Carcinosarcoma of the Pancreas: Case Report With Comprehensive Literature ReviewRuess, Dietrich A. MD*; Kayser, Claudia MD†; Neubauer, Jakob MD‡; Fichtner-Feigl, Stefan MD*; Hopt, Ulrich T. MD*; Wittel, Uwe A. MD*Pancreas: October 2017 - Volume 46 - Issue 9 - p 1225–1233 doi: 10.1097/MPA.0000000000000904 Case Report Abstract Author Information Carcinosarcomas are rare biphasic neoplasms with distinct malignant epithelial and mesenchymal components. Most commonly, carcinosarcomas arise in the uterus as malignant mixed müllerian tumors, but also infrequently appear in other organs such as the ovaries and breast, the prostate and urinary tract, the lungs, or in the gastrointestinal system, among others. Pancreatic carcinosarcomas are exceedingly rare; only a few cases are reported in the English literature. Their pathogenesis remains to be fully clarified. We present here the case of a pancreatic carcinosarcoma with evidence for monoclonality via determination of Kras mutational status after microdissection and suggest a common origin of the 2 tumor components. Comprehensive review of the available literature allows the conclusion that most pancreatic carcinosarcomas appear to be of monoclonal origin and seem to have arisen from a carcinoma via metaplastic transformation of 1 part or subclone of the tumor, probably by epithelial-mesenchymal transition. All reported patients were treated with surgery. Adjuvant therapy, if administered, consisted predominantly of gemcitabine. Prognosis for this neoplasm occurs to be similar or even worse compared with classic pancreatic ductal adenocarcinoma. Despite the lack of evidence-based recommendations for its treatment, resection should be performed, if possible. From the *Department of Surgery, †Institute for Surgical Pathology, and ‡Department of Radiology, Faculty of Medicine, Medical Center–University of Freiburg, Freiburg, Germany. Received for publication November 16, 2016; accepted August 2, 2017. Address correspondence to: Dietrich A. Ruess, MD, Department of Surgery, Faculty of Medicine, University of Freiburg, Hugstetter Str. 55, 79106 Freiburg, Germany (e-mail: firstname.lastname@example.org). The authors declare no conflict of interest. Copyright © 2017 Wolters Kluwer Health, Inc. All rights reserved.