Mucoepidermoid carcinoma of the thymus is an extremely rare malignant mediastinal neoplasm, and to our knowledge, only 13 cases have been reported. We report a case of mucoepidermoid carcinoma of the thymus that was seen in a 53-yr-old man with right chest pain. Chest CT scan showed a huge, cystic mass having a focal solid portion with direct invasion of the adjacent anterior chest wall and pericardium in the anterior mediastinum. Mucoepidermoid carcinoma of the thymus should be included in the differential diagnosis for masses of the anterior mediastinum associated with extensive cystic changes, although the carcinoma is exceedingly rare.
Carcinoma, Mucoepidermoid/*diagnosis/pathology ; Fatal Outcome ; Humans ; Male ; Mediastinal Neoplasms/*diagnosis/pathology ; Middle Aged ; Thymus Neoplasms/*diagnosis/pathology

Adamantinoma ; pathology ; Carcinoma, Mucoepidermoid ; diagnostic imaging ; drug therapy ; pathology ; surgery ; Diagnosis, Differential ; Humans ; Male ; Mandibular Neoplasms ; diagnostic imaging ; pathology ; surgery ; Middle Aged ; Tomography, X-Ray Computed

Adenocarcinoma, Clear Cell ; metabolism ; pathology ; surgery ; Adult ; Carcinoma ; metabolism ; pathology ; Carcinoma, Mucoepidermoid ; metabolism ; pathology ; Carcinoma, Renal Cell ; metabolism ; pathology ; secondary ; Diagnosis, Differential ; Humans ; Keratins ; metabolism ; Male ; Nasal Cavity ; Nose Neoplasms ; metabolism ; pathology ; surgery ; S100 Proteins ; metabolism

OBJECTIVE: To investigate clinical and pathological characteristics of lung mucoepidermoid tumors and summarize methods for diagnosing and treating it. METHODS: Records of a total of 2,751 consecutive patients with lung cancer were reviewed and 10 of whom with mucoepidermoid tumors were identified. Chest radiographs, computer tomographs, and bronchoscopes were performed to all of them. Eight of them underwent thoracotomy and some also received chemotherapy and/or radiotherapy. One patient received Chinese herb therapy only while another did not receive any therapy. RESULTS: Pathological examination showed that the 10 patients had low-grade mucoepidermoid tumors. All patients were alive. Seven patients who received thoracotomy did not recur. One patient whose tumor was located in trachea recurred 5.2 years after the operation. CONCLUSION Bronchoscope can play an important role in the process of diagnosis. Pathological staging is vital for prognosis. Lung mucoepidermoid tumors should be treated with complete surgical resection with lymph node sampling and dissection and close follow-up.
Adolescent ; Adult ; Bronchoscopy ; Carcinoma, Mucoepidermoid ; drug therapy ; pathology ; surgery ; Female ; Follow-Up Studies ; Humans ; Lung Neoplasms ; diagnosis ; pathology ; surgery ; Male ; Middle Aged ; Young Adult

A 50-yr-old male presented a thyroid mass with dysphasia and hoarseness. He underwent total thyroidectomy and neck node dissection. Pathologically, the tumor had two distinct tumor components with intermingled areas: follicular variant of papillary carcinoma and mucoepidermoid carcinoma. Mucoepidermoid carcinoma composed of columnar cells, mucocytes, and squamoid cells showing solid and cystic lesion. Several small cysts lined by benign ciliated columnar epithelia suggesting that this tumor had originated from solid cell nest were seen around the tumor. By immunohistochemistry, columnar cells and squamoid cells in mucoepidermoid carcinoma were positive for cytokeratin but negative for thyroglobulin, TTF-1 and calcitonin. Positivity of p63 was seen in squamoid cells and basal cells of cysts. Some mucocytes are CEA positive. Tumor cells of papillary carcinoma are positive for TTF-1, thyroglobulin but negative for CEA, calcitonin and p63.
Calcitonin/metabolism ; Carcinoma, Mucoepidermoid/*diagnosis/pathology ; Carcinoma, Papillary/*diagnosis/pathology ; Humans ; Immunohistochemistry ; Keratins/metabolism ; Male ; Membrane Proteins/metabolism ; Middle Aged ; Nuclear Proteins/metabolism ; Thyroglobulin/metabolism ; Thyroid Neoplasms/*diagnosis/pathology ; Transcription Factors/metabolism

BACKGROUND: Controversy exists concerning the utility of fine needle aspiration cytology (FNAC) in diagnosing salivary masses. Thus, the goal of this study was to evaluate the efficacy of preoperative fine needle aspiration cytology compared with those of frozen section (FS) and final histopathologies in terms of sensitivity, specificity, accuracy and pitfalls. METHODS: A total of 66 aspirates were from the salivary gland, 50 (75.8%) from the parotid gland and 16 (24.2%) from the submandibular gland, from Jan. 1990 to Jul. 1998. The results from 49 of 66 aspirates were compared with the results from frozen-section pathology. RESULTS: The 66 cases included 59 cases of benign lesions (49 cases of pleomorphic adenomas, 4 cases of basal cell adenomas, 3 cases of Warthin's tumors, and 3 cases of other benign tumors) and 7 cases of malignant lesions (3 cases of mucoepidermoid carcinomas and 4 cases of other malignant tumors). The accuracy in distinguishing malignant from benign lesions was 89.4% for FNAC. The sensitivity, the specificity, and the type-specific accuracy of FNAC were 89.7%, 96.3%, and 70.0%, respectively. A comparison of the cytopathologic diagnosis and the FS diagnosis was made. The accuracy of the FS in distinguishing malignant lesions was 93.8%. The sensitivity, the specificity, and the type-specific accuracy of FS were 80.0%, 95.4%, and 87.7%, respectively. The salivary gland tumors mainly misdiagnosed in FNAC were basal-cell adenomas and Warthin's tumor in benign disease and mucoepidermoid carcinomas in malignant tumors. CONCLUSION: Though FNAC still has some problems and pitfalls, the comparative accuracies of FNAC and FS are similar. A review of the value of FS diagnosis in the surgical treatment of salivary gland lesions suggests that FS diagnosis alone should not determine the surgical management of salivary gland tumors. FNAC is a sensitive and specific diagnostic tool and is complementary to a frozen section biopsy of a salivary gland mass.
Adenoma ; Adenoma, Pleomorphic ; Biopsy ; Biopsy, Fine-Needle* ; Carcinoma, Mucoepidermoid ; Diagnosis ; Frozen Sections ; Parotid Gland ; Pathology ; Salivary Glands* ; Sensitivity and Specificity ; Submandibular Gland

Objective: To study the clinicopathologic and genetic features of papillary cystic low-grade mucoepidermoid carcinoma (LG-MEC) and cystadenoma. Methods: A retrospective review was performed on salivary gland tumor patients with papillary cystic architecture who presented to department of oral pathology, Peking University School and Hospital of Stomatology between January 2010 and June 2022. Among this cohort, there were 17 males and 17 females with a range age of 23-82 years [(55.6±14.6) years]. Diagnosis was confirmed by histological, immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) analysis. Finally, 15 papillary cystic LG-MEC and 19 cystadenoma patients were included in the present study. All patients were followed clinically and radiologically, and the duration of follow-up ranged from 1 to 141 months. Results: All neoplasms showed papillary proliferation with multilocular or giant cystic tumors. Papillary cystic LG-MEC was characterized by epidermoid cells, intermediate cell and mucous cells with multiple lining-layers. Papillary cystic LG-MEC had mild cellular atypia and a pushing infiltration. Cystadenoma was characterized by cuboidal, columnar and ciliated pseudostratified columnar lining epithelium. Squamous metaplasia, mucinous metaplasia and acidophilic degeneration could also be observed focally in cystadenoma. For IHC staining, papillary cystic LG-MEC showed diffusely and strongly positive for mucin 4 (MUC4) (15/15) and mucin 5 Subtype AC (MUC5AC) (4/15) in the epidermoid cells, intermediate cell and mucous cells. The epidermoid cells and intermediate cells were diffusely positive for p40 and p63. The Ki-67 index was about 10%-15% in LG-MEC. As a contrast, p40 (17/19) and p63 (14/15) were only detected in the basal cells of cystadenoma. Cystadenoma showed focal MUC5AC (4/19)expression and MUC4 (19/19)diffuse expression. In addition, the Ki-67 index was 5%-10% in cystadenoma. The MAML2 gene translocation was detected in 11 LG-MEC patients, but none in cystadenoma. Conclusions: The differential diagnosis points between papillary cystic LG-MEC and cystadenoma included the specific epidermoid cells, intermediate cells and mucus cells in LG-MEC, cell atypia, the pushing-infiltration pattern, diffuse expression of p40 and p63 in the lining epithelium, and a MAML2 gene rearrangement. The molecular test of MAML2 should be recommended to reduce missed LG-MEC diagnoses.
Male ; Female ; Humans ; Carcinoma, Mucoepidermoid/pathology* ; In Situ Hybridization, Fluorescence ; Ki-67 Antigen/genetics* ; Biomarkers, Tumor/analysis* ; Salivary Gland Neoplasms/diagnosis* ; Transcription Factors/metabolism* ; Cystadenoma ; Metaplasia

OBJECTIVETo describe the fine needle aspiration cytology (FNAC) features of various salivary gland lesions and to analyze the respective diagnostic value and pitfalls.

METHODS113 FNAC specimens of salivary gland lesions were reviewed and correlated with clinical and histopathologic findings.

RESULTSThe FNAC diagnostic failure (2); non-neoplastic lesions (12); benign neoplasm (82) and malignant neoplasm (17). Cytologically, the distinction between cellular pleomorphic adenoma, adenoid cystic carcinoma and basal cell adenoma could be difficult due to their overlapping morphologic features. The cytologic patterns of primary lymphoepithelial carcinoma of the parotid were indistinguishable from those of metastatic nasopharyngeal undifferentiated carcinoma. The ultimate distinction relied on clinical correlation. The three inaccurately diagnosed cases of FNAC are, as follows: reactive lymphoid hyperplasia of lymph node mistaken as non-Hodgkin lymphoma, mucoepidermoid carcinoma diagnosed as "scanty atypical cells present" and primary lymphoepithelial carcinoma mistaken as benign lymphoepithelial lesion. On the basis of FNAC, 97.4% (110 /113) were correctly depicted as benign (95/96; 99.0%) or malignant (15/17; 88.2%). Furthermore, 90.3% (102 /113) (specificity = 91.9%; 102/111) were accurately diagnosed, including 91.7% (88/96) benign lesions (specificity = 92.6% ; 88/95) and 82.4% (14/17) malignant tumors (specificity = 87.5%; 14/16).

CONCLUSIONSFNAC is reliable in distinguishing benign and malignant salivary gland lesions. A specific cytologic diagnosis is often possible. On the other hand, due to the pitfalls in cytologic diagnosis of certain salivary gland tumors, tissue biopsy for histologic examination may be necessary.

Adenolymphoma ; pathology ; Adenoma ; pathology ; Adenoma, Pleomorphic ; pathology ; Adolescent ; Adult ; Aged ; Biopsy, Fine-Needle ; Carcinoma, Adenoid Cystic ; pathology ; Carcinoma, Mucoepidermoid ; pathology ; Carcinoma, Squamous Cell ; pathology ; Child ; Diagnosis, Differential ; Diagnostic Errors ; Female ; Humans ; Male ; Middle Aged ; Parotid Neoplasms ; pathology ; Retrospective Studies ; Salivary Gland Neoplasms ; pathology ; Salivary Glands ; pathology ; Submandibular Gland Neoplasms ; pathology

Carcinoma, Mucoepidermoid ; complications ; metabolism ; pathology ; DNA-Binding Proteins ; metabolism ; Diagnosis, Differential ; Eosinophilia ; complications ; metabolism ; pathology ; Epithelial Cells ; pathology ; Female ; Hashimoto Disease ; metabolism ; pathology ; surgery ; Humans ; Keratin-19 ; metabolism ; Membrane Proteins ; metabolism ; Middle Aged ; Thyroid Gland ; metabolism ; pathology ; surgery ; Thyroid Nodule ; metabolism ; pathology ; surgery ; Transcription Factors ; beta Catenin ; metabolism