A HIGH-GRADE MALIGNANCY BRONCHIAL MUCOEPIDERMOID CARCINOMA WITH FEATURES OF GIANT CELL CARCINOMA

A high-grade mucoepidermoid carcinoma associated with giant cell carcinoma of the bronchus was found in a 41-year-old man. Light and electron microscopic examinations showed glandular and squamous elements. The histology of the giant cell carcinoma was similar to those of previously reported giant cell carcinomas. It was assumed that the giant cell carcinoma in the present case is the result of transformation of mucoepidermoid carcinoma originating in the bronchial gland.     

Mucoepidermoid carcinoma of palatinal glands with exuberant foreign-body giant cell reaction

A 69-year-old man with a 0.6cm yellowish polypoid lesion in the lateral soft palate for 2 years is presented. Histological examination of the tumor revealed a small, well-differentiated, mucoepidermoid carcinoma dominated by densely packed cholesterol clefts in association with an exuberant foreign-body reaction with several giant cells. The tumor entity 'mucoepidermoid carcinoma with foreign-body giant cells' might be differentiated from 'mucoepidermoid carcinoma with an osteoclast-like giant cell stromal reaction' because differences in pathogenesis and tumor behavior are assumed.     

颈部淋巴结黏液表皮样癌

目的 探讨颈部淋巴结黏液表皮样癌的临床病理特点及鉴别诊断.方法 对1例颈部淋巴结黏液表皮样癌的临床病理特点进行分析并复习文献.结果 患者3次入院手术病理检查组织形态有较大变化.第一次活检标本镜下见淋巴结包膜完整,结内肿瘤组织主要由3种细胞构成:黏液细胞、中间型细胞及表皮样细胞,并可见较多含黏液的囊腔结构.第二次见肿瘤仍位于淋巴结内,主要由表皮样细胞构成,偶见分泌黏液的细胞,含黏液的囊腔结构几乎全部消失.第三次活检标本见横纹肌内浸润的癌细胞巢主要由表皮样细胞构成.随访2年,未见其他部位肿瘤.结论 (1)颈部淋巴结可能会发生原发性的涎腺黏液表皮样癌.(2)颈部淋巴结的黏液表皮样癌可反复复发并发生结外浸润.(3)随着病变进展和(或)复发,黏液表皮样癌的分化程度会逐渐降低,组织病理学形态会发生相应改变.     

Mucoepidermoid carcinoma arising in Warthin's tumor of the parotid gland

Malignant transformation of Warthin's tumor is extremely rare, although it is the second most common benign tumor of the parotid gland. We describe our experience of mucoepidermoid carcinoma arising in Warthin's tumor of the parotid gland in a 64-year-old man. He had a swelling in the left parotid-masseteric region. The removed tumor was well encapsulated and histopathologically comprised Warthin's tumor and low-grade mucoepidermoid carcinoma. The mucoepidermoid carcinoma infiltrated lymphoid stroma of the Warthin's tumor, but capsular invasion is not found. Considering the clinical course and physical examination, the lesion was diagnosed as mucoepidermoid carcinoma arising in Warthin's tumor because its features filled the criteria of malignant transformation of Warthin's tumor. There has been no recurrence or distant metastasis for 19 months. Histological change from Warthin's tumor to mucoepidermoid carcinoma may be implicated in squamous or goblet cell metaplasia of epithelial cells. It is considered that the neoplastic cells of Warthin's tumor acquire malignant genotypes simultaneously with this dual differentiation.     

Sclerosing mucoepidermoid carcinoma with eosinophilia of the salivary glands

We encountered two cases of low malignant mucoepidermoid carcinoma with scanty cellular atypism which originated in the parotid or submandibular gland and was characterized by marked fibrosis and eosinophilic infiltration within tumor tissue despite the predominance of the squamous component. Here we report these two cases and provide a review of the literature. We believe that clinically these two tumors with stromal fibrosis and eosinophilic infiltration have a low malignant potential, although histological examination revealed a scanty mucus-producing epithelial component. Therefore, we consider this type of tumor as a new subtype of mucoepidermoid carcinoma. A low-malignant mucoepidermoid carcinoma with stromal fibrosis and eosinophilic infiltration, as described in these two cases, may be misdiagnosed as a highly malignant mucoepidermoid carcinoma or squamous cell carcinoma because of its histologically scanty mucus-producing epithelial component. The objective of this study was to clarify their differences and to discuss the rendering of an accurate histological diagnosis, the degree of malignancy in relation to prognosis prediction, and the choice of therapy. In addition, we propose regarding this type of tumor as a new subtype of mucoepidermoid carcinoma.     

Mucoepidermoid carcinoma arising in the glans penis

Mixed carcinoma (squamous and glandular) of the penis is a rare neoplasm with an unknown origin and a poorly defined prognosis. The mucoepidermoid carcinoma described herein has not been previously reported to our knowledge. The present carcinoma arose from and extensively ulcerated the squamous epithelium of the glans penis, including that surrounding the urethral meatus. The neoplasm was composed of well-differentiated nonkeratinizing squamous cell carcinoma associated with large areas of carcinoma formed by cell nests that contained poorly differentiated squamous elements and large eosinophilic to pale granular cells. Mucin stains revealed approximately one quarter of the pale cells contained mucous substances. These findings are virtually identical to the mucoepidermoid type of carcinoma seen in the cervix. The 3 previously reported cases of adenosquamous carcinoma of the penis demonstrated a relatively indolent course, with only one being associated with a single inguinal lymph node metastasis. That patient was alive and well 9 years following diagnosis. Our example of mucoepidermoid carcinoma appears to demonstrate a more aggressive course than those reported previously.     

Thyroid sclerosing mucoepidermoid carcinoma with eosinophilia: mimic of Hodgkin disease in nodal metastases

We present the clinical and pathologic findings of a case of sclerosing mucoepidermoid carcinoma with eosinophilia of the thyroid in a 39-year-old woman. This particular case is notable because it initially presented as a cervical lymph node metastasis, and the initial clinical and histologic impression was Hodgkin disease, nodular sclerosis type. Sclerosing mucoepidermoid carcinoma with eosinophilia is a differentiated malignant neoplasm of the thyroid that can be confused with anaplastic carcinoma, medullary carcinoma, squamous cell carcinoma, or, as in this case, Hodgkin disease. A correct diagnosis of sclerosing mucoepidermoid carcinoma with eosinophilia involves awareness of this entity and appropriate immunohistochemical analysis. In this article, we briefly review the literature and stress the histologic and cytologic findings characteristic of sclerosing mucoepidermoid with eosinophilia of the thyroid.     

Special types of thyroid carcinoma

This article reviews the small percentage of thyroid tumours that are not classified as classic papillary thyroid carcinoma, follicular thyroid carcinoma, and medullary thyroid carcinoma. It includes subtypes of papillary thyroid carcinoma, including, tall‐cell, hobnail/micropapillary, columnar cell, diffuse sclerosing and solid variants. Poorly differentiated carcinoma, high‐grade carcinoma and anaplastic thyroid carcinoma are reviewed. Also discussed are entities that are unusual but need to be recognized as primary thyroid neoplasms, i.e. mucoepidermoid carcinoma, sclerosing mucoepidermoid carcinoma with eosinophilia, and mammary analogue secretory carcinoma/secretory carcinoma. The pathological features and prognostic factors are described; a brief review of molecular correlates of these neoplasms is included.     

Primary undifferentiated small cell carcinoma of the esophagus

We histologically examined undifferentiated small cell carcinoma of the esophagus from 21 patients and used immunohistochemical methods for detection of chromogranin A and p53, bcl-2, and Rb oncoproteins. Nine (43%) of the 21 carcinomas consisted solely of undifferentiated cells, but heterogeneous components of in situ or invasive squamous cell carcinoma or mucoepidermoid carcinoma were observed in the other 12 (57%) tumors. Squamous cell carcinoma in situ was observed in the mucosa adjacent to the main tumor in 7 (50%) of the 14 resected esophageal specimens. An admixture of invasive squamous cell carcinoma and undifferentiated carcinoma was observed in 4 (19%) of the 21 tumors, and mucoepidermoid carcinoma was noted in one case. Chromogranin A staining yielded a positive reaction in two (10%) undifferentiated components but was negative in all heterogeneous components. Multiple sites of p53 immunopositivity were seen in the undifferentiated component of 17 (81%) of the 21 tumors, as well as in the in situ or invasive squamous cell carcinoma or mucoepidermoid carcinoma components of 9 (75%) of 12 tumors. Seven (33%) of the 21 tumors showed positive bcl-2 immunoreactivity in the small cell component, but all of the heterogeneous components were negative. Rb protein immunoreactivity was observed in the small cell component of one (5%) case and in 9 (75%) of the 12 heterogeneous components. Six (86%) of the seven in situ squamous cell carcinoma components were positive for Rb protein. Eighteen (86%) of the 21 patients died within 24 months of diagnosis. Two patients (10%) who survived for more than 24 months had received chemotherapy.     

Comparative histogenesis and morphogenesis of mucoepidermoid carcinoma and pleomorphic adenoma

Summary Current classifications of salivary gland tumors separate mucoepidermoid carcinoma from other neoplasms on the basis of a number of histological features, in particular the lack of participation of neoplastic myoepithelial cells. However, ultrastructural examination of low- and intermediate-grade mucoepidermoid carcinomas and pleomorphic adenomas reveals many common organizational and cellular features. Of prime importance is the relationship of intermediate cells to the luminal cells in mucoepidermoid carcinomas, which is remarkably similar to that seen between modified myoepithelial cells and luminal cells in pleomorphic adenomas. The results suggest that intermediate cells of mucoepidermoid carcinoma are the counterpart of the modified myoepithelial cells of pleomorphic adenoma. The generally accepted hypothesis that the former tumor develops from an excretory duct reserve cell, while the latter originates from an intercalated duct stem cell does not seem to be valid; pleomorphic adenoma and mucoepidermoid carcinoma appear to be closely related morphologically.     

Clear cell mucoepidermoid carcinoma of the parotid gland: a case report

Clear cell variant of mucoepidermoid carcinoma of the salivary glands is rare. A 55-year-old male patient with recently growing left parotid mass underwent superficial parotidectomy. Although the dominant component of the tumor was composed of clear cells, mucin containing cells were also present. Histochemically, alcian blue stain supported intracellular mucin positivity. Immunohistochemically, p63 was positive. Based on the morphological, histochemical and immunohistochemical findings, the case was diagnosed as mucoepidermoid carcinoma, clear cell variant.     

Composite follicular variant of papillary carcinoma and mucoepidermoid carcinoma of thyroid gland: a case report

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.     

Diffuse pagetoid squamous cell carcinoma of the esophagus combined with choriocarcinoma and mucoepidermoid carcinoma: an autopsy case report

Esophageal squamous cell carcinoma in situ (SCCIS) with diffuse pagetoid features is a recently recognized rare variant of squamous cell carcinoma. A histopathological study of a specimen from a 70-year-old male Japanese patient is reported. The patient died of respiratory failure due to rapidly progressing metastatic pulmonary tumors of unknown origin 73 days after the onset of hemosputum. Autopsy disclosed widespread metastasis of choriocarcinoma in the absence of tumors of the testes or other common sites of germ cell tumors. Elevation of human chorionic gonadotropin (hCG-beta) levels was later detected in the stored serum. Serial histological evaluation of the entire esophagus revealed a small primary site of choriocarcinoma in a background of diffuse SCCIS, mainly of pagetoid type, accompanied by several small foci of submucosally invasive squamous cell carcinoma and primary mucoepidermoid carcinoma. These stimulated nodal metastasis independently of the choriocarcinoma. The SCCIS did not alter the gross mucosal appearance. This is the first reported case of diffuse pagetoid SCCIS combined with choriocarcinoma. Morphological findings and previous studies suggest that the extensive SCCIS of the esophagus resulted from pagetoid spread of tumor cells. The invasive squamous cell carcinoma, mucoepidermoid carcinoma and choriocarcinoma are suggested to have originated from the overlying SCCIS.     

Mucoepidermoid carcinoma of the oral cavity

There is presently no uniformly accepted grading system for mucoepidermoid carcinoma, largely due to a lack of consensus as to what criteria should be used to formulate histological grades. The present study was undertaken to determine the relationship between histological grade, clinical stage and survival in these neoplasms. Clinical and histological data from 34 patients with mucoepidermoid carcinoma were reviewed. Mucoepidermoid carcinoma was most common in the parotid gland (44.1%), while 25% of patients had tumors in the minor salivary glands. Low, intermediate, and high-grade neoplasms accounted for 61.7%, 26.5%, and 11.8% of tumors, respectively. There was a general trend towards increasing clinical aggressiveness with increasing histological grade. Similarly, postoperative tumor recurrences were marginally more common in high-grade than in low-grade mucoepidermoid carcinomas. However, both of these findings were statistically insignificant, mainly due to small sample size, late clinical presentation, poor clinical follow-up, incomplete management and incomplete records. These factors explain the relatively low survival figures in the present study, as compared to higher survival figures in white patients with mucoepidermoid carcinoma.     

Mucoepidermoid carcinoma of the thyroid

Clinical and morphological features of three cases of primary mucoepidermoid carcinoma of the thyroid are described. The tumours were composed of two cell types. One of these resembled squamous epithelium and ultrastructurally showed tonofilaments and numerous desmosomes. The other cell type contained Alcian blue and mucicarmine positive mucin and, on electron microscopy, showed mucigen granules. Marked stromal fibrosis and psammoma bodies were seen in all tumours. Immunohistochemical studies showed that the tumour cells were negative for thyroglobulin. A few calcitonin-containing cells were seen in one metastatic tumour. One tumour showed, in addition to the histological features of mucoepidermoid carcinoma, anaplastic areas with obvious transition between the two histological patterns. The same thyroid also had a small thyroglobulin-positive papillary carcinoma in the opposite lobe. All tumours presented lymph node metastases. In two cases the primary tumour was confined within the thyroid capsule but that with anaplastic areas invaded surrounding structures. This patient died 13 months after diagnosis; the other patients are alive and symptomless one and 10 years since diagnosis. Mucoepidermoid carcinoma of the thyroid appears to be a clinicopathological entity that resembles papillary carcinoma in its natural history. The origin of the tumour is unclear. There is, however, some histological and immunohistological data suggesting that the tumour might be related to the ultimobranchial system although some histological features also appear to favour a common origin with papillary carcinoma.     

Esophageal pleomorphic giant cell carcinoma combined with small cell carcinoma

Herein is presented the case of an esophageal pleomorphic giant cell carcinoma combined with small cell carcinoma (SCC). The patient, a 77-year-old man, initially presented with dysphagia and hoarseness, and endoscopy indicated a large esophageal tumor. Despite chemoradiation therapy, the patient died from widespread local extension of the tumor and distant metastases approximately 8 months after onset of the symptoms. Histologically, the primary tumor was composed of pleomorphic tumor components, SCC components, and a tiny focus of squamous cell carcinoma. The pleomorphic tumor cells, consisting of solid sheets of poorly cohesive epithelioid cells and numerous multinucleated giant cells with abundant eosinophilic cytoplasm, were immunohistochemically positive for vimentin and desmin, with scattered positivity for epithelial membrane antigen (EMA) and neuron-specific enolase (NSE), but negative for myoglobin. These findings were histopathologically compatible with pleomorphic giant cell carcinoma occurring at other sites such as the lung. SCC cells, morphologically similar to their pulmonary counterpart, were positive for EMA and some neuroendocrine markers such as chromogranin A and NSE, and occasionally positive for vimentin and desmin. Esophageal pleomorphic giant cell carcinoma can occur in close association with SCC, and should be included in the differential diagnosis of esophageal tumors showing pleomorphism.     

Primary pulmonary mucoepidermoid carcinoma: Cyto-histologic correlation and review of the literature

Preoperative fine needle aspiration diagnosis and cyto-histologic correlation of primary pulmonary mucoepidermoid carcinoma have rarely been described in detail in the literature. A 26-year old male presented at our institution with cough, bloody sputum, and a 4.3 cm left lower lobe lung mass. He was accurately diagnosed with pulmonary mucoepidermoid carcinoma on preoperative aspiration cytology. The patient subsequently proceeded to left lower lobectomy, confirming the diagnosis. In this article, we present a detailed report of primary pulmonary mucoepidermoid carcinoma describing the cytologic and histologic morphologic features, its differential diagnosis with review of the literature.     

Pulmonary granular cell tumor coexisting with bronchogenic carcinoma

Pulmonary granular cell tumors (GCTs) are uncommon and predominantly benign. The coexistence of GCTs with bronchogenic carcinoma is rare. We report three cases of GCT occurring simultaneously with a primary bronchogenic carcinoma. In one case mucoepidermoid carcinoma was seen colliding with a bronchial submucosal GCT. In another case an endobronchial GCT was seen beneath squamous cell carcinoma in situ and adjacent to invasive squamous carcinoma. In the third case a central bronchial GCT was identified concurrently with a peripheral adenocarcinoma. We suggest that the presence of a GCT should prompt adequate sampling to rule out the coexistence of bronchogenic carcinoma. Clinical awareness and complete evaluation for a malignant primary lung tumor will lead to more appropriate therapy. Ann Diagn Pathol 5:74-79, 2001.     

Invasive breast carcinoma with features of neuroendocrine carcinoma and carcinoma with osteoclastic cells: fine-needle aspiration cytology and histology of two cases

We report two cases, with overlapping cyto-histological characteristics, of invasive neuroendocrine carcinoma of the breast with associated stromal features distinctive of carcinoma with osteoclastic giant cells. Fine-needle aspiration cytology showed monomorphic, medium-sized, mildly atypical neoplastic cells, with interspersed multinucleated giant cells and lympho-histiocytic components; hemosiderin deposits were also appreciable. Macroscopic features were typical of invasive carcinoma, but with unusual brown staining. Light microscopy revealed moderately differentiated invasive carcinoma mainly composed of solid sheets of round to polygonal medium-sized cells with a tendency to produce peripheral palisading (carcinoid-like morphology); osteoclast-like multinucleated giant cells, lymphocytes and histiocytes were dispersed only among tumour cells in the distinctive stroma of the carcinoma with osteoclastic giant cells; this stroma was characterised by reactive/fibroblastic features, hypervascularization, extravasated blood cells and hemosiderin deposits that gave rise to the typical staining seen macroscopically. Immunohistochemically, cancer cells were diffusely positive for the neuroendocrine marker synaptophisin with partial chromogranin and NSE staining; the ostoclastic giant cell and histiocyte component were strongly positive for CD68. Both cases also had lymph node metastases; the epithelial neoplastic cells, with regards to neuroendocrine markers, were overlapping to the primitive tumour, the histiocytic/giant cell component appeared present, although with a lower degree, while the distinctive stroma was absent. Breast neuroendocrine carcinomas, associated with multinucleated giant cells and stroma typical of the carcinoma with osteoclastic-like cells, to our knowledge, have not been reported.