide hydrolase, glutathione transferase, and UDP-glucuronosyl transferase activities. In further studies, IEC-17, IEC-18, and HuFoe-15 cells showed their capabilities of activating a broad spectrum of structurally heterogenous promutagens, as indicated by the induction of micronuclei. These cells, however, were not suited for the study of a more relevant genetic end point, the induction of hereditary functional changes (gene mutations), implying that a compromise had to be made on the level of the toxicodynamics. In the second approach, cDNAs encoding the rat cytochromes P-450IA1 and P-450IIB1, set under the control of a constitutive promoter, were transfected into V79 Chinese hamster cells, which do not express cytochromes P-450 but are ideal target cells for gene mutation assays. The resulting substrains (XEM1, XEM2, XEM3; SD1) stably expressed cytochromes P-450IA1 and P-450IIB1, respectively, and showed the corresponding monooxygenase activities. Aflatoxin B1, cyclophosphamide, dibutylnitrosamine, and benzo[a]pyrene mutated SD1 and/or XEM1 and XEM2 cells, but were inactive in parental V79 cells. The mutagenicity of benzo[a]pyrene 7,8-trans-dihydrodiol was about 1000 times more potent in XEM1 and XEM2 cells than in SD1 and V79 cells. Other promutagens were inactive in V79 as well as in the genetically engineered daughter lines. This system therefore is not yet optimal in general screening for the detection of new mutagens, but appears ideal in the identification of critical xenobiotic-metabolizing enzymes for a given mutagen.