The inner surface of this tumor contains a few clusters of broad-based papillae in an otherwise smooth lining.
In this gross example, you can see the solid fibrous component attached to the collapsed thin-walled serous lining.
Broad based papillae with fibrous cores are lined by a simple epithelial layer.
Some of the papillae project into a cystic space -- note that there is no stratification of the epithelium.
A close view of the lining reveals ciliated cells resembling those lining the fallopian tubes. There should be minimal to absent tufting and nuclear atypia.
In this example, small glandular structures are scattered within the dense ovarian stroma.
Serous tumors of the tumor are characterized by epithelial cells that recapitulate the lining of the fallopian tube. Benign serous tumors comprise approximately 50% of serous tumors of the ovary, with borderline serous tumors (15%) and malignant serous tumor (35%) comprising the other half.1
Grossly, the tumor may be unilocular or multilocular, lined by thin smooth walls. Small papillary excrescences may occasionally be found in the lining. Microscopically, the lining epithelial cells resemble the ciliated and secretory cells found in the fallopian tube. The nuclei are basally oriented with uniform ovoid shapes. The lining may be attenuated if the cystic contents create pressure on the cells.1,2
A note on terminology:
When fibrous stroma occupies an area greater than the cystic portion, the suffix “-fibroma” is added, as in “serous adenofibroma.” The presence of more than a cyst over 1 cm in diameter warrants use of the prefix “cyst,” as in “cystadenofibroma.” Cystadenofibromas may mimic malignancy by imaging because they may appear as multilocular cystic masses with solid components.
Affects reproductive age women. They are bilateral in 20% of cases. Usually asymptomatic and incidentally found. Rare complications include torsion or rupture.
Surgical excision via oophorectomy or cystectomy is curative as these tumors are benign.
1 Nucci MR, Oliva Esther. Gynecologic Pathology: Foundations in Diagnostic Pathology. Philadelphia, PA: Elsevier: 2009: 395-8.
2 Fletcher CDM, ed. Diagnostic Histopathology of Tumors. 3rd Ed. Philadelphia, PA: Elsevier; 2007: 570.