Invasive squamous cell carcinoma: comparison of differentiation grade and tumour depth by anatomical site in 1666 tumours

Abstract

SummaryBackground. Invasive squamous cell carcinomas (SCCs) presents with different grades of differentiation and depths of invasion. Aim. To compare the grade of differentiation, tumour diameter and tumour depth by anatomical site in invasive SCC. Methods. Retrospective clinical and histopathological data on consecutive cases of SCC came from a clinic in Sydney, Australia were assessed. A multinomial logistic regression model was applied to compare grades of differentiation by age, sex, anatomical sites, and histological tumour maximum diameter and depth. Results. In total, 1666 SCCs were identified, including 82.1% (n = 1367) welldifferentiated, 13.3% (n = 222), moderately differentiated and 4.6% (n = 77) poorly differentiated SCCs. Patients with poorly differentiated tumours were more likely to be older and male (both P < 0.001). The most common site for poor differentiation was the scalp in men (n = 12; 15.6%) and the cheek or chin in women (n = 7; 9.1%). In the multivariate model, compared with well-differentiated SCC, older age was significantly associated with poorly and moderately differentiated SCC (P < 0.01 and P = 0.02, respectively). Larger tumour diameters were related to poor differentiation (P = 0.03). Ear, forehead and chest sites had increased tumour depth and poor differentiation.Conclusions. This study found increased rates of poorly differentiated SCC on the forehead and cheek for both sexes, while men displayed increased rates of poorly differentiated SCC on the bald scalp and the ears. Tumour diameter and depth increased as tumours varied from well-differentiated to moderately differentiated and from moderately differentiated to poorly differentiated. An increase in depth and increased prevalence of poorly differentiated tumours were found on the ears for men and on various facial sites for both sexes.

Early Squamous Cell Carcinoma With Perineural Invasion: A Prospective Study Examining Anatomic Site, Tumor Surface Diameter, Invasion Depth, and Grade of Differentiation in 1,772 Consecutive Cases

“…Tumor invasion depths progressively increased in the shift to poor differentiation, consistent with previous studies [15].…”

“…Combining epithelial membrane antigen with cytokeratin MNF116 has been stated to facilitate diagnosing PNI when both of these immunohistochemical stains are positive [15].…”

Poorly differentiated cutaneous squamous cell carcinomas have high incomplete excision rates with UK minimum recommended pre-determined surgical margins

“…Our study population had a high proportion of high-risk features compared to comparable literature. For example, 62.8% of our patients had moderately or poorly differentiated lesions (compared with other series showing 17.9-33.8% 13,14 ). There was also a higher population of tumours ≥20 mm at 30.4% (compared with 13.1-20.6% 9,14 ) and Perineural invasion at 5.7% (compared with 4.1-6.4% 9 , 14-16 ) ( Table 3 ).…”

Consistent downregulation of the cleft lip/palate-associated genes IRF6 and GRHL3 in carcinomas

“…It is established that the differentiation grade in SCC’s is an important (inversely proportional) indicator of tumor size, depth and aggressiveness ( 53 ). As IRF6 is regulating the proliferation-differentiation balance of epithelial cells, it is not unexpected to see an inverse correlation of IRF6 levels with the differentiation grade of cutaneous SCCs ( 45 , 54 ).…”