Mirko Tos

The natural history of vestibular schwannoma.

Objective: The incidence of vestibular schwannomas (VSs) approaches 20 per million/yr. As treatment may depend on tumor growth, there is a demand of a treatment strategy based on hard data on the growth pattern of these tumors. This article reports growth data registered prospectively in 552 patients. Study Design: Of the 1,818 consecutive patients, diagnosed with VS during the period from 1975 to 2005, 729 patients were allocated to observation by repetitive magnetic resonance imaging. At least two scans had been performed in 552 patients at the time of data analysis. Two hundred thirty patients had a tumor confined to the internal acoustic meatus, whereas 322 patients had a tumor with an extrameatal extension. Growth to extrameatal extension was the definition for growth in intrameatal tumors, whereas a largest diameter change of more than 2 mm was the criteria for growth/shrinkage of extrameatal tumors. The mean observation time was 3.6 years (range, 1-15 yr). Results: Seventeen percent of the intrameatal tumors grew, whereas significantly more of the extrameatal tumors displayed growth during the period (28.9%). Growth occurred within the first 5 years after diagnosis. No correlation could be demonstrated between tumor growth rate, sex, or age. Conclusion: VS growth occurs within the first 5 years after diagnosis in a limited number of tumors, primarily in tumors with an extrameatal extension. We found no relation between tumor growth and sex or age. These findings justify primary observation of small tumors. A treatment strategy is proposed for this disease, focusing on the patient group allocated to observation.

New and modified reporting systems from the consensus meeting on systems for reporting results in vestibular schwannoma.

Standardization of reporting results of vestibular schwannoma (acoustic neuroma) surgery has been discussed ever since the first Acoustic Neuroma Conference in 1991 (Copenhagen). However, it has been difficult to reach consensus and to agree on a standardized system because these conferences are held only once every 4 years. In view of this, the Consensus Meeting on Systems for Reporting Results in Acoustic Neuroma (chairman, Dr. Kanzaki) was convened, and 40 neurotologists, neurosurgeons, and neuroradiologists attended on November 7 to 9, 2001, in Tokyo as the 11th Keio University International Symposium for Life Sciences and Medicine. The objectives set for the meeting were as follows: 1. A uniform classification for reporting results should be promoted. 2. The classification should be used by all professionals (general physicians, audiologists, otolaryngologists, neurologists, neurosurgeons, and neuroradiologis ts) involved in the diagnosis and management of vestibular schwannoma. 3. The classification should be easy to learn and practicable for all professionals. 4. The classification should be easily understood by patients. 5. Standard guidelines should be provided that would facilitate interinstitutional comparison of results of surgical studies (1). 6. A new and modified rational version of existing classifications should be provided. The following consensus on reporting systems was achieved:

Acoustic Neuroma (Vestibular Schwannoma): Growth and Surgical and Nonsurgical Consequences of the Wait-And-See Policy

A prospective study of the consequences of the wait-and-see policy in in patients with neuroradiologic diagnostic evidence of having vestibular schwannoma was conducted in a series of 123 patients (127 tumors) over a 20-year period, from 1973 to 1993. The mean follow-up period was 3.4 years, mean annual growth rate was 3.2 mm/year, mean annual volume growth rate was 0.72 ml/year, and mean annual relative growth rate was 41%. Tumor growth was observed in 90 (74%) patients (94 tumors), no growth was seen in 23 (18%) patients (23 tumors), and negative tumor growth was seen in 10 (8%) patients (10 tumors). Surgery due to tumor growth was performed in 35 (28%) patients (35 tumors), 7 (6%) patients (7 tumors) were treated with gamma-radiation and/or shunt insertion, 7 (6%) patients died of brain stem herniation induced by tumor compression, 9 (7%) patients died of non-tumor-related causes, 28 patients were classified as candidates for hearing preservation surgery, and 21 (75%) patients lost their candidacy during the observation period due to tumor growth and/or deterioration of hearing. The results may limit indications for allocation of patients with vestibular schwannoma to the wait-and-see group.

Sinonasal papillomas: A report of 82 cases in copenhagen county, including a longitudinal epidemiological and clinical study

The present epidemiological and clinical study comprises 82 patients with sinonasal papillomas diagnosed from 1975 to 1993. Histology showed 58 cases of inverted papillomas including 5 cases of associated carcinoma, 19 cases of exophytic papilloma, and 5 cases of columnar cell papilloma. The incidence of sinonasal papillomas in Copenhagen County was 0.74 per 100,000 inhabitants per year. The inverted and columnar cell papillomas were typically located in the middle meatus with a varying degree of involvement of the adjacent sinuses. The exophytic papillomas were predominantly located multicentrically on the nasal septum. Good results of treatment, especially with regard to inverted papillomas, were not correlated to the aggressiveness of surgery. A lateral rhinotomy with medial maxillectomy was performed as primary surgery in 28 patients. In 50% of these patients there were recurrences. The preliminary results of endonasal endoscopic surgery revealed a high success rate, i.e., no recurrences in 5 cases so far. The septal papillomas were typically resected by a simple endonasal procedure. There were recurrences in 66% of these cases. The midfacial degloving procedure may be advocated instead of or as a supplement to the lateral rhinotomy if the tumor cannot be visualized sufficiently by endoscopy. Smoking may dispose to sinonasal papillomas.

True incidence of vestibular schwannoma

BACKGROUND:The incidence of diagnosed sporadic unilateral vestibular schwannomas (VS) has increased, due primarily to more widespread access to magnetic resonance imaging. OBJECTIVE:To present updated epidemiological data on VS incidence, as well as patient age, hearing acuity, tumor size, and localization at diagnosis for the last 4 decades in an unselected population, with emphasis on developments in recent years. METHODS:From 1976 to 2008, 2283 new cases of VS were diagnosed and registered in a national database covering 5.0 to 5.5 million inhabitants. Incidence during the period, patient sex and age, data on hearing (pure tone average and speech discrimination), and tumor size at diagnosis were retrieved from the database. RESULTS:The incidence increased from 3.1 diagnosed VS per million per year in 1976 to a peak of 22.8 VS per million per year in 2004, which was followed by a decrease to 19.4 VS per million per year in 2008. Mean tumor size at diagnosis decreased from 30 mm in 1979 to 10 mm in 2008, whereas hearing acuity at diagnosis has improved over the years. CONCLUSION:After a steady increase over the last 4 decades, the incidence of vestibular schwannomas appears to have peaked and decreased in recent years, stabilizing at about 19 tumors per million per year. Whereas the sex ratio and age at diagnosis have remained grossly unchanged over the years, hearing has improved, and tumor size has decreased considerably.

The Estimated Incidence of Symptomatic Nasal Polyps

The objective of the present study was to establish the estimated incidence of symptomatic nasal polyps within a defined geographic area. Over a 6-year period all polyp patients diagnosed for the first time ( n ¾ 252; 174 males, 78 females) were prospectively registered at the study clinic. An estimated background population from which the patients were recruited was defined. Polyps were diagnosed by endoscopic examination. The mean estimated incidences for all age groups were 0.86 and 0.39 patients per thousand per year for males and females, respectively. The incidence increased with age, reaching peaks of 1.68 and 0.82 patients per thousand per year for males and females, respectively in the age group 50-59 years. The overall estimated incidence of symptomatic nasal polyps was 0.627 patients per thousand per year. Five percent of the patients had antrochoanal polyps and these patients had a lower mean age at diagnosis than the other patients, of whom 41% also had unilateral presentation at the time of diagnosis. This study seems to give a fairly reliable estimated incidence of symptomatic nasal polyps for different age groups and provides results that do not contradict prevalence studies in the literature, making it useful in a clinical context.

Epidemiology of acoustic neuromas

In Denmark one surgical team, during the last 7 years, has performed about 80 per cent of all acoustic neuroma surgery. Because of this centralization, in such a limited population as that of Denmark, we have attempted to make a epidemiological survey of all diagnosed tumours in the period from 1976 to 1983. Systematic and prospective records were made by the authors of all patients with translabyrinthine operations, and data on patients with suboccipital operations were collected retrospectively from the six neurosurgical departments in Denmark. The average annual incidence was 8 tumours per million inhabitants, with the highest incidence of approximately 13 tumours per million occurring in Copenhagen County. The incidence reported in previously published autopsy series is 800-900 times higher and the following may serve as an explanation for this enormous difference: Autopsy series are in all probability based on highly selected cases; they are predominantly based on elderly people and the incidence is not directly applicable to the population at large. Several of the silent tumours from the autopsy series were located in the cochlea or in the labyrinth and not in the internal ear canal. The conclusion from our study is that both the knowledge and data available at present are insufficient to serve as a basis for an actual calculation of incidence and prevalence of acoustic neuromas.(ABSTRACT TRUNCATED AT 250 WORDS)

Sensorineural hearing loss following chronic ear surgery

The incidence and characteristics of postoperative sensorineural hearing loss were analyzed in 2,303 cases of chronic otitis and its sequelae, representing our total series from 1965 to 1980. Sensorineural hearing loss occurred in a total of 1.2 % of cases: 0.5 % became totally deaf, and 0.7% acquired a high tone loss, most often at 4 kHz only. The incidence was highest in congenital malformations, granulating otitis and cholesteatoma, mastoidectomy (especially canal-down), and during the period from 1965 to 1974. The most common causes of anacusis were removal of cholesteatoma from the semicircular canal and removal of the fistula membrane. Different types of severe high tone loss are described and, in addition, 19 patients with mild high tone loss are discussed.

Efficacy of an aqueous and a powder formulation of nasal budesonide compared in patients with nasal polyps.

Nasal polyps are commonly treated surgically. Intranasal administration of topical corticosteroids has gained increased acceptance as a treatment alternative. The aim of our study was to compare the efficacy of treatment of two formulations of budesonide with placebo on nasal polyps. At four Danish clinics 138 patients suffering from moderate or severe nasal polyps were randomized to a twice daily treatment with Rhinocort® Aqua 128 μg, Rhinocort Turbuhaler® 140 μg or placebo (Astra Draco, Sweden) for 6 weeks. Polyp size (primary efficacy variable), nasal symptoms, sense of smell, and patients’ overall evaluation of treatment of efficacy were assessed by scores. Polyp size was reduced significantly in both budesonide treated groups compared with placebo, but there was no statistical difference between the two actively treated groups. Patients’ nasal symptom scores was significantly more reduced in the Aqua compared to the Turbuhaler treated group, and both reduced symptom scores were significantly better compared to placebo. Sense of smell was significantly improved in the actively treated groups compared to placebo. The proportion of patients rating substantial or total control over symptoms after 6 weeks treatment was 60.9% and 48.2% in the Aqua and Turbuhaler-treated groups, respectively, which was significantly better compared with 29.8% in the placebo-treated group. Rhinocort Aqua and Rhinocort Turbuhaler were equally well tolerated.

Origin of nasal polyps: an endoscopic autopsy study.

Objectives/Hypothesis To further elucidate the natural history, etiology, and pathogenesis of nasal polyps, the present study of their anatomical site of origin was undertaken. The possibility for preferred areas or certain patterns in the places of origin was also considered.