Proliferating cell nuclear antigen (PCNA) expression in B-cell lymphomas and pseudo-B-cell-lymphomas of the skin

Abstract

Differentiation of cutaneous B-cell lymphomas and pseudo-B-cell lymphomas of the skin is a diagnostic challenge in histopathology. The aim of this study was to evaluate the reproducibility of PCNA index in the differential diagnosis of primary cutaneous B-cell lymphomas and pseudo-B-cell lymphomas of the skin. To assist in diagnosis, scoring of proliferating cell nuclear antigen index was performed on specimens previously diagnosed as cutaneous B-cell lymphomas (n: 20) and pseudo-B-cell lymphomas (n: 18) in skin biopsies. By using a projection microscope the measurements were carried out in 10 to 12 high power fields at a final magnification x2500 for each representative slide. In each specimen at least 1000 cells were counted with a transparent overlay system composed of 100 squares. Our results showed a significant difference in PC10 indices between the cutaneous B-cell lymphomas (36.27± 17.35%) and pseudo-B-cell lymphomas (15.69 ± 4.81%). In conclusion, we suggest that the detection of proliferating cell nuclear antigen indices could be valuable, useful and supportive in differential diagnosis of benign and malignant cutaneous B-cell lymphoid infiltrates of the skin.