High-grade serous carcinoma

(A) High-grade serous carcinoma is composed of cells with pleomorphic nuclei and numerous mitotic figures as seen here (400x hematoxilin and eosin staining).
(B) In most high-grade serous carcinomas, p53 immunohistochemical staining is diffusely and strongly positive. However, a subset of high-grade serous carcinomas are negative for p53 immunohistochemical staining.