Sex cord tumor with annular tubules

These low and high magnification photos show a sex cord-stromal tumor known as the sex cord tumor with annular tubules. They are characterized by well-circumscribed epithelial islands which form tubules without lumens. They can be solitary or multicentric. Small multicentric tumors are often associated with Peutz-Jeghers syndrome. Patients with large solitary lesions often have elevated serum levels of progesterone, inhibin, and müllerian-inhibiting substance (MIS).

With thanks to Dr. Margaret Steinhoff