Spindle-cell differentiation

SPINDEE CEEE DIFFERENTIATION (SARCOMATOID CARCINOMA) Similar to the colon and esophagus, spindle cell differentiation has been described in gastric carcinomas. These neoplasms usually stain with vimentin and EMA and variably with cytokeratin.1 4154 gg Esophagus earlier for additional discussion. 

UNDIFFERENTIATED NEOPLASMS AND CARCINOMAS WITH RHABDOID DIFFERENTIATION These neoplasms are immunohisto-chemically similar to poorly differentiated carcinomas with spindle cell differentiation.The two most common gastrointestinal locations for rhabdoid carcinomas are the colon and stomach.This variant most... 

The BCL-2 (B-cell lymphoma-2) proteins are anti-apoptotic polypeptides that are differentially expressed in some soft tissue lesions. Those that commonly label immunohistologically include solitary fibrous tumor, spindle-cell lipoma, Kaposi s sarcoma, and monophasic... 

Leiomyosarcomas are most commonly found in the retroperitoneum in adults. They uncommonly occur in the deep soft tissues of the extremities but may be seen in more superficial sites, particularly in the dermis and subcutis. The differential diagnosis of LMS traditionally includes other sarcomas composed of intersecting spindle-cell fascicles, including fibrosarcoma, MPNST, synovial sarcoma, and spindle cell rhabdomyosarcoma. Additional conditions such as IMT (inflammatory pseudotumor), neurofibroma, and hemangiopericytoma (see Fig. 4.5) are also considerations. 

Malignant peripheral nerve sheath tumor (MPNST) may likewise assume a pleomorphic appearance. In most instances, that tumor variant shows patterns of reactivity for S-100 protein, CD56, CD57, and collagen type IV that are superimposable with those of better differentiated (spindle cell) MPNSTs." In the absence of focal S-100 protein expression and foci with conventional appearances, it is very difficult (if not impossible) to render this diagnosis with certainty. Unlike spindle cell variants of MPNST, pleomorphic subtypes have not been shown to be desmin-reactive. 

Carlson JW, Fletcher CDM. Immunohistochemistry for beta-catenin in the differential diagnosis of spindle-cell lesions Analysis of a series and review of the literatrrre. Histopathology. 2007 51 509-514. 

Encoded by the MUCI gene on chromosome I and a derivative human antigen, EMA is a transmembrane glycoprotein of the breast mucin complex, and its expression is increased in carcinomas.Unlike normal breast, in which EMA is present on the apical cell membrane, neoplasms demonstrate EMA on the entire circumference of the cell membrane. Increased amounts of the large glycoprotein interfere with cell-to-cell and cell-to-matrix adhesion in neoplastic cells. The utility of EMA antibody is in the detection of epithelial differentiation, as a supplement to the cytokera-tins. Spindle cell, small cell, and large cell neoplasms may on rare occasion be stained with EMA but may be only focally positive for cytokeratins. 437... 

The diagnosis of spindle cell carcinoma (SPCC) requires the identification of a component of squamous neoplasia or epithelial differentiation of the spindle cells. 

Myoepitheliomas should be distinguished from pleomorphic adenomas and other salivary gland neoplasms. But the differential diagnosis may also include non-salivary gland lesions, depending on the predominant cell type in the myoepithelioma. For example, spindle cell myoepitheliomas should be differentiated from leiomyomas, schwannomas, and other spindle cell lesions. 

Ordonez and coworkers,5 of 32 (15.6%) cases of anaplastic carcinoma exhibited TGB immunoreactivity in a small number of cells using both monoclonal antibodies and polyclonal antisera. In this series, positivity was present in 3 of 8 giant cell, 1 of 4 spindle cell, and none of 6 squamoid or 13 mixed variants. Examination of serial sections in these cases failed to reveal evidence of entrapped normal follicular cells or foci of differentiated thyroid carcinoma. Other authors, however, have failed to demonstrate any TGB immunoreactivity in anaplastic carcinomas except in foci of residual differentiated tumor. 

Most studies report TTF-1 positivity in more than 90% of pulmonary small cell NE carcinomas. In the study of Oliveira and colleagues, " TTE-1 was present in 19 of 20 (95%) well-differentiated pulmonary NE tumors (including typical and atypical carcinoids) and in 8 of 10 (80%) metastases of these tumors. On the other hand, Du and colleagues reported TTE-1 positivity in 28%, 29%, and 37% of typical carcinoids, atypical carcinoids, and large cell NE carcinomas, respectively. Interestingly, TTE-1 positivity was more commonly present in peripheral carcinoids of spindle cell type than... 

Immunoreactants Used in the Differential Diagnosis of Spindle Cell Indeterminate and Undifferentiated Neoplasms of the Mediastinum... 

FIGURE 11.32 Markers of interest in the differential diagnosis of malignant epithelial spindle cell tumors of the mediastinum. 

Sarcomatoid carcinoma, also referred to as carcinosarcoma, spindle cell carcinoma, blastoma, and teratocarci-noma, are neoplasms of epithelial derivation that show variable differentiation. Sarcomatoid carcinoma has been reviewed conceptually by Wick and Swanson. Several studies have evaluated sarcomatoid carcinoma by immunohistochemistry using keratin antibodies and/ or electron microscopy. These studies concluded that the spindle cell component of the neoplasm was of epithelial derivation. In most instances, the spindle cells coexpress keratin and vimentin (Figs. 12.10 and 12.11) or occasionally keratin and other intermediate filaments such as desmin or actin. 

Pleomorphic carcinoma, as defined by Fishback and associates,is a neoplasm that occurs predominantly in older patients and is composed predominantly of spindle cells and large pleomorphic giant cells. In 78 cases, the authors found foci of squamous differentiation in 8% of cases, large cell undifferentiated carcinoma in 25% of cases, and adenocarcinoma in 45% of cases. The remaining 22% of the neoplasms were composed of neoplastic... 

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