Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Sefa Kaya is active.

Publication


Featured researches published by Sefa Kaya.


International Journal of Pediatric Otorhinolaryngology | 2000

Melanotic neuroectodermal tumor of infancy: report of two cases and review of literature.

Sefa Kaya; Ömer Faruk Ünal; Sarp Sarac; Gokhan Gedikoglu

Melanotic neuroectodermal tumor of infancy (MNTI) is a rare, distinctive neoplasm containing melanin; it primarily affects the maxilla of the infants during the first year of life. Approximately 150 instances of this tumor are reported in the medical literature. Genesis of the tumor is obscure and the diagnosis is challenging for the pathologist. Two cases operated by the first author are presented, and the diagnostic features and treatment alternatives of MNTI discussed.


Laryngoscope | 2001

Benign paroxysmal positional vertigo after stapedectomy.

Erbil Atacan; Levent Sennaroglu; Aydan Genç; Sefa Kaya

Objective To determine the incidence of benign paroxysmal positional vertigo (BPPV) following stapedectomy in a patient group and the efficacy of the Epley maneuver in this group.


Laryngoscope | 2002

The Effects of Tonsillectomy and Adenoidectomy on Serum IGF-I and IGFBP3 Levels in Children

Mustafa Deniz Ylmaz; A. Sefik Hosal; Havva Oğuz; Nursen Yordam; Sefa Kaya

Objective Obstructive adenoid and tonsillar hyperplasia may present with retardation of growth. Interruption of growth hormone‐insulin‐like growth factor I axis resulting from abnormal nocturnal growth hormone secretion is among the postulated causes. Growth hormone (GH) mediates its anabolic effects on tissues through insulin‐like growth factor I (IGF‐I). Most of the circulating IGF‐I is bound to insulin‐like growth factor binding protein 3 (IGFBP3). The objective of this study is to determine blood serum levels of IGF‐I and IGFBP3 in patients with adenoid and tonsillar hypertrophy. Furthermore, we want to investigate the effect of tonsillectomy and adenoidectomy (T&A) on these levels.


European Archives of Oto-rhino-laryngology | 1999

Prognostic significance of histopathological parameters in cancer of the larynx

Taner Yılmaz; A. Ş. Hoşal; Gokhan Gedikoglu; Sefa Kaya

Abstract In this study we investigated the prognostic significance of differentiation, the mode of tumor invasion to surrounding tissues, the microscopic appearance of tumor, peritumoral lymphocytic infiltration and cartilage involvement according to disease-free survival, and the recurrence and presence of cervical lymph node metastasis in cancer of the larynx. Only the mode of tumor invasion to surrounding tissues was significantly related to survival (P < 0.05). The patients with “well-defined margin” tumors survive significantly longer than those with “groups of cells, no distinct margin.” Patients with supraglottic tumors and a mode of invasion other than “well-defined margin” have a significantly higher risk of recurrence (P < 0.05) and therefore require adjuvant therapy. Patients with poorly differentiated, cartilage invading, ulcerative supraglottic tumors, and patients with glottic tumors having diffusely infiltrating margins, certainly need elective neck dissection (P < 0.05). According to the multivariant analysis, none of the factors significantly affect disease-free survival independently (P > 0.15). According to multiple logistic regression and cox regression analysis, in decreasing order of significance, the mode of invasion, microscopic tumor appearance and lymphocytic infiltration significantly affect the recurrence and time between surgery and the development of recurrence independently (P < 0.15).


American Journal of Otolaryngology | 1992

Squamous cell carcinoma of the lower lip

I.Nazmi Hosal; Metin Önerci; Sefa Kaya; Ergin Turan

PURPOSE Most patients with squamous cell carcinoma of the lower lip present with early disease and follow a rather indolent clinical course. Determinant 5-year survival rates range from 85% to 95%. This study was undertaken in an attempt to gain insight into the cause of failure in those few patients who develop recurrent disease. PATIENTS AND METHODS A retrospective review was completed on patients treated between 1964 and 1990. Patients were staged according to the American Joint Committee. Patients with no palpable adenopathy had either a unilateral or bilateral suprahyoid dissection performed. Patients with palpable adenopathy underwent radical neck dissection. All patients were followed for evidence of recurrent disease. RESULTS The records of 92 patients treated surgically for squamous cell carcinoma of the lower lip were available and complete. Palpable adenopathy was present in 38 patients; however, only 8 of these patients (21%) were histologically positive. Of the 54 patients judged to be free of disease, 3 (5.5%) had histologic evidence of metastasis. Overall, the incidence of cervical metastasis was 12%. CONCLUSION The incidence of cervical metastasis in patients with squamous cell carcinoma of the lip is low; however, these data suggest that the size of the primary tumor does not correlate closely with predicting the incidence of regional lymph node metastases.


Pediatric Neurology | 1994

Lymphoma with bilateral cavernous sinus involvement in early childhood

Mehmet Ceyhan; Güliz Erdem; Kanra G; Sefa Kaya; Metin Önerci

A 4-year-old girl developed complete ophthalmoplegia with intact pupillary responses. Computed tomography and magnetic resonance imaging demonstrated a mass invading the cavernous and sphenoid sinuses and posterior ethmoidal cells. Biopsy revealed non-Hodgkin lymphoma. This patient is the youngest reported with malignant lymphoma of the cavernous sinus and the second reported with bilateral cavernous sinus involvement.


Otolaryngology-Head and Neck Surgery | 2004

C-Met Overexpression in Supraglottic Laryngeal Squamous Cell Carcinoma and its Relation to Lymph Node Metastases:

Yücel Ö Taskin; Arzu Sungur; Sefa Kaya

BACKGROUND: The c-met oncogene encodes the receptor for the hepatocyte growth factor/scatter factor (HGF/SF), which is known to have the effects of stimulation of cell motility, dissociation of epithelial sheets, invasion of cellular matrix, and induction of angiogenesis. Many studies in solid tumors have indicated a role for c-met and HGF/SF in the progression of the disease. METHODS: The expression of c-met in tissue specimens was studied by immunohistochemical examination in 60 patients with supraglottic laryngeal squamous cell carcinoma. Patients were chosen such that there were 30 with lymph node metastases in the neck and 30 without metastases. TNM staging, differentiation, lymphovascular and perineural invasion, and growth pattern for tumors were also recorded, and their relation to lymph node metastases was analyzed. RESULTS: Overexpression of c-met was observed in 90% of the cases at the primary site and in 83% of the cases with lymph node metastases in the neck. Lymphovascular invasion (P = 0.005) and the N stage (P = 0.001) were found to be related to lymph node metastases, but other variables—c-met over-expression, the T stage, perineural invasion, and growth pattern—were found to have no relation to lymph node metastases in multivariate analysis of the data with linear regression. CONCLUSIONS: c-met overexpression is observed in both the primary site and the neck in supraglottic laryngeal squamous cell carcinoma. We believe that it may have a role in the progression of malignancy, but we were unable to find a definite relation between c-met expression and lymph node metastases. (Otolaryngol Head Neck Surg 2004;130:698-703.)


International Journal of Pediatric Otorhinolaryngology | 1998

Sinus histiocytosis with massive lymphadenopathy (Rosai–Dorfman disease)

Ömer Faruk Ünal; Serap Köybaşı; Sefa Kaya

Sinus histiocytosis with massive lymphadenopathy (SHML) is a distinct clinicopathological entity described by Rosai and Dorfman and differentiated by other childhood histiocytoses by its distinct characteristics. This is a rare pathology and should be kept in mind for differential diagnosis of neck masses, especially in childhood. In this article a case with SHML is presented and clinical features of the disease given.


European Archives of Oto-rhino-laryngology | 2001

Positive surgical margins in cancer of the larynx

Taner Yılmaz; Ergin Turan; Bülent Gürsel; Metin Önerci; Sefa Kaya

Abstract In order to determine what should be done for laryngeal cancer patients when surgical margins are positive, and to evaluate their prognosis, a retrospective review of 21 laryngeal cancer patients with positive surgical margins out of 714 surgically treated cases (2.9%) was carried out. Nineteen patients were treated with postoperative radiation therapy. Two patients who had had endolaryngeal partial laryngectomy were treated with vertical partial laryngectomy. Two patients were lost to follow-up. Ten patients (10/19; 53%) were recurrence-free. Four patients had local, two had regional, and two had locoregional recurrences. Only one patient with a local recurrence could be salvaged with total laryngectomy and is disease-free. One patient developed liver metastasis. Nineteen patients had a mean and median disease-free survival of 48 and 36 months, respectively. Nine out of fourteen patients (64%) treated curatively were recurrence-free. The patients with positive margins developed significantly more locoregional recurrences than those with free margins (P < 0.05). We conclude that surgical margins must be checked peroperatively with frozen sections to make sure that they are free. The margins of every laryngectomy specimen must be diligently examined. If positive, re-excision, postoperative radiotherapy and chemotherapy are treatment alternatives. They should not just be managed with close follow-up. However, whatever treatment is applied, the prognosis for patients with positive margins is significantly worse than for those with free margins.


European Archives of Oto-rhino-laryngology | 1985

Measurement of tonsillar blood flow in normal and pathological conditions by the use of the 133Xe clearance technique.

Ismail Özdemir; Meral T. Ercan; Sefa Kaya

SummaryBy using the 133Xe clearance technique, we measured the blood flow to the human palatine tonsil in 10 normal volunteers, 11 patients with chronic tonsillitis, and 11 with hypertrophic tonsils. We found that the mean blood flow was 30.08 ± 5.39 ml/ 100 g per min in normal tonsils, 17.06 ± 3.72 in chronic tonsillitis and 49.50 ± 9.30 in hypertrophie tonsils. Our results show a statistically significant decrease in blood flow in chronic tonsillitis (P<0.01) and a significant increase in hypertrophic tonsils (P<0.01) when compared to the normal controls. The difference between the blood flow in chronic tonsillitis and hypertrophic tonsils was also statistically significant (P<0.01). In all three groups studied, no statistically significant difference was observed in the blood flow to the right and left tonsils (P<0.05).

Collaboration


Dive into the Sefa Kaya's collaboration.

Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge