[Histopathological grading and clinical features of patients with mucoepidermoid carcinoma of the salivary glands].
ABSTRACT In the 22 years between March 1979 and February 2001, we treated 16 patients--10 men and 6 women aged 10-80 years (mean: 44 years)--with mucoepidermoid carcinoma (MEC) of the salivary gland, evaluating them clinically and histopathologically. Tumor sites included 12 at the parotid gland, 3 at the submandibular gland, and 1 at the minor salivary gland. All tumors were graded histopathologically based on the criteria of Goode et al. as follows: low grade (n = 10), intermediate grade (n = 1), and high grade (n = 5). Female gender was associated with low grade MEC and male gender with high grade MEC (P < 0.05). The age at onset in high grade MEC was older than that in low grade MEC (P < 0.005). Lymph-node metastasis was detected in 7 out of the 16 patients (44%) associated significantly with high grade MEC (P < 0.05). Distant metastasis was detected in 4 of 16 patients (25%). Distant metastasis was significantly associated with high grade MEC (P < 0.05). Local recurrence was detected in 3 of 15 patients undergoing surgery (20%). No difference was seen in local recurrence frequency between low and high grade MEC. Survival was calculated with Kaplan-Meier's method. In all 16, 5-year survival was 86% and 10-year survival 75%. Five-year survival in low grade MEC was 100%, whereas that in high grade MEC was 67% (P < 0.05). In MEC of the salivary gland, it was suggested that the histopathological MEC grade evaluated by Goode's criteria significantly correlated with gender, age, lymph-node metastasis, distant metastasis, and 5-year survival.
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ABSTRACT: BACKGROUND: Mucoepidermoid carcinoma (MEC) can be classified into low-, intermediate-, and high-grade tumors based on its histological features. MEC is mainly composed of three cell types (squamous or epidermoid, mucous and intermediate cells), which correlates with the histological grade and reflects its clinical behavior. Most cancers exhibit reduced methylation of repetitive sequences such as Long INterspersed Element-1 (LINE-1) and Alu elements. However, to date very little information is available on the LINE-1 and Alu methylation status in MEC. The aim of this study was to investigate LINE-1 and Alu element methylation in MEC and compare if key differences in the methylation status exist between the three different cell types, and adjacent normal salivary gland cells, to see if this may reflect the histological grade. METHODS: LINE-1 and Alu element methylation of 24 MEC, and 14 normal salivary gland tissues were compared using Combine Bisulfite Restriction Analysis (COBRA). Furthermore, the three different cell types from MEC samples were isolated for enrichment by laser capture microdissection (LCM), essentially to see if COBRA was likely to increase the predictive value of LINE-1 and Alu element methylation. RESULTS: LINE-1 and Alu element methylation levels were significantly different (p<0.001) between the cell types, and showed a stepwise decrease from the adjacent normal salivary gland to the intermediate, mucous and squamous cells. The reduced methylation levels of LINE-1 were correlated with a poorer histological grade. In addition, MEC tissue showed a significantly lower level of LINE-1 and Alu element methylation overall compared to normal salivary gland tissue (p<0.001). CONCLUSIONS: Our findings suggest that LINE-1 methylation differed among histological grade mucoepidermoid carcinoma. Hence, this epigenetic event may hold value for MEC diagnosis and prognostic prediction.BMC Clinical Pathology 03/2013; 13(1):10. DOI:10.1186/1472-6890-13-10
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ABSTRACT: Mucoepidermoid carcinoma (MEC) and adenoid cystic carcinoma (ACC) are salivary gland neoplasms with divergent morphological features and clinical behavior. ACC is a basaloid tumor whereas MEC is a glandular epithelial neoplasm. FHIT and WWOX are tumor suppressor genes that encompass the FRA3B and FRA16D fragile sites at chromosomes 3p14.2 and 16q23.3, respectively. In previous studies, we have shown concordant loss of Fhit and Wwox expression in breast cancer, with significantly more frequent loss in cancers of basal-like phenotype. To determine if there is a similar association in salivary gland neoplasms, we designed a study of MEC and ACC of salivary gland on tissue microarrays (TMA). TMAs were constructed from 25 MEC and 19 ACC of salivary gland. Fhit and Wwox protein expression was assessed by immunohistochemical staining of cores on TMAs. Correlations among immunohistochemical markers and histological type were determined by statistical analyses. Significantly reduced Fhit and Wwox expression was observed in ACC (p=0.002 and p<0.001, respectively). The results suggest that, as for breast cancer, loss of Fhit and Wwox expression might have a role in the pathogenesis of basaloid differentiation in salivary gland neoplasms; alternatively, differences in chromatin structure at chromosome fragile regions might make fragile genes more accessible to DNA damage and rearrangement early during preneoplastic stages of basaloid cancers. Studies of basaloid tumors of other organ systems may show similar results and these findings may have implications for treatment modalities designed for basal-like tumors.Oral Oncology 03/2010; 46(3):195-9. DOI:10.1016/j.oraloncology.2009.12.003 · 3.03 Impact Factor
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ABSTRACT: Mucoepidermoid carcinoma (MEC) is the most common malignant tumor of salivary glands with a widely diverse biologic behavior that is correlated with the histological grade of the tumor. The purpose of this study was to evaluate the clinical outcomes of MEC of minor salivary glands in a group of 16 patients, who were treated in our clinic, and to discuss the management of this carcinoma. Between 1985 and 2000, 16 patients with MEC of minor salivary glands were treated in the Clinic of Oral and Maxillofacial Surgery of the 'G. Papanikolaou' General Hospital, in Thessaloniki. The age range was 16-65 years. The distribution of the primary sites was: hard plate (one), soft palate (two), hard and soft palate (three), hard and soft palate with spread in paranasal sinus and nasal cavity (one), buccal mucosa (three), hard palate, alveolar process and buccal mucosa (two), and retromolar triangle (our). The tumors were clinically staged according to the tumor nodes metastase (TNM) system (Seifert, 1991). All patients were treated radically with surgery. The surgery was combined with radiotherapy in nine patients. Radiotherapy was delivered using Co-60. Doses ranged from 50 to 60 Gy and the duration of the therapy ranged from 25 to 35 days. Immunohistochemical assay of the expression of the Ki-67 antigen was performed on a subset of 15 cases. The mean follow-up range was 4-14 years. From the 16 patients with MECs 10 (62.5%) were alive and five (35.6%) had died from the disease. Four patients were free of the disease for more than 5 years (range 8-14), five patients were free of the disease for 5 years and one patient was free of the disease for 4 years. One patient lived more than 10 years and died from another cause. Local recurrence developed in one patient 10 years after the initial treatment. Lymph node metastases occurred in one patient within the first year after the initial surgical treatment. Distant metastases (two in bones and one in lungs) occurred in three patients within 2 years after completing the treatment. The Pearson chi-square statistical analysis was used for comparing the Ki-67 values in correlation with histological grade of the tumors. The Ki-67 expression was only 1% in low-grade MECs, while in intermediate-grade tumors it was estimated between 3 and 4%. The high-grade tumors had increased expression (10%) of tumor cells. Complete surgical excision is the treatment of choice for MECs. Adequate excision is important in all grades of tumors. Prognosis of MECs is a function of the histological grade, adequacy of excision and clinical staging. The immunohistochemical study of Ki-67 expression may provide additional prognostic information for this tumor.Oral Diseases 08/2006; 12(4):364-70. DOI:10.1111/j.1601-0825.2005.01166.x · 2.40 Impact Factor