Expression of Brn-3a(l) in grades 1, 2 and 3 ovarian tumors. (a) Grade 1 mucinuous; (b) grade 1 endometriod; (c) grade 2 serous; (d) grade 3 serous and (e) grade 3 clear cell carcinoma tumors. Long arrows in each tumor illustrate positive Brn-3a(l) staining of the scattered epithelium. Short arrows in (d) and (e) indicate scattered stromal staining. Magnification-400; scale = 50 μm.