Bilateral ovarian enlargement may reflect benign or malignant processes of the ovary. Benign causes of ovarian enlargement include luteomas, tumors such as mature cystic teratomas, fibrothecomas, cystadenomas and rare conditions including capillary hemangioma and massive edema of the ovaries. Ovarian malignancies include epithelial, stromal and germ-cell tumors. Primary malignancies that may exhibit metastases to the ovaries include gastrointestinal, breast and soft tissue tumors such as lymphoma. We present an unusual case in which a patient presenting with weakness and mild lower abdominal and pelvic pain was noted at sonography to have bilaterally enlarged ovaries with features similar to those of massive ovarian edema as described previously, which has been associated with venous and lymphatic obstruction. Subsequent computerized tomography (CT) imaging depicted a large retroperitoneal tumor, CT-guided biopsy of which revealed diffuse large B cell lymphoma. The patient responded well to chemotherapy with significant shrinkage of the tumor, and reappearance of normal findings on ovarian sonography. This case demonstrates that bilaterally enlarged ovaries may be the first clinical evidence of a large retroperitoneal tumor and that in such cases CT imaging may be warranted. Copyright © 2007 ISUOG. Published by John Wiley & Sons, Ltd.