Assessment of Immunohistochemical Expression of Vitamin D Receptor in Surgically Excised Cutaneous Melanoma from Egyptian Patients

Abstract

Abstract Background: Vitamin D, acting via the vitamin D receptor (VDR), has antitumor effects through inhibition of proliferation and angiogenesis. Some previous studies showed an inverse correlation between VDR expression and the progression of cutaneous melanoma, whereas other studies did not confirm this correlation, suggesting a probable ethnic/geographic effect. We aimed to evaluate the expression pattern of VDR in cases of cutaneous melanoma in a Middle Eastern country, Egypt. Materials and Methods: A total of 42 paraffin blocks and slides from 42 patients were retrieved from the pathology archives of our institution and immunohistochemically stained against VDR. The density and pattern of VDR immunostaining in positively stained cases were analyzed and compared with various demographic, clinical, and histological parameters of Egyptian patients who underwent surgical excision for cutaneous melanoma between 2017 and 2022. Results: A total of 37 cases (88.1%) expressed VDR, showing no significant correlation with the tumor site, size, metastasis, or invasion. In contrast, a statistically significant difference was observed between nuclear and cytoplasmic VDR expression. Nuclear expression was associated with unfavorable tumor characteristics, including increased Breslow thickness, Clark level, and vascular invasion. Conclusion: VDR expression can serve as a prognostic marker in the histopathological evaluation of cutaneous melanoma; the utility of nuclear versus cytoplasmic VDR expression should be further investigated in future research incorporating genetic analysis. Our findings, in contrast to several previous studies but in agreement with a few, suggest an association between nuclear staining and tumor progression.