International Rhinologic Society Rhinology 0300-0729 50 3 2012 9 1 Irritated Noses 225 226 EN WJ Fokkens Department of Otorhinolaryngology, Academic Medical Center, Amsterdam, the Netherlands 1109 10.4193/Rhin We all suffer from an occasional sneeze, or a runny nose when bicycling or skiing. However, when these symptoms occur con- tinuously in our patients something is wrong and we call it hy- perreactivity. An obvious reason for hyperreactivity is allergy. However, about half of the patients visiting our clinics with symptoms of persistent rhinitis do not have allergy. Also in these non-allergic rhinitis patients hyperreactivity plays an im- portant role. The pathophysiology of non-allergic rhinitis seems to be heterogeneous ranging from inflammatory reactions like local allergy and NARES on one side and non-inflammatory forms of the disease like idiopathic rhinitis and gustatory rhini- tis on the other.

International Rhinologic Society Rhinology 0300-0729 50 3 2012 9 1 Up-date on neuro-immune mechanisms involved in allergic and non-allergic rhinitis 227 235 EN L. Van Gerven Department of Otorhinolaryngology, Head & Neck Surgery, University Hospitals Leuven, Leuven, Belgium G. Boeckxstaens P. Hellings 1080 10.4193/Rhin Non-allergic rhinitis (NAR) is a common disorder, which can be defined as chronic nasal inflammation, independent of systemic IgE-mediated mechanisms. Symptoms of NAR patients mimic those of allergic rhinitis (AR) patients. However, AR patients can easily be diagnosed with skin prick test or allergen-specific IgE measurements in the serum, whereas NAR patients form a heterogeneous group and are difficult to diagnose because of an extensive list of different phenotypes, all varying in severity, underlying etiology and type of inflammation. Characterization of those phenotypes, mechanisms and management of NAR represents one of the major unmet needs in the field of allergic and non-allergic diseases. This review aims at providing a comprehensive overview of the state of the art in classifying the NAR patients and focuses on the neuro-immune mechanisms involved in allergic and non-allergic rhinitis, including reflections on the pathophysiology and the currently available treatment options.

International Rhinologic Society Rhinology 0300-0729 50 3 2012 9 1 Trans-septal suturing technique in septoplasty: a systematic review and meta-analysis 236 245 EN V. Certal Department of Otorhinolaryngology, Hospital Sao Sebastiao, Sta Maria da Feira, Portugal, CINTESIS - Center for Research in Health Technologies and Information Systems, University of Porto, Porto, Portugal H. Silva T. Santos A. Correia C. Carvalho 1103 10.4193/Rhin STATEMENT OF THE PROBLEM: Trans-septal suturing techniques are routinely used to obviate the need for packing after septoplasty surgery. This study aimed to systematically assess the evidence for the efficacy and safety of suturing techniques after septoplasty. METHODS: A MEDLINE, Scopus, Cochrane Library, and ProQuest Dissertations & Thesis Database search, followed by extensive hand-searching for the identification of relevant studies. No time and language limitations were applied. Only prospective randomized controlled trials (RCTs) comparing trans-septal suturing techniques following septoplasty with conventional packing were included. For each outcome, risk difference and 95% confidence intervals (CIs) were calculated. Tests for heterogeneity and tests for publication bias were applied. RESULTS: Eight RCTs with 869 patients were included in the review. Postoperative pain and headache were significantly lower in the non-packing group. Conventional packing and trans-septal suturing technique appear to be equivalent with regard to postoperative haemorrhage risk, mucosal adhesions, septal perforation, septal haematoma and local infection. CONCLUSIONS: The evidence for the advantage of suturing techniques over conventional packing in septoplasty is now robust, and the use of suturing techniques as a first line intervention is becoming advisable.

International Rhinologic Society Rhinology 0300-0729 50 3 2012 9 1 Endoscopic sinus surgery training courses: benefit and problems - a multicentre evaluation to systematically improve surgical training 246 254 EN T. Braun Department of Otorhinolaryngology, Head and Neck Surgery, Ludwig Maximilian University, Munich, Germany C.S. Betz G.J. Ledderose M. Havel Department of ORLHNS, Munich University Hospital, Munich, Germany K. Stelter Department of ORLHNS, Munich University Hospital, Munich, Germany T. Kühnel G. Strauß J. Waschke T. Kirchner H.R. Briner D. Simmen M. Caversaccio P.J. Wormald N. Jones A. Leunig Department of Otorhinolaryngology, Head and Neck Surgery, Ludwig Maximilian University, Munich, Germany 1101 10.4193/Rhin BACKGROUND: The aim of this multicentre study was to systematically analyse the strengths and weaknesses in the surgical trai- ning for endoscopic sinus surgery (ESS) and identify measures that may improve training. METHODOLOGY: Using a structured questionnaire, 133 participants of ESS courses in seven centres in Germany, Switzerland and Australia were asked about their experiences during their dissection courses and how they perceived their course could be impro- ved. RESULTS: Gaining confidence in handling of instruments and endoscopes was only a problem for participants with little experi- ence in ESS. The majority of the participants, independent from their level of training, considered infundibulotomy and anterior ethmoidectomy as the easiest dissection steps, whilst surgery of the frontal sinus posed a considerable challenge for many surge- ons even those with a higher level of training. Participants with and without ESS experience thought that emphasis on anatomy was the most important improvement that could be made during their surgical training. Virtually all participants stated that the course improved their anatomical knowledge, their surgical skills and their confidence when performing ESS. CONCLUSIONS: ESS dissection courses are considered beneficial by surgical trainees. Participants felt that more emphasis on sinus anatomy in conjunction with private study is essential to maximize their skills in surgical dissection. For beginners with ESS, an infundibulotomy and anterior ethmoidectomy were thought to be the best initial procedures to help develop endoscopic surgical skills.

International Rhinologic Society Rhinology 0300-0729 50 3 2012 9 1 Quality of life in extended endonasal approaches for skull base tumours 255 261 EN C. Georgalas R. Badloe W. van Furth S. Reinartz W.J. Fokkens Department of Otorhinolaryngology, Academic Medical Centre, Amsterdam, The Netherlands 1102 10.4193/Rhin OBJECTIVE: To assess the quality of life (QOL) impact of extended endonasal approaches and nasoseptal flap reconstruction for benign skull base tumours METHODS: A random sample of 110 patients undergoing either limited endonasal transphenoidal hypophysectomy or extended endonasal approaches (trans-cribriform, trans-sellar, trans-tuberculum, trans-pterygoid) for the removal of benign skull base tumours were asked to complete Rhinosinusitis Outcome Measure (RSOM-31) questionnaire. RESULTS: A total of 91 patients returned the completed questionnaire. All patients in the limited approach group had pituitary adenomas, while patients in the extended group had a variety of tumours including adenomas with suprasellar or cavernous extension, chordomas, meningiomas, craniopharyngiomas and dermoids. Median time to completion of questionnaire was 1104 days in the limited group and 142 days in the extended approaches group. Although smell and headache were significantly worse in the group undergoing reconstruction with Haddad flap, there was no significant difference in overall, nasal, general, emotional or sleep quality of life between the two groups. Both smell and headache showed significant improvement with time. In linear regression, the single most important factor independently associated with overall worse RSOM-31 total scores was the presence of secreting adenomas. CONCLUSION: The use of nasoseptal flap appears to have a limited negative impact in nasal quality of life, mainly related to heada- che and reduced smell, both of which tend to improve with time. Hormone-secreting tumours have the most important adverse effect in quality of life extending in general, emotional, sleep and overall wellbeing, as reflected in RSOM 31 subscales.

International Rhinologic Society Rhinology 0300-0729 50 3 2012 9 1 Origin oriented management of inverted papilloma of the frontal sinus 262 268 EN R.H. Kamel Department of Otorhinolaryngology, Cairo University, Cairo, Egypt A.F. Abdel Fattah A.G. Awad 1099 10.4193/Rhin BACKGROUND: Despite the great progress in endoscopic management of inverted papilloma (IP), involvement of the frontal sinus (FS) remains a challenge. METHODOLOGY: Six cases of FS IP were assessed. Extent of surgery included simple frontal recess clearance, extended frontal sinusotomy, and modified Lothrop approach. There was no need for adjuvant frontal trephination or an external osteoplastic flap. RESULTS: FS involvement was observed in 6 out of 119 cases of IP (5%). In one case, IP was originating from the FS and in four it was extending to the FS. The sixth case had a wide origin from the anterior ethmoid and FS. Complete resection of FS IP was achieved in all cases with a single incidence of CSF leak. No recurrence was identified after a follow-up period of an average of 27 months. CONCLUSIONS: FS IP originating outside FS can be delivered transnasally with or without frontal ostium widening and preserving FS mucosa and bone. Inverted papillomata originating from FS proper and those with origin from inside and outside the FS can also be resected tranasnasally after widening of the frontal ostium with removal of surrounding mucosa and drilling or curettage of underlying bone at attachment sites.

International Rhinologic Society Rhinology 0300-0729 50 3 2012 9 1 Sinus fungal balls: characteristics and management in patients with host factors for invasive infection 269 276 EN G. Toussain Hopital intercommunal, service d'ORL et de chirurgie cervico-faciale, Creteil, F-94010, France F. Botterel I.A. Alsamad F. Zerah-Lancner V. Prulière-Escabasse A. Coste J.F. Papon 1107 10.4193/Rhin BACKGROUND: The characteristics of sinus fungal ball (SFB), classically considered being a non-invasive form of fungal infection, in patients with host factors for invasive fungal infection (IFI) are unknown. OBJECTIVE: To characterize SFB and their management in patients with host factors for IFI. METHODOLOGY: Retrospective single-centre study of the clinical, radiology, histology and mycology records of patients treated for SFB between 1997 and 2007. Patients with and without host factors for IFI were compared. RESULTS: One hundred eighty one patients were classified into two groups: 19 (group 1) with and 162 (group 2) without host fac- tors for IFI. In group 1, SFB were asymptomatic in 26.3% of the cases, ethmoido-sphenoidal sinuses were more frequently involved than in group 2 and fungal culture was positive in 37.5% of the cases. The main species was Aspergillus sp. in both groups. Four cases of complicated SFB were observed, only in patients of group 1. Cure without recurrence was obtained in both groups by endonasal surgery, combined with triazole therapy in complicated forms with osteolysis. CONCLUSION: In patients with host factors for IFI, SFB more frequently involves deep sinuses and can be complicated by clinical signs suggestive of invasion and radiological signs of osteolysis, with no histological evidence of fungal invasion.

International Rhinologic Society Rhinology 0300-0729 50 3 2012 9 1 Silent threat? A retrospective study of screening practices for pulmonary arteriovenous malformations in patients with hereditary haemorrhagic telangiectasia 277 283 EN M.M. Verkerk University College London Medical School, London, United Kingdom C.L. Shovlin V.J. Lund Royal National Throat Nose and Ear Hospital, London, United Kingdom. 1097 10.4193/Rhin BACKGROUND: Patients with hereditary haemorrhagic telangiectasia (HHT) are at risk of pulmonary arteriovenous malformations (PAVMs) that may be complicated by stroke and brain abscess. ENT surgeons are well placed to direct patients to screening, which was recommended for all HHT patients in recently published international guidelines. METHODOLOGY/PRINCIPAL: A retrospective study of patients with known HHT was performed based on responses to a telephone questionnaire. Epistaxis was assessed using a validated epistaxis severity scoring system. RESULTS: 123 patients responded, with ages ranging from 14-86 years (mean 57 years). 80% of patients experienced their first symptom of HHT by 30 years old. Epistaxis was assessed at time of questionnaire as mild (26 patients), moderate (52 patients) or severe (45 patients). 71 patients (57.7% of total) underwent screening for PAVMs. 30 patients (42.2% of screened individuals) reported PAVMs detected by screening. 18 patients received treatment and 12 patients were found to have PAVMs too small for treatment. The modal screening method was computed tomography (CT, 58 patients) and the majority of patients with treatable PAVMs received trans-catheter embolisation (15 patients). Only 9 patients reported being under long term follow up for PAVMs. Shortness of breath (70.0% vs 41.5%, p<0.05) and migraine (43.3% vs 24.4%, p<0.05) were more common amongst patients found to have PAVMs than those without PAVMs. There was no difference in age of onset of HHT symptoms or epistaxis severity between patients with PAVMs and those without. CONCLUSIONS: PAVMs are common in HHT patients and carry a risk of morbidity and mortality. Safe and effective treatment exists for PAVMs although a significant minority of patients has received no screening to date. Clinicians should refer all patients for screening regardless of symptoms.

International Rhinologic Society Rhinology 0300-0729 50 3 2012 9 1 Treatment of smell loss with systemic methylprednisolone 284 289 EN V.A. Schriever Smell & Taste Clinic, Department of Otorhinolaryngology, University of Dresden Medical School, Dresden, Germany C. Merkonidis N. Gupta C. Hummel T. Hummel 1082 10.4193/Rhin BACKGROUND AND AIM: Olfactory dysfunction is a common complaint in a large number of people. As the aetiologies of olfactory dysfunction vary greatly so do the treatment approaches. The aim of this retrospective study was to evaluate treatment with systemic corticosteroids, particularly focusing on its effectiveness on the different olfactory dysfunction aetiologies. Although a prospective randomized control trail is preferred for such an investigation, using the current approach, we were able to test a very large patient population. MATERIAL AND METHODS: A total of 425 patients with olfactory dysfunction were treated with systemic corticosteroids for 14 days. Olfactory performance was measured using the 'Sniffin' Sticks' battery before and after the treatment. RESULTS: The treatment with systemic corticosteroids significantly increased the performance on the TDI score and on each of the three subtests; threshold, discrimination and identification. In 26.6% of the patients improvement of more than six points of the TDI score was observed. The treatment proved to be more effective in patients with sinunasal olfactory dysfunction, where this percentage increased to 36.7, compared to other aetiologies. In addition, the increase in olfactory function was negatively correlated with the TDI score before the treatment. CONCLUSION: This study confirms the effectiveness of systemic corticosteroids on olfactory dysfunction in a large patient population. Specifically, the results show that treatment is: (a) more effective in patients with sinunasal than in patients with idiopathic olfactory dysfunction, (b) most effective in patients with sinunasal disease with nasal polyps, and (c), at best, effective in half of the patients. The current study may provide help in counselling patients.

International Rhinologic Society Rhinology 0300-0729 50 3 2012 9 1 Investigation of the topographical differences in somatosensory sensitivity of the human nasal mucosa 290 293 EN M. Scheibe Smell & Taste Clinic, Department of Otorhinolaryngology, University of Dresden Medical School, Dresden, Germany A. Schmidt T. Hummel 1100 10.4193/Rhin Background: Previous investigations in humans suggest topographical differences in intranasal trigeminal chemosensitivity with the highest sensitivity in the anterior part. The present study aimed to investigate whether different sites in the human nasal mucosa react differently to unspecific electrical stimuli. Methology: Participants were 50 young, healthy volunteers (24 men, 26 women; age 22-38 years). Detection and pain threshold of electrical trigeminal stimuli were investigated at 5 different sites: anterior septum, posterior septum, inferior turbinate, middle turbinate and anterior lateral wall. Results: In healthy subjects, a significantly higher trigeminal sensitivity was found at the anterior parts of the nose compared to the posterior part. There was a similar distribution pattern of the sensitivity for detection and pain thresholds. Conclusions: Results suggest that there are consistent topographical differences in the arrangement of trigeminal receptors of the human nasal cavity; highest somatosensory sensitivity seems to be located in the anterior part. This finding is compatible with the idea that the trigeminal system acts as a sentinel of the human airways with regard to toxic agents.

International Rhinologic Society Rhinology 0300-0729 50 3 2012 9 1 Nasal dysfunction induced by chlorinate water in competitive swimmers 294 298 EN G. Ottaviano Department of Neurosciences, Otolaryngology Section, University of Padova, Padova, Italy A. Staffieri P. Stritoni A. Ermolao S. Coles M. Zaccaria G. Marioni 1094 10.4193/Rhin AIMS: Swimmers commonly complain of nasal symptoms probably due to mucosal irritation caused by chlorinated water. The aim of the present prospective study was to investigate changes in nasal function and cytology in a cohort of 15 volunteer competitive swimmers, as compared with a control group of 15 competitive athletes practicing other sports. METHODS: Olfactory threshold for n-butanol was measured in a population of competitive swimmers. Changes in nasal function and cytology were compared between the two groups of volunteer competitive athletes. RESULTS: There were no significant differences between the two groups in terms of mean 20-Item Sino-Nasal Outcome Test scores, peak nasal inspiratory flow, pulmonary peak expiratory flow, or total nasal resistance on anterior active rhinomanometry. Nasal mucociliary transport time (MCTt) was significantly shorter for the non-swimmers than for the swimmers. The mean olfactory threshold for n-butanol in the swimmers was significantly lower than in the other group of athletes. CONCLUSIONS: Data seem to confirm the utility of MCTt in studying nasal mucosa damage caused by chlorinated water. The present results also support the hypothesis of a role for the olfactory threshold in evaluating damage to the olfactory mucosa exposed to chlorinated water.

International Rhinologic Society Rhinology 0300-0729 50 3 2012 9 1 Osteitic bone: a surrogate marker of eosinophilia in chronic rhinosinusitis 299 305 EN K. Snidvongs Australian School of Advanced Medicine, Macquarie University Hospital, Sydney, NSW, Australia R. McLachlan D. Chin Department of Otolaryngology Head & Neck Surgery, Changi General Hospital, Singapore E. Pratt Faculty of Medicine, The University of Sydney, Sydney, NSW, Australia R. Sacks Department of Otolaryngology, Concord General Hospital, Sydney, NSW, Australia P. Earls R.J. Harvey 1108 10.4193/Rhin BACKGROUND: Causes of osteitis in chronic rhinosinusitis (CRS) other than previous surgery are poorly defined. Patients with eosi- nophilic CRS (ECRS) have more severe disease and poorer outcomes despite repeated surgery. Associations between osteitis and markers of ECRS are not well described. METHODS: A cross-sectional study of CRS patients undergoing sinus surgery was conducted. Osteitis was scored radiologically using previously published measures. Associations between osteitis and histopathology, symptoms, endoscopy, CT mucosal score and seromarkers were analyzed. RESULTS: Eighty-eight patients were assessed of whom forty-five had osteitis. Patients undergoing revision surgery recorded higher osteitis scores. Patients with mucosal eosinophilia had higher osteitis score than those without. Patients with osteitis had higher serum eosinophil. Similar relationships were also found in primary surgery. Osteitis was associated with endoscopic and radiologic, but not symptomatic disease severity. CONCLUSIONS: Osteitis is associated with tissue and serum eosinophilia in both patients with and without prior surgery. Patients with these features may benefit from post-operative corticosteroid therapy to prevent osteitis.

International Rhinologic Society Rhinology 0300-0729 50 3 2012 9 1 A double-blind randomised controlled trial of gloved versus ungloved merocel middle meatal spacers for endoscopic sinus surgery 306 310 EN E. Akbari St. Paul's Sinus Centre, St. Paul's Hospital, Vancouver, British Columbia, Canada C.M. Philpott A.J. Ostry A. Clark A.R. Javer 1095 10.4193/Rhin BACKGROUND: Middle meatal spacers are commonly used following endoscopic sinus surgery to prevent post-operative bleeding and lateralization of the middle turbinates. The effects of nasal packing on post-operative sinonasal mucosal healing remain unknown in humans. OBJECTIVE: This study aims to compare the histopathalogical effects of Merocel and Merocel covered with a finger glove on mucosal healing, and patients' discomfort immediately post-operatively after endoscopic sinus surgery and at removal of the nasal packing. METHODS: Thirty-seven patients with chronic rhinosinusitis undergoing bilateral endoscopic sinus surgery were enrolled in a prospective study. Patients were randomized and blinded to receive Merocel middle meatal spacer (MMMS) in one nostril and finger glove Merocel middle meatal spacer (FGMMS) in the contra lateral side. Patients were seen on post-operative day 6, and completed a visual analogue score reporting the post-operative discomfort from nasal packing on each side. Following the removal of nasal packing, patients indicated which side caused more discomfort on removal. Biopsies were taken from the middle turbinates and sent to a blinded pathologist who scored the level of mucosal inflammation from 0 - 4. RESULTS: There was no statistically significant difference between MMMS and FGMMS in regards to their effect on sinonasal mucosal inflammation and discomfort post-operatively. A statistically significant difference was noted with respect to discomfort at removal with the uncovered Merocel more likely to cause discomfort when compared to the Merocel covered in a glove finger. CONCLUSION: MMMS and FGMMS are equivalent in the amount of sinonasal mucosal inflammation and discomfort post endoscopic sinus surgery. However, the main advantage of the FGMMS was a significant reduction in pain on removal when compared with the MMMS.

International Rhinologic Society Rhinology 0300-0729 50 3 2012 9 1 Deviated nasal septum hinders intranasal sprays: a computer simulation study 311 318 EN D.O. Frank Department of Otolaryngology/Head and Neck Surgery, University of North Carolina, Chapel Hill, North Carolina, U.S.A. J.S. Kimbell Department of Otolaryngology/Head and Neck Surgery, University of North Carolina, Chapel Hill, North Carolina, U.S.A. D. Cannon S.S. Pawar J.S. Rhee 1112 10.4193/Rhin BACKGROUND: This study investigates how deviated nasal septum affects the quantity and distribution of spray particles, and examines the effects of inspiratory airflow and head position on particle transport. METHODS: Deposition of spray particles was analysed using a three-dimensional computational fluid dynamics model created from a computed tomography scan of a human nose with leftward septal deviation and a right inferior turbinate hypertrophy. Five simulations were conducted using FluentTM software, with particle sizes ranging from 20-110 μm, a spray speed of 3 m/s, plume angle of 68°, and with steady state inspiratory airflow either present (15.7 L/min) or absent at varying head positions. RESULTS: With inspiratory airflow present, posterior deposition on the obstructed side was approximately four times less than the contralateral side, regardless of head position, and was statistically significant. When airflow was absent, predicted deposition beyond the nasal valve on the left and right sides were between 16% and 69% lower and positively influenced by a dependent head position. CONCLUSION: Simulations predicted that septal deviation significantly diminished drug delivery on the obstructed side. Furthermore, increased particle penetration was associated with presence of nasal airflow. Head position is an important factor in particle deposition patterns when inspiratory airflow is absent.

International Rhinologic Society Rhinology 0300-0729 50 3 2012 9 1 Seasonality and incidental sinus abnormality reporting on MRI in an Australian climate 319 324 EN A. del Rio Department of Medicine, University of Melbourne, Australia N. Trost C. Tartaglia S.J. O’Leary P. Michael 1098 10.4193/Rhin BACKGROUND: Incidental sinus mucosal abnormalities on MRI are a common finding. This study aims to investigate seasonality and reporting of these findings. METHODOLOGY: Prospective, cross-sectional study of adult patients presenting for neuro-radiological assessment using MRI. 173 patients were recruited over 'winter' and 'summer' collection periods (mean maximum temperature 14.5°C and 24.3°C, respectively). Patients were classified as symptomatic for rhinosinusitis according to the European Position Paper on Rhinosinusitis and Nasal Polyps 2007 definition. A modified Lund Mackay score was used to assess sinus pathology. Mucosal thickening of > 3mm was considered pathological. Radiologist reports were reviewed for mention of incidental sinus abnormalities. RESULTS: There was an incidental rate of 58.1% overall, with significantly more sinus abnormalities in winter. Sinus abnormalities were mentioned in 8.1% of radiologist reports, half of which were in asymptomatic patients. There were significantly more sinus abnormalities amongst symptomatic patients. CONCLUSIONS: Incidental sinus changes on MRI are a common finding and are often reported on by radiologists. However, they bear little association with symptoms. Their prevalence is influenced by season and thus their significance is greater during cooler months. Specialist referral should be reserved for symptomatic patients that have failed medical therapy.

International Rhinologic Society Rhinology 0300-0729 50 3 2012 9 1 Extranodal natural killer/T-cell lymphoma: a diagnostic dilemma 325 331 EN H. Yanagi Department of Otolaryngology-Head and Neck Surgery, Hokkaido University Graduate School of Medicine, Sapporo, Hokkaido, Japan Y. Nakamaru D. Takagi K. Kubota S. Fukuda 1096 10.4193/Rhin BACKGROUND: The diagnosis of extranodal natural killer (NK)/T-cell lymphoma (NK/T-cell lymphoma) is often difficult and any delay in its diagnosis leads to a worsened prognosis. We analysed the factors that make the diagnosis of this type of tumour difficult. METHODOLOGY/PRINCIPAL: We retrospectively reviewed the medical records of 20 patients with NK/T-cell lymphoma treated in our department, and assessed the clinical features and laboratory findings of the cases. Moreover, we classified factors related to delays in diagnosing NK/T cell lymphoma as follows: (1) insufficient specimen size, (2) massive necrosis, (3) large number of inflammatory cells, and (4) poor atypia. We selected cases requiring two or more biopsies for correct diagnosis and checked which factors were the main cause of misdiagnosis. RESULTS: The average period required for a correct diagnosis was 12.8 months. The most frequent factor leading to diagnostic delay was inflammatory cell infiltration. Massive necrosis and poor atypia were also important factors in diagnostic delay. CONCLUSIONS: In cases with necrotic lesions of the nose or pharynx, the possibility of NK/T cell lymphoma should be explored and samples, of as large a size as possible, should be obtained together with EBER-ISH for pathological examination. Repeat biopsies should also be performed for diagnosis.