Original article / research
Differentiating Psoriasis from Psoriasiform Dermatitis using Proliferation Markers Ki-67 and Cyclin D1: A Cross-sectional Study
EC11-EC15
Correspondence
Dr. Anand Kumar Verma,
Professor, Department of Pathology, ESI-Post Graduate Institute of Medical Sciences and Research (ESI-PGIMSR), Basaidarapur, New Delhi-110015, India.
E-mail: anandverma1961@gmail.com
Introduction: Psoriasis shares several clinical and histopathological features with other psoriasiform dermatoses. Differentiating it from other psoriasiform dermatitis is a diagnostic challenge which holds therapeutic as well as prognostic significance.
Aim: To compare the immunohistochemical expression of proliferative markers Ki-67 and Cyclin D1 in psoriasis and other psoriasiform dermatitis and to determine if these markers can help differentiate them.
Material and Methods: A cross-sectional study was conducted at the Department of Pathology, ESI-Post Graduate Institute of Medical Sciences and Research (ESI-PGIMSR), a tertiary care hospital in Basaidarapur, New Delhi, India, from April 2023 to August 2024, where 27 biopsies each of psoriasis and psoriasiform dermatitis were included. Immunohistochemistry (IHC) was performed using Ki-67 and Cyclin D1 antibodies, and their expression was evaluated. Three parameters—total epidermal cell count, suprabasal epidermal cell count, and the suprabasal-to-total epidermal cell count ratio—were compared between the two groups. Receiver Operating Characteristic (ROC) curve analysis was used to determine optimal cut-off values for these parameters. An Independent t-test was used to analyse the results using the Statistical Package for Social Sciences (SPSS) version 20.0.
Results: The total epidermal cell count was significantly higher in psoriasis than in psoriasiform dermatitis for both markers. For Ki-67, the mean count was 386 vs 356 cells/mm2 (p<0.001), while for Cyclin D1 it was 360 vs 329 cells/mm2(p<0.001). Similarly, the suprabasal epidermal cell count was also higher in psoriasis for both Ki-67 (343 vs 298 cells/mm2; p<0.001) and Cyclin D1 (333 vs 305 cells/mm2 - p=0.036). The suprabasal-to-total epidermal cell count ratio was significantly higher in psoriasis, with values of 89% vs 84% for Ki-67 (p=0.001). ROC curve analysis yielded cut-off values of 370 and 318 cells/mm2 for the total and suprabasal Ki-67 counts, respectively and 396 and 325 cells/mm2 for the total and suprabasal Cyclin D1 counts, respectively.
Conclusion: Ki-67 and Cyclin D1 exhibit significantly different immunohistochemical expression patterns in psoriasis and psoriasiform dermatitis. Quantitative assessment of these markers, along with objective cut-off values, may serve as an objective adjunctive diagnostic tool. IHC can therefore be a valuable tool in challenging diagnostic cases.