Expression of p53 in inverted papilloma and malignancy associated with inverted papilloma

Objective: To determine the association of p53 protein in malignant cases of inverted papilloma compared with cases of benign inverted papilloma of the sinonasal tract. Design: Case-control study of archived pathologic material. Setting: Tertiary care hospital. Methods: Archived pathologic material of cases of malignancy associated with inverted papilloma and controls of benign inverted papilloma were obtained from Mount Sinai Hospital. These were subjected to immunohistochemistry for p53. Clinical correlation was obtained by retrospective chart review. Main Outcome Measures: Staining of pathologic specimens for p53 and survival or recurrence. Results: Four of the five cases of malignancy associated with inverted papilloma demonstrated overexpression of p53. None of the benign cases of inverted papilloma demonstrated overexpression. Only two of the five patients with malignancy associated with inverted papilloma were alive at 2 years. Conclusions: Overexpression of p53 may serve as a marker for malignant transformation of inverted papilloma.