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Biomedical subjects

Hakan Korkmaz

Publications and source records attributed to Hakan Korkmaz.

15 recordsLinked to original sources
PubMed2007

Pilot study of intraoperative chemotherapy with cisplatin and 5-fluorouracil in patients with advanced squamous cell carcinoma of the head and neck.

BACKGROUND: Intraoperative manipulation of the tumor during cancer surgery has long been recognized as a source of metastasis and contamination of the surgical wound during tumor removal. We explored the use of intraoperative chemotherapy to minimize the risk of tumor cell implantation and metastasis during head and neck cancer surgery and conducted a dose escalating intraoperative chemotherapy clinical trial designed to assess the feasibility of this approach and associated toxicities in patients with advanced squamous cell carcinoma of the head and neck. METHODS: Fourteen patients were treated with 5-fluorouracil at a dose of 1000 mg/m(2) administered intravenously over an 8-hour period during the surgery with simultaneous cisplatin. The cisplatin dose was escalated and toxicity observed. Cisplatin at 75 mg/m(2) was chosen as the maximum tolerated dose level. RESULTS: One patient experienced a grade 3 nephrotoxicity, 1 patient a grade 1 neuropathy, and 5 patients grade 2 nausea (36%). There were no grade 4 toxicities. CONCLUSION: Intraoperative chemotherapy is feasible, and the combination of cisplatin at 75 mg/m(2) and 5-fluorouracil at 1000 mg/m(2) can be administered during surgery without significant toxicity.

Aged↗
PubMed2004

Lipoid proteinosis of larynx: review of four cases.

Lipoid proteinosis is a rare autosomal recessive disorder characterized by intercellular deposition of an amorphous hyaline material. It mainly involves skin and mucosal membranes of upper aerodigestive tract as well as central nervous system, lung, lymph nodes and striated muscles. Etiology and pathogenesis are unknown. Infantile hoarseness is a common presenting feature of the disease due to infiltration of larynx. In two-thirds of the cases, voice changes are present at birth or in early infancy as the first manifestation. We present four patients with lipoid proteinosis involving skin, oropharynx and larynx.

Adolescent↗
PubMed2004

Correlation of histopathological variants, cellular DNA content, and clinical outcome in adenoid cystic carcinoma of the salivary glands.

OBJECTIVE: To study the correlation between flow cytometrically measured DNA ploidy with prognostically important histopathologic groups and clinical outcome in patients with adenoid cystic carcinoma of the salivary glands. STUDY DESIGN: 46 tumor specimens were analyzed flow cytometrically for DNA content and assessed for histological grade. Correlations were made between tumor DNA ploidy and histopathological grade, and disease-free and overall survival of these patients. RESULTS: Of the 46 patients, 31 had a cribiform/tubular histologic pattern, and 15 had a solid pattern. 84% of the tumors with cribriform/tubular pattern were DNA diploid, compared with 33% of tumors that were graded solid. This difference proved to be statistically significant (chi(2)11.75, P = 0.0006). Overall and disease-free survival periods were longer for patients with DNA diploid tumors in both groups, 63% vs. 36% and 62% vs 38%, respectively. CONCLUSIONS: Tumor DNA ploidy correlates with prognostically important tumor histopathology as well as overall and disease-free survival in patients with adenoid cystic carcinoma of the salivary gland. EBM RATING: B-3.

Adult↗
PubMed2004

Pseudoaneuploid subpopulations detected in normal upper aerodigestive tract mucosa consistent with physiological apoptosis in normally differentiating squamous mucosa.

OBJECTIVES: While evaluating the validity of using normal human mucosal cells from the upper aerodigestive tract as diploid standards for DNA content studies of squamous cell cancer of head and neck by flow cytometry, pseudoaneuploidy was frequently detected. The purpose of this study was to further evaluate these DNA content abnormalities encountered in normal human mucosal cells and correlate them to physiological apoptosis. STUDY DESIGN: Thirty-two specimens of upper areodigestive tract mucosa from 18 surgical resections, 11 fresh autopsies, and 3 buccal scrapings were examined for DNA content by flow cytometry. RESULTS: Pseudoaneuploidy, which ranged from sub-G0/G1 peaks to hyperdiploid peaks with increased 90 degrees light scattering properties was found in 60% of these specimens. Fluorescent microscopic examination of the sorted DNA pseudoaneuploid cells demonstrated cells undergoing apoptosis. CONCLUSION: This unexpected pseudoaneuploidy in normal mucosal cells was a result of physiological apoptosis, a normal component of squamous differentiation. EBM RATING: B-2.

Aneuploidy↗
PubMed2004

Role of free radicals and antioxidants in nasal polyps.

OBJECTIVES/HYPOTHESIS: The aim of this study is to determine the role of free radicals and antioxidants in nasal polyps. STUDY DESIGN: Prospective, randomized, controlled study. METHODS: Thirty-one patients with nasal polyposis and a control group consisting of 19 patients with septal deviation and lower turbinate hypertrophy were included in the study. Levels of the antioxidants retinol, beta-carotene, alpha-tocopherol, and ascorbic acid were measured from the sera of the patients with nasal polyposis and the control group. Plasma levels of superoxide dismutase activity (SOD), glutathione peroxidase (GSHPX) activity, and reduced glutathione (GSH) were also obtained. As a peroxidation product, the levels of the malondialdehyde-thiobarbituric acid (MDA) combination were measured from the plasma of patient and control groups. Measurements of MDA, GSH, and alpha-tocopherol levels were also taken from the polyp tissue and turbinate mucosa of the control group. RESULTS: The blood levels of antioxidants and MDA as an oxidant were significantly different in the patient group compared with the control group (P <.01). The tissue levels of antioxidants and MDA were significantly different in the patients with polyposis compared with the control group (P <.01). The blood and tissue anti-oxidant levels were found to be decreased, and MDA levels as an oxidant increased significantly in the patient group with polyposis when compared with the control group, and there was a negative correlation between oxidative stress and antioxidants. CONCLUSION: This study demonstrates that oxidative stress and tissue and blood antioxidants in the patients with polyposis were significantly different compared with the control group. The blood and tissue antioxidant levels decreased, and MDA levels, as an oxidant, increased significantly in the patient group with polyposis when compared with the control group. The current study demonstrates that there is strong evidence related to oxidative stress in the pathogenesis of nasal polyposis, and antioxidants can have a preventive role in free-radical-mediated tissue damage in nasal polyposis.

Adolescent↗
PubMed2004

Ultrastructural and electrophysiologic changes of rat cochlea after irradiation.

OBJECTIVE/HYPOTHESIS: To determine the acute and subacute cochlear effects of sublethal total body irradiation. STUDY DESIGN: The study was designed prospectively as a Sprague-Dawley (SD) rat model with otoacoustic emission measurement. METHODS AND MATERIALS: Ten rats and 20 ears were included in the study. Distortion product otoacoustic emission (DPOAE) measurements were performed under ketamine anesthesia before and 1 to 8 weeks after sublethal dose total body irradiation. Eight and six rats survived at the first and eighth week measurements, respectively. The frequency bandwidth was set to 1,067 Hz (referenced to f1) - 9,512 Hz (referenced to f2) (2f1 - f2 = 832 - 6,076 Hz) and eight points were sampled per octave, but low-frequency (<2,549 Hz [referenced to 2f1 - f2]) results were not included in the analysis. Averages were obtained at each frequency, and statistical analysis was performed to compare the pre-and postradiation values. Then, three of the rats were killed for transient electron microscopy (TEM) of the temporal bones. RESULTS: The posttreatment DPOAEs at almost all frequencies showed a trend toward decline at both the first and eighth weeks, but significant reduction was only detected at 3,600 and 3,961 Hz (referenced to 2f1 - f2) in the first week. TEM of the cochlea revealed ultrastructural changes in the outer hair cells (OHCs) and stria vascularis of the basal turn. The cochlear ganglion nuclei and cochlear nerve axons were unaffected. CONCLUSION: Radiation can affect the cochlea in the acute phase at the mid to high frequencies; further prediction for long-term effects requires longer follow-ups.

Animals↗
PubMed2004

The incidence of anatomic variations and sinus opacities in pediatric patients with chronic sinonasal symptoms.

OBJECTIVES: In this study, our purpose was to determine the incidence of paranasal sinus anatomic variations and their relationship with sinus opacities in pediatric patients. PATIENTS AND METHODS: A total of 44 children (age range 3 to 16 years) unresponsive to maximum medical therapy were evaluated with coronal paranasal sinus computed tomography. RESULTS: Computed tomographic evaluations revealed that 70.5% (31/44) of the patients had at least one anatomic variation, the most common being septal deviation, followed by concha bullosa and agger nasi cells. Sinus opacities were found in 81.8% (36/44) of the patients, of whom 9 had single and 27 had multiple involvement of sinus groups. The most commonly involved sinuses were anterior ethmoids and maxillary sinuses, followed by posterior ethmoids, sphenoid and frontal sinuses. Patients with single, multiple, and no anatomic variations had 78.9% (15/19), 83.3% (10/12), and 84.6% (11/13) opacities, respectively. CONCLUSION: The incidence of anatomic variations was found to be similar to that reported for adults in the literature except for nasal septal deformity which was found lower. Our results showed no correlation between bony anatomic variations and sinus opacities in children.

Adolescent↗
PubMed2003

The role of 70-degree telescopic examination during direct laryngoscopic evaluation of laryngeal cancers.

Endoscopy has currently been an indispensable method in many areas of otorhinolaryngology, especially in paranasal sinus surgery. Telescopic evaluation of the larynx has not drawn much attention. In this study, a 70-degree angled rigid telescope was used along with computerized tomography (CT), indirect and direct laryngoscopy in the evaluation of laryngeal cancer. The critical areas such as the anterior commissure, subglottic region and ventricles were investigated specifically. Nineteen patients were collected in the study. We found the sensitivity for indirect laryngoscopy to be 20-25% and for direct laryngoscopy to be 50-70%. The scores for CT and 70-degree telescopy were 70-100%. In the subglottic region telescopy was superior to CT. We believe that, when it is used in association with CT, telescopy provides better insight when deciding between partial or total laryngectomy and a healthier evaluation of the resection margin.

Adult↗
PubMed2003

Clinical predictors of long-term success after endoscopic sinus surgery.

OBJECTIVE: Determining the clinical predictors of long-term success after endoscopic sinus surgery (ESS) would better guide the management of patients. METHODS: One hundred-thirty chronic rhinosinusitis (CRS) patients were evaluated retrospectively. Overall subjective improvement was 83% with a mean follow-up of 60 months. Eighty percent had anatomic variations; 36.2%, allergy; 55.4%, nasal polyps; and 26.9%, history of previous operation. The improvement was 100%, 94%, 79.5%, and 69.7% in stages 0, I, II, and III, respectively. With other parameters, the success rates were 68.1% and 91.6% with and without allergy, 73.6% and 94.8% with and without polyps, 54.3% and 93.7% with and without previous history of surgery, 84.4% and 82.7% with and without anatomic variations, and 23.8% and 94.4% with and without recurrent polyps. CONCLUSION: In multivariate Cox regression analysis, allergy (P < 0.05; relative risk, 4.6) and previous polypectomy (P < 0.05; relative risk, 9.9) were found to be predictors of poor prognosis in the long-term follow-up.

Adolescent↗
PubMed2002

Predictors of nodal metastasis in salivary gland cancer.

OBJECTIVES: This study was conducted to determine clinical and histologic factors that would predict nodal metastasis in patients with major salivary gland cancer. METHODS: A retrospective study of 40 patients who underwent surgery, including neck dissection, for major salivary gland cancer between 1975 and 1997 was performed. Patient charts were reviewed, and clinical and pathologic data were extracted along with outcome. Predictive factors were identified and survival curves were obtained. RESULTS: Neck dissections were performed in 40 patients, which revealed histologic evidence of tumor in lymph nodes in 15 cases. Histologically proven metastasis was found in 16% of specimens from elective and 73% of specimens from therapeutic neck dissection. Five-year overall and locoregional disease-free survival rates for histologically positive and negative groups were 40% versus 63% (P < 0.05) and 67% versus 69% (P = 0.59), respectively. Univariate analysis of the factors revealed that clinical evidence of nodal metastasis (P < 0.001) and high-grade cancer (P < 0.033) predicted histologic nodal involvement. Multivariate analysis revealed that only a positive neck examination was a significant predictive factor (OR = 31, 95%CI = 2.99-312). CONCLUSIONS: Our results suggest that clinical neck examination is a reliable predictor of regional metastasis in patients with major salivary gland cancer. In view of the low frequency of occult metastases, routine elective treatment of the neck is not recommended.

Adolescent↗
PubMedDate not supplied

Prognostic significance of G1 cell-cycle inhibitors in early laryngeal cancer.

BACKGROUND: Radiation therapy yields a 2-year local control rate of 80% to 90% in early laryngeal squamous cell carcinoma. However, a subset of early laryngeal cancers has a significantly higher rate of local recurrence and lower rate of overall survival. OBJECTIVE: The objective of this study was determine the prognostic significance of p53, p27, and p21 expression in patients with early laryngeal cancer. METHODS: Expression of p53, p27, and p21 proteins in pretreatment biopsies from sixty-eight patients was analyzed by using immunohistochemistry. Low (</=10% cells) and high (>10% cells) levels of expression were measured. All patients were newly diagnosed and treated with external beam radiation. Other contributing factors were also studied, such as age, sex, race, tumor site, and stage. RESULTS: Forty (58.8%) and 28 (41.2%) lesions were staged as T1 and T2, respectively, whereas 16 (23.5%) and 52 (76.5%) were located in the supraglottis and glottis, respectively. Overexpression of p27, p53, and p21 was found in 36.7%, 60.6%, and 60% of cases, respectively. Overexpression of p27 was found to be a significant predictor of recurrence by multivariate analysis (RR 3.3, P = .017). Overexpression of p21 and/or p53 was not predictive of recurrence. No factor predicted disease specific or nonspecific overall survival. CONCLUSION: Our results indicate the significance of p27 overexpression as an indicator of recurrence in patients with early laryngeal squamous cell carcinoma.

Adult↗
PubMedDate not supplied

Is septoplasty alone adequate for the treatment of chronic rhinosinusitis with septal deviation?

BACKGROUND: The purpose of this study was to reveal the role of septoplasty in curing chronic rhinosinusitis (CRS) in patients with significant septal deviation. METHODS: This prospective study involved 26 patients with CRS and septal deviation. The patients were randomly divided into two groups according to the applied surgical procedures. In the first and second groups, septoplasty and septoplasty plus endoscopic sinus surgery were applied, respectively. Subjective (questionnaire) and objective (endoscopy and computerized tomography) success rates were used to analyze the results. RESULTS: Septoplasty alone and septoplasty plus endoscopic sinus surgery were applied in 57.7% (15/26) and 42.3% (11/ 26) of the patients, respectively. Success rates were 93.3% (14/15) and 81.8% (9/11), subjectively (p > 0.05), and 66.7% (10/15) and 54.5% (6/11), objectively (p > 0.05), respectively in each group. CONCLUSION: We suggest that septoplasty alone can be adequate for the treatment of CRS with septal deviation.

Adolescent↗