Sarcomatoid (Spindle Cell) Carcinoma of the Head and Neck Mucosal Region: A Clinicopathologic Review of 103 Cases from a Tertiary Referral Cancer Centre

Abstract

Sarcomatoid carcinomas are biphasic tumors proven to be monoclonal dedifferentiated forms of conventional squamous carcinomas. This study evaluates their clinicopathologic characteristics in head and neck mucosal sites and the problems in distinguishing them from other spindle cell tumors. A total of 103 cases with a confirmed diagnosis of sarcomatoid carcinoma accessioned in the pathology department of a tertiary referral cancer centre over a period of 7 years (2004)(2005)(2006)(2007)(2008)(2009)(2010) were studied. An algorithm used for their diagnosis is presented. Ages of the patients were 22-90 years (median 53 years), and male:female ratio was 3.7:1. Site distribution was oral cavity (n = 65, 63.1%), larynx (18, 17.5%), oropharynx/hypopharynx (12, 10.7%), maxilla (6, 5.8%) and metastatic nodes (2, 1.9%). A large number of patients (95%) presented with a mass lesion of less than 1 year duration. Histopathologically, epithelial differentiation was evident on morphology in 48 (46.6%) cases, only on IHC in 34 (33%) cases, and in 21 (20.4%) no epithelial differentiation was seen. Typically, tumors were polypoidal (92, 89.3%) and ulcerated (95, 92.2%) with cells arranged predominantly in fascicles (59, 57.3%) or storiform pattern (17, 16.5%) amidst collagenous (50, 48.5%) or myxoid matrix (35, 34%). Anaplasia (2?/3?) and mitosis[10 per 10 HPF were noted in 96 (93.2%) cases. IHC was done in 82 cases; 55 (66.7%) showed positivity for epithelial markers with aberrant expression of mesenchymal markers in 43 (41.7%). Diagnosis of sarcomatoid squamous carcinoma is challenging because of overlapping histopathological features with other spindle cell tumors. Understanding their clinicopathologic characteristics facilitates their diagnosis and appropriate clinical management.

Pseudomyogenic Hemangioendothelioma: A Vascular Tumor Previously Undescribed in the Oral Cavity

“…Nuclear reactivity to INI 1 is the key immunohistochemical event in the PMH that allows it to be differentiated from the INI 1 negative epithelioid sarcoma and therefore the INI 1 reactivity of the PMH should be viewed only in this context. Sarcomatoid (spindle cell) carcinoma of the oral cavity is a diagnostically challenging tumor and may show no epithelial differentiation at either the histopathological or immunohistochemical level [8]. Those that show epithelial differentiation at the immunohistochemical level, express cytokeratins including AE1/AE3.…”

“…Also, sarcomatoid carcinomas always show anaplastic features. Frank areas of epithelial differentiation and dysplasia of the surface epithelium may also be seen in many cases [8].…”

A Review of Primary Osteosarcoma of the Larynx and Case Report

“…While it is known that epithelial differentiation may be difficult to demonstrate in sarcomatoid carcinoma, the complete lack of any evidence of epithelial differentiation in this case favours the likelihood of a primary sarcoma despite the fact that derivation from a preceding carcinosarcoma cannot be excluded with certainty [30,31]. Despite careful attention to the mentioned challenges that may prevent detection of preceding carcinosarcoma or epithelial differentiation, the complete lack of such evidence in the current tumour supports the diagnosis of primary osteosarcoma of the larynx.…”

“…The presence of extensive ulceration may furthermore prevent the histological detection of dysplasia or squamous cell carcinoma in situ in the overlying epithelium. Sampling errors and technical factors may also confound the pathologist's ability to detect epithelial differentiation [30,31].…”

“…The presence of malignant osteoid production and careful exclusion of epithelial differentiation distinguishes primary osteosarcoma from carcinosarcoma/sarcomatoid carcinoma, some of which are well known to contain osteoid [8,[27][28][29][30][31][32][33]. Thompson et al [30] and Viswanathan et al [31] described the largest series of laryngeal spindle cell (sarcomatoid) carcinoma, of 187 and 103 cases respectively.…”