Fig. 1

Histopathology of the poorly differentiated mucinous carcinoma with signet ring cells of the ovary. The small carcinomatous nodule is continuous with the epithelium of the endometriotic cyst [a, b]. The tumor cells arranged in solid nests with occasional cribriform structure and crowded small neoplastic glands with marked nuclear atypia [c, d]. Signet ring cell carcinoma can be frequently seen [c, e]. The cytoplasmic mucin of the tumor cells is Alcian Blue positive [f]. Atypical surface epithelium in the endometriotic cyst exhibits cellular stratification, small papillation and variable cytological atypia [g, h]. Original magnifications: a × 50; b, d, f, g × 200; c × 100; e, h × 400