Pancreatic metastasis of an ovarian malignant mixed Mullerian tumor identified by EUS-guided fine needle aspiration and Trucut needle biopsy.

Background: Malignant mixed Mullerian tumors are rare ovarian neoplasms that account for less than 2% of ovarian malignancies. They have a generally poor prognosis and often develop recurrent disease. To our knowledge, this is the first report of a malignant mixed Mullerian tumor with metastasis to the pancreas. The metastatic tumor was identified by endoscopic ultrasound guided fine needle aspiration (EUS-FNA) and Trucut needle biopsy of the pancreas.

Methods: We describe a 69-year-old female with concomitant Duke's C adenocarcinoma of the colon and stage III-C malignant mixed Mullerian tumor that presented with malignant ascites, increasing abdominal girth and a pancreatic head mass. EUS revealed an 11 cm cystic mass in the head of the pancreas that was characterized as a carcinosarcoma/malignant mesodermal mixed tumor by EUS-FNA and Trucut needle biopsy. The tumor was morphologically identical to the surgical specimen of her ovarian mass. The patient was treated with palliative chemotherapy and a three-month follow up CT scan did not reveal any new metastatic lesions.

Conclusions: The pancreas is a rare site of metastasis and more commonly seen in renal cell carcinoma, melanoma or lung tumors; amongst others. Although ovarian adenocarcinoma has been reported as a primary site of pancreatic metastasis, it has not been previously described originating from a mixed Mullerian tumor of the ovary presenting as a cystic pancreatic head mass.