IMMUNOHISTOCHEMICAL NUCLEAR STAINING FOR P53, PCNA, AND KI-67 IN DIFFERENT HISTOLOGIC VARIANTS OF BASAL-CELL CARCINOMA

Background: Increased expression of p53 has been found in the majority of basal cell carcinomas (BCCs); however, UV-light-induced signature mutations are present in only about 50% of eases. Increased nuclear st aining with an immunohistochemical marker of proliferation, proliferat ing cell nuclear antigen (PCNA), has been correlated with aggressive b ehavior in BCC. Objective: Our purpose was to determine whether there is any relationship between different histologic variants of BCC and, their expression of p53, PCNA, and Ki-67. Methods: We used immunohisto chemical stains for p53, PCNA, and Ki-67, in superficial-multicentric, nodular-noduloulcerative, sclerosing, infiltrative, and metatypical B CC, to determine whether the staining patterns differ in these differe nt histologic variants of BCC. Results: Superficial-multicentric BCCs were negative for p53 in four of eight tumors. Nodular BCC showed mode rately intense p53 nuclear staining with some peripheral accentuation. PCNA nuclear staining was greater than Ki-67, and PCNA-positive cells were fewer than 10% in nodular BCC. Sclerosing and infiltrative BCC s howed intense p53 nuclear staining with peripheral accentuation, PCNA nuclear staining was greater than Ki-67, and PCNA-positive cells were greater than 30% in the majority of these tumors. Metatypical BCCs sho wed diffuse intense p53 staining. PCNA nuclear staining was greater th an Ki-67, and PCNA-positive cells were greater than 30% in all tumors studied, When overlying actinic keratoses showed p53 staining, the sta ining did not necessarily correlate with the intensity or even the pre sence of positive staining in the subjacent BCC. Conclusion: There are at least four distinctive patterns for staining of p53, PCNA, and Ki- 67 that correlate with different histologic variants of BCC.