Metastatic Gallbladder Carcinoma to the Ovary Presenting As Small Bowel Obstruction

The ovaries are a common site of metastasis from different organs, especially from the gastrointestinal tract. However, metastasis from the gallbladder to the ovaries is very rare. Our case involves a 57-year-old female who presented with abdominal pain and distension. Radiologic imaging suggests the possibility of a primary ovarian tumor causing small bowel obstruction. Grossly, the cystic mass in the right ovary closely resembles the typical characteristics of a primary ovarian tumor. Histologic examination revealed adenocarcinoma. Positive immunostaining for CA 19-9, cytokeratin-7 (CK7), CEA, and CDX2 and negative reaction to CK20, PAX8, and CA 125 are compatible with a pancreaticobiliary/gallbladder origin. Considering the results obtained from imaging, which included gallbladder wall thickening and the presence of a mass within the gallbladder, alongside the pancreas appearing normal, the primary site of concern was determined to be the gallbladder. It is important to consider primary sites other than the ovary in the presence of previous or concurrent lesions elsewhere, such as gastrointestinal (GI) or pancreaticobiliary tract since treatment regimens are different. Clinicoradiologic correlation and immunohistochemistry aid in differentiating this secondary ovarian tumor from a primary ovarian carcinoma.