Which statement best describes serous cystadenoma?

• A. It is the second most common benign ovarian neoplasm
• B. It is a malignant germ cell tumor
• C. It commonly causes pleural effusion
• D. It arises from granulosa cells

Answer: (A)

Serous cystadenoma is a benign epithelial tumor of the ovary, typically presenting as a cystic mass lined by serous-type epithelium. Among benign ovarian neoplasms, mature cystic teratoma is the most common, and serous cystadenoma is the second most common, which is why this statement is best. It is not a malignant germ cell tumor, it does not arise from granulosa cells (that would be a granulosa cell tumor), and pleural effusion is not a characteristic feature of serous cystadenoma (Meigs syndrome involves an ovarian fibroma, ascites, and pleural effusion, not a serous cystadenoma).