Figure 12c. Metastatic ovarian tumor with androgen-producing stroma in a 52-year-old woman. (a) Axial T2-weighted MR image shows a lobulated solid mass (arrows) with relatively low signal intensity adjacent to the uterus. The tumor does not seem to originate from the uterus, and no bridging vascular sign is noted. (b) Axial MR images obtained before (left) and 60 seconds after (right) contrast material administration show that the tumor enhances rapidly and strongly. This enhancing pattern eliminates the possibility of a fibroma. The patient had a history of advanced gastric cancer 3 years before the MR imaging examination. (c) Low-power photomicrograph (H-E stain) reveals signet ring cells (of the same histologic subtype as the formerly treated gastric cancer) strewn in small clusters within an ovarian stoma. The increased serum testosterone level (140.9 ng/dL [4.9 nmol/L]) normalized after surgery (12.5 ng/dL [0.4 nmol/L]).