The prevalence and prognostic value of CD168 in early-stage oral squamous cell carcinoma

CD168 has been established as a negative prognostic marker in various tumor entities leading to a poor prognosis. Regarding OSCC, there is a lack of comprehensive studies that examine the correlation between CD168 expression and clinical outcome, hindering the implementation of this prognostic factor into clinical practice.

This retrospective analysis included all patients with primary pT1 and pT2 pN0 OSCC who received surgical therapy without the need for adjuvant therapy (pN0, M0, R0) over a seven-year long period. Immunohistochemical staining for CD168 and Mib/Ki67 was evaluated using tissue microarrays of primary tumors and correlated with clinical outcome. A cut-off value for CD168 expression of ≥10 % was considered as positive.

A total of 139 patients (male: 91 (65.5 %), female: 48 (34.5 %)) with a mean age of 61.2 years were included (mean follow-up: 62.6 months). CD168 expression was evident in 35 (25.2 %) tumors leading to higher levels of Mib/Ki67 positivity (p < 0.001). Tumor biopsies of stage T2 OSCC stained positive for CD168 more frequently when compared to T1 tumors (p = 0.002). Tumors with CD168 expression ≥ 10 % had a significantly lower OS (p < 0.001) and RFS (p = 0.011) compared to patients with lower expression. Multivariate Cox regression identified CD168 status as a risk factor for OS (HR 2.10, CI: 1.06-4.14; p = 0.033).

Our results demonstrate a significant proportion of CD168-positive tumors in OSCC and suggest an impact on prognosis, particularly with regard to OS.