PubMed Health⌕ Search

Biomedical subjects

E Vairaktaris

Publications and source records attributed to E Vairaktaris.

At least 19 recordsLinked to original sources

[Solitary fibrous tumor in the tongue: case report and review of the literature].

Solitary fibrous tumors (SFT) are rare, mostly fibroblastic tumors usually situated in the pleura. Extrapleural manifestations have been described. However, the oral cavity is an uncommon localisation of this tumor. We report the very unusual case of an SFT affecting the tongue that could be removed completely because of its clear delineation. Intraoperative incisional biopsies were used to exclude malignancy. For definitive classification of the tumor, additional histopathologic examinations had to be carried out. Because SFT exhibit malignant behavior only in exceptional cases and their recurrence after complete removal has never been encountered, surgery can focus on the preservation of undisturbed function of the tongue.

Fibroma↗

The interleukin-8 (-251A/T) polymorphism is associated with increased risk for oral squamous cell carcinoma.

AIMS: In light of recently found contribution of angiogenic and inflammation-related factors to malignancies, this study investigated the possible association of interleukin-8 gene (IL-8) to increased risk of oral cancer. METHODS: The IL-8 (-251 A/T) polymorphism, which influences IL-8 gene expression, was evaluated by restriction fragment length polymorphism analysis in DNA samples of 158 German and Greek patients with oral squamous cell carcinoma and 156 healthy controls of equivalent sex, ethnicity and age. RESULTS: Significant increase of mutant (A-251) allele, which results in higher IL-8 gene expression, was observed in all patients in comparison to normal controls (P<0.001). The A/T heterozygotes had a two-fold greater risk (odds ratio 1.76, CI 1.11-2.79) for developing oral cancer compared to normal TT homozygotes. Furthermore, significantly increased values of mutant allele frequencies compared to controls were observed in all patients as well as in subgroups of patients with or without positive history of cancer (P<0.05 and P<0.001, respectively) and with or without positive history of thrombophilia (P<0.05 and P<0.001, respectively). CONCLUSIONS: In light to known observations of elevated plasma levels of IL-8 in several types of cancer including oral squamous cell carcinoma, the findings of this study suggest that the mutant allele of the (-251 A/T) polymorphism may be a major contributing genetic factor to risk for oral cancer.

Adult↗

Diabetes may increase risk for oral cancer through the insulin receptor substrate-1 and focal adhesion kinase pathway.

In light of recent epidemiological studies that associate diabetes mellitus with increased risk for oral cancer, we investigated in diabetic (type I) and normal rats with induced oral squamous cell carcinoma whether the molecular basis for that putative association involves insulin receptor substrate-1 (IRS-1) and focal adhesion kinase (FAK). Fourteen diabetic and 12 normal rats developed cancer after 4-nitroquinoline-N-oxide treatment, while six diabetic and six normal animals were used as controls. Oral sections were studied using monoclonal antibodies against IRS-1 and FAK proteins. Expression of IRS-1 was significantly higher in diabetic than normal rats, but it decreased in diabetic animals with tumor, especially in more advanced stages. FAK expression was significantly higher in rats with cancer in comparison to the ones without it, regardless the diabetes status. These data suggest that the IRS-1/FAK pathway is altered by diabetes resulting in reduced cell adhesion and possibly increasing risk for oral cancer.

Animals↗

Plasminogen activator inhibitor-1 polymorphism is associated with increased risk for oral cancer.

In light of the recently observed contribution of thrombosis-related factors to carcinogenesis, we investigated the possible association of plasminogen activator inhibitor-1 (PAI-1) with increased risk for oral cancer. In DNA samples of 104 patients with oral squamous cell carcinoma and 106 healthy controls of comparable ethnicity, age and sex, we studied the 4G/5G polymorphism in the PAI-1 gene, which affects its expression. The mutant 4G allele and carrier frequencies were significantly increased in patients compared to controls (65.9% versus 49.5%; 88.5% versus 69.8% respectively, P<0.01). That increase was even higher in patients with a positive family history for thrombophilia or without one for cancer (P<0.001). Interestingly, significant difference from controls was observed only in patients with cancer stages I and II. These findings suggest that the 4G allele, by resulting in higher PAI-1 expression, is a major contributing factor in early stages of oral oncogenesis. Possibly, increased PAI-1 promotes initial development of oral cancer through regulation of cell detachment and delays further tumor progression by inhibiting vascularization.

Adult↗

Association of platelet glycoprotein Ia polymorphism with minor increase of risk for oral cancer.

AIMS: In light to association of increased platelet glycoprotein Ia (GPIa) expression with tumor invasion and metastasis in several types of cancer, we investigated the possible contribution of a common polymorphism (C807/T807), affecting the GPIa gene expression, in the development of oral cancer. METHODS: DNA samples of 110 patients with oral cancer and 114 healthy controls were examined by allele-specific polymerase chain reaction followed by electrophoretic analysis. RESULTS: The mutant T807 allele homozygotes were significantly increased in the group of patients compared to the control group (P < 0.001). Furthermore, significantly increased frequency of mutant alleles compared to controls was observed in the subgroup of patients with a positive history for cancer (P < 0.01). CONCLUSIONS: The obtained results indicate that the C807/T807 polymorphism is indeed a genetic predisposing factor which contributes to increased risk for oral cancer.

Alleles↗

Cell proliferation and apoptosis culminate in early stages of oral oncogenesis.

Markers of cell proliferation (Ki-67 antigen) and apoptosis (Bax, Bcl-2) were studied in an experimental system of induced oral carcinogenesis in Syrian golden hamsters. Thirty-seven animals were divided into one control group and three experimental groups, which were treated with a carcinogen and sacrificed at 10, 14 and 19 weeks after treatment. The histological status of the lesions in the three experimental groups corresponded well with tumour advancement (from oral mucosal dysplasia to moderately differentiated squamous cell carcinoma). Tumour sections were studied using monoclonal antibodies against Bax, Bcl-2 and Ki-67 proteins. Pro-apoptotic Bax expression maintained high levels during all stages of oral carcinogenesis. Anti-apoptotic Bcl-2 expression decreased significantly in dysplastic and early invasion lesions and consequently increased almost to normal tissue level in consequent stages. Finally, Ki-67 expression increased sharply in initial stages of oral carcinogenesis, but significantly decreased in later stages.

Animals↗

Methylenetetrahydrofolate reductase polymorphism and minor increase of risk for oral cancer.

PURPOSE: We investigated whether the mutant methylenetetrahydrofolate reductase (MTHFR) increases risk for oral cancer. The common germ-line mutation C677T in the MTHFR gene significantly diminishes specific activity of the enzyme, which is responsible for the circulating form of folate. Folate deficiency is associated with increased risk for thrombosis, as well as for several types of cancer, through disruption of DNA methylation, DNA synthesis and deficient DNA repair. METHODS: We searched for the C677T mutation by restriction fragment analysis of PCR products in DNA samples of 110 patients with oral squamous cell carcinoma and 120 healthy controls of comparable ethnicity, age and sex. RESULTS: The number of heterozygotes was significantly different in the two groups (P<0.005), as well as in subgroups of patients with or without a positive family history for cancer, compared to normal controls (P<0.01 and P<0.005, respectively). Furthermore, the subgroup of patients with a positive family history for thrombophilia had a significant increase both in the frequencies of mutant alleles (P<0.01) and heterozygotes (P<0.001) in comparison to normal controls. CONCLUSIONS: The obtained results suggest that the MTHFR mutation is a minor contributing factor in oncogenesis in the oral region, in conjunction with low dietary uptake of folate.

Adult↗

Blood supply to the oral and maxillofacial tissues following radiation therapy: a prospective ultrasonographic study.

In this prospective clinical study of the early radiation effects on blood supply to the mouth and face, 44 patients (31 men-13 women, mean age 63.4 yrs) with oral tumors underwent surgery and adjuvant postoperative radiotherapy with conventional fractionation (mean dose at the neck approximately equal to 50 Gy). Blood flow parameters 1 cm below the bifurcation of the common carotid artery (mean velocity time averaged, lumen diameter, resistivity index-RI) as well as perivascular reaction, were recorded on Color Doppler Imaging video tapes in a series of five consecutive examinations up to six months postirradiation. There were no statistically significant changes shown between the initial and follow-up examinations for any of the parameters investigated. There was no difference in blood flow between the ipsilateral (operated-irradiated) and contralateral side of the neck. Results did not seem to correlate with known vascular disease risk factors such as sex, arterial pressure, cholesterol levels, smoking and diabetes. After the effect of age was controlled, flow measurements remained statistically stable. Radiation dosage did not appear to influence carotid flow parameters. Perivascular reaction had the highest peak immediately postirradiation but regressed with time. This study suggests that therapeutic radiation of the neck at this dose level may not have important effects on the maxillofacial region blood supply for approximately eight months postoperatively; however, these patients should be closely evaluated for symptoms or signs of carotid artery lesions on a long-term basis.

Adenocarcinoma↗

Lingual thyroid: a new surgical approach--a case report.

Ectopic lingual thyroid is a rare developmental anomaly, presenting in the adult with obstructive symptoms during respiration, deglutition and speech. The main therapeutic issue after exact diagnosis is the restoration of thyroid function, and surgical intervention, when necessary, has to deal with problems related to the site and function of the ectopic gland. A case of a 25-year-old female with dyspnoea and dysphagia due to a 3 x 4 cm ectopic lingual thyroid, excised by an original peroral approach via a mandibular midline osteotomy, is reported. Our surgical technique is described and the diagnostic and therapeutic problems are reviewed.

Adult↗

Mycobacterial cervical lymphadenitis. A clinicopathological study of 3 cases.

Three adult patients with tuberculous cervical (submandibular) lymphadenitis were treated in the past year in the Department of Oral and Maxillofacial Surgery, Evangelismos Hospital, University of Athens. None had a history of exposure to tuberculosis. In all, the chest X-rays were clear but the PPD tests were positive. All patients underwent excisional biopsy of grossly involved lymph nodes and histological examination and special stains confirmed the diagnosis. The patients were subsequently treated with triple drug administration. Antituberculosis chemotherapy consisted of isoniazid, rifampin and ethambutol and all are well after a follow-up of 9, 10 and 11 months respectively. Medical approaches often failed to diagnose tuberculous cervical lymphadenitis conclusively, and this disease remains a diagnostic and therapeutic challenge, because it mimics other pathological processes. The treatment of choice seems to be surgical excision and long term antituberculosis chemotherapy. Surgery provides a rapid tissue diagnosis, because the histological examination of the excisional biopsy is the most reliable diagnostic test.

Aged↗

[Laryngeal insufficiency as a post-traumatic complication of facial skull injury].

Laryngeal incompetence is characterised by incoordination in deglutition and fluid leakage around the tracheostomy tube. It occurs very rarely and is attributed to injury of the recurrent laryngeal nerve. To our experience this condition demands no treatment and gradually disappears. In this paper we present a case of a 24-year-old male patient with facial fractures presenting laryngeal incompetence.

Adult↗

[Indications for tracheostomy in patients with oral and maxillofacial problems].

Tracheostomy encounters in several conditions in oral and maxillofacial surgery. Upper airway obstruction is the most common, often occurring secondary to maxillofacial trauma. Obstruction may also be caused by neoplasms of the oral cavity, by hematoma, oedema, abscess or allergy. In this paper we discuss the indications for tracheostomy in patients with oral and maxillofacial problems and the complications that may occur in patients from the procedure itself.

Airway Obstruction↗

[Primary melanoma of the oral cavity].

Melanoma most often develops in the skin; usually at the site of a preexisting nevus. It is quite rare in the oral cavity and the maxilla is the most common location there. It appears that males between 60 and 70 years old are affected more often than females. The etiology is unknown. However the melachromatic nevus and the color of the skin are considered predisposing factors. Based on clinical and histologic criteria it is classified in three categories. Unfortunately the frequency of the occurrence of each category into the mouth separately, is inversely proportional to the prognosis. The 5 year survival rate of intraoral melanoma does not exceed 5-9%. The treatment of melanoma is surgical and comprises radical excision of the lesion and radical neck dissection. Radiotherapy and chemotherapy do not seem to contribute to the treatment. We present our experience of two patients with melanoma of the maxilla. In one case submandibular lymphadenopathy had already been established and a radical neck dissection was performed. In the other case subtotal maxillectomy was performed with intraoral approach.

Female↗