“…Immunohistochemical studies may facilitate diagnosis of these lesions, given that Ki-67, PCNA and p53 were found expressed at higher levels within the sarcomatous component of the AFS, whereas they are absent or expressed at lower levels in AF (5,12,62,69,79,89,101,113,123). Results obtained from several papers (4,5,69,79,82,88,89,113) revealed that Ki-67 was overexpressed (highly diffuse positivity) in the malignant mesenchymal portion of AFS, compared with AF.…”