Laryngeal schwannoma: case report and literature review

Neurogenic tumours of the larynx, particularly schwannomas are rare. We report a case report of a schwannoma in a 30-year-old woman which was excised endoscopically. The aim of this paper is to highlight this rare condition and management options to the otolaryngological community.

Impact of different pH thresholds for 24-hour dual probe pH monitoring in patients with suspected laryngopharyngeal reflux

OBJECTIVES

The gold standard test for laryngopharyngeal reflux is 24-hour pH monitoring, which determines the reflux area index with a pH threshold of less than four (i.e. the reflux area index four). However, refluxed pepsin is able to cause laryngeal injury at pH levels above five.

STUDY DESIGN

Prospective study.

MATERIALS AND METHODS

In order to establish normative values for a reflux area index with a pH threshold of less than five (i.e. the reflux area index five), 29 healthy volunteers underwent pH monitoring. In 45 patients with suspected laryngopharyngeal reflux, reflux area index four and reflux area index five were determined by pH study.

RESULTS

In healthy volunteers, the reflux area index five was 72.6 (95th percentile). In 29 of 44 patients, laryngopharyngeal reflux was diagnosed due to a reflux area index four of greater than 6.3. However, the reflux area index five revealed laryngopharyngeal reflux in six more patients.

CONCLUSIONS

For exact analysis of pH monitoring results, two pH thresholds (less than four and less than five) must be considered. Further studies with a larger number of healthy volunteers are necessary in order to reveal normative values for the reflux area index five parameter.

Ertaubung bei Wiskott-Aldrich-Syndrom

INTRODUCTION

The Wiskott-Aldrich-syndrome belongs to the phakomatoses. The hereditary transmission happens x-chromosomal recessive in the domain of Xp 11.3-Xp 11.22. Clinical evidence for that is given by thrombocytopenia, an eczema and a weakness of the immune system with a subsequent increased risk of frequent infections and a predisposition for a malignancies. A further characteristic of that disease is recurrent otitis media as described by Aldrich in 1954.

PATIENT

The case--as described above--is about a 28-year-old male patient developing an acute deafness on the left ear while he has been suffering from a surditas on the right ear for 5 years. 8 years ago a splenectomy was made, because of persistent thrombocytopenia. An additional clinical characteristic was a hemiballism, arising after a thalamusbleeding 5 years ago, a both-sided vestibular failure concerning both that has been existing for 2 years, as well as a maculopathia with a highly reduced visus on both sides.

CONCLUSIONS

The deafness arising in patients suffering from the Wiskott-Aldrich-syndrome represents a so far not described symptom of that illness.

Trends in laryngopharyngeal reflux: a British ENT survey

There is a lot of scepticism surrounding laryngopharyngeal reflux (LPR). Symptoms such as globus pharyngeus, constant throat clearing, chronic cough, idiopathic hoarseness, catarrh and choking episodes may be reflux-related. The aim of this survey was to highlight current treatment trends in LPR. Questionnaires were emailed to 260 members of the British Academy of Otolaryngology-Head and Neck surgery (BAO-HNS). Survey recipients were asked about type, duration and dose of antireflux treatment and length of follow-up appointments, if any. Finally, they were asked about awareness of any reflux symptom and reflux sign questionnaires. Survey response rate was 60%. The vast majority of the otolaryngologists surveyed believe in laryngopharyngeal reflux (90%) and more than 50% prescribe proton pump inhibitors (PPIs). The preferred duration of treatment is 2 months (37%). Only a minority will prescribe PPIs for 6 months or more. Most otolaryngologists will give the standard GORD dose (70%) (once daily) and only a few (20%) will prescribe more aggressive and prolonged doses. The commonest symptoms for which proton pump inhibitors are prescribed are globus (73%), followed by choking episodes (66%) and chronic cough (62%). If LPR is suspected, most of the otolaryngologists will follow-up the patients (61%) and approximately one third (31%) will discharge them back to the general practitioners. Only eight-percent 8% will refer to gastroenterologists. The three commonest laryngoscopic signs that makes them suspect LPR are erythema of the arytenoids (86%) or the vocal cords (57%) and granulomas (42%). The majority of the otolaryngologists (94%) do not use popular questionnaires such as the RFS or RSI. Despite the controversy surrounding laryngopharyngeal reflux, our results suggest that the majority of the otolaryngologists surveyed believe in LPR and attempt to treat it. Interesting findings are: the duration of treatment, the doses used, the length of follow-ups or the lack of, and the fact that the majority does not request any specific diagnostic tests. "symptoms and signs" questionnaires are rarely used.

‘Complementary ENT’: a systematic review of commonly used supplements

Objective:

To assess the evidence surrounding the use of certain complementary supplements in otolaryngology. We specifically focussed on four commonly used supplements: spirulina, Ginkgo biloba, Vertigoheel® and nutritional supplements (cod liver oil, multivitamins and pineapple enzyme).

Materials and methods:

A systematic review of the English and foreign language literature. Inclusion criteria: in vivo human studies. Exclusion criteria: animal trials, in vitro studies and case reports. We also excluded other forms of ‘alternative medicine’ such as reflexology, acupuncture and other homeopathic remedies.

Results:

Lack of common outcome measures prevented a formal meta-analysis. Three studies on the effects of spirulina in allergy, rhinitis and immunomodulation were found. One was a double-blind, placebo, randomised, controlled trial (RCT) of patients with allergic rhinitis, demonstrating positive effects in patients fed spirulina for 12 weeks. The other two studies, although non-randomised, also reported a positive role for spirulina in mucosal immunity. Regarding the use of Ginkgo biloba in tinnitus, a Cochrane review published in 2004 showed no evidence for this. The one double-blind, placebo-controlled trial that followed confirmed this finding. Regarding the use of Vertigoheel in vertigo, two double-blind RCTs and a meta-analysis were identified. The first RCT suggested that Vertigoheel was equally effective in reducing the severity, duration and frequency of vertigo compared with betahistine. The second RCT suggested that Vertigoheel was a suitable alternative to G biloba in the treatment of atherosclerosis-related vertigo. A meta-analysis of only four clinical trials confirms that Vertigoheel was equally effective compared with betahistine, G biloba and dimenhydrinate. Regarding multivitamins and sinusitis, two small paediatric pilot studies reported a positive response for chronic sinusitis and otitis media following a course of multivitamins and cod liver oil. Regarding bromelain (pineapple enzyme) and sinusitis, one randomised, multicentre trial including 116 children compared bromelain monotherapy to bromelain with standard therapy and standard therapy alone, for the treatment of acute sinusitis. The bromelain monotherapy group showed a faster recovery compared with the other groups.

Conclusion:

The positive effects of spirulina in allergic rhinitis and of Vertigoheel in vertigo are based on good levels of evidence, but larger trials are required. There is overwhelming evidence that G biloba may play no role in tinnitus. There is limited evidence for the use of multivitamins in sinus symptoms, and larger randomised trials are required.

Awareness of general practitioners towards treatment of laryngopharyngeal reflux: a British survey

OBJECTIVE

Patients with acid reflux can occasionally present with atypical symptoms such as globus pharyngeus, constant throat clearing, chronic cough, hoarseness, catarrh, choking episodes or asthma-like symptoms. The aim of this survey was to determine whether general practitioners are aware of the atypical manifestations of reflux and the differences in treatment between laryngopharyngeal reflux and gastroesophageal reflux.

DESIGN

Questionnaire Survey.

SETTING

Primary Care

RESULTS

One hundred and sixty general practitioners who routinely refer patients to our Department of Otolaryngology were selected and a postal survey was conducted. One hundred and fifty of these responded (94% response rate). The commonest symptoms for which proton pump inhibitors are prescribed are heartburn (65%), followed by a combination of heartburn and other symptoms (15%), chronic cough (4%), choking episodes (4%), asthma-like symptoms (3%), hoarseness (2%), globus (2%), catarrh (1%), dysphagia (1.5%), frequent throat clearing (1.5%), halitosis and/or bitter taste (1%).

CONCLUSIONS

Our results suggest that the majority of the general practitioners surveyed are unaware of the entity laryngopharyngeal reflux or reflux symptom index. More awareness is required in the primary care setting for early recognition of patients with suspected laryngopharyngeal reflux.

Dual-probe 24-hour ambulatory pH monitoring for diagnosis of laryngopharyngeal reflux

BACKGROUND

Patients with gastroesophageal reflux disease may suffer from a variety of symptoms from the upper aerodigestive tract. The objective of this study was to determine the impact of dual-probe 24-hr pH monitoring in the diagnosis of reflux-related otolaryngological disorders.

METHODS

Twenty-two patients with symptoms such as chronic cough, globus pharyngeus, heartburn, dysphonia and burning sensation of the tongue underwent a complete ear, nose and throat examination, 24-hr dual-probe pH monitoring, and oesophago-gastro-duodenoscopy.

RESULTS

pH monitoring revealed gastroesophageal (distal) reflux in all patients and pharyngeal (proximal) reflux in 21 patients. Treatment consisted of a proton pump inhibitor (esomeprazole). Within 4 weeks 68 per cent of patients had no laryngopharyngeal symptoms; within 8 weeks 95 per cent of patients were symptom-free.

CONCLUSIONS

Patients with atypical reflux symptoms such as hoarseness, globus sensation or throat-clearing responded well to anti-reflux treatment.

Pediatric middle ear infections and gastroesophageal reflux

OBJECTIVES

The pathogenesis of middle ear infections in children is multifactorial and includes infection, anatomical factors, impaired immunologic status, allergy, familial predisposition, male sex, method of feeding and environmental factors. Glue ear remains the commonest cause of deafness in childhood. Gastroesophageal reflux (GOR) is a common problem in the newborn and preschool periods. Recent research suggests that it may be related to eustachian tube dysfunction and otitis media.

METHODS

We review the literature and discuss the possible relationship between Gastroesophageal reflux and otitis media in children.

CONCLUSIONS

The current data are not enough to support antireflux treatment in children with refractory middle ear infections. More prospective randomised placebo-controlled studies are needed.

[Diagnosis and management of squamous cell carcinoma of the head and neck region with unknown primary. A survey of 167 patients]

BACKGROUND

Carcinoma of unknown primary is defined as histological diagnosis of metastasis without diagnosis of a primary tumor. The incidence of CUP is stated in the literature between 3 % and 15 % of all patients with an malignant disease. Histological examination of CUP-metastasis of the neck most frequently shows a squamous cell carcinoma. A retrospective study of patient data was undertaken.

PATIENTS AND METHODS

The study included 167 patients admitted and treated for cervical CUP at the department of Oto-Rhino-Laryngology, Klinikum Grosshadern from 1979 to 1998. Cervical swelling was the first noted symptom in all cases. Other symptoms were pain and dysphagia. Of the 167 patients 134 were men and 33 were women. The average age at admission was 55 years. In the studied collective squamous cell carcinoma had the highest incidence (n = 123). During the 10 year follow-up a primary tumor was found in 36 of the 167 initially diagnosed CUP-patients. In over 90 % of these cases the tumor was localized in the head and neck region. The origin of the tumor was most frequently the tonsilla palatina (n = 7). Of the 167 patients included in the study 118 patients (70,7 %) underwent surgery and additional postoperative radiotherapy. Primary radiotherapy was the treatment of choice in 28 patients, 8 patients received combined radio-chemotherapy as primary treatment and 7 patients were treated with chemotherapy alone. No treatment was performed in 6 patients.

RESULTS

By comparing the treatment methods there was a significant difference of patient survival in regard to the treatment. Patients treated according to treatment-plan II, which includes an additional "diagnostic" tonsillectomy, is significantly higher than that of patients simply undergoing neck dissection and postoperative radiotherapy or primary radiotherapy alone. Treatment of choice in patients with cervical CUP should be a surgical procedure including radical neck dissection and diagnostic bilateral tonsillectomy followed by postoperative radiation of the cervical lymph drainage.

DISCUSSION

Bilateral tonsillectomy is especially important and is correlated with a significant improvement of the survival rate in CUP patients. Additional postoperative radiation of the pharynx from the base of the skull to the upper oesophagus should also be considered, in order to treat a possible--small--primary tumor in this region.

[Impact of 24-hour intraesophageal pH monitoring with 2 channels in the diagnosis of reflux-induced otolaryngologic disorders]

BACKGROUND

Patients with gastroesophageal reflux disease (GERD) may suffer from a large variety of symptoms in the upper aerodigestive tract such as globus sensation, chronic cough, hoarseness and many others. Diagnosis and causal therapy may sometimes be difficult with gastroenterologic evaluation sometimes revealing no pathologic result. The objective of this study was to determine the impact of 24-hour intraesophageal pH monitoring with 2 channels (gastric and laryngeal) in the diagnosis of reflux-induced otolaryngologic disorders.

METHODS

This study included 22 patients presenting to the Department of Otolaryngology with symptoms like chronic cough (n = 3), globus sensation and dysphagia (n = 11), heartburn (n = 2), hoarseness and dysphonia (n = 2) or burning sensation of the tongue (n = 1). Three patients had a pathologic formation in the glottic area (leukoplakia, granuloma, polyp). All patients underwent a otolaryngological examination, a gastroenterological investigation and a 24-hour intraesophageal pH monitoring with 2 channels.

RESULTS

All 22 patients showed laryngeal mucosal lesions (posterior laryngitis). The gastroenterological evaluation with esophagogastroduodenoscopy was normal in 4 cases. 13 patients showed a hiatal hernia, 4 patients were suffering from a reflux-esophagitis grade I and 2 patients from grade II. One patient had an erythema and 5 patients showed erosions of the gastric mucosa. Seven patients had more than one of the above mentioned diagnoses. Intraesophageal pH-monitoring with 2 channels over 24 hours revealed a gastroesophageal reflux of all 22 patients and a high reflux to the laryngeal level of 21 patients, probably causing laryngopharyngeal symptoms. Therapy of the patients consisted of medical antireflux treatment with proton pump inhibitor esomeprazol (Nexium, 40 mg, 1-0-0). Within 4 weeks 15 of 22 patients had no more laryngopharyngeal symptoms or at least a significant reduction.

CONCLUSION

Patients with laryngopharyngeal symptoms such as hoarseness, globus sensation or dysphagia can suffer from GERD, even if typical symptoms such as heartburn or retrosternal pain do not exist and gastroesophageal intervention reveals a normal result. The best diagnostic instrument for the diagnosis of reflux-induced otolaryngologic disorders is a 24-hour intraesophageal pH-monitoring with 2 channels (measure-points at the distal esophagus and laryngeal level). Medical antireflux treatment should consist of proton pump inhibitors (e. g. Nexium) in a dose of 40 mg per day over at least 4 weeks.

[Gastroesophageal reflux -- a common illness?]

For a long time heartburn was not considered a symptom for serious illness. By now, however, it is accepted that the incidence of secondary carcinoma of the esophagus caused by chronic GERD has increased dramatically since the nineteen-seventies. Mechanisms leading to GERD are complex and its incidence is not necessarily pathological. However pathological reflux in the lower esophagus (pH lower than 4 in 6 % of 24 hours), caused by decreased sphinctertonus, impaired peristalsis and clearance of the esophagus, may lead to complications. Helicobacter pylori may play a key role in GERD. There is strong evidence for a protective effect of Hp-infection in the development of GERD. In pangastritis, caused by Hp-infection, gastric acid production is inhibited resulting in a reduction of stomach-acid-concentration. This may be caused by either the chronic infection itself and the resulting atrophy of the stomach-mucosa, by the ammonia-producing HP-bacteria, or an increase in acid re-absorbtion of gastric epithelium. Laryngopharyngeal reflux (LPR) often results in atypical manifestations with oral, pharyngeal, laryngeal, and pulmonary disorders. Laryngopharyngeal reflux is known to contribute to posterior acid laryngitis and laryngeal contact ulceration or granuloma formation, laryngeal cancer, chronic hoarseness, pharyngitis, asthma, pneumonia, nocturnal choking, and dental diseases. Today, PPI are the medication of choice in both acute and long-term (prophylactic) therapy of GERD. The so called "step-up-strategy" of medication is no longer recommended. Here, patients were first treated with antacids, then prokinetics followed by H2-blockers and finally low-dose PPI. Only in the case of persisting symptoms medication was further increased to high-dose PPI therapy. In the past this increase in medication lead to a prolonged healing process and consequently to higher medication costs. Studies have shown that a "step-down"-therapy, beginning with high dose PPI, is highly preferable, since it is much more effective. Depending on the degree of the symptoms, however, medication may also be applied "on-demand". The BfArM has approved this kind of medication application only for Esomeprazol (Nexium mups 20 mg).

[Chromosome 5q-syndrome-ENT pathologies]

INTRODUCTION

The interstitial deletion of chromosome 5q is a disease of rare incidence, which might be hereditary or caused by spontaneous changes within the chromosome respectively. The pathology is based on the loss of chromosomal material within the long arm of chromosome 5. Clinical manifestations are mainly known in hematology, particular such as malignancies or hematopoetic malformation. Other morphological characteristics that have been described following deletion of chromosome 5q are deformity of the skull and the joints as well as heart defects. In the following we will present some pathologic findings focussing on the head and neck.

PATIENT

We introduce a young female patient of 8 months with deletion of the long arm of chromosome 5q. In addition to the known skeletal and hematopoetic disorders we discovered a unilateral deafness and a contralateral middle-graded combined hearing-loss as well as laryngomalacia.

CONCLUSION

Infants with chromosome 5 syndrome should undergo an otorhinolaryngological examination to investigate anatomic malformations. In particular a brainstem electric response audiometry should be considered for early diagnosis and treatment of a possible hearing-loss. This ensures adequate and early support of the patients physical and psychological development.

[Respiratory manifestations of reflux disease. Gastric acidity--poison for larynx, teeth and respiratory tract]

Gastroesophageal reflux is now a generally accepted risk factor for the development of adenocarcinoma of the esophagus. Less well known is the relationship of reflux disease (GERD) and respiratory disorders. Among the extra-esophageal manifestations of reflux disease is reflux laryngitis, which affects up to 78 patients with chronic hoarseness, Reinke's edema, laryngeal stricture, postnasal drip, asthma and non-cardiac chest pain. Despite popular opinion, changes in lifestyle (for example, cessation of smoking and drinking, avoidance of fatty foods) do not result in an improvement in symptoms. The treatment of choice for GERD is the use of proton pump inhibitors (PPI) in the form of stepdown therapy; in individual cases as symptom-orientated on-demand therapy.

[Follow-up assessment of intratympanic gentamicin therapy and Saccotomia in Menière's Disease]

BACKGROUND

The intratympanic application of ototoxic antibiotics and saccotomia have been well documented in severe cases of one-sided Menière's disease for 30 years now. Both treatment methods are still subject to controversial discussion.

PATIENTS AND MATERIAL

This study includes 8 patients suffering from persistent one-sided Menière's disease after treatment with gentamicin application and additional saccotomia (n=2). We performed follow-up visits including the assessment of hearing ability, vestibular function and cranial MRI, 2-10 years after onset of treatment.

RESULTS

After therapeutic interventions 7 patients reported to be healed of their symptom vertigo. In 4 patients the gentamicin-treated vestibular organ did not respond to thermic stimulus at the time of follow-up examination. Auditory threshold shift was observed in 3 patients (1 permanent, 2 temporary), whereas hearing threshold improved in 2 patients. Tinnitus was attenuated in 3 patients, while 1 patient suffered from posttherapeutic onset of tinnitus. Morphological and structural changes due to Menière's disease and treatment procedures were ruled out by cranial MRI.

CONCLUSION

The intratympanic application of ototoxic medication is a safe and effective treatment method in severe cases of Menière's disease. Saccotomia should be considered as therapeutic regimen for persistent symptoms after repeated application of gentamicin.

[Expression of retinoic acid receptors in head and neck squamous cell carcinomas and their possible implication for chemoprevention]

BACKGROUND

Retinoic acid and its natural and synthetic analogs (retinoids) affect a wide array of biological processes. Retinoids are used in the treatment of many skin diseases and are promising drugs for several cancers. Most of their actions are thought to result from changes in gene expression which is done through nuclear retinoic acid receptors and retinoid X receptors. We conducted a study to determine whether the expression of these receptors is different in malignant tumors and tumor cell lines versus normal tissue.

METHODS

We performed reverse transcription PCR from 29 tissue specimens of squamous cell carcinomas and one melanoma and of the head and neck as well as from 13 cell lines established from head and neck cancer. We were looking for the expression pattern of RARalpha, beta, gamma and RXRalpha.

RESULTS

Only RARgamma was expressed 100 % in cell lines and tissue specimens. RARbeta showed a 100 % expression only in tissue specimens whereas a 54 % expression in cell lines was seen. All other receptors were diminished in their expression. In the positive controls all receptors were expressed 100 %.

CONCLUSION

The expression of RARalpha and RARbeta was partially lost in cell lines established from squamous cell carcinoma of the head and neck. The 100 % expression of RARbeta in tissue samples versus 54 % in cell lines can be explained by clonal growth of malignant cells in cell lines and also possible "contamination" by normal cells in the tissue specimen. In concordance with the literature it seems that RARalpha and beta play a pivotal role in mediating the response to retinoids.

[Manifestations of gastroesophageal reflux in the otorhinolaryngology tract]

BACKGROUND

Gastroesophageal reflux disease (GERD) is associated with a wide spectrum of otolaryngologic disorders and extraesophageal complications of the upper aerodigestive tract. Previous studies of patients diagnosed with GERD have reported symptoms such as asthma, chronic cough, pneumonia, laryngitis, but also other oral, rhinopharyngeal and laryngeal disorders, e.g. sore throat, globus sensation, and hoarseness. The objective of this study was to determine the incidence of gastroenterologic diseases in patients complaining of upper aerodigestive, pulmonary, laryngeal, pharyngeal, oral, and cervical disorders that are possibly attributable to GERD.

PATIENTS

This study included 40 patients, who presented to the department of Otolaryngology with chronic complaints of at least one of the following symptoms or disorders during a minimum period of 3 months: dysphagia (n = 28), sensation of globus pharyngeus (n = 28), hoarseness (n = 20), odynophagia (n = 22), heartburn (n = 16), postnasal drip (n = 15), sore throat (n = 22), cough (n = 14), throat clearing (n = 11), laryngospasm (n = 6), and voice fatigue (n = 6). A complete examination of the head and neck was performed. Inflammatory disorders of the nose and the paranasal sinuses could not be confirmed by history, nasal endoscopy and Water's view x-ray or CT-scan of the paranasal sinuses in all patients.

RESULTS

The main otorhinolaryngologic findings were laryngeal lesions (n = 38), including posterior laryngitis, erythema and edema of the interarytenoideal region, and chronic hyperplastic laryngitis. All patients were referred for gastroenterologic evaluation, where esophagogastroduodenoscopy was performed with histological examination of biopsy specimens. Different gastroenterologic diseases such as GERD, gastritis and hiatal hernia were confirmed in 30 of 40 cases, and appeared solely or in combination with each other. GERD was the most frequent gastroenterologic disease (48%), followed by hiatal hernia (45%) and Helicobacter pylori positive antrum gastritis (23%). Patients with GERD were treated with medical antireflux therapy, e.g. 20 mg to 40 mg of the proton pump inhibitor omeprazole daily. There was a remarkably good therapeutic outcome, since laryngeal disorders and findings as the result of gastroenterologic diseases resolved in 29 out of 30 patients. To date, these therapeutic results were maintained for the mean follow-up period of 8 months.

CONCLUSIONS

It is concluded that in many patients, suffering from the above-mentioned otolaryngologic symptoms, occult gastroesophageal diseases are present. However, laryngoscopic findings are subtle and meticulous examination is mandatory. Medical antireflux treatment is effective for relief of symptoms and mucosal healing. Thus, extraesophageal otolaryngologic symptoms and laryngeal manifestations are to be considered as extragastrointestinal manifestations mainly of reflux disease.

Incidence of tracheo-oesophageal fistulas after primary voice rehabilitation with the Provox or the Eska-Herrmann voice prosthesis

Salivary leakage can be a major symptom of valve failure or incorrect positioning of indwelling voice rehabilitation valves in a tracheo-oesophageal fistula. Usually, removal of the valve for a short time leads to shrinking of the fistula or a simple valve replacement procedure resolves the problem. If the fistula, however, does not close spontaneously, symptoms persist and the fistula may have to be closed surgically. In a retrospective study, data of 103 patients who underwent laryngectomy and primary voice rehabilitation between 1989 and 1998 with either the Provox or the Eska-Herrmann prosthesis were compared with regard to surgical fistula closure requirement. A total of 55 patients underwent laryngectomy and primary voice rehabilitation with the Eska-Herrmann and 48 with the Provox prosthesis. Initial tumour treatment also included post-operative radiotherapy for all patients in the study. In total, surgical fistula closure had to be performed in three patients, all of whom had been treated with the Provox prosthesis. The time span between initial voice rehabilitation and surgical closure of the fistula was 5 months, 21 months and 24 months in all three patients respectively. None of the fistulas developed in relation to recurring tumour disease. The Provox prosthesis seem to have a higher risk of developing fistulas necessitating surgical intervention, even years after initial tumour therapy, than the Eska-Herrman prosthesis. These complications may be due to the larger tracheo-oesophageal fistula necessary to fit the larger diameter of the Provox prosthesis.

Initial experience in the treatment of oral leukoplakia with high-dose vitamin A and follow-up 5-aminolevulinic acid induced protoporphyrin IX fluorescence

The aim of photodynamic diagnostics is complete visualization of all neoplastic lesions in a tumorous organ after the application of a tumor-selective photosensitizer. We explored the potential benefit of a combination of retinyl palmitate for the treatment of oral leukoplakias and follow-up diagnosis of malignant tissue by using 5-aminolevulinic acid (5-ALA) as a fluorescence marker. Semiquantitative measurements were performed following the topical application of 5-ALA in six patients. After biopsy and histological evaluation of tissue specimens the patients were treated with escalating doses of retinyl palmitate. After treatment periods ranging from 4 to 8 weeks 5-ALA was again applied for photodetection of persisting fluorescence. In all cases prior to retinyl palmitate treatment a prominent red fluorescence indicated tissue dysplasia. Eight weeks after treatment with retinyl palmitate decreased red fluorescence intensities were found, and repeated histological evaluations showed no persistent signs of dysplastic lesions. Our initial experience shows that high doses of retinyl palmitate can be useful for treating dysplastic lesions in the upper aerodigestive tract and can be monitored with 5-ALA induced protoporphyrin IX fluorescence.

[The interesting case No. 39. Differential diagnosis of acute antibiotic-resistant pharyngitis]

We report on a 41-year old female patient presenting a history of long-term sore throat, in addition to ulcers on both tonsils, the base of the tongue, the hypopharyngeal mucosa, and a laryngeal edema. She underwent diagnostic tonsillectomy and microlaryngoscopy on the suspicion of malignancy. Clinical and histopathological investigations demonstrated granulomatous inflammation with necrosis containing acid-fast rods in the tissue specimens. Furthermore, the presence of acid-fast bacilli in the bronchial lavage suggested the diagnosis of a possibly reactivated pulmonary tuberculosis. The present case provides evidence that pharyngeal tuberculosis may represent the first manifestation of tuberculosis. Therefore, the differential diagnosis of nonspecific symptoms such as sore throat should include tuberculosis as a causative factor.

Anti-labyrinthine antibodies in a patient with relapsing polychondritis

Relapsing polychondritis is a rare inflammatory disease that causes destruction of cartilaginous tissue in various anatomical regions. We report here about a 55-year-old female patient with relapsing polychondritis that involved the right auricle, both audiovestibular organs and both eyes. The patient presented with persisting inflammation of the right auricle, sudden lower-frequency hearing loss, acute moderate vertigo with nausea and mild ocular symptoms. Immunofluorescence assays were used for the detection of antibodies against the cochlea and the vestibular organ and demonstrated the presence of circulating antibodies against the audiovestibular organ. No staining for anti-corneal IgG was detected. Improvement of clinical disease was achieved by treatment with systemic steroids and vasodilator drugs, and long-term medication with low-dose corticosteroids.

[Rhinoscleroma: a case report]

BACKGROUND

Rhinoscleroma is a rare infectious disease of the upper respiratory tract caused by Klebsiella rhinoscleromatis. The nasal mucosa represents the primary region of occurrence which is most likely a result of respiratory transmission. Without adequate++ treatment, the disease can potentially spread to the rest of the upper and middle respiratory tract within a period of several years. Healing often occurs with extensive scarring and adhesions of the nose, palate and larynx. A life threatening late stage manifestation includes subglottic stenosis requiring immediate surgical intervention. Medical treatment primarily consists of a long-term course of antibiotics. Ciprofloxacin (Fluoroquinolon) has proved to be one of the most effective drugs.

CASE REPORT

We report about a 33 year-old Egyptian male, who presented in our department with a 10 year history of a previously, only temporarily successfully treated rhinoscleroma. His main symptoms were nasal obstruction, epistaxis and inspiratory stridor.

FINDINGS

We began treatment with Ciprofloxacin over a four week period, which lead to an improvement of his symptoms. The treatment was considered complete after several biopsies and smears were negative for live specimens. We then chose to reduce the scar tissue that was causing obstruction in the larynx and the nose.

CONCLUSION

The rhinoscleroma is a rare disease in geographic areas with poor hygiene and can mimic several other infectious and malignant diseases. Treatment should include a long-term antimicrobial therapy and surgical intervention in cases with symptomatic obstruction.

[Intra-parotid neurofibroma of the facial nerve]

BACKGROUND

Solitary intraparotid facial neurofibromas are extremely rare. These tumours arise from Schwann cells, in most cases as a manifestation of neurofibromatosis. In an intraparotid localisation, they can mimic other parotideal tumours. Due to their slow growth, they may be clinically inapparent for a long time.

CASE REPORT

We present the case of a patient with a right intraparotid neurofibroma originating from the facial nerve. He noted a slight facial weakness for the last three years and dullness over the preauricular area. On operation, all facial nerve branches were incorporated in the tumour mass. A total resection via monitoring technique of facial nerve function was performed. Postoperatively, the patient suffered from an incomplete facial palsy.

CONCLUSION

This case highlights particularly the importance of a concise diagnostic work-up of every facial palsy. Precise histological diagnosis is particularly essential because of the different biological behaviour of neurofibromas in contrast to neurinomas. With preoperative facial palsy the chance of facial nerve preservation decreases. Clinical and operative experience with parotid gland neurofibromas shows that recovery of facial nerve defects is mostly incomplete.

[Unusual metastasis of renal cell carcinoma. A case report with review of the literature]

BACKGROUND

The occurrence of metastasis of renal cell carcinomas in the head and neck region is extremely rare. Metastasis in the larynx, hypopharynx, and the nasal sinuses has been reported. We report here about a 55-year-old female with metastasis in the soft palate and tonsil, which occurred 10 years following tumor nephrectomy.

RESULTS AND CONCLUSIONS

The incidence of metastasis in renal cell carcinomas can be observed even many years following initial curative treatment of the primary tumor. Although rare in the region of the head and neck, they can often be mistaken for benign tumors such as hemangiomas or inflammatory tissue. The treatment of choice is radical surgical resection.

[Basal cell adenoma of Weber's glands]

INTRODUCTION

In 1967, Kleinsasser first reported about basal cell adenomas in salivary glands, which represent approximately 1-2% of all salivary gland tumors. About 70% of these tumors are found in the parotid gland. Less often the minor salivary glands are involved, particularly in the upper lip region. We would like to report on a case of occurrence in the upper pole of the palatine tonsil.

CASE REPORT

A 68-year-old woman was seen, who complained about a growth in her left tonsil. Other than a slow increase size, she had no symptoms. Examination revealed a solid tumor approximately 3 cm in diameter which displaced the upper part of the tonsil medially. In an MRI study, the neoplasia demonstrated a low signal intensity in the T1-weighted images and a high signal intensity in the T2-weighted images, which is relatively typical for a cystic structure. The tumor extended to the base of skull, and was completely resected by extended tonsillectomy. Histologic studies showed a cystic, regressive basal cell adenoma.

DISCUSSION

When compared to pleomorphic adenomas, basal cell adenomas are relatively rare in the region of the soft palate. This case is especially interesting because we assume the origin of the tumor to be in the supratonsillar salivary glands (Weber's glands) and also because of the unusually pronounced cystic regressive changes.

[Detection of an "autocrine loop" between EGF receptor and TGF-alpha in head-neck carcinomas]

BACKGROUND

In order to find a prognostic marker for the course of disease in head and neck cancer, we hypothesized that patients with rapid disease progress would produce increased levels of transforming growth factor alpha (TGF-alpha) and its cell surface receptor, the epidermal growth factor receptor (EGFR).

METHODS

Using molecular biological techniques, we examined the incidence of TGF-alpha and EGFR expression in 43 patients with tumors of the head and neck. The expression data were correlated with the course of disease in four-year follow-up. The tumors were classified into four groups according to the EGFR status: Group 1, no expression for EGFR (15 samples); group 2, expression level 10 for EGFR (18 samples); group 3, expression level 50 for EGFR (7 samples); and group 4, expression level 100 for EGFR (3 samples).

RESULTS

An expression for the TGF-alpha protein was only detected in group 4. There was a significant correlation with EGFR overexpression in group 4 and survival compared with group 3 (p < 0.01) and group 1 (p < 0.05). The mean survival for group 1 to 4 was 27, 33, 34, and 10 months, respectively.

CONCLUSION

The analysis of all patients revealed that the patients with synchronous expression of EGFR and TGF-alpha had the poorest prognosis. Increased production of TGF-alpha and EGFR in tumors of the head and neck may serve both as a marker for tumor progression and as a target for preventive therapies.

Positive impact of retinyl palmitate in leukoplakia of the larynx

Laryngeal leukoplakia can be a premalignant precursor of squamous cell carcinoma, is often tobacco-related and can usually be readily monitored by indirect laryngoscopy. One of the main motivations for using retinyl palmitate in patients with persistent leukoplakia was to avoid general anesthesia for elderly patients, who are considered to be high-risk patients when direct larynoscopy is required for possible tissue biopsy. Our study was the first to investigate the effectiveness and toxicity of high-dose retinyl palmitate in the treatment of laryngeal leukoplakia. Treatment was divided into two phases. In the first phase, all patients underwent induction therapy with 300,000 IU/day of retinyl palmitate for the 1st week, which was then adjusted up to 1,500,000 IU/day in the 5th week in patients with resistant lesions. Patients whose lesions progressed during this period were withdrawn from the study. In the second phase, patients whose lesions responded to treatment or remained stable were assigned to a maintenance therapy of 150,000 IU/day. Complete remission was observed in 15 of 20 patients (75% of cases). Partial response was seen in the remaining 5 patients, with 3 of the patients relapsing. The median duration of treatment and follow-up was 18 months (range, 12-24 months). These results indicate that retinyl palmitate has substantial activity in laryngeal leukoplakias. Since only minor side effects were seen, the medication is an excellent candidate as a preventive agent for laryngeal cancer.

Long-term follow-up of larynx leukoplakia under treatment with retinyl palmitate

BACKGROUND

Larynx leukoplakia can be a premalignant precursor of squamous cell carcinoma, is often tobacco related, and can be monitored easily by indirect laryngoscopy. One of the main motivations for using retinyl palmitate in patients with larynx leukoplakia was to avoid general anesthesia for the elderly patients, who are considered to be at high risk for undergoing direct laryngoscopy. Our study investigates for the first time the effectiveness and toxicity of high-dose retinyl palmitate in the treatment of larynx leukoplakia.

METHODS

Treatment was divided into two phases. In the first phase, all patients underwent induction therapy with a high-dose of retinyl palmitate (A-Mulsin Hochkonzentrat, Mucos Pharma, Geretsried, Germany) with 300,000 IU/day for the first week and up to 1,500,000 IU/day, in patients with resistant lesions, in the fifth week. Patients whose lesions progressed during this period were withdrawn from the study. In the second phase, patients whose lesions responded to treatment or remained stable were then assigned to a maintenance therapy of 150,000 IU/day.

RESULTS

We observed a complete remission rate of 75% (15 of 20 patients). Among the 5 patients with partial response, 3 relapsed. The median duration of treatment and follow up was 18 months (range 12-24 months).

CONCLUSIONS

These results indicate that retinyl palmitate has substantial activity in larynx leukoplakias. Furthermore, only minor side effects make it an excellent candidate as a preventive agent for larynx cancer.

Evaluation of pedicled skin flap viability by pH, temperature and fluorescein: an experimental study

In order to test methods of predicting skin flap viability, a skin flap model in Sprague-Dawley rats was established. As criteria for studying skin flap survival, we compared measurement of skin pH, temperature, as well as fluorescence photography and computer aided digital morphometry (CADM). Ninety male Sprague-Dawley rats were divided into three groups in which pedicles were clamped for 10, 15, or 20 h. A standardized bipedicled skin flap was prepared, maintained by the epigastric artery, vein and nerve. All flaps were sutured back in place immediately after clamping. We found that postoperative prediction of flap survival based solely upon external appearance was impossible until the 2nd postoperative day. Changes in pH were not statistically significant in the prediction of vital or necrotic flaps. The temperature measurements showed, that in the event of viability the decrease in flap temperature versus the reference temperature (rectal temperature) was significant (P < 0.0094 in Group II, 15 h of ischaemia) or at least a tendency to significance (P < 0.059 in Group III, 10 h of ischaemia) bigger than in the event of partial or total flap necrosis. The photographic documentation using fluorescein showed that all coloured areas survived. Group I (20 h) showed predominantly total flap necrosis. Most flaps in Group III (10 h) exhibited a small necrotic area at the tip. In Group II (15 h) no typical staining pattern could be observed. Furthermore, computer aided digital morphometry demonstrated a decrease of the necrotic area by 7% between the 2nd and 4th postoperative day in Groups II and III. The method which gave the most exact prediction about viability was the fluorescein staining of the flaps via the tail vein.

Expression of retinoic acid receptors in squamous cell carcinomas and their possible implication for chemoprevention

Retinoic acid and its natural and synthetic analogs (retinoids) affect a wide array of biological processes. Retinoids are used in the treatment of many skin diseases and are promising drugs for several cancers. Most of their actions are thought to result from changes in gene expression which is caused via nuclear retinoic acid receptors and retinoid X receptors. We conducted a study to determine whether the expression of these receptors is different in malignant tumors and tumor cell lines versus normal tissue. We performed reverse transcription PCR from 29 tissue specimens of squamous cell carcinomas and one melanoma of the head and neck, as well as from 13 cell lines established from head and neck cancer. We were looking for the expression pattern of RAR alpha, beta, gamma and RXR alpha. Only RAR gamma was expressed 100% in cell lines and tissue specimens. RAR beta showed 100% expression in tissue specimens whereas 54% expression in cell lines was seen. All other receptors were diminished in their expression. In the positive controls all receptors were expressed at 100%. The expression of RAR alpha and RAR beta was partially lost in cell lines established from squamous cell carcinoma of the head and neck. The 100% expression of RAR beta in tissue samples versus 54% in cell lines can be explained by the clonal growth of malignant cells in cell lines and also possible "contamination" by normal cells in the tissue specimen. In concordance with the literature it seems that RARa and beta play a pivotal role in mediating the response to retinoids.

Coexpression of epidermal growth factor receptor and TGF-alpha and survival in upper aerodigestive tract cancer

In order to find a prognostic marker for the course of disease in head and neck cancer we hypothesized that patients with rapid disease progress would produce increased levels of transforming growth factor alpha (TGF-alpha) and its cell surface receptor, epidermal growth factor receptor (EGFR). Using molecular biological techniques, we examined the incidence of TGF-alpha and EGFR overexpression in 43 patients with tumors of the head and neck. The expression data was correlated with the course of disease in a 4 year follow-up. The tumors were classified into four groups according to the EGFR status: Group 1, no expression for EGFR (15 samples); group 2, expression level 10 for EGFR (18 samples); group 3, expression level 50 for EGFR (7 samples) and group 4, expression level 100 for EGFR (3 samples). Expression for the TGF-alpha protein was only detected in group 4. There was a significant correlation with EGFR/TGF-alpha overexpression in group 4 and survival compared when with group 3 (p < 0.01) and group 1 (p < 0.05). The mean survival for group 1 to 4 was 27, 23, 34 and 10 months, respectively. The analysis of all patients revealed that the patients who expressed EGFR as well as TGF-alpha had the poorest prognosis. Increased production of TGF-alpha and EGFR in tumors of the head and neck may serve both as a marker for tumor progression and as a target for therapy (e.g. inhibition of the autocrine loop, blockage of TGF-alpha binding).

[High concentrate A-mulsin, a new therapy concept in laryngeal leukoplakia]

BACKGROUND

Leukoplakia, a white patch in the oral cavity or in the larynx that cannot be scraped off is a premalignant precursor of squamous cell carcinoma. It is tobacco-related and easily monitored. The rate of transformation of leukoplakia into invasive cancer is directly related to the degree of histologic abnormality. In the largest and longest study in the United States (mean follow-up, 7.2 years), the long-term transformation rate for dysplastic lesions was 36%. Surgical removal is considered the best therapy. However many patients operated on for oral leukoplakia later develop local relapses, new leukoplakias, or squamous cell carcinoma. Although leukoplakia lesions can show spontaneous regression, the response rate observed under treatment of retinoids is much greater.

METHODS

In our study, high-dose retinyl palmitate was used for the first time on leukoplakias of the larynx. The study was conducted in two phases. In the first phase, all patients underwent induction therapy with a high dose of Retinyl Palmitate (A-Mulsin Hochkonzentrat, Mucos Pharma, Geretsried, Germany) 300.000 IU daily for the first week up to 1,500,000 IU daily in the fifth week. Patients whose lesions progressed during this period were withdrawn from the study. In the second phase, patients whose lesions responded to treatment or remained stable were then assigned to a maintenance therapy. The median duration of treatment was 104 days (range 15-272).

RESULTS

We observed a complete remission rate of 65% (20 out of 31 patients), a partial remission in 8 patients (26%) and a relaps in three patients (9%) during the next 15 months follow-up. Relapses were mainly seen in patients with a history of a carcinoma in situ or squamous cell carcinoma.

CONCLUSIONS

One of the main reasons for using retinyl palmitate in patients with larynx leukoplakia was to avoid general anesthesia in elderly patients who were considered as high risk patients for undergoing surgery. These results indicate that retinyl palmitate has substantial activity in larynx premalignancy. Because of its minor toxicity, it is an excellent candidate for a preventive agent for larynx cancer.

Immune defects in patients with head and neck cancer

Any deficiency or suppression of the immune response in head and neck cancer patients might be due to genetic factors of the host (patient factors), to tumor antigens (tumor factors) or to the medical treatment such as irradiation, anesthesia, major surgery or cytokine therapy (treatment factors). In order to achieve an effective adjuvant immunotherapy a thorough analysis of the immune situation is a prerequisite. With the increasing knowledge of the fine interactions with the immune system, the armamentarium has increased over the years. At the beginning only skin testing and T- and B-cell numbers were analyzed, whereas today a correlation of cell numbers, distribution and function is feasible.

Oncogenes related to head and neck cancer

Cancer has been defined as a fundamental disorder of cellular growth control. Which arises in some cells through changes in genes (DNA-level: geneamplification, mutation and rearrangement) or their expression (RNA- and protein-level), and gives these cells a growth advantage in comparison to the surrounding cells. Since the last decade we know the identity of these genes and the nature of the changes they underwent in the cancer cell. Only a few of the known oncogenes play a role in head and neck cancer. These are the EGFR (epidermal growth factor receptor), c-myc, the ras gene family, int-2, hst- 1 and bcl- 1. In some clinical disorders, like childhood neuroblastoma and breast cancer, oncogenes play already an important role in tumor staging as well as a prognostic parameter. The aim for the future is the therapeutic application of oncogenes better known as gene therapy.

erbB-3, a third member of the erbB/epidermal growth factor receptor gene family: its expression in head and neck cancer cell lines

Proto-oncogenes encoding growth factor receptors constitute several distinct families with close overall structural homology. The highest degree of homology can be observed in their catalytic domains, which are essential for intrinsic tyrosine kinase activity. Growth factor receptors in several of these families play critical roles in the regulation of normal cell growth and development. Some of these molecules have been implicated in the neoplastic process as well. A related DNA fragment distinct from epidermal growth factor receptor and erbB-2 genes was detected by reduced stringency hybridization of v-erbB to normal genomic human DNA. The expression of erbB-3 was studied by southern and northern blot technique in a subset of nine head and neck tumor cell lines, as well as in three immortalized cultures established from normal human salivary glands. No gene amplification of erb-B-3 was noted in any of the head and neck cell lines. The 6.2 kb transcript of erbB-3 was elevated significantly in an epidermoid carcinoma of the larynx (A388) and an esophageal carcinoma (HA 114).

An association of the RB gene with osteosarcoma: molecular genetic evaluation of a case of hereditary retinoblastoma

A 24-year-old male patient with hereditary retinoblastoma and a poorly differentiated osteoblastic osteogenic sarcoma was found to carry a mutant RB1 allele in all cells. This findings was most likely a point mutation or microdeletion because Southern blot analysis of peripheral blood DNA failed to disclose any structural aberration of the RB1 gene. A somatic mutation (deletion) affecting the other allele was found in the osteosarcoma cells. Management of tumor by external radiotherapy in early age is questioned because the effect of irradiation is to significantly increase the total incidence of second tumors above the already high incidence in non-irradiated patients.

erbB-2/Her-2 gene amplification and overexpression in parotid gland tumors

Proto-oncogenes represent a family of normal cellular genes that were identified on the basis of their similarity to genetic sequences with known tumorigenic or transforming potential. Accumulating evidence links alterations in either the structure, copy number, or expression of one or another of these genes to neoplasia. One such gene, called erbB-2/Her-2 was found amplified in an adenocarcinoma of the human salivary gland and has also been found associated with primary human breast cancer. Patients with multiple copies of the gene have had a shorter overall survival. In the present study, 21 tumors of the parotid gland were examined by Southern and Northern blot hybridization for amplification and possible overexpression of the erbB-2/Her-2 oncogene. Normal parotid gland tissue was used as negative control. The parotid gland lesions comprised 7 pleomorphic adenomas, 5 squamous cell carcinomas, 4 cases of chronic fibrotic sialadenosis, 3 mucoepidermoid carcinomas as well as 1 lymphoma and 1 cystadenolymphoma. Gene amplification was found in 1 of the pleomorphic adenomas, with 2 tumors showing a significant overexpression of the erbB-2/Her-2 oncogene. Because 3-5% of all pleomorphic adenomas undergo malignant transformation, close follow-up of patients is currently underway.

Assessment of tumorous mandibular involvement by transcutaneous ultrasound and flexible endosonography

Tumorous involvement of the mandible affects the prognosis and choice of treatment. To evaluate the usefulness of transcutaneous ultrasound and recently-developed flexible endosonography and their ability to display bone invasion in the lower jaw, we studied 33 non-selected patients with extensive, histologically-verified oral and oropharyngeal carcinomas. Both sonographic examinations were performed prospectively in all patients prior to surgery, without knowledge to the sonographer of the results of other imaging methods. Histological findings served as gold standards and offered 14 mandibular involvements. Flexible endosonography is characterized by high accuracy data in assessment of mandibular involvement occurring in tumors of the floor of the mouth and of the tonsil. On the other hand acceptable results by transcutaneous ultrasound could only be obtained in assessing bone invasion of oral tumors. However, osseous destruction in patients with oropharyngeal tumors were not detectable as the involved medial surface of the mandibular ramus was inaccessible to the extraorally placed transducer. Both sonographic methods, especially endosonography, enabled the examiner to differentiate cortical bone as opposed to spongiosa involvement in many cases, but failed in assessment of tumorous periosteal involvement. Pitfalls in detection and differentiation of bone invasion with false positive and false negative findings are discussed with regard to mandibular anatomy, for both intra- and extraoral examination.

[Oncogenes and their significance for head and neck cancers]

During the past few decades medical science has accepted the concept that cancer is a fundamental disorder of cellular growth control. A disorder can originate in some cells through changes in genes (DNA level: gene amplification, mutation and rearrangement) or their expression (RNA and protein levels), and stimulates growth in contrast to surrounding cells. Over the last decade genes affected in the cancer cell have been identified as well as the nature of changes undergone. Only a few of the known oncogenes play a role in head and neck cancer. These are epidermal growth factor receptor, c-myc, the ras gene family, int-2, hst-1 and bcl-1. In some clinical disorders, such as childhood neuroblastoma and breast cancer, oncogenes have been shown to play an important role in tumor staging or as a prognostic parameter. The aim for future therapy is the effective application of oncogenes (or "gene therapy") in clinical practice.

[Overexpression of protein kinase-C-isoenzymes in human tumor cell lines]

A major biochemical pathway that has been implicated in the control of normal and malignant growth involves phosphoinositide metabolism. In this pathway, receptor-mediated activation of a phosphoinositide-specific phospholipase C causes the hydrolysis of phosphatidylinositol-4,5-bisphosphate which generates two putative second messengers, inositol-1,4,5-trisphosphate and diacylglycerol (DAG). Since DAG has been shown to be elevated in many transformed cells, we sought to determine if the levels of PKC isoenzymes are also increased. Northern blot analysis of mRNAs from 46 human tumour cell lines was performed using probes for the human PKC-I (gamma), PKC-II (beta) and PKC-III (alpha) genes. PKC-II mRNAs were significantly increased in 4 out of 12 sarcoma lines and 1 malignant melanoma cell line. PKC-III was increased in 2 out of 12 sarcoma cell lines and 1 kidney carcinoma cell line. In contrast, in the majority of carcinoma-derived cell lines tested, there was a decreased or moderate expression of either PKC-II or PKC-III mRNAs or both. It is interesting that tumour cell lines which overexpressed one isoenzyme (e.g. PKC-II), did not contain detectable levels of another isoenzyme (e.g. PKC-III), as determined by Northern blotting. Altogether, these results suggest that the overexpression of distinct PKC isoenzymes may be involved in abnormal growth regulation in some human tumours, especially in sarcomas.