Brenner tumor

Brenner tumor (Brenner carcinoma, ICD-O: ) is a mixed ovarian fibroepithelial tumor. It is a relatively rare tumor, it represents about 2% of all ovarian tumors, 71% of cases are demonstrated in people over the age of 40. It is mostly a benign tumor, but borderline and malignant variants can also occur. Although it is an ovarian tumor, it can rarely occur in other locations, especially in other areas of the female genital tract. The Brenner tumor itself can rarely be the target of the metastatic process

The actual histogenetic origin of Brenner's tumor is not a closed question, most authors assume that the tumor originates from the surface epithelium of the ovaries, which metaplastically changes into urothelium.

Benign Brenner tumor
ICD-O:

Benign Brenner tumor is the most common variant of Brenner tumor. It represents 4 to 5% of benign ovarian tumors, usually diagnosed in women between 30 and 60.

Macroscopic appearance
Macroscopically, Brenner's tumor is relatively dense, solid, and similar to fibroma. It tends to have well-defined border and the usual size at diagnosis is 2 cm, only 10% of cases are over 10 cm in diameter. In section, the structure is relatively fine-grained, white to yellow in color. Deposits of calcification may be present, and the presence of cysts is quite common. Association with another tumor, especially mucinous cystadenoma, is not rare.

Histological appearance
The epithelial component is represented by not quite regular nests or stripes of light, sharply demarcated polygonal cells characteristic of urothelium (transitional epithelium). The nucleus of these cells has a central groove that gives it the appearance of a coffee bean character. Cytoplasm is abundant, bright. Nests may have a central cavity in which eosinophilic material then accumulates, staining with mucin. In addition to the morphological ones, the epithelial component shows some immunochemical characteristics similar to the urothelium (urothelin expression), but others are absent (thrombomodulin expression) or have only been demonstrated inconsistently (cytokeratin 20 expression).

The stroma is relatively cellular, clearly mesenchymal character. It sharply borders individual nests of epithelial cells. The stroma can undergo luteinization and then it is very likely capable of producing sex hormones.

Clinical behavior
Most benign Brenner tumors are asymptomatic, only greatly enlarged tumors may present nonspecifically as a mass in the small pelvis. The stromal component can sometimes undergo focal luteinization, and the tumor can then manifest itself as an overproduction of sex hormones. Ascites appears only rarely.



Border-line Brenner tumor
ICD-O:

A border-line tumor already shows atypia in the epithelial component compared to a benign tumor, but there is no demonstrable stromal invasion. It represents about 3 to 5% of all diagnosed Brenner tumors.

Macroscopic appearance
A border-line is usually quite large at the time of diagnosis, typically measuring 16–20 cm in diameter. It usually contains components similar to a benign Brenner tumor and foci of a cystic component in which papillary or polypoid masses may be present. Bilateral occurrence is rare.

Histological appearance
The structure of the tumor is richer, the fibrovascular stroma can lead to the rise of a papillary structure. The mitotic activity of the epithelial component is variable but may be substantial. Focal necrosis and mucinous metaplasia, which can sometimes dominate the entire picture, are relatively common.

Clinical behavior
The tumor presents clinically as masses in the small pelvis or abdominal pain, sometimes it can be the cause of abnormal vaginal bleeding. Not a single case of metastatic spread or even death has been described in a patient with Brenner tumor, without stromal invasion, only local recurrence is at risk.

Malignant Brenner tumor
ICD-O:

V případě maligního Brennerova tumoru se maligně chová epiteliální složka. Tumor obvykle obsahuje i ložiska benigního Brennerova tumoru. Maligní varianta představuje asi 5 % všech Brennerových tumorů. Nejčastěji se vyskytuje u žen ve věku 50 až 70 let.

Makroskopický vzhled
Vzhledem je maligní Brennerův tumor podobný border-line tumoru. V době diagnózy má obvykle průměr 16–20 cm, na řezu obsahuje solidní komponentu i cystické formace. Do cyst mohou vyrůstat nádorové hmoty v podobě papilárních až polypózních formací. Oboustranné postižení se vyskytuje u 12 % případů.

Histologický obraz
Histologický obraz obvykle zachycuje benigní nebo border-line tumor, ve kterém je přítomna komponenta invadující do stromatu. Invazivní komponenty jsou obvykle charakteru high-grade nádoru z přechodných buněk nebo dlaždicobuněčného karcinomu. Mohou být přítomny i glandulární a mucinózní struktury. Bývají přítomna ložiska kalicifikace, v některých případech může kalcifikace dominovat histologickému obrazu. Někdy může být mucinózní metaplazie tak výrazná, že se jsou struktury Brennerova tomoru jen velmi málo patrné a lze je snadno přehlédnout.

Klinické chování
Klinické projevy bývají stejné jako u border-line tumoru, tedy projevy přítomnosti nádorové hmoty v malé pánvi, bolesti břicha a někdy i abnormální vaginální krvácení.

80 % maligních Brennerových tumorů je zachyceno ve stádiu I. Pětileté přežití pacientů ve stádiu IA je 88 %.

Externí odkazy

 * Brenner tumors - general na webu PathologyOutlines.com
 * Benign Brenner tumor na webu PathologyOutlines.com
 * Borderline Brenner tumor na webu PathologyOutlines.com
 * Malignat Brenner tumor na webu PathologyOutlines.com