A hybrid carcinoma of epithelial-myoepithelial carcinoma and adenoid cystic carcinoma in maxillary sinus

Hybrid carcinoma of the salivary gland is a very rare entity that has been described only in the parotid and palate. The occurrence of a hybrid carcinoma of maxillary sinus has not been reported. The diagnosis of hybrid carcinoma is important particularly when the components of tumor have different biologic behaviors. Diagnosis and treatment require a high index of suspicion, especially when the tumor is an epithelial-myoepithelial carcinoma, pathological effort to look for a more aggressive accompanying tumor, and proper oncologic treatment. We describe a case of 26-yr-old woman with a hybrid carcinoma composed of epithelial-myoepithelial carcinoma with an adenoid cystic carcinoma component (cribriform pattern) in the right maxillary sinus with a brief review of the relevant literature.     

Bronchial carcinoma and hypercalcaemia

Hypercalcaemia due to malignant disease, in the absence of bone metastases, is generally regarded as a rare event. It occurred in 16% of a series of cases of bronchial carcinoma coming to necropsy. Hypercalcaemia is a relatively common complication of bronchial carcinoma.The hypercalcaemia is usually accompanied by hypophosphataemia and, in this respect, must be distinguished from the hypercalcaemia that may be found with breast carcinoma. It is frequently accompanied by hypokalaemic alkalosis; this must not be confused with the metabolic disorder that results from the production of ectopic ;ACTH'.The bones sometimes show changes of osteitis fibrosa akin to those seen in hyperparathyroidism. Cystic disease of bone recognizable radiologically is rare, probably because of the relatively short duration of the metabolic disturbance.The parathyroids are usually mildly atrophic. There is no evidence that the main pathogenetic mechanism is stimulation of the parathyroids by the tumour. Acceptable instances of parathyroid hyperplasia are very rare: the significance of these exceptional cases awaits further study.Squamous carcinoma of the bronchus is the type mainly incriminated. Oat-cell carcinoma and bronchial adenocarcinoma are involved less frequently than expected by chance. The significance of the tumour types implicated is discussed in relation to the possible pathogenesis.     

Pulmonary epithelial-myoepithelial carcinoma: a clinicopathologic and immunohistochemical study of 5 cases

Pulmonary epithelial-myoepithelial carcinomas are rare low-grade malignant neoplasms with histologic features similar to their salivary gland counterparts. We report a series of 5 cases and describe their clinical, morphological, and immunohistochemical features. The patients included 3 men and 2 women whose ages ranged from 38 to 56 years. All patients had obstructing endobronchial lesions that ranged from 2.5 to 5.0 cm in greatest dimension. The tumors were completely resected by simple lobectomy or pneumonectomy. In one patient, the tumor infiltrated perinodal soft tissue of a peribronchial lymph node with intranodal extension and metastasis within the same lymph node. The follow-up in these patients ranged from 4 to 12 months. The histologic appearance of these tumors varied, but all shared the common feature of a biphasic proliferation of epithelial (strong cytokeratin-positive; actin and S-100-negative) and myoepithelial (strong actin and S-100 and focal weak cytokeratin-positive) cells with formation of bilayered ductlike structures. The focal resemblance to other salivary gland-type tumors may cause diagnostic difficulties, particularly in small endobronchial biopsies. Although little is known about their biologic potential due to limited follow-up data, these tumors when in the lung clearly have the capacity to infiltrate and metastasize and therefore should be designated as epithelial-myoepithelial carcinoma. At present, it appears that treatment by complete surgical resection with negative margins alone is appropriate and adequate.     

Fine-needle aspiration cytological findings in five cases of epithelial-myoepithelial carcinoma of salivary glands

The cytologic features of five cases of epithelial-myoepithelial carcinoma arising in major salivary glands (four parotid and one submandibular gland) are presented. All cases were initially diagnosed as low-grade malignancies. The smears were generally cellular, with no specific architectural pattern. Single cells and naked nuclei were prominent in all cases. A biphasic epithelial (small-cell) and myoepithelial (large/clear-cell) pattern was identified readily in two cases and with difficulty in one case. The biphasic pattern may be subtle or absent since the clear cells have a fragile cytoplasm and often appear as naked nuclei. The differential diagnosis includes adenoid cystic carcinoma, polymorphous low-grade adenocarcinoma, and cellular pleomorphic adenoma.     

High-grade carcinoma component in epithelial-myoepithelial carcinoma of salivary glands clinicopathological, immunohistochemical and flow-cytometric study of three cases

 Three cases of epithelial-myoepithelial carcinoma (EMC) with coexisting areas of high grade carcinoma are reported. In two of the cases there was a previous recurrence, and in all three patients there had been a sudden increase in size before final surgery. The typical ductal and myoepithelial components of EMC showed the usual biphasic pattern and the expected immunophenotypes, with expression of wide spectrum cytokeratins, Cam 5.2 and EMA in the ductal part, and muscle-specific actin, smooth muscle actin, S-100 protein, vimentin and cytokeratins in the myoepithelial component. These areas also had a low mitotic count and low proliferation rate as measured by immunohistochemistry and by flow cytometry. Conversely, areas of high-grade tumour had the features of a large cell carcinoma, with focal mucin secretion in two cases. This high-grade component showed an epithelial immunophenotype in two cases, and was negative for all tested markers in the third one. The mitotic counts and the proliferation rates were much higher in these anaplastic areas. One of the patients died 3 months after treatment; another developed lymph node metastases 1 year later and was alive after 6 years of follow-up. The third patient was alive without evidence of disease 7 months after wide surgical resection of the tumour. The possibility of anaplastic transformation in EMC makes thorough sampling mandatory in this type of neoplasm. Received: 14 Octobre 1998 / Accepted: 7 December 1998     

Cytopathological features of an epithelial-myoepithelial carcinoma with predominant clear myoepithelial cells in the parotid gland

Epithelial-myoepithelial carcinoma (EMC) is a rare low-grade carcinoma occurring most frequently in the parotid gland. Most EMCs consist of two cell types that typically form double-layered ductal structures. However, occasionally EMC presents predominantly clear myoepithelial cells. A 34-year-old man visited in August 1993 and was diagnosed as having clear-cell carcinoma. The tumor was curatively resected. However, in the following 5 years, recurrence developed a total of five times. The imprint cytological feature of the recurrence at the third time showed monophasic clear cells in sheet clusters with overlapping. Most of the clear tumor cells presented an expression to alpha-smooth muscle actin (SMA). The imprint cytological feature of the recurrence at the fifth time showed increase of nuclear atypia with coarse chromatin patterns and large nucleoli. In addition to cytological findings, the cytological diagnosis of EMC with predominant clear myoepithelial cells requires a definite expression to SMA.     

Intercalated duct hyperplasia: possible relationship to epithelial-myoepithelial carcinoma and hybrid tumours of salivary gland

AIMS: The aims of this study were to ascertain the incidence of intercalated duct hyperplasia in association with cases of epithelial-myoepithelial carcinoma (EMC), and to explore a possible relationship between them and hybrid carcinomas of salivary glands. METHODS AND RESULTS: Seven cases of EMC with sufficient surrounding non-tumour parotid were examined. Three cases contained foci of intercalated duct hyperplasia adjacent to the tumour. One of the cases was a hybrid tumour composed of EMC and mucoepidermoid carcinoma. The hyperplastic intercalated ducts formed multiple foci within the salivary parenchyma and were composed of bland, uniform ducts. Cytological atypia was not identified. CONCLUSIONS: Intercalated duct hyperplasia may be a precursor lesion to EMC. Furthermore, it may also explain why EMC is frequently associated with other salivary gland carcinomas, so-called hybrid tumours, as well as sharing histological features with adenoid cystic carcinoma. Recognition of the latter is of particular importance because adenoid cystic carcinoma carries a poor prognosis.     

Sebaceous epithelial-myoepithelial carcinoma of the parotid gland: a case report of a new histologic variant

Epithelial-myoepithelial carcinoma (EMCa) is a double-cell layered low-grade malignant tumor, representing approximately 1% of all salivary gland tumors (Barnest et al. 2005 [1], Brocheriou et al. 1991 [2], Fonte et al. 2001 [3]). Its histologic characteristic is that of an inner layer of cuboidal epithelial cells with dense granular cytoplasm and central or basal rounded nucleus, and an outer layer of clear, polygonal myoepithelial cells, together forming ductal structures in a lobulated papillary or cystic pattern. Although solid components of clear cells are not uncommon, and squamous differentiation, spindle cells, and oncocytic appearance are well-documented histologic features of EMCa, sebaceous differentiation as a precise histologic variant has, to our knowledge, only been suggested by Shinozaki et al [4] in 2008. In this report, we present a case of a carcinoma of the parotid gland in a 59-year old female patient with an immunophenotype supporting the proposed entity of sebaceous EMCa.     

Bronchial mucoepidermoid carcinoma: apropos of 3 cases

We report three cases of bronchial mucoepidermoid carcinoma (BMEC) of low-grade malignancy with a relafase-free follow up. BMEC are rare tumors. The microscopic findings distinguish low-grade tumors which occur in children and young adults and high-grade tumors concerning older patients; this grading is based on the study of the epidermoid component. If possible, conservative therapy is appropriate in low-grade tumors. The prognosis of high-grade tumors is poor.     

Bronchial mucoepidermoid carcinoma after allogeneic bone marrow transplantation.

A 16 year old man underwent an allogeneic bone marrow transplantation (BMT) from an HLA identical sibling donor for acute lymphoblastic leukaemia in 1984. He developed chronic graft versus host disease involving the skin and kidneys. At day 400 after BMT his condition was complicated by obstructive airways disease, which was partially responsive to azathioprine and steroids. Five years after withdrawal of immunosuppressive treatment he developed dyspnoea and decreased pulmonary function test results, and steroid treatment was resumed. Fibrobronchoscopy revealed the presence of a mucoepidermoid carcinoma in the left main bronchus. After surgical laser resection, there was gradual clinical and functional improvement. There was no evidence of recurrence one year after surgery.     

Fine-needle sampling of salivary gland lesions VII. Cytology and histology correlation of five cases of epithelial-myoepithelial carcinoma

Fine-needle sampling (FNS) of five cases of epithelial-myoepithelial carcinoma, three primary tumors, and two local recurrences, was performed preoperatively in five patients. Cytologic diagnoses of malignancy were established in all tumors (three were reported as adenoid cystic carcinoma, two as adenocarcinoma not otherwise specified). Material for cytologic evaluation was satisfactory in all cases. Adenoid cystic carcinoma, polymorphous low-grade adenocarcinoma, papillary cystadenocarcinoma and cellular type of pleomorphic adenoma are the main differential diagnoses. Diagn. Cytopathol. 1998;19:405–409. © 1998 Wiley-Liss, Inc.