Stromal SPARC Expression Patterns and Diagnostic Potential in Mucocutaneous Squamous Cell Carcinoma
- *Corresponding Author:
- Kristen M Paral
Department of Pathology
University of Chicago
Maryland Ave, Chicago
IL 60637, USA
E-mail: [email protected]
Received date: April 20, 2016; Accepted date: May 19, 2016; Published date: May 23, 2016
Citation: Paral KM, Cipriani NA (2016) Stromal SPARC Expression Patterns and Diagnostic Potential in Mucocutaneous Squamous Cell Carcinoma. J Clin Exp Pathol 6:274. doi: 10.4172/2161-0681.1000274
Copyright: © 2016 Paral KM, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Background: SPARC (secreted protein acidic and rich in cysteine) is a key player in the stromal remodeling associated with invasive carcinomas, and its detection by immunohistochemistry may prove diagnostically useful in detecting invasion. The present study explores stromal SPARC expression patterns in invasive mucocutaneous squamous cell carcinoma (SCC). The patterns are then compared to those of SMA, a relatively well-studied but imperfect marker of cancer-associated stroma.
Methods: Nineteen cases of infiltrating keratinizing SCCs from skin and mucous membranes were assessed semi-quantitatively for immunoreactivity with anti-SMA or anti-SPARC antibodies in tumor-free and tumor-associated stroma.
Results: All cases of invasive SCCs (n=19) demonstrated stromal expression of both SMA and SPARC. However, SPARC showed more diffuse reactivity than SMA, with SPARC demonstrating a mean percentage reactivity range of 50-75%, versus 25-50% for SMA. In tumor-free stroma, SMA was negative in all cases, whereas SPARC was positive in up to 5% of dendritic stromal cells in more than half of the cases.
Conclusions: Stromal SPARC overexpression is a consistent finding in invasive SCC, and SPARC is more sensitive but less specific for cancer-associated stroma than SMA. While H&E examination remains the gold standard for determining whether invasion is present, stromal SPARC expression patterns may serve as an adjunct to the histopathologic impression.