Neuroendocrine Cells as a Component of Ovarian Brenner Tumors: The Source of Rare Ovarian Carcinoid Tumors Associated with These Neoplasms
ED Euscher, A Malpica. MD Anderson Cancer Center, Houston, TX
Background: Ovarian Brenner tumors (OBT) are a subtype of ovarian surface epithelial neoplasm and may be associated with other tumors within this group, especially mucinous tumors. The association of OBT and ovarian carcinoid is exceedingly rare and has raised the possibility of a germ cell origin for some cases of OBT. Up to 40% of OBTs have been reported to contain <10% of non proliferating argyrophylic cells by the Grimelius technique; however, no contemporary study has evaluated the presence of neuroendocrine cells in OBT. After encountering a case of carcinoid tumor arising in continuity with an OBT, we undertook this study to ascertain if neuroendocrine cells represent a normal component of OBT, providing a possible explanation for the presence of a carcinoid associated with OBT.
Design: Twenty-nine cases (index case included) of OBT were retrieved from the files of the Department of Pathology at our institution over a 15 year period. The presence or absence of an associated surface epithelial component was noted. Immunostudies utilizing the standard avidin-biotin technique were performed as follows: chromogranin (CG), 20 cases; synaptophysin (SYN), 17 cases.
Results: Of the twenty-nine OBTs, thirteen had an associated surface epithelial tumor as follows: 9 mucinous cystadenomas , 1 mucinous tumor of low malignant potential , 2 serous cystadenomas, and 1 mixed serous/mucinous cystadenoma . None of the non index cases had an associated carcinoid tumor or evidence of neuroendocrine differentiation. The immunoperoxidase studies are summarized in Table 1.
Summary of Neuroendocrine Marker Expression in Ovarian Brenner Tumor
|Negative|| 10 cells||11-25 cells||26-50 cells||> 50 cells|
The index case had the highest number of CG + and SYN+ cells with most positive cells in the associated carcinoid tumor and in nests immediately adjacent to the carcinoid. Positive cells in the non index cases were present as isolated, single cells randomly distributed at the base of occasional OBT cell nests.
Conclusions: Non proliferative neuroendocrine cells may be a normal component of OBT. Rarely, this proliferation may result in small carcinoid tumors. Awareness of this phenomenon will allow the correct identification of these cases. The association of other tumor types with OBT is common, and carcinoid tumor may be included with this group. Carcinoid tumor, when associated with OBT, is likely primary in the ovary.
Wednesday, March 11, 2009 9:30 AM
Poster Session V # 130, Wednesday Morning