Sarcomatoid carcinoma

Focal/Patchy Positive Carcinomas Sarcomatoid carcinomas... 

Common in renal, endometrial, ovarian serous, salivary gland, follicular thyroid, and sarcomatoid (spindle cell) carcinomas, "basal-like" breast carcinomas, as well as in the epithelial and stromal components of malignant mixed mullerian tumors... 

FIGURE 8.9 This sarcomatoid carcinoma of lung (A) richly coexpresses CAMS.2 (B) and vimentin (C) Most carcinomas of this type in lung and upper aerodigestive tract are sarcomatoid squamous cell carcinomas. 

Thompson LD, Wieneke JA, Miettinen M, et al. Spindle cell (sarcomatoid) carcinomas of the larynx a clinicopathologic study of 187 cases. Am J Surg Pathol. 2002 26(2) 153-170. 

Comparatively few examples of sarcomatoid thymic carcinoma (STC) have been reported. 499-201 Microscopically, this lesion is characterized by fascicles of fusiform and pleomorphic tumor cells, with little internal organization. Some cases, however, contain limited foci in which cohesive epithelioid cell nests are admixed with... 

I immunolabeling for keratin (K) (A) in primary sarcomatoid carcinoma of the thymus (B). 

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. 

FIGURE 12.10 This region of sarcomatoid carcinoma shows im-munostaining of the spindle cells for low molecular weight keratin. X400. 

Lucas and colleagues immunostained 20 mesotheliomas with sarcomatoid components (10 biphasic and 10 sarcomatoid) for pan cytokeratin, CK5/6, cal-retinin, WTl, thrombomodulin, and smooth muscle actin. They compared the immunophenotypic profile of these tumors with 24 high-grade sarcomas, 10 pulmonary sarcomatoid carcinomas, and 16 epithelioid mesotheliomas. The 10 pulmonary sarcomatoid carcinomas were also immunostained for TTF-1. Their results are shown in Table 12.24. They concluded that 1) there was a decrease in epithelial and mesothelial epitopes in sarcomatoid mesothelioma 2) there was a wide immunophenotypic overlap among sarcomatoid... 

We have not found the expression of broad-spectrum keratin (AE1/AE3 keratin) in sarcomas or the degree of calretinin expression in sarcomatoid mesotheliomas, sarcomas, or sarcomatoid carcinomas noted by Lucas and coworkers.In our experience, broad-spectrum keratin is rarely found (<1% of cases) in sarcomas. Calretinin expression is found in a maximum of 20% of sarcomatoid mesotheliomas and is not seen in sarcomas or sarcomatoid carcinomas. Others have found similar immunoreactions (see the paragraphs that follow). 

Pleomorphic mesotheliomas exist and are composed of pleomorphic epithelioid and sarcomatoid cells. Occasional multinucleated macrophage giant cells are associated with the tumor cells. Pleomorphic mesotheliomas need to be differentiated from pleomorphic carcinomas of the lung. In most instances, pleomorphic mesotheliomas express pan cytokeratin and vimentin. 

Sarcomatoid renal cell carcinomas can metastasize to the pleura in a macroscopic distribution identical to mesothelioma and very closely simulate a sarcomatoid mesothelioma.This tumor is considered as a pseu-domesotheliomatous carcinoma but not a primary pulmonary pseudomesotheliomatous carcinoma. The immunostaining pattern of such neoplasms can be identical to a sarcomatoid mesothelioma. The situation can be further complicated because sarcomatoid mesotheliomas can metastasize to the kidney. If an individual is known to have a sarcomatoid renal cell carcinoma and has a spindle cell neoplasm of the pleura, one must consider... 

Humphrey PA, Scrogjs MW, Roggli VL, et al. Pulmonary carcinomas with a sarcomatoid element An immunohistochemical and ultrastructural analysis. Hum Pathol. 1988 19 155-165. 

Nappi O, Glasner SD, Swanson PE, et al. Biphasic and mono-phasic sarcomatoid carcinomas of the lung A re-appraisal of carcinosarcomas and spindle cell carcinomas. Am J Clin Pathol. 1994 102 331-340. 

Sarcomatoid carcinomas may sometimes express keratin focally, and the best approach to their recognition is to employ a broadly reactive mixture of monoclonal antikeratins as a screening reagent. Keratin 5/6 could be included as a specific target therein because it is squa-mous-cell selective. 

FIGURE 13.1 Sarcomatoid (spindle-cell) squamous cell carcinoma of the skin (A), demonstrating diffuse reactivity for vimentin (B) and keratin (C). 

Hall JM, Saenger JS, Fadare O. Diagnostic utility of p63 and CDIO in distinguishing cutaneous spindle cell/sarcomatoid squamous cell carcinoma and atypical fibroxanthoma. Int J Clin Exp Pathol. 2008 1 524-530. 

Vimentin R Positive in spindle cell (sarcomatoid) carcinomas 152, 154, 303... 

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. 

Rosty D, Prevot S, Tiret E. Adenocarcinosarcoma in Barrett s esophagus Report of a case. Int J Surg Pathol. 1996 4 43. lezzoni JC, Mills SE. Sarcomatoid carcinomas (carcinosarcomas) of the gastrointestinal tract a review. Semin Diagn Pathol. 1993 10 176-187. 

Nakayama Y, Murayama H, Iwasaki H, et al. Gastric carcinosarcoma (sarcomatoid carcinoma) with rhabdomyoblastic and osteoblastic differentiation. Pathol Int. 1997 47 557-563. 

In some DAs the hallmarks of ductal differentiation may be lacking. Such cases are classified as undifferentiated carcinoma.In some, epithelial-to-mesenchymal transition can be so complete that the tumor may resemble sarcomas (i.e., sarcomatoid carcinoma)and only after adjunct studies such as immunohistochemistry can the ductal nature of the tumor be elucidated. ... 

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