High-grade Mucoepidermoid Carcinoma Research Articles

P27/SKP-2 Histochemical Profile is Relevant to Malignant Salivary Gland Tumors (MST) Histogenesis and Tumor Grade

Malignant salivary gland tumors (MST) represent over more than 24 distinct morphological subtypes. Most high grade tumors arise from the excretory duct portion of the salivary gland apparatus; the remainder from the intercalated duct portion. Altered p27/skp-2 expression has been associated with tumor aggressiveness and histologic differentiation. In our study, we analyzed p27/skp-2 expression proteins on series of malignant salivary gland tumors in order to assess their value as a histogenetic marker, which is relevant to tumor grade. 61 MST cases were segregated by proposed histogenesis and immunohistochemistry was performed using antibodies directed against p27 and skp-2. MST of proposed intercalated duct origin (n=27) showed strong p27 expression (n=25/27; 93%) in the vast majority of cases and all cases weakly expressed skp-2. MST of proposed excretory duct origin (n=32) showed strong p27 expression (n=18/32; 56%) and moderately strong/strong skp-2 expression (n=18/32; 56%), respectively, in over half the cases. MST of intercalated duct origin showed evident p27/skp-2 inverse correlation. Differences in p27/skp-2 expression among the MST subtypes correlated with histogenesis and tumor grade, which reinforces the notion that tumor behavior is relevant to the portion of the salivary gland unit from which they arise. MST of proposed intercalated duct origin strongly expressed p27, and not skp-2, unlike MST of proposed excretory duct origin. The immunohistochemical profile of high grade mucoepidermoid carcinoma was distinct from its low/intermediate grade counterparts, suggesting a separate identity. These results may influence future decision making when formulating workable MST categorization schemes. Further studies on a larger series of MST are warranted in order to support the value of our findings.

High-Grade Mucoepidermoid Carcinoma of the Larynx

Laryngeal mucoepidermoid carcinoma is rare. Approximately 85 cases have been reported in the literature. There is no standardized treatment because of the rarity of the disease. A case of a 55-year-old man with laryngeal mucoepidermoid carcinoma, who was treated with total laryngectomy and postoperative radiotherapy, is presented, and current literature is reviewed.

Pediatric Mucoepidermoid Carcinomas (MEC) Of The Salivary Glands: Implications On Postoperative Radiation Therapy

Salivary gland tumors (SGT) represent 1% of head and neck tumors Only 5% of these occur in patients (pts) younger than 20 years, in whom MEC is the most frequent histology. Radiation therapy (RT) is recommended for high grade and/or T3 - 4 and discussed in other clinical situations on a case-by-case basis in adult SGT. We investigated the role of radiation therapy in a pediatric population. This survey was conducted among 34 French pediatric oncology departments for cases included between 1980 and 2010. There 38 patients (median age 14 (4 - 18); 51% male), of whom 36% and 25% had a history of cancer and irradiation, respectively. Tumors involved the parotid, submandibular gland and minor salivary glands in 82%, 10% and 8%, respectively. Tumors were of high, intermediate and low grade in 14%, 19% and 67%, respectively. Stage distribution was 83% and 17% for T1 - 2 and T3 - 4 respectively with a median size of 2.5 cm (1.5 - 4). 11% of cases were node positive, none was metastatic. All but one (who had simultaneous relapse of his medulloblastoma, of which he died within one month) underwent surgery of the primary, 79% with clear margins, 13% (N = 4) with nerve sacrifice. Neck dissection was performed in 52%. Adverse prognosis factors included perineural invasion, vascular emboli and bone involvement in 19%, 13% and 3%, respectively. RT was performed in 23% of pts: 17%, 14% and 75% of grade 1, 2 and 3 tumors, respectively; 22%, 14%, 50%, 67% of T1, 2, 3 and 4 tumors, respectively and in 22% of previously irradiated pts vs 25%. The overall, local, regional and metastatic relapse rates were 19%, 16%, 3% and 3%, respectively. Most pts (94%) are alive with mean follow-up of 71 months. 3% died of MEC, 3% of other causes (mostly from other cancer). Local relapse occurred in 17% of pts undergoing RT and 24% of pts with surgery only (NS). On univariate analysis, prior RT, prior cancer, site, stage, did not impact on local control. There was a trend in favor of complete resection. Given the similar local control rates within T3 - 4 and high grade MEC, which have a high risk of relapse, RT probably added a benefit in this subset of pts. Pediatric MEC is of good prognosis. Most tumors are of low grade. RT can be recommended for high grade MEC but indications of RT for low or intermediate grades should be weighted with other poor prognosis factors against the risk of craniofacial growth defect and secondary cancer.

Expression of the Vascular Endothelial Growth Factor and Angiopoietins in Mucoepidermoid Carcinoma of Salivary Gland

Disrupted coordination of angiogenesis regulating signals, among them the vascular endothelial growth factor (VEGF) and angiopoietins (Angs), has been associated with abnormal angiogenesis and tumor progression. While VEGF induces endothelial cell proliferation, thereby initiating vessel formation, Angs are subsequently required for mural cell attachment, thus influencing remodeling and maturation of this vasculature. In addition to tumor cell, endothelial and mural cells, as well as myofibroblasts may also contribute to the secretion of these factors. In this study, we have analyzed by immunohistochemistry the expression of VEGF, Ang-1, Ang-2 and the Angs receptor Tie2 in both the stroma and tumor cells of mucoepidermoid carcinoma (MEC) of salivary gland. We have demonstrated that when myofibroblasts were detected adjacent to the cancer cells, they were frequently associated with intense positive staining for Ang-1 and Ang-2, and no reactivity to VEGF and Tie2. These myofibroblast-rich Ang-1 and Ang-2-stained areas were more commonly found in high-grade MEC cases than in low-grade ones. As for the malignant cells, they frequently expressed all proteins studied, but Ang-2 and VEGF were detected at higher levels compared to Ang-1 and Tie2. Our results indicate that the MEC environment favors cooperative activity between Angs and VEGF in modulating vascular growth and tumor aggressiveness.

MRI findings of mucoepidermois carcinoma of the parotid gland: correlation with pathological features

The aim of this study was to correlate the MRI appearance and pathological findings in each grade of the mucoepidermoid carcinoma (MEC) of the parotid gland. We reviewed surgically proven MECs of parotid glands in 20 patients. Pathologically, 5 tumours were high-grade, 3 were intermediate and 12 were low-grade. MR images were evaluated with emphasis on signal intensities on T(2) weighted images, margin characteristics and lymph node metastasis, correlating these with pathological features. Among the high-grade MECs, four out of five tumours showed inhomogeneous low to intermediate signal intensity on T(2) weighted images, reflecting high cellularity. All tumours had an ill-defined margin, reflecting invasive tumour growth. Among the intermediate-grade MECs, all three tumours showed intermediate signal intensity on T(2) weighted images and two tumours had an ill-defined margin. Among the low-grade MECs, 11 of the 12 tumours had a hyperintense area on T(2) weighted images because of the existence of abundant mucin secreting cells. Seven tumours had an ill-defined margin, reflecting peritumoural inflammatory changes rather than invasive tumour growth. Lymph node metastasis was seen in three high-grade MECs. MECs of the parotid gland show variable MRI findings reflecting their histological nature, which seems to have certain tendencies depending on the tumour grade.

Increased telomerase activity and hTERT expression in human salivary gland carcinomas

Approximately 85% of human malignant tumors express increased levels of telomerase. The marked association of telomerase activity with malignant tissue provides strong evidence that telomerase activity is a significant marker for the diagnosis of cancer. In this study, telomerase activity was examined in 12 benign salivary gland tumors (8pleomorphic adenomas and 4 adenolymphomas), 24malignant tumors (15mucoepidermoid carcinomas, 6adenoid cystic carcinomas and 3 acinic cell carcinomas) and 6 non-neoplastic salivary glands. The mRNA expression of the human telomerase reverse transcriptase (hTERT) and additional telomerase‑associated proteins (hTEP1, p23, Hsp90 and dyskerin) was also examined. Of the 24malignant tumors, 15 revealed strong telomerase activity. The non-neoplastic salivary glands appeared to have a negative telomerase expression. Furthermore, telomerase activity was significantly higher in high-grade mucoepidermoid carcinomas compared to low‑grade ones (Student's t-test, p<0.05). A significant correlation was found between telomerase activity and mRNA expression of hTERT in 15cases, including non-neoplastic salivary glands and tumors (Spearman's rank correlation test, p<0.05). Furthermore, a significant correlation was found between telomerase activity and mRNA expression of EGFR (Spearman's rank correlation test, p<0.001). The results suggest that not only hTERT, but also EGFR play a significant role in the activation of telomerase. In conclusion, the results suggest that telomerase activity and hTERT/EGFR mRNA expression are useful markers for the detection of malignant cells in salivary gland carcinomas. Moreover, our results indicated that telomerase activity determines the degree of malignancy of mucoepidermoid carcinoma.

Lymphatic vessel density and expressions of lymphangiogenic growth factors in salivary carcinomas

Nodal metastasis is an important prognostic indicator in head and neck cancers, including salivary carcinomas. In these, the risk for lymph node metastasis is variable and strongly associated with the tumor histologic type. The aim of the current study was to evaluate the lymphatic vessel density (LVD) and expressions of lymphangiogenic growth factors by tumor cells in different histologic types of salivary carcinomas subdivided according to the risk for nodal metastasis. In 15 high-risk (undifferentiated, high-grade mucoepidermoid and salivary duct carcinomas) and 60 low/moderate-risk tumors (adenoid cystic, low/intermediate-grade mucoepidermoid, acinic cell, myoepithelial, epithelial-myoepithelial and polymorphic low-grade carcinomas) the expressions of vascular endothelial growth factor-C (VEGF-C), hepatocyte growth factor (HGF) and D2-40 (for assessing LVD) were examined. No significant differences were encountered between high- and low/moderate/-risk carcinomas regarding LVD and VEGF-C or HGF expressions. Furthermore, the expression of these proteins did not correlate with LVD. Lymphatic vascular invasion was found mainly in high-risk carcinomas. Intratumoral LVD was significantly lower than peritumoral, regardless of the risk for metastasis and primary site of the lesion. The histologic types of salivary carcinomas which are associated with high-risk for nodal metastasis do not present increased LVD or VEGF-C and HGF expressions. The greater tendency for metastasis in these carcinomas seems to be related to their capacity to invade lymph vessels. Further studies on tumor cell interactions with lymphatic endothelial cells are needed to improve our understanding of the metastatic potential of salivary carcinomas.

Mucoepidermoid Carcinoma of the Lacrimal Sac After Dacryocystectomy for Squamous Papilloma

A mass that recurred after dacryocystectomy for benign squamous papilloma of the lacrimal sac was diagnosed as a high-grade mucoepidermoid carcinoma in a 53-year-old man on histopathology. Local excision to the orbital periosteum was performed and gave a margin free of invasion. Neither local recurrence nor systemic metastasis was found 3 years after local excision. Mucoepidermoid carcinoma of the lacrimal sac is extremely rare and spreads locally in an aggressive manner; a cure typically requires exenteration, radical resection, or adjuvant radiotherapy. In this rare case, despite the high malignancy, the patient underwent successful local excision, achieved an aesthetically satisfying result, and has had a long-term cancer-free period.

Mucoepidermoid carcinoma: a five-decade journey

Several decades after a comprehensive description of mucoepidermoid carcinoma (MEC), there is no uniformly accepted grading system. The most recent debate regarding the histologic grading of MECs, centers on the wide range of reported prevalence of cyclic AMP response element-binding protein (CREB)-regulated transcription coactivator (CRTC1-MAML2) rearrangement in high-grade (HG) MECs. We hypothesize that difficulties in morphologic classification may partially explain problems in grading MECs. We believe that HG MECs, as diagnosed over the last several decades, represent a blend of true MECs with unrelated clinicopathologic entities. To examine the historic aspects of this problem, and to identify neoplasms that most commonly mimic "high-grade" MEC, we reviewed 46 cases of alleged MEC diagnosed in our department from 1956 to 1974. The diagnosis of MEC was confirmed in 22 cases and was changed in 24 cases. Compared to cases of confirmed MEC, cases with changed diagnoses had higher incidence of lymph node metastases, perineural invasion, and shorter overall survival. Adenosquamous carcinoma, squamous cell carcinoma, and salivary duct carcinoma emerged as the most common mimics of HG MEC. The single most common diagnostic issue in these cases is the level of keratinization acceptable for MEC. Twenty cases of confirmed MEC were tested for CRTC1-MAML2 rearrangement and 5 low-grade MECs, 7 intermediate grade MECs, and 2 cases of HG MEC were translocation-positive.

Mucoepidermoid Carcinoma of Tracheobronchial Tree: Clinicopathological Study of 31 Cases

BACKGROUNDAll aspects of mucoepidermoid carcinoma (MEC) of the lung including histologic grading, clinical behavior and its differentiation from adenosquamous cell carcinoma are still not fully understood.METHODSWe reviewed the hematoxylin-eosin stained slides and medical records of 31 cases of MEC of the lungs. The cases were classified as low and high grade according to the quantitative grading system formulated for MEC. High grade tumors were tested for an epidermal growth factor receptor (EGFR) mutation.RESULTSTwenty eight cases were classified as low grade and 3 cases as high grade. Histologically, lower glandular component, cellular atypia, necrosis, mitoses >4/10 high power fields, and endolymphatic tumor emboli were typical characteristics of a high grade tumor. Although some tumors showed histologic features mimicking high grade tumors, they were classified as low grade tumors according to this quantitative grading system. Low grade tumors showed no recurrence or metastasis. However, among three patients with a high grade tumor, two had distant metastases and one died of disease. Additionally, an EGFR mutation was not detected.CONCLUSIONSA high grade MEC was consistently different from a low grade tumor with regard to malignant histologic features and poor prognosis. Therefore, correct histologic grading is important in predicting the prognosis to avoid unnecessary treatment.

Salivary duct carcinoma: Correlation of morphologic features by fine needle aspiration cytology and histopathology

Salivary duct carcinoma (SDC) is a highly aggressive primary salivary gland neoplasm that resembles intraductal and infiltrating breast carcinoma. To review cytomorphologic features of histology proven SDC and evaluate potential pitfalls in cytologic diagnosis. Fine needle aspiration cytology (FNAC) of five histologically proven SDCs were reviewed. One patient was an elderly male (61 years), while the other four patients were younger, in their fourth decade (average age: 38 years). The initial cytologic diagnoses in two of the cases were poorly differentiated carcinoma with differential diagnosis of SDC and high grade mucoepidermoid carcinoma, while in the third case, a possibility of malignant mixed tumor was suggested. In fourth and fifth cases, the diagnosis was suggestive of pleomorphic adenoma with cystic change. The spectrum of cytologic changes included flat sheets and cohesive papillary and three-dimensional clusters. There was moderate to severe nuclear pleomorphism and atypia. Cribriform pattern and necrosis were occasionally identified. Prominent bright granular metachromatic stroma was seen in two of the cases interpreted as pleomorphic adenoma with cystic change and in the tumor reported as suggestive of malignant mixed tumor. The fifth case showed numerous cyst macrophages and apocrine cells with mild nuclear atypia. FNAC of SDC is difficult to interpret because of overlapping cytomorphologic features. Bland cytomorphologic features in some cases and several clinical pitfalls are demonstrated in our series.

Central mucoepidermoid carcinoma of the mandible: A case report

Primary central salivary gland carcinomas of the mandible are uncommon neoplasms. Mucoepidermoid carcinoma is a distinct pathologic entity of the salivary glands and comprises 5-10% of all salivary gland tumours. Central mucoepidermoid carcinomas (CMC) are extremely rare, comprising 2-3% of all mucoepidermoid carcinomas reported. This is a case report of central mucoepidermoid carcinoma of the anterior region of the mandible in a 37 year old female patient. Histopathological findings revealed a fibrous connective tissue within which are scattered islands, sheets and cords of neoplastic epidermoid and intermediate cell clusters exhibiting cellular pleomorphism and nuclear hyperchromatism. A diagnosis of central high grade mucoepidermoid carcinoma was made. The patient was thereafter referred to a tertiary institution with facilities for radiotherapy on account of the grade of the tumour.

Expression pattern of claudins 1 and 3—an auxiliary tool in predicting behavior of mucoepidermoid carcinoma of salivary gland origin

Claudins (CLDNs) are a family of membrane proteins important for permeability of tight junctions. They have also been implicated in carcinogenesis and tumor progression. We analyzed patterns of distribution and intensity of expression of CLDNs 1, 3, 4, and 7 in mucoepidermoid carcinoma (MEC) of salivary gland in 39 patients. Correlations between the expression of CLDNs, tumor grade, and survival were explored. In immunohistochemical analysis, high expression of CLDN 1 was seen in low-grade MEC, and it appeared to be a suitable auxiliary marker of good prognosis. It classified MEC similarly to histological grading in 89.7% of cases (p = 0.001). High CLDN 3 expression was seen in intermediate- and high-grade MEC, while it was low in low-grade MEC. CLDN 3 intensity correctly categorized tumors into grades in 71.8% of cases (p = 0.017). However, in multivariate analysis CLDN 1 and CLDN 3 did not achieve significance over tumor grade in predicting patient behavior. We conclude that analysis of staining intensities of CLDN 1 and 3 is useful as an auxiliary diagnostic and prognostic tool in patients with salivary gland MEC.

A Reappraisal of the MECT1/MAML2 Translocation in Salivary Mucoepidermoid Carcinomas

The MECT1/MAML2 translocation is identified in a large proportion of mucoepidermoid carcinomas (MEC) of the salivary gland and is an emerging favorable prognosticator. However, there are conflicting data on this translocation's specificity, restriction to low/intermediate MEC, and strength as a prognosticator. We present our experience with the MECT1/MAML2 translocation in a large cohort of MECs to address these issues. We analyzed 55 salivary MEC and 36 potential MEC mimics (24 Warthin tumors, 5 oncocytomas, 3 squamous cell carcinomas, 2 squamoid salivary duct carcinomas, 1 lymphoepithelial cyst, 1 Schneiderian carcinoma ex papilloma) for presence of the MECT1/MAML2 translocation by fluorescent in-situ hybridization (FISH) and real-time RT-PCR. Overall, MECT1/MAML2 translocation was present in 36/55 (66%) of MEC whereas all 36 non-MEC were negative for translocation. Low or intermediate-grade MEC had a higher frequency of translocation (75%) than high-grade MEC (46%) (P=0.039). Translocation positive cases had a better disease-specific survival (log rank P=0.026) although 2 patients still died of disease. Within high-grade MEC, MECT1/MAML2 positive tumors had lower rates of anaplasia (P=0.001), and mitotic counts (P=0.012). Thus, MECT1/MAML2 translocation is highly specific for MEC and imparts a better prognosis. However, it is frequent even within high-grade MEC and can be seen in lethal cases suggesting that translocation status should not supersede conventional parameters. There are 2 distinct subgroups within high-grade MEC, and the translocation negative tumors may actually be more appropriately categorized as another tumor type (such as adenosquamous carcinoma).

Activation of the EGFR/ERK pathway in high-grade mucoepidermoid carcinomas of the salivary glands

Background:Mucoepidermoid carcinoma (MEC) shows differences in biological behaviour depending mainly on its histological grade. High-grade tumours usually have an aggressive biological course and they require additional oncological treatment after surgery.Methods:In a series of 43 MECs of the salivary glands, we studied the epidermal growth factor receptor (EGFR) gene by using dual-colour chromogenic in situ hybridisation (CISH). Moreover, we assessed the protein expressions of the EGFR and the activated extracellular signal-regulated kinases (pERK1/2) by using immunohistochemistry. These results were correlated with the histological grade of the tumours and the outcome of the patients.Results:The CISH study demonstrated a high-EGFR gene copy number, with balanced chromosome 7 polysomy, in 8 out of 11 high-grade MECs (72.7%), whereas 27 low-grade and 15 intermediate-grade tumours had a normal EGFR gene copy number (P<0.001). The EGFR gene gains correlated with disease-free interval (P=0.003) and overall survival of the patients (P=0.019). The EGFR protein expression had a significant correlation with the histological grade of the tumours but not with the outcome of the patients. The pERK1/2 expression correlated with histological grade of tumours (P<0.001), disease-free interval (P=0.004) and overall survival (P=0.001).Conclusions:The EGFR/ERK pathway is activated in high-grade MECs with aggressive behaviour. Patients with these tumours who require oncological treatment in addition to surgery could benefit from EGFR and mitogen-activated protein kinase pathway inhibitors.

Survival in oral cavity minor salivary gland carcinoma

Objective To describe the epidemiology and comparative survival for minor salivary gland cancer of the oral cavity. Study Design Historical cohort study. Setting Academic medical center. Subjects and Methods Cases of minor salivary gland cancer of the oral cavity were extracted from the Surveillance, Epidemiology, and End Results database (1988-2005) and staged. Kaplan-Meier survivals were compared according to histology as well as T stage and N stage. A Cox proportional hazards model incorporating histology, T stage, N stage, age, and sex was analyzed. Results A total of 639 salivary gland cancers of the oral cavity (55% female; mean age, 56 years) were identified with complete staging information, consisting of 318 mucoepidermoid, 169 adenoid cystic, 139 adenocarcinoma, and 14 acinic cell cancers. The hard palate and gums were the most common subsites involved (87.6%), followed by lip (7.2%) and tongue (5.2%). At presentation, T1 and T4 tumors predominated (42.6% and 35.2%, respectively); 93.4 percent were N0. Overall mean survival (months) was 157.9 and was similar across histologic subtypes: mucoepidermoid (172.4), adenoid cystic (141.4), acinic cell (138.7), and adenocarcinoma (147.2). Survival for low- and intermediate-grade mucoepidermoid carcinoma (171.0 and 182.3, respectively) was better than survival for high-grade mucoepidermoid carcinoma (50.3, P < 0.001). On multivariate analysis, N stage ( P < 0.001) was the most powerful predictor of survival, along with T stage ( P = 0.013), age ( P < 0.001), and sex ( P < 0.001). Conclusion T stage and N stage are the most powerful predictors of survival in minor salivary gland carcinoma of the oral cavity. With the exception of high-grade mucoepidermoid carcinoma, survival for these lesions is generally favorable.

High-grade oncocytic mucoepidermoid carcinoma of the minor salivary gland origin: a case report with immunohistochemical study

An oncocytic mucoepidermoid carcinoma arising from the minor salivary gland origin is extremely rare. We report on a 44-year-old man with a high-grade oncocytic mucoepidermoid carcinoma originating in the minor salivary gland of the posterior mandible. All tumor cells showed the expected pattern of immunoreactivity, with positive results for the antimitochondrial antibody and p63, and negative results for the androgenic receptor antibody. Microscopically, the tumor was considered to be a high-grade carcinoma in the grading systems of the Armed Forces Institute of Pathology and Brandwein. The patient underwent a partial mandibulectomy, and the lesion was reconstructed with a right fibula osteofasciocutaneous flap under general anesthesia. The patient is currently under long-term follow-up.

Baicalin induces human mucoepidermoid carcinoma Mc3 cells apoptosis in vitro and in vivo

Mucoepidermoid carcinoma (MEC) is the most common malignant tumor in salivary glands and high-grade MEC in particular demonstrates little response to chemotherapy which has been used largely for palliative treatment of metastatic disease. Baicalin, one of the main active compounds of Scutellaria baicalensis, possesses anti-inflammatory, antioxidant and antitumor properties. In the present study, we investigated the growth inhibiting and apoptosis-inducing effects of baicalin on a highly metastatic human mucoepidermoid carcinoma cell line Mc3 for the first time. Baicalin exerted dose- and time-dependent antiproliferative potential against Mc3 cells as assessed by MTT assay. Baicalin treatment of Mc3 cells resulted in an accumulation of cells at the G₀/G₁ and G₂/M phase with a concomitant decrease in cells processing to S phase as assessed by flow cytometry. Furthermore, baicalin induced apoptosis of Mc3 cells as determined by annexin V binding and PI dual staining, DNA fragmentation, nuclear condensation and in vivo tumor inhabitation. Rhodamine 123 assay indicated that baicalin caused cytotoxicity and induced apoptosis through decreasing the mitochondrial membrane potential in Mc3 cells. Our results suggest that baicalin seems to be very attractive as a new anticancer drug and a potential chemotherapeutic agent against human high-grade mucoepidermoid carcinoma.

Mucoepidermoid carcinoma of the tracheobronchial tree: CT findings

Objective To explore the CT findings of mucoepidermoid carcinoma (MEC) of the tracheobronchial tree and improve the diagnostic accuracy. Methods The CT images, histopathological and clinical data in 24 patients with pathologically proved MEC of the tracheobroncbial tree were retrospectively analyzed. Results The clinical symptoms included cough, sputum, fever, wheezing, chest pain and hemoptysis. The patient was proved to be low-grade (n=19) and high-grade (n=5) MEC histopathologically. One lesion was located in trachea, 6 in main bronchus, 12 in lobar bronchus and 5 in segmental, subsegmental and distal bronchus. The tumor presented as no-invasive endotracheobronchial well-defined round-like nodule (n=13, locating in lobar and higher bronchus) and columnar sharp (n=3, locating in main bronchus), or intra-and-extraluminal well-defined round-like nodule or mass (n=6, locating in lobar and lower bronchus) and irregular mass with invasive pattern (n=2, high-grade type). The density of lesion was similar to the muscule and the calcification within lesion was showed in 4 patients on non-enhanced CT. The lesion had marked enhancement in 17 patients on enhanced CT. Obstructive changes were found in 20 patients. Conclusion MEC of the tracheobronchial tree is usually low-grade malignancy and locates in main and lobar bronchus with no-invasive well-defined airway mass, marked enhancement and calcification on CT. Key words: Respiratory tract neoplasms; Carcinoma, mucoepidermoid; Tomography,X-ray computed; Diagnosis

Synchronous ipsilateral Warthin tumor encased by a separate mucoepidermoid carcinoma of the parotid gland: A case report and review of the literature

Fine-needle aspiration (FNA) is a cost effective and low morbidity procedure in the initial assessment of salivary gland tumors. However, cytological assessment of ipsilateral synchronous tumors (which make up less than 0.3% of all salivary gland neoplasms) may pose diagnostic challenges. Therefore, a wholesome approach, including FNA with clinical and radiological correlation, is of utmost importance. Here, we report a unique case of Warthin tumor encased by a separate high-grade mucoepidermoid carcinoma that was first diagnosed on FNA. Another striking feature seen was the presence of chronic sialadenitis in the surrounding nonneoplastic salivary gland. The presence of two different neoplasms in the background of chronic sialadenitis raises the question of a possible causal relationship. Traditionally, there has been diagnostic difficulty when dealing with synchronous tumors of the salivary gland and the background of chronic sialadenitis may further complicate the diagnosis. FNA is very helpful and can give important cues to the diagnosis.