Epithelial myoepitheial carcinoma of minor salivary gland--low grade malignant tumor presenting with nodal metastasis

Epithelial myoepithelial carcinoma (EMC) is a rare low grade malignant salivary gland neoplasm that most commonly occurs in the parotid gland but can also arise in minor salivary glands. We report a case of primary epithelial myoepithelial carcinoma of minor salivary gland in a 25 year old women who presented with swelling left cheek of one year duration and bilateral submandibular lymphadenopathy. A mass causing erosion of mandible, thyroid cartilage and masseter muscle was identified on CT scan. This was excised and histological examination revealed a mixture of ductal structures consisting of inner dark cells and outer clear cells seen in solid sheets. Immunohistochemical analysis showed the clear cells to be weakly positive for S100 and smooth muscle actin (SMA) and ductal cells to be positive for cytokeratin (CK) and epithelial membrane antigen (EMA). The characteristic morphological and immunohistochemical features aided in the diagnosis of epithelial myoepithelial carcinoma.     

Pleomorphic carcinoma of the breast with expression of macrophage markers: report of two cases

Pleomorphic ductal carcinoma of the breast is a rare variant included in the morphological group of infiltrating ductal carcinoma. The pleomorphic carcinoma is composed predominantly of epithelial and multinucleated tumor giant cells. We report here two cases presenting a lesion composed microscopically of a proliferation of large pleomorphic cells with a predominance of multinucleated giant cells. These lesions were negative for estrogen receptor, progesterone receptor and Her2-neu (triple-negative phenotype). Basal markers (cytokeratin 5/6, cytokeratin 17 and epidermal growth factor receptor [EGFR]) were present, accompanied by the presence of histiocyte marker CD163 in most neoplastic giant cells. High-grade pleomorphic breast carcinomas with the triple-negative phenotype and expression of basal markers might be included in the basal subtype. This is the first report about the co-expression of macrophage marker CD163, with tumor (P53) or epithelial markers (CAM5.2), as indicated by double immunohistochemistry in pleomorphic ductal carcinoma of the breast.     

Clear cell papulosis of the skin: a case report from Singapore

Clear cell papulosis of the skin is a rare condition; to our knowledge only 12 cases have been reported. Here, we report for the first time a case of clear cell papulosis with cytokeratin 7 expression and provide a comprehensive literature review. A 16-month-old girl presented with 3 hypopigmented lesions in the pubic region that were 3 to 9 mm in diameter; 1 lesion was papular, and the other 2 were macular. A skin biopsy revealed acanthosis with a proliferation of clear cells along the basal and suprabasal layers of the epidermis occurring in small clusters and singly. The cells had round to oval regular nuclei with abundant to moderate lightly eosinophilic to clear cytoplasm and intracytoplasmic mucin. Immunostaining produced positive results for carcinoembryonic antigen, AE1/3, epithelial membrane antigen, cell adhesion molecule 5.2, and cytokeratin 7 and negative results for gross cystic fluid disease protein, S100, and HMB-45. Clear cells of clear cell papulosis are mucin-positive and S100-negative glandular-secretory epithelial cells with histogenetic features of Toker cells of nipple and Paget cells. Immunohistochemical features support an eccrine secretory cell origin because the clear cells are consistently and strongly positive for carcinoembryonic antigen, positive for cell adhesion molecule 5.2, and negative or rarely positive for gross cystic fluid disease protein.     

Collecting-duct carcinoma of the kidney with prominent signet ring cell features.

We report a case in a 74-year-old woman of collecting-duct carcinoma of the kidney with prominent signet ring cell features. Grossly, the tumor measured 5.5 cm in greatest dimension, occupied the entire upper pole of the kidney, and was well circumscribed. Microscopically, it displayed a predominant tubulopapillary pattern of growth with a hyalinizing stroma. The tumor tubules were lined by a single layer of cells with large, pleomorphic nuclei, some of which had a hobnail appearance. Large intracytoplasmic vacuoles with compression of nuclei (signet ring cells) were present throughout the tumor. Alcian blue, mucicarmine, and periodic acid-Schiff stains failed to identify intracellular mucin or glycogen in the signet ring cells. Enlarged cells with intracytoplasmic vacuoles were also noted in the adjacent collecting ducts. The tumor cells were immunohistochemically positive for cytokeratin including cytokeratin 7, CAM 5.2, AE1/3, and 34 beta E12, vimentin, peanut lectin agglutinin, and Ulex europaeus agglutinin. Electron microscopy revealed that the intracytoplasmic vacuoles were due to intracellular edema. To the best of our knowledge, this is the first reported case of renal collecting-duct carcinoma with prominent signet ring cell features.     

Adenoma of the esophagus with intracytoplasmic mucoid bodies

We report a tubular adenoma of the esophagus in a 79-year-old man. The tumour had progressed to an intramucosal carcinoma at follow-up 6 months later. The adenoma displayed a peculiar and heterogeneous histological picture with non-dysplastic and cystic areas alternating with those of a typical tubular adenoma. The tumour revealed a strong and diffuse expression of cytokeratin 7 and basal cell cytokeratin, whereas cytokeratin 20 was focally positive only. The most remarkable finding, however, was the demonstration of intracytoplasmic inclusion-like mucoid bodies of the epithelial cells in a small area of the adenomatous component. These inclusions stained PAS positive and alcian blue negative, and electron microscopy revealed a homogeneous structure without viral-like particles.     

Sarcomatoid carcinoma of the pancreas: A case report with immunohistochemical study

Sarcomatoid carcinoma of the pancreas is an uncommon neoplasm. The immunohistochemical characteristics of this unique type of pancreatic tumor were studied. Histologically, there was diffuse proliferation of atypical spindle cells that had hyperchromatic, short, spindle-shaped nuclei and pale cytoplasm. A few tiny foci of small tubular structures were seen in connection with the atypical spindle-shaped cells. Immunohistochemical examination showed that the spindle cells were positive for epithelial cell markers (cytokeratin AE3, cytokeratin AE1, epithelial membrane antigen) and DF3 (MUC1 apomucin-related antigen (ARA)), and were negative for markers such as vimentin, desmin, neuron-specific enolase, and myoglobin. DF3 antigen is known to be expressed in invasive ductal carcinoma of the pancreas and liver, as well as of the breast. Other MUC1-ARA (MY.1E12, MUC1 glycoprotein, HMFG-1, HMFG-2) and anti-CA19-9 were also detected in the present case. Thus, this tumor was diagnosed as anaplastic carcinoma (sarcomatoid carcinoma).     

Immunohistochemical characterization of pancreatic tumors induced by dimethylbenzanthracene in rats

Dimethylbenzanthracene (DMBA) induces pancreatic adenocarcinomas in rats 9 months after carcinogen exposure, with precursor lesions (tubular complexes) developing 1 month after initiation of treatment. Because previous studies have suggested an acinar cell of origin for these tumors, we investigated the expression pattern of ductal, acinar, and islet cell markers in these cancers to gain insight into their phenotype and cell of origin. Pancreatic neoplasms were induced in rats by implantation of DMBA into the head of the pancreas. Lesions studied included 10 early tubular complexes (DMBA for 2 weeks), 8 tubular complexes (DMBA for 1 month), and 10 adenocarcinomas (DMBA for 9 months). Normal rat pancreas served as a control. For comparison, 5 human ductal adenocarcinomas were also evaluated. Immunohistochemistry with ductal (keratin, cytokeratin 19, cytokeratin 20), acinar (chymotrypsin), and islet (chromogranin A) cell markers was performed to analyze the tissues. Rat tubular complexes and adenocarcinomas revealed strong expression of keratin, cytokeratin 19, and cytokeratin 20 in the cytoplasm of all neoplastic cells, absence of chymotrypsin, and rare immunoreactivity to chromogranin A. Human adenocarcinomas showed strong expression of keratin and cytokeratin 19 in all neoplastic cells, expression of cytokeratin 20 in 5-20% of cells, and absence of chymotrypsin and chromogranin A. Pancreatic adenocarcinomas induced by DMBA in rats express markers consistent with a ductal phenotype, as observed in human tumors. Ductal marker expression in early tumor stages suggests a ductal cell of origin.     

Sebaceous carcinoma of the parotid gland

Summary Sebaceous carcinoma of salivary gland origin is extremely rare and, because of its rarity, the clinicopathological characteristics and the histogenesis are not fully understood. We present a case of sebaceous carcinoma of the parotid gland which brings the total number of reported cases to 22.The tumor showed epithelial cell nests which were mainly composed of sebaceous cells with marked cellular atypia. In most of the nests, glandular spaces lined by ductal epithelium were present. Scattered mucous cells and flattened eosinophilic cells at the periphery of the nests were also seen. Ultrastructural and immunohistochemical observations of the tumour revealed coexistence of sebaceous and glandular differentiations in some tumour cells. Tumour cells with lipid granules often participated in the formation of glandular structures or exhibited intracytoplasmic lumina, and immunohistochemical localization of lactoferrin and secretory component, the functional markers of ductal epithelium of salivary gland, was demonstrated not only in duct-forming tumour cells but also in many sebaceous tumour cells.It seems likely that sebaceous carcinoma originates from pluripotential duct cells which can differentiate into sebaceous, ductal and mucous cells.     

The majority of triple-negative breast cancer may correspond to basal-like carcinoma,but triple-negative breast cancer is not identical to basal-like carcinoma

Recently, the concept of basal-like carcinoma has been proposed. However, there are only a few reports about the relationship between triple-negative cancer and basal-like carcinoma. In this article, we report the study of the expression of basal cell markers in 11 triple-negative cancers. Eight tumors (4 metaplastic carcinomas, 2 invasive ductal carcinomas, 1 invasive papillary carcinoma, and 1 medullary carcinoma) were positive for more than three markers among cytokeratins 5, 14, and 17, and p63. Three tumors (2 invasive ductal carcinomas and 1 apocrine carcinoma) were completely negative for all markers. Among 8 tumors positive for basal markers, cytokeratins 5 and 17 were expressed in all 8 tumors, cytokeratin 14 in 6 tumors, and p63 in 7 tumors. Finally, we conclude that the majority of triple-negative cancer may correspond to basal-like carcinoma, but the two entities are not identical. The use of combination immunohistochemistry including cytokeratins 5, 14, and 17 and p63 may contribute to the detection of basal-like carcinoma.     

Solid papillary ductal carcinoma in situ versus usual ductal hyperplasia in the breast: a potentially difficult distinction resolved by cytokeratin 5/6

The solid papillary variant of ductal carcinoma in situ is an uncommon entity, which usually presents in the seventh or eighth decade and may be associated with invasive mucinous carcinoma. Solid papillary ductal carcinoma in situ (SP-DCIS) shares many morphological features with usual ductal hyperplasia (UDH) involving a papilloma: papillary architecture, solid growth, cellular streaming, and low-grade nuclear features. These similarities can make the distinction between these 2 entities challenging. Recent studies have demonstrated that immunohistochemical staining for cytokeratin 5/6 can distinguish UDH from conventional forms of ductal carcinoma in situ. Most of the epithelial cells of UDH express cytokeratin 5/6, but the tumor cells of ductal carcinoma in situ do not. We tested the hypothesis that the results of staining for cytokeratin 5/6 can distinguish UDH from the solid papillary variant of ductal carcinoma in situ. Immunohistochemical staining of 14 cases of SP-DCIS and 9 cases of UDH (4 involving papillomas) was performed using cytokeratin 5/6 antibody clone D5/16 B4. Strong cytoplasmic or membrane staining was considered positive. The hyperplastic cells in all cases of UDH showed strong staining for cytokeratin 5/6. The percentage of positive cells ranged from 50% to 80%. None of the SP-DCIS tumor cells stained for cytokeratin 5/6; however, many cases did show staining of occasional entrapped, benign epithelial, and myoepithelial cells. We conclude that the absence of strong cytokeratin 5/6 expression by SP-DCIS distinguishes it from its morphological mimic, UDH. Pathologists must guard against misinterpreting SP-DCIS as UDH in those cases in which the carcinoma cells engulf cytokeratin 5/6-expressing residual, native epithelial cells.     

Acantholytic squamous cell carcinoma in a cow

A subcutaneous mass in the perineal area of a female Holstein cow underwent histo-pathological evaluation. Microscopically, this lesion revealed a prominent alveolar pattern that extended into the dermis with internal pseudolumina that contained detached tumour cells. Histo-chemically, tumour cells were mucin-negative. Immuno-histochemistry revealed intra-cytoplasmic reactivity for cytokeratin MNF116 and cytokeratin 10 with strong staining intensity for Glut1 located on the cell membrane, however, cells were negative for cytokeratin 7, 8 and 20, Vimentin and vWF, suggesting they originated from stratified epithelia and not from ductal or glandular epithelia as well as differentiating from sarcomas like angiosarcoma. Immuno-staining results further verified that the tumour was a proliferative lesion of the squamous cell type but was an uncommon entity that may have differentiated from ordinary squamous cell carcinoma as reported in the veterinary literature.     

Plasmacytoid urothelial carcinoma of the urinary bladder: A case report and immunohistochemical study

We report a rare case of plasmacytoid urothelial carcinoma (PUC) of the urinary bladder. A 50-year-old man complained of pollakiuria and urinary incontinence. MRI detected a bladder tumor invading the rectum and bilateral hydroureteronephrosis. Radical cystectomy with partial resection of the rectum was performed, and ileus due to peritoneal dissemination occurred 2 years after surgery. He died of the disease 42 months after the initial presentation. Histologically, urothelial carcinoma in situ with a focal invasive urothelial carcinoma (IUC) component and widely spread PUC was observed. There was no lymph node metastasis. PUC cells had eccentrically placed nuclei and eosinophilic cytoplasm resembling plasmacytoma cells, and proliferated with a single-cell infiltrative pattern to the outside of the bladder. IUC cells with intracytoplasmic lumina were focally intermingled with PUC cells. Immunohistochemically, PUC cells were positive for cytokeratin 7, epithelial membrane antigen, and CA19-9, but negative for cytokeratin 20, E-cadherin, p63, and lymphoid markers. The Ki-67 labeling index of PUC cells was 9.3%. IUC containing intracytoplasmic lumina showed intermediate features of conventional IUC and PUC morphologically and immunohistochemically. PUC is a distinct entity of bladder cancer with a high propensity for invasion and poor prognosis.     

Glycogen-rich clear cell carcinoma arising from minor salivary glands of the uvula. A case report

Glycogen-rich clear cell carcinoma arising from minor salivary glands of the uvula in a 35-year-old woman is reported. This tumor was composed of nests and cords of clear cells containing cytoplasmic glycogen but no mucin. The epithelial nature of this lesion was obvious because of positive immunoreactivity for cytokeratin and epithelial membrane antigen, and the presence of immature lumina and intercellular spaces lined by many microvilli, associated with desmosomal junctions and basal lamina, as revealed by ultrastructural study. However, no myoepithelial cells could be detected. From these findings, it may be concluded that this tumor corresponds to glycogen-rich clear cell carcinoma (a variant of clear cell tumor), revealing glandular differentiation.     

Histopathological and immunohistochemical findings in a case of glycogen-rich clear cell carcinoma of the breast

Glycogen-rich clear cell carcinoma (GRCC) of the breast is a rare variant of primary breast carcinoma that was first described by Hull et al. in 1981, and is characterized by carcinoma cells containing an optically clear cytoplasm and intracytoplasmic glycogen. The present case involved a 33-year-old female. She had noticed a lump in the inner quadrant of the left breast. The tumor obtained by enucleation biopsy had an irregular shape. The tumor cells exhibited sharply defined borders, polygonal contours, a clear or finely granular cytoplasm, and moderate nuclear atypia. The tumor cells showed a positive reaction with periodic acid Schiff, eliminated by diastase digestion. The tumor was diagnosed as GRCC. There was no nodal metastasis. Immunohistochemically, the tumor cells were positive for cytokeratin, epithelial membrane antigen, HER2, and p53, but negative for estrogen receptor (ER) and progesterone receptor (PR). Although the biological behavior of GRCC is difficult to predict in view of the very limited number of case reports, the prognosis of GRCC may be associated with not only histopathological subtype but also other clinicopathological factors, such as size, status of invasion, status of nodal metastasis, nuclear grade, ER, PR, HER-2, p53 and so on. To clarify the pathogenesis of mammary GRCC, the systematic study of additional well-documented cases with long-term follow up will be necessary.     

Pure acinic cell carcinoma of the breast in an 80-year-old Japanese woman

Acinic cell carcinoma of the breast is an uncommon neoplasm. Since the first case of this rare variant of breast carcinoma was reported in 1996, only 10 cases have been reported in the English-language literature. Reported herein is the first case of primary acinic cell carcinoma of the breast in a Japanese woman. To the naked eye, the tumor appeared well circumscribed and the cut surface was grayish-pink and hemorrhaging. Microscopically, the tumor was predominantly made up of a monotonous proliferation of cells with a finely granular cytoplasm, resembling acinic cells of the parotid gland. Some neoplastic cells had a clear cytoplasm. In spite of extensive sampling, no common histological patterns of breast carcinoma such as in situ and invasive ductal carcinoma were recognized in the present case, indicating that the present case was pure acinic cell carcinoma. In addition, the immunohistochemical profile of this tumor was identical to that of the acinic cell carcinoma of the salivary gland: estrogen receptor, progesterone receptor, HER2 and cytokeratin (CK)20 were negative and amylase and CK7 were positive. The patient has been well for 22 months since the wide local excision of the tumor and no signs of salivary neoplasm are evident to date.     

GLYCOGEN-RICH CLEAR CELL CARCINOMA ARISING FROM MINOR SALIVARY GLANDS OF THE UVULA. A Case Report

Glycogen-rich clear cell carcinoma arising from minor salivary glands of the uvula in a 35-year-old woman is reported. This tumor was composed of nests and cords of clear cells containing cytoplasmic glycogen but no mucin. The epithelial nature of this lesion was obvious because of positive immunore-activity for cytokeratin and epithelial membrane antigen, and the presence of immature lumina and intercellular spaces lined by many microvilli, associated with desmosomal junctions and basal lamina, as revealed by ultrastructural study. However, no myoepithelial cells could be detected. From these findings, it may be concluded that this tumor corresponds to glycogen-rich clear cell carcinoma (a variant of clear cell tumor), revealing glandular differentiation. ACTA PATHOL JPN 38: 1227∼1234, 1988.     

Ductal Cell Carcinoma of the Kidney with Extensive Signet Ring Cell Mucosecreting Areas: A Case Report with Immunohistochemical Analysis

We present the case of a 45-year-old patient with a renal ductal cell carcinoma arising in the Bellini ducts that was composed of histologically well-differentiated tubulopapillary and cystic areas with desmoplastic stroma, extensive mucosecreting areas, and regions depicting a transition between these two constituents. The mucosecreting component was mostly formed by signet ring tumor cells containing cytoplasmic Alcian blue-PAS-stainable mucins. The tubulopapillary and cystic areas of the tumor showed the immunohistochemical staining for low and high molecular weight cytokeratin, EMA, vimentin and Ulex europaeus, characteristic of ductal cell carcinoma. The mucosecreting cells also presented intense positive staining for cytokeratin and vimentin, and this is quite similar to observations reported in some forms of gastrointestinal cancer with rhabdoid features that are indicative of poor prognosis. Our findings suggest that mucosecreting areas with signet ring cells represent an extreme metaplastic change that can seldom occur in certain forms of renal tumors.     

Clear cell carcinoma of the breast with immunohistochemical evidence of divergent differentiation

Primary clear cell carcinoma of the breast is a rare tumor. The clear cell morphology of the neoplastic population in these tumors has been ascribed to the presence of intracellular lipid, mucin or glycogen, or to myoepithelial, apocrine, or neuroendocrine differentiation. However, a clear cell neoplasm exhibiting evidence of a range of differentiation has not been previously reported. We describe a case of a glycogen-rich primary clear cell breast carcinoma occurring in a 59-year-old woman that showed positivity for apocrine and neuroendocrine markers, as well as possible myoepithelial differentiation. The tumor was a 4-cm mass composed predominantly of periodic acid-Schiff-positive clear cells arranged in a solid, infiltrative pattern. Immunohistochemical staining of the tumor cells was variably positive for cytokeratin, progesterone receptors, gross cystic disease fluid protein-15, neuron specific enolase, chromogranin, and S-100 protein and negative for estrogen receptors, smooth muscle actin, CD31, and CD34. The patient refused any form of further investigation or treatment, but shows no evidence of recurrence or metastatic disease after 18 months of follow-up.     

Immunohistochemical distinction of human carcinomas by cytokeratin typing with monoclonal antibodies.

Carcinomas of different origin have been tested in immunofluorescence microscopy with the monoclonal murine antibodies CK1-CK4, which recognize a single cytokeratin polypeptide (human cytokeratin No. 18) present in simple but not in stratified squamous epithelia, and with the monoclonal antibody KG8.13 and guinea pig kerA antibodies, both of which recognize a variety of cytokeratins common to almost all epithelial cell types. Tumors derived from simple epithelia, including adenocarcinomas and some other tumors such as ductal breast carcinomas, were strongly stained by all three antibodies. So was a transitional carcinoma of the bladder. In contrast, basal cell epithelioma, cloacogenic carcinoma, and squamous cell carcinoma of skin, tongue, and esophagus appeared negative with CK1-CK4 but positive with the other two antibodies. Other squamous cell carcinomas derived from epiglottis and cervix uteri showed a mixture of positive and negative cells when tested with CK1-CK4, although all tumor cells were positive when tested with KG8.13 and with kerA. Thus, use of an appropriate collection of cytokeratin antibodies with different specificities not only allows tumors of epithelial origin to be distinguished from other tumor types but, in addition, allows a further subdivision of carcinomas in relation to their histologic origin.