Development and calibration of a high dynamic range and autonomous ocean-light instrument to measure sub-surface profiles in ice-covered waters.

The optical chain and logger (OptiCAL) is an autonomous ice-tethered observatory equipped with multiple light sensors for mapping the variation of light with depth. We describe the instrument and present an ensemble calibration for downwelling irradiance E P A R in [µm o l m -2 s -1]. Results from a long-term deployment in the Arctic Ocean demonstrate that the OptiCAL can cover the high dynamic range of under-ice light levels from July to November and produce realistic values in terms of magnitude when compared to modeled surface irradiance. Transient features of raised light levels at specific depths associated with nearby leads in the ice underline the importance of depth-resolved light measurements.

All-sky camera system providing high temporal resolution annual time series of irradiance in the Arctic.

The ArcLight observatory provides hourly continuous time series of light regime data (intensity, spectral composition, and photoperiod) from the Arctic, Svalbard at 79° N. Until now, no complete annual time series of biologically relevant light has been provided from the high Arctic due to insufficient sensitivity of commercial light sensors during the Polar Night. We describe a camera system providing all-sky images and the corresponding integrated spectral irradiance (EPAR) in energy or quanta units, throughout a complete annual cycle. We present hourly-diel-annual dynamics from 2017 to 2020 of irradiance and its relation to weather conditions, sun and moon trajectories.

Multicenter experiences in temporal bone cancer surgery based on 89 cases.

OBJECTIVE: To present outcomes of extensive surgery: lateral, subtotal, total petrosectomies in patients with temporal bone invasion resulting from specific primary cancers. STUDY DESIGN: Retrospective case review. SETTING: Four tertiary referral centers. MATERIAL: 89 patients with cancer of the temporal bone treated between January 2006 and December 2010. INTERVENTION: Multidisciplinary team approach including surgical resection, reconstruction, and postoperative radiotherapy. MAIN OUTCOME MEASURE: Disease-specific survival, overall survival. RESULTS: In 27.0% of the patients, relapse was reported, with an average of 6.3 months after surgery; 31 patients (34.8%) died during the follow-up. The average mortality was 22.1 months. Fifty-four patients (58.7%) stayed alive during the time of observation. The average survival time was 42.0 months. The median time of survival with relapse was 12 months (range: 1-51 months). The three-year disease-free rate was 38.0% and the overall survival rate was 58.7%. CONCLUSIONS: Petrosectomy is an effective treatment for malignant temporal bone invasion. The probability of a good outcome was statistically decreased with a high T grade, positive margins, and salvage surgery. Younger age is connected with better prognosis. One of the major tasks remains to improve detection and to shorten the time to diagnosis, keeping in mind that symptoms are insidious and in younger people, the time before diagnosis was longer.

Sialendoscopy and sialendoscopically-assisted operations in the treatment of lithiasis of the submandibular and parotid glands: our experience of 239 cases.

We present the results of treatment of sialolithiasis of the submandibular and parotid glands using sialendoscopy and sialendoscopy-assisted surgery. Between 2009-2013, 397 consecutive patients (mean (range) age 48 (18-76) years) were treated for obstructive diseases of the major salivary glands (sialolithiasis n=239, 175 submandibular and 64 parotid). In a total of 175 patients with 191 stones in the submandibular gland treated by endoscopic retrieval or surgical release, 149 patients (85%) were rendered free of stones (by sialendoscopy alone n=82, and sialendoscopy with operation n=67) Twenty patients (11%) had residual stones and 6 patients (4%) required excisionof the gland. Sixty-four patients had 71 stones removed from the parotid gland by endoscopic retrieval or surgical release and 43 (67%) were free of stones (by sialendoscopy alone n=25, and sialendoscopy with operation n=18). Twenty patients (31%) had residual stones and one (2%) required removal of the gland. In the group of patients whose stones were removed endoscopically, the effectiveness of sialendoscopy was 87% and 85%, respectively. We confirm that sialendoscopy and sialendoscopy-assisted removal is the current treatment of choice for stones in the submandibular and parotid glands. The indications for excision of the gland are becoming less common as first-line treatment, although it is still indispensable in some cases.

Treatment of Parotid Malignancies­10 Years of Experience.

PURPOSE: Operative treatment is the main treatment option for parotid gland tumors. The purpose of this study was to present the authors' experience in the operative treatment of parotid gland malignant tumors, especially regarding feasibility and techniques in the most advanced cases. MATERIALS AND METHODS: This is a retrospective cohort study of parotid malignancies. The study included patients treated at the authors' university clinic from 2000 through 2010. The primary predictor variable was stage of disease. The primary outcome variables were 3- and 5-year overall and disease-free survival rates. The secondary predictor variables were nodal status, distant metastases, status of the facial nerve (FN), tumor diameter, extraparotid tumor extension, histology, and surgical procedure. The outcome variable was survival rate. Data were analyzed by χ(2) tests. RESULTS: Of 867 parotid tumors, 103 patients with malignancies (47 female, 56 male; 12 to 88 yr old) underwent 24 partial lateral, 34 lateral, 39 total, and 6 extended parotidectomies. The 3- and 5-year overall survival and 3- and 5-year disease-free survival rates for stages T1 and T2 were 100, 99, 91, and 85%, respectively, and those for stages T3 and T4 were 100, 70, 48, and 34%, respectively. Overall and disease-free survival rates were influenced by FN paralysis and histologic type. CONCLUSIONS: Final oncologic outcomes, recurrence, and survival rates in parotid malignancies are considerably affected by local tumor stage, malignancy, and FN paralysis before treatment. Infiltration of adjacent structures is not connected with a poorer prognosis as long as an extended parotidectomy is performed.

Molecular signaling of the HMGB1/RAGE axis contributes to cholesteatoma pathogenesis.

UNLABELLED: Cholesteatoma represents progressive expansion of the keratinizing squamous epithelium in the middle ear with subsequent chronic inflammation in subepithelial connective tissues. The hypothesis was tested that receptor for advanced glycation endproduct (RAGE) and its ligand, high-mobility box 1 (HMGB1), are overexpressed in cholesteatoma, and the RAGE/HMGB1 axis might contribute to its pathogenesis. Cholesteatoma samples (n = 36) and 27 normal skin specimens were studied by immunohistochemistry (IHC) for HMGB1 and RAGE expression. Effects of HMGB1 signaling on proliferation, migration, cytokine production, and apoptosis of human immortalized keratinocytes (HaCaTs) and normal keratinocytes were studied by quantitative reverse transcription (qRT)-PCR, IHC, Western blots, and flow cytometry after cell co-incubation with HMGB1. While all studied tissues expressed HMGB1, its expression was higher in cholesteatoma than in normal skin (p < 0.0001). All cases of cholesteatoma also showed elevated RAGE expression levels, and only 7/27 (26 %) of normal skin specimens were weakly positive for RAGE. Proliferation and migration of HaCaT cells incubated with HMGB1 were up-regulated (p < 0.05). HMGB1 also prevented HaCaT cell apoptosis and induced activation of several molecular signaling pathways in keratinocytes. The data suggest that in cholesteatoma, HMGB1 released from stressed or necrotic epithelial cells and binding to RAGE overexpressed in keratinocytes initiates molecular signaling that culminates in pro-inflammatory cytokine release and chronic inflammation. KEY MESSAGE: HMGB1 signaling engages multiple activation pathways in RAGE-positive keratinocytes. HMGB1 protects RAGE-positive keratinocytes from drug-induced apoptosis. Keratinocyte proliferation is controlled via RAGE and HMGB1 molecular signaling. Molecular signaling of the HMGB1/RAGE axis contributes to cholesteatoma pathogenesis.

Sonoelastography--a useful adjunct for parotid gland ultrasound assessment in patients suffering from chronic inflammation.

BACKGROUND: Shear wave elastography (SWE) is widely used in breast, liver, prostate and thyroid evaluations. Elastography provides additional information if used to assess parotid gland pathology. We assessed parotid glands by means of SWE to compare the parenchyma properties in different types of inflammation. MATERIAL/METHODS: Prospective analysis included 78 consecutive patients with parotid gland pathology: sialolithiasis (33), Stensen's duct stenosis (15), chronic inflammation (10), and primary Sjögren syndrome (pSS) (20) treated at the Department of Otolaryngology, Head and Neck Surgery of PUMS. The primary predictor variable was type of parotid pathology, and secondary predictor variables were patient age and the duration and intensity of complaints. Ultrasound pictures were compared with elastography values of parotid parenchyma. RESULTS: Mean elasticity values for pSS (111 Kilopascals (kPa), Stensen's duct stenosis (63 kPa), sialolithiasis (82 kPa), and chronic inflammation (77 kPa) were significantly higher than the mean value for healthy patients (24 kPa). Elasticity increased proportionally to the intensity of complaints: mild (51 kPa), moderate (78 kPa), and strong (90 kPa). Increased elasticity did not correspond with ultrasonographic pictures. In pSS the parenchyma was almost twice as stiff as in chronic inflammation (p=0.02), although subjective complaints were mostly mild or moderate, and the ultrasonographic picture did not present features of fibrosis. CONCLUSIONS: Sonoelastography, by improving routine ultrasonographic assessment, might be a useful tool for parotid evaluations during the course of chronic inflammation. An extraordinarily high degree of stiffness was revealed in pSS despite lack of fibrosis by ultrasonography and moderate subjective complaints, suggesting that sonoelastography could be a valuable diagnostic tool.

Shear wave elastography: a new noninvasive tool to assess the intensity of fibrosis of irradiated salivary glands in head and neck cancer patients.

The aim of the study was to assess salivary gland parenchyma by means of sonoelastography in patients irradiated for head and neck squamous cell carcinoma (HNSCC). The studied group consisted of 52 patients after radiotherapy (RT) and 54 healthy volunteers. All of the former were treated for advanced larynx (40), oropharynx (9), or maxilla (3) squamous cancers and suffered from chronic dryness. Ultrasonography (US) and elastography (ES) were performed, as well as an assessment of the amount of saliva and Common Terminology Criteria for Adverse Events (CTCAE) scale. There was a statistical difference between ES values in the RT group and in the controls for parotid glands (41.7 kPa versus 26.03 kPa, P = 0.0018) and for submandibular glands (37.6 kPa versus 22.4 kPa; P = 0.005). There was a significant correlation between the CTCAE scores and objective saliva amount (P = 0.0005), and the median amount of saliva in the examined group was lower than in the reference group (1.86 g versus 2.75 g, P = 0.0006). In conclusion sonoelastography adds a new parameter to ultrasonography in "one touch examination" and may be a useful tool for major salivary gland evaluation during the radiotherapy course and follow-up period.

Fully endoscopic resection of juvenile nasopharyngeal angiofibroma - own experience and clinical outcomes.

OBJECTIVES: The treatment of choice in juvenile nasopharyngeal angiofibroma (JNA) is surgery - nowadays endoscopic techniques. The aim of the study was to present the results of endoscopic treatment in patients diagnosed with juvenile angiofibroma. MATERIALS AND METHODS: In this retrospective case series, 10 patients with a diagnosis of JNA treated at the Department of Otolaryngology of the Medical University in Poznan from 2006 to June 2013 were included. The age of patients were between 11 and 19 years old (14.6 on average). In 9 out of 10 patients the treatment was preceded by embolization. The surgery used the endoscopic approach through one nostril and the four-handed technique. RESULTS: Total resection was possible in all cases. Blood loss ranged from 100 to 250 ml. Post-operative hospitalization lasted from 3 to 5 days (3.3 days on average). Recurrence was reported in one patient. The observation lasted from six months to seven years (3.55 on average). CONCLUSIONS: Endoscopic resection of juvenile angiofibroma is safe for the patient. Moreover, if the evaluation of the tumour size and staging is correct, the ability of total removal of the tumour is very high. It is also connected with small blood loss, short hospital stay and good cosmetic effects.

Radiotherapy induced xerostomia: mechanisms, diagnostics, prevention and treatment--evidence based up to 2013.

Definition and prevalence of xerostomia were shortly presented. Radiosensitivity of the salivary glands, mechanism, diagnostics, and possible prediction methods of the intensity of xerostomia in the pre-radiotherapy period are widely discussed. Prevention of xerostomia: salivary gland sparing radiotherapy, cytoprotective agents, preservation by stimulation with cholinergic muscarinic agonists, surgical transfer of submandibular glands according to ASCO Management Guidelines and Quality of Life Recommendations were cited. Oral Care Study Group (2010) therapeutic approaches for relieving xerostomia are referred. Current therapies, restricted to symptom relief such as oral hygiene with fluoride agents, antimicrobials to prevent dental caries, saliva substitutes to relieve symptoms, and sialogenic agents to stimulate saliva were also discussed.

Sialendoscopy - a diagnostic and therapeutic approach subjectively rated by patients.

INTRODUCTION: Sialendoscopy is a miniinvasive procedure which shows the excretory ducts of the salivary glands. AIM: To evaluate patient satisfaction with sialendoscopy in submandibular and parotid gland sialolithiasis. MATERIAL AND METHODS: The study group included 100 consecutive patients with sialolithiasis, treated by means of sialendoscopy. The analysis was designed prospectively. The patients answered closed questions of our own, in-house made questionnaire. RESULTS: The number of sialendoscopic procedures necessary for symptom resolution ranged from 1 to 3. The mean value was 1.2 and the median was 1. In 64 patients (64%) one procedure was sufficient for symptom resolution, while 10 (10%) and 8 (8%) patients required 2 and even 3 procedures, respectively. Sixty-three patients (63%) did not report any postoperative complications; 33 patients (33%) reported transient swelling of the submandibular region and 4 patients (4%) reported inflammation of the salivary gland. The level of treatment efficacy was 82%. Among 53 patients treated using sialendoscopy for the first time 92.3% rated this approach subjectively as a very good or good technique, whereas among 47 patients who had previously undergone non-endoscopic treatment, this percentage increased to 96.4%. The general level of satisfaction with the applied method did not depend on the age, gender, duration of ailments, the number of previously performed procedures or the number of sialendoscopic procedures necessary to obtain improvement and postoperative complications. CONCLUSIONS: Sialendoscopy may be performed practically in any case without risking the patient's discomfort or unpleasant experience. Assessment of sialendoscopy by the patients confirmed the minimally invasive character of this technique.

Stensen's duct injuries: the role of sialendoscopy and adjuvant botulinum toxin injection.

INTRODUCTION: Stensen's duct injuries are uncommon but troublesome sequelae of facial surgery or other external traumas. AIM: To investigate the feasibility of sialendoscopic control of Stensen's duct in iatrogenic injuries and the efficiency of botulinum toxin adjuvant therapy. MATERIAL AND METHODS: In 2008 and 2010, 5 patients with parotid sialoceles or fistulas, infrequent complications after plastic surgery or trauma, were treated in a single institution, Poznan University of Medical Sciences ENT Department. The group consisted of 5 patients with diagnosed Stensen's duct injuries, which were post-surgery and post-traumatic sequelae. All were treated by means of open surgery. Botulinum toxin injection was administered during the procedure to decrease the saliva secretion and to improve the healing process. A sialendoscopy was performed to control the lumen of the junction after the duct injury was repaired. RESULTS: Complete healing of the fistulas and sialoceles after the reparative surgery followed by a single botulinum toxin application was observed in all patients within 10-14 days. No side effects were noticed. CONCLUSIONS: Our findings suggest that sialendoscopy is a valuable tool and an important step of control in the surgery of parotid duct injuries and the injection of botulinum toxin is an effective and safe second-line treatment.

Value of open horizontal glottectomy in the treatment for T1b glottic cancer with anterior commissure involvement.

BACKGROUND: The aim of the study was to evaluate the treatment outcomes in the group of 108 T1b glottic cancer patients with the anterior commissure involvement treated with open horizontal glottectomy and to compare them with transoral laser microsurgery (TLM) or primary radiotherapy (XRT) results from the literature review. METHODS: Status of surgical margins, local and nodal recurrence, organ preservation and survival rates, functional outcomes were major end points of interest. RESULTS: Recurrence rate was 16.7% and was correlated with histologically confirmed prelaryngeal node metastases. Salvage laryngectomy was performed in 10 patients, organ preservation rate was 90.7%. Mean survival was 41.9 months, while 5-year overall survival 97.2%. CONCLUSIONS: Local control and survival rates presented by the authors are comparable or even better than in TLM procedures or XRT outcomes from the literature. Positive prelaryngeal lymph nodes constituted a significant prognostic factor for nodal and local recurrence in the analyzed group.

Algorithm changes in treatment of submandibular gland sialolithiasis.

Our research was conducted to determine the algorithm changes during the treatment of submandibular sialolithiasis. Two time periods were compared between 2004-2008 and 2009-2012. The turning point was December 2008, when sialendoscopy procedure was introduced. In the first period, 48 patients were treated: 31 outpatient duct incisions with stone evacuation and 17 surgical excision of submandibular gland. In the second period, 207 sialendoscopy procedures were performed on 197 patients. Out of this particular group, 158 patients were diagnosed with pathological obstruction of salivary glands and 64 of them were confirmed to have sialolithiasis of submandibular gland. Deposits of calcifications in 40 individuals (62.5 %) affected by sialolithiasis were removed endoscopically; however, in 21 patients, due to the increased circumference of the stone, the intimate association of deposits within the wall of the duct along with its presence inside the deep portions of the gland, double approach (incision of the floor of the mouth in hilar area and sialendoscopy) was performed. Three individuals had their salivary glands totally removed due to the presence of calcified deposits within the glandular parenchyma. Our results allow us to affirm that sialendoscopy is the current treatment of choice for submandibular glands affected by sialoliths. Indication for a complete removal of the gland is becoming uncommon as a first line treatment although still indispensable in chosen cases.

[MALT-type parotid lymphoma--a case report and the review of the literature]. / Chloniak typu MALT slinianki przyusznej--opis przypadku i przeglad pismiennictwa.

Primary lymphomas of the salivary glands are rare. It is estimated that they constitute no more than 5% of all lymphomas in different locations. The most common subtype developing in parotid glands is marginal zone B-cell mucosa associated lymphoid tissue type lymphoma (MALT) that belongs to a group of low-grade tumours. There are many factors associated with the incidence of that proliferative process: environmental and infectious agents as well as immune deficiency states. We describe a case of primary non-Hodgkin's lymphoma of the parotid gland arising in the background of previously undiagnosed and untreated Sjögren's syndrome in a 52-year-old woman. The article concerns a short review of the literature regarding etiology, symptoms, treatment and survival prognosis in that rare disease as well. MALT lymphomas should always be considered in the differential diagnosis of the tumors and swelling of the parotid gland area. A special, regular monitoring should include all patients with Sjögren's syndrome as those with the proven greater risk of developing that proliferative disease. The role of the laryngologist in the case of MALT-type lymphoma of the parotid gland should focus on a diagnosis and possible tumor cytoreduction with maximal saving of the facial nerve. The essential treatment of this pathology is one of the oncologists and haematologists.

Stenoses of the salivary ducts-sialendoscopy based diagnosis and treatment.

Our aim was to analyse the nature of a sialendoscopy-based classification and present its use in the treatment of stenoses of Wharton's and Stensen's ducts. The classification of stenoses of Wharton's duct has not been published before. We did 133 sialendoscopies in 114 patients who presented with possible obstruction of the ducts to the tertiary centre for ENT at the University Department in Poznan. Twenty-seven patients had their parotid ducts treated, and 24 their submandibular ducts. Suspicion of stenotic changes of the ductal system was suggested during ultrasound examination. They were examined with semirigid endoscopes that enabled direct visualisation of the stenotic areas. A total of 69 stenoses were diagnosed in 51 patients. Stenoses were divided into three groups according to their site. Patients with stenosis of the salivary ducts were treated by dilatation of the stenotic area, intraductal steroid injections, and insertion of a stent for 14-21 days. Forty of the 51 reported considerable improvement, and 7 partial improvement. Four patients had no improvement. Sialendoscopy is a safe way to treat obstruction of the salivary glands. Short and medium term follow up show that it is extremely successful.

PRAME expression in head and neck cancer correlates with markers of poor prognosis and might help in selecting candidates for retinoid chemoprevention in pre-malignant lesions.

OBJECTIVES: PRAME (Preferentially Expressed Antigen in Melanoma) is a tumor-associated antigen recognized by immunocytes, and it induces cytotoxic T cell-mediated responses in melanoma. PRAME expression in tumors interferes with retinoic acid receptor (RAR) signaling thus promoting tumor progression. Here, we study PRAME expression in head and neck squamous cell carcinoma (HNSCC) to determine its potential clinical significance. MATERIALS AND METHODS: PRAME expression in HNSCC was evaluated by immunohistochemistry in tissue microarrays of primary tumors (n=53), metastatic lymph nodes (n=8) and normal oral mucosa (n=11). Biopsies of dysplastic oral lesions (n=12) were also examined. PRAME expression levels in tissues were correlated with markers of poor prognosis in HNSCC. PRAME mRNA in HNSCC cell lines and in normal immortalized human keratinocytes (HaCaT cell line) was measured by qRT-PCR, and the protein expression by flow cytometry and western blots. RESULTS: PRAME was expressed in HNSCC cell lines and HNSCC lesions. PRAME expression in dysplastic mucosa was variable. No or only weak expression was found in normal cells or tissues. PRAME expression levels significantly correlated with the tumor grade, size, nodal involvement and the clinical status of HNSCC patients. CONCLUSIONS: Elevated PRAME expression associates with clinicopathologic markers of poor outcome in HNSCC and might identify potential candidates with pre-cancerous lesions for chemoprevention with retinoids.

Sialoendoscopy and combined approach for the management of salivary gland stones.

UNLABELLED: The introduction of minimally invasive surgical procedures has significantly reduced the rate of major salivary gland removal due to sialolithiasis. The aim of this study is to assess the effectiveness of sialoendoscopy, rate of salivary fistula or natural ostium stenosis in parotid sialolithiasis treatment. The endpoint was to analyse the efficiency of a combined transcutaneous and endoscopic approach in the removal of refractory and impacted stones in most difficult cases. STUDY DESIGN: prospective study, tertiary university centre, between XII 2008 and XI 2011, 185 sialendoscopies (SE) were performed in 162 patients. Within the group of 29 patients with parotid sialolithiasis endoscopy was the definite treatment in 15 cases (53 %), in 9 cases lithotripsy (ESWL) was necessary and in 5 patients who failed SE and lithotripsy, a combined approach was performed. This approach comprised both SE and open surgery. We observed no salivary fistula formation after the incision of the duct. Stenosis of the natural ostium thanks to the insertion of stent was observed only in one case. Sialoendoscopy is the method of choice with a high rate of success and gland preservation in small and medium stones. The combined transcutaneous and endoscopic approach is indicated for large stones, for complications after and contraindications in using minimally invasive procedures. Short and medium term follow up shows that surgery can be performed with a high rate of success.

Is sonoelastography a helpful method for evaluation of parotid tumors?

Sonoelastography is a novel technique, useful in a noninvasive assessment of lesions in multiple organs. The aim of the study was to examine whether the combination of conventional ultrasonography (US) with sonoelastography might improve the reliability of parotid tumor evaluation. Fourty-three consecutive patients with parotid tumors were surgically treated at a single tertiary center at the Department of Otolaryngology, Head and Neck Surgery. The sample included 27 women and 16 men, aged 15-80 (the mean age = 54 years). The reference group constituted of 54 healthy volunteers. High resolution grayscale ultrasonography (US) was performed preoperatively using a 15 MHz linear array transducer. Elastograms (ES) were scored by the conventional Ueno 5-point scale from ES1 (blue-soft) to ES5 (the entire lesion and surrounding area shaded red-stiff). In addition, detailed stiffness values in kPa were collected. The group consisted of 33 patients with benign and 10 patients with malignant tumors. The mean stiffness value was 146.6 kPa in 10 malignant tumors (mostly ES4) and 88.7 kPa in 33 benign tumors (mostly ES2 and ES3). The differences in tissue stiffness between normal parotid parenchyma in the reference group and the mean value for all tumors in the examined group were statistically significant (p < 0.001), and so was the case with the differences between the benign and malignant tumors (p < 0.001). Low stiffness scores (ES1,2) were found in 2 malignant and 15 benign tumors while high scores (ES3,4) were found in 8 malignancies and 18 benign tumors. Sonoelastography overlapping elasticity to the grayscale images supports additional informations. Preferential selection of the lesions characterized by high stiffness (ES4) improves the differential diagnosis of parotid tumors but the large degree of uncertainty of this method should also be pointed out.

[Analysis of recurrence and treatment results of parotid gland non-malignant tumors with particular focus on pleomorphic adenoma]. / Analiza wystepowania i leczenia wznów guzów niezlosliwych slinianki przyusznej ze szczególnym uwzglednieniem gruczolaka wielopostaciowego.

UNLABELLED: The aim of the study was to assess the correlation between non-malignant parotid gland tumors recurrence and patient related parameters (age, gender, duration of complaints), type of tumor (histological pattern, the tumor diameter, primary localization in superficial or a deep lobe) and the treatment methods. The endpoint of the analysis was to come up with the presentation of the treatment methods applied to pleomorphic adenoma. MATERIAL AND METHODS: between 1997 and 2006, 675 patients with non-malignant tumors of parotid gland were treated in a single institution, the tertiary center for ENT at the University Department in Poznan. In the case of 249 patients--extracapsullar dissection was the adopted method of treatment, while in the case of the remaining 426 patients--lateral parotidectomy was performed. RESULTS: recurrence of tumor was diagnosed in 24 cases: 16 patients were found to have tumor with pleomorphic adenoma, 5--with cystadenolymphoma, 1--with onkocytoma, 1--with lipoma and 2--with monomorphic adenoma. Recurrence most often occurred inter-related with the two most common types of tumors: pleomorhic adenoma in 5% of the cases (12 out of 237) and cystadenolymphoma in 2.9% of the cases (12 out of 414). This inter-relation is, however, of negligible statistical significance (p=0.175). Yet, the multifactor analysis confirmed, that in case of pleomorhic adenoma, the duration of complaints for more than 3 years (p=0.001) and any previous extracapsullar dissection procedure (p=0.016) applied at the removal of the tumor did exert statistically significant impact upon recurrence. Tumor removal via extracapsullar dissection turned out to pose almost a 4 time greater risk of recurrence as compared to the lateral parotidectomy method.