Figure 1

ARID1A immunoreactivity in two representative ovarian clear-cell carcinoma cases. (a) A clear-cell carcinoma showing diffuse and strong nuclear immunoreactivity for ARID1A. (b) A clear-cell carcinoma with undetectable ARID1A immunoreactivity. Stromal cells of both the samples show moderate to strong immunoreactivity and serve as internal positive controls. The carcinomas shown in panels a and b were defined as ARID1A-intact and ARID1A-deficient carcinomas, respectively. Immunoperoxidase stain, original magnification × 200 for (a) and × 400 for (b).