Extensive Paneth cell metaplasia in an ovarian Krukenberg tumor: report of an unusual case and literature review.

Paneth cells are classified as secretory cells which are normally found in the cecum and ascending colon. Their presence in other parts of the gastrointestinal tract is regarded as abnormal and indicates metaplasia. Paneth cells may also be rarely found in gastrointestinal, biliary and prostatic tumors. The presence of Paneth cells in ovarian Krukenberg tumors is rare and to the best of our knowledge is restricted to metastatic appendiceal goblet cells tumors. We report a rare case of unilateral metastatic gastric carcinoma to the ovary in a 23-year-old female. This tumor showed unusual extensive Paneth cells metaplasia with classical signet ring cell morphology.