Comparison of Immunohistochemical Expression of Cytokeratin 19, c-KIT, BerEP4, GATA3, and NUTM1 Between Porocarcinoma and Squamous Cell Carcinoma

Abstract

Distinguishing porocarcinoma from squamous cell carcinoma (SCC) is clinically significant; however, differential diagnosis can often be challenging. This study sought to confirm the diagnostic utility of cytokeratin 19, c-KIT, BerEP4, GATA3, and NUTM1 immunohistochemistry in distinguishing porocarcinoma from SCC. Immunohistochemical analysis of cytokeratin 19, c-KIT, BerEP4, GATA3, and NUTM1 in 14 porocarcinomas and 22 SCCs was performed; the extents and intensities of expression of these markers were recorded. The statistical associations of the immunoexpression between porocarcinoma and SCC were analyzed using the Pearson x 2 test. Cytokeratin 19 was positive in 13 (92.9%) of 14 porocarcinomas, and for all the positive cases, staining was strong and evident in .20% of the tumor cells. By contrast, 9 (40.9%) of 22 SCCs expressed cytokeratin 19 (P = 0.0018), of which 6 showed extremely focal (#10% of the tumor cells) expression. Of the 14 porocarcinomas, 11 (78.6%) cases showed c-KIT positivity, whereas only 3 of 22 SCCs (13.6%) expressed c-KIT focally (P = 0.0001). In addition, BerEP4 immunostaining differed between porocarcinomas and SCCs (57.1% vs. 9.1%, respectively; P = 0.0017). However, no significant difference between the groups was reported in terms of GATA3 expression (57.1% vs. 72.7%, respectively; P = 0.3336). NUTM1 was expressed in 4/14 (28.6%) porocarcinomas but not in the SCCs. Immunohistochemistry for cytokeratin 19, c-KIT, and BerEP4 could be helpful in distinguishing porocarcinomas from SCCs. In addition, NUTM1 immunoexpression is highly specific, although not sensitive, to porocarcinomas. GATA3 immunohistochemistry has no meaningful implications in the differential diagnosis of porocarcinoma and SCC.

Diagnosis and Management of Porocarcinoma

“…The Goto group found all of the PC tumors to be positive for CD117, while only six of the SCC cases (19%) were positive for CD117, suggesting that CD117 could be a useful marker for differentiating PC from cutaneous SCC. Immunohistochemical staining for cytokeratin 19, c-KIT, and BerEP4 is also useful when differentiating PC from SCC [ 47 ]. Goto et al revealed that cytokeratin 19 was expressed in 13 of 14 PC cases (92.9%) but was positive in only 9 of 22 SCC cases (40.9%).…”

Seborrheic Keratosis With Malignant Transformation (Invasive or Noninvasive Squamous Cell Carcinoma Arising in Seborrheic Keratosis): A Clinicopathologic and Immunohistochemical Study of 11 Cases

“…Similarly, squamous cell carcinoma arising in seborrheic keratosis is often composed of basaloid tumor cells that are similar to poroid tumor cells of porocarcinoma. Porocarcinoma frequently expresses BerEP4, c-kit, CK19, NUT, and YAP1 but not GATA3, 50,51 whereas carcinomas arising in seborrheic keratosis frequently express GATA3 but not BerEP4, c-kit, CK19, NUT, and YAP1. Thus, it is easy to distinguish carcinoma arising in seborrheic keratosis from porocarcinoma using immunohistochemistry for the abovementioned markers.…”

KITLG Copy Number Germline Variations in Schnauzer Breeds and Their Relevance in Digital Squamous Cell Carcinoma in Black Giant Schnauzers

“…There is just one case report of a dog with an oral collision tumour of SCC and malignant melanoma that examined the expression of the KIT receptor in the neoplastic cells—but only melanocytic cells were positive [ 40 ]. In human dermal SCC, only 3 of 22 neoplasms showed expression of the KIT receptor [ 41 ]. Unfortunately, several cases of dSCC in the present study were not diagnosed in our laboratory, and samples were not available for further analyses, but prospective case collections should focus on this to achieve a better understanding of the pathogenetic correlations.…”