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

Hybrid Carcinoma of the Parotid Gland: An Extremely Rare Three Cases with an Immunohistochemical Analysis and a Review of the Literature

Salivary hybrid carcinoma (HC) is defined as when two or more kinds of carcinoma exist at the same location in a single mass. We reestimated and examined three cases of salivary gland HC. Case 1 involved a 76-year-old male. Case 2 involved a 74-year-old female. Case 3 involved a 66-year-old male. Histologically, case 1 involved a combination of salivary duct carcinoma (SDC) and squamous cell carcinoma (SqCC). Immunohistochemically, the former was positive for gross cystic disease fluid protein (GCDFP)-15 and androgen receptor (AR). Case 2 involved a combination of SqCC and neuroendocrine carcinoma. Immunohistochemically the latter was positive for synaptophysin and neural cell adhesion molecule (NCAM). Case 3 involved a combination of SDC and epithelial-myoepithelial carcinoma (EMC). Immunohistochemically, the former was positive for GCDFP-15 and AR, whereas the inner cells of the latter were positive for cytokeratin 7, and the outer cells of the latter were positive for actin. Because of the transitional zone between SDC and EMC, it was speculated that high-grade SDC arose from low-grade EMC.

MYB Translocation Status in Salivary Gland Epithelial-Myoepithelial Carcinoma: Evaluation of Classic, Variant, and Hybrid Forms

Epithelial-myoepithelial carcinoma (EMC) is a malignant salivary gland neoplasm comprised of a biphasic arrangement of inner luminal ductal cells and outer myoepithelial cells. Adenoid cystic carcinoma (AdCC) is also a biphasic tumor comprised of ductal and myoepithelial cells, but these components tend to be arranged in a more cribriform pattern. The occurrence of "hybrid carcinomas" that show mixed patterns of EMC and AdCC raises questions about the relationship of these morphologically overlapping but clinically distinct tumors. AdCCs frequently harbor MYB-NFIB gene fusions. Mapping of EMCs (including hybrid forms with an AdCC component) for this fusion could help clarify the true nature of EMC as a distinct entity or simply as some variant form of AdCC. Twenty-nine cases of EMC were evaluated including 15 classic low-grade EMCs, 7 intermediate-grade EMCs, 2 EMCs with myoepithelial anaplasia, 1 EMC with high-grade transformation, and 4 hybrid EMCs with an AdCC component. Break apart fluorescence in situ hybridization for MYB was performed, as was MYB immunohistochemistry. For the hybrid carcinomas and those with high-grade transformation, the divergent tumor components were separately analyzed. A MYB translocation was identified in 5 of 28 (18%) tumors including 3 of 4 (75%) hybrid carcinomas and 2 of 7 (29%) intermediate-grade EMCs. For the positive hybrid carcinomas, the fusion was detected in both the EMC and AdCC components. The MYB fusion was not detected in any of the classic EMCs (0/15) or in any of the EMCs with myoepithelial anaplasia (0/2) or high-grade transformation (0/1). The fluorescence in situ hybridization assay was unsuccessful in 1 case. MYB immunostaining was seen in 5 of 5 fusion-positive cases, and also 9 of 23 fusion-negative tumors. Classic low-grade EMCs are genetically distinct from AdCCs in that they do not harbor MYB fusions. The presence of a MYB fusion in EMCs showing hybrid features of AdCC or exhibiting highly infiltrative growth points to a subset of these tumors that may well be true AdCCs masquerading as EMCs.

More than meets the eye

We report an extremely rare case of a hybrid tumour of the maxillary sinus. A 51-year-old man presented with a 6-week history of nasal congestion and epiphora. Radiological imaging demonstrated a maxillary sinus tumour, with extensive local invasion. Surgical excision included maxillectomy, left eye exenteration and free flap closure. Histology of the excised specimen showed a rare hybrid tumour containing adenoid cystic carcinoma, salivary duct carcinoma, epithelial-myoepithelial carcinoma and basal cell adenoma. Hybrid tumours are very rare tumour entities which are composed of at least two distinct tumour types. Each tumour entity conforms with a defined tumour type. The tumour entities of a hybrid tumour are not separated but have an identical origin within a definite topographical area. Diagnosis and appropriate management requires high index of suspicion, pathological endeavour to look for a more aggressive accompanying tumour and adequate oncological treatment according to the highest grade of tumour.

Salivary gland hybrid tumour revisited: could they represent high-grade transformation in a low-grade neoplasm?

Salivary gland hybrid tumour, first described in 1996, is a very rare neoplasm for which exact morphological criteria have not been universally agreed upon. In contrast, the concept of high-grade transformation (HGT) in salivary neoplasms has been widely accepted during the last decade, and the number of reported cases is rapidly increasing. A review of the literature revealed 38 cases of hybrid tumour reported in 22 publications. During approximately the same time period, well over 100 cases of HGT in salivary neoplasms have been reported. There are important histological similarities between hybrid tumours and salivary tumours with HGT. In the latter, containing one tumour component of low-grade malignancy and the other of high grade, the two tumour components are not entirely separated and appear to originate in the same area. Virtually, all cases reported as hybrid tumour had no clear lines of demarcation between the two tumour types. We are inclined to suggest that most of the 38 cases of hybrid tumours described in the literature would today better be called tumour with HGT rather than hybrid tumour. The relative proportion of the two components may vary, and the high-grade component is sometimes very small, which emphasises the importance of very generous sampling of the surgical specimen. The molecular genetic mechanisms responsible for HGT, including what used to be called hybrid tumour, remain largely unknown. Abnormalities of a few genes (including p53, C-MYC, cyclin D1, HER-2/neu) have been documented. As insufficient data exist on gene abnormalities in these lesions, conclusions as to whether or not they have a common origin and which mechanisms are involved in transformation cannot be drawn. Due to the small number of cases reported, many of which lack follow-up details; indicators of prognosis of hybrid tumours are not available, but their behaviour seems to be similar to that of tumours with HGT, i.e. an accelerated aggressive course. HGT of salivary gland neoplasms greatly influences macroscopic and microscopic evaluation of the specimen but also, given the high incidence of metastases and morbidity, carries significant treatment implications.

Hybrid carcinoma of the larynx: a case report (adenoid cystic and adenocarcinoma) and review of the literature

Introduction. The nonsquamous carcinomas of the larynx are considered rare with the majority of malignant tumors in this area, reaching the rate of 95%, to be squamous cell neoplasms. Case Report. The case refers to a 53-year-old man that presented with symptomatology of motor nerve disease. During the evaluation of the neurologic disease, a subglottic mass of the larynx was revealed accidentally in the imaging examination. Under general anesthesia, we performed direct laryngoscopy and biopsy of the mass. The histopathologic examination revealed a hybrid carcinoma coexistence of two different carcinomas, an adenoid cystic carcinoma and an adenocarcinoma, not otherwise specified with poor differentiation. Regarding the therapeutic plan, the mass was considered inoperable due to its expansion to trachea and the patient received radiotherapy. Conclusions. Both the adenocarcinoma and adenoid cystic carcinoma are extremely rare types of malignant tumors in the larynx. The special interest of the present case is the coexistence of these two rare tumors in the same region of the larynx, being a hybrid tumor of the salivary glands in the larynx, which is the second reported case, based on our systematic literature review.

Sinonasal Adenoid Cystic Carcinoma

Objective

This study reviews the published outcomes related to sinonasal adenoid cystic carcinoma (SNACC). Clinical presentation, radiographic diagnosis, pathology, treatment, and management outcomes of this uncommon disease are reported.

Data Sources

PubMed database.

Methods

A systematic review of studies for SNACC from 1960 to 2012 was conducted. A PubMed search for articles related to SNACC, along with bibliographies of those articles, was performed. Articles were examined for both individual patient data (IPD) and aggregate patient data (APD) that reported survivability. Demographics, disease site and spread, treatment strategies, follow-up, outcome, and survival were described for IPD, and a meta-analysis for survival rates was performed for APD.

Results

A total of 55 journal articles were included. Individual patient data were reported in 39 journal articles, comprising a total of 88 cases of SNACC. Sixteen articles, totaling 366 patients that reported aggregate 5-year survivorship pertaining to SNACC, were also included. Average follow-up in the IPD was 51.2 months (range, 1-198 months), and 5-year survivorship was 63.5%. In the studies reviewed, surgery followed by postoperative radiotherapy was the most common therapy used and resulted in the highest percentage of survivors. Aggregate patient data meta-analysis revealed a 5-year survival rate of 62.5%.

Conclusion

This study contains the largest pool of SNACC patients to date. The data suggest that SNACC has a poor overall prognosis. It also suggests that surgery with postoperative radiotherapy is the most commonly used and may possibly be the most effective therapy.

Lacrimal gland adenoid cystic carcinoma with high-grade transformation to myoepithelial carcinoma: report of a case and review of literature

Adenoid cystic carcinoma (AdCC) is the most frequent malignant neoplasm of the lacrimal glands. Like its salivary gland counterpart, lacrimal AdCC can rarely undergo high-grade transformation ("dedifferentiation"). We herein report the clinical, radiographic and microscopic findings of a lacrimal gland AdCC with high grade transformation, occurring in a 39-year-old female patient. In contrast to salivary gland AdCC with high-grade transformation, which usually shows a high grade component with "ductal" differentiation, in the case presented, the "dedifferentiated" component showed morphologic and immunohistochemical features of myoepithelial differentiation.

Epitheiial-Myoepithelial Carcinoma (EMC): Uncommon tumor with rare presentation, importance of immunohistochemistry for the diagnosis

Epithelial myoepithelial carcinomas (EMC) are rare carcinomas of the salivary glands. We report here the 6th case of this tumor which arises at the nasal cavity. In case of any histopathological report shows up a pleomorphic adenoma in an unusual site, we highly recommended the use of immunohistochemistry assay as an important tool for the diagnosis of this tumor.

Primary malignant myoepithelioma of the left maxillary sinus: a case report

We describe the case of a 41-year-old woman who presented with a malignant myoepithelioma (MME) in her left maxillary sinus. Exploratory biopsy of the left maxillary sinus was performed and pathological examination demonstrated that the tumour was positive for calponin and cytokeratin 14, which are indicative of MME. Lateral rhinotomy and left total maxillectomy were undertaken and the patient received radiotherapy and chemotherapy post-surgery. Primary recurrence and metastasis to the left angle of the mandible occurred 9 months after the surgery. The patient died of cachexia 13 months after the surgery.

Epithelial-myoepithelial carcinoma: a review of the clinicopathologic spectrum and immunophenotypic characteristics in 61 tumors of the salivary glands and upper aerodigestive tract

To further define the clinicopathologic spectrum of epithelial-myoepithelial carcinoma (EMCa), we report the gross, histologic, and immunophenotypic characteristics of 61 tumors seen within a 30-year-period. The mean age at presentation was 60.9 years, with a female predominance (1.5:1). The most common sites were parotid (62.1%), sinonasal mucoserous glands (10.3%), palate (8.6%), and submandibular (8.6%). Most EMCas showed a characteristic nodular/multinodular growth pattern and classic biphasic tubular histology. However, new morphologies in EMCa such as ancient change (8.2%), "Verocay"-like change (3.3%), and sebaceous differentiation (13.1%) were noted. Specific histologic variants were dedifferentiated EMCa (3.3%), oncocytic EMCa (8.2%), EMCa ex pleomorphic adenoma (1.6%), double-clear EMCa (3.3%), and EMCa with myoepithelial anaplasia (3.3%). All cytokeratin cocktails selectively highlighted the epithelial component well. Of the myoepithelial markers, p63, smooth muscle actin and vimentin performed best. Bcl-2 and c-kit were frequently positive (66.7% and 69.2%, respectively). p53 was highly expressed only in 1 dedifferentiated EMCa. The recurrence rate was 36.3% (median disease-free survival 11.34 y), but death was rare with 5-year and 10-year disease-specific survivals of 93.5% and 81.8%, respectively. The most important univariate predictors of recurrence were margin status (log rank P=0.006), angiolymphatic invasion (P=0.002), tumor necrosis (P=0.004), and myoepithelial anaplasia (P=0.038). Thus, EMCa is generally a low-grade tumor with a broader morphologic spectrum than previously thought, with several key features predictive of recurrence. Immunohistochemistry can aid diagnosis by highlighting the biphasic nature of the tumor.