Intrahepatic Cholangiocarcinoma With Predominant “Ductal... : The American Journal of Surgical Pathology (original) (raw)

Original Articles

Intrahepatic Cholangiocarcinoma With Predominant “Ductal Plate Malformation” Pattern

A New Subtype

Nakanuma, Yasuni MD, PhD*; Sato, Yasunori MD, PhD*; Ikeda, Hiroko MD, PhD†; Harada, Kenichi MD, PhD*; Kobayashi, Mikiko MD‡; Sano, Kenji MD, PhD‡; Uehara, Takeshi MD, PhD‡; Yamamoto, Masakazu MD, PhD§; Ariizumi, Shunichi MD§; Nyun Park, Young MD, PhD∥; Choi, Joon Hyuk MD, PhD¶; Yu, Ensil MD, PhD#

*Department of Human Pathology, Kanazawa University Graudate School of Medicine

†Diagnostic Pathology Section, Kanazawa University Hospital, Kanazawa

‡Department of Pathology, Shinshu University School of Medicine, Matsumoto, Nagano

§Department of Surgery, Tokyo Women’s Hospital, Tokyo, Japan

∥Department of Pathology, Yonsei University School of Medicine, Seoul

#Department of Pathology, Asan Medical Center, Medical College of Ulsan, Seoul

¶Department of Pathology, Yeungnam University College of Medicine, Daegu, Korea

Conflicts of Interest and Source of Funding: The authors have disclosed that they have no significant relationships with, or financial interest in, any commercial companies pertaining to this article.

Correspondence: Yasuni Nakanuma, MD, PhD, Department of Human Pathology, Kanazawa University Graduate School of Medicine, Kanazawa 920-8640, Japan (e-mail: [email protected]).

Abstract

Ten cases of intrahepatic cholangiocarcinoma showing a highly differentiated adenocarcinoma mimicking ductal plate malformation (DPM) are reported. The patients included 7 males and 3 females with an average age of 69.5 years. Six cases were associated with chronic liver disease and the remaining 4 cases showed mild fatty change in the parenchyma and/or minimal to mild portal inflammation. Grossly, the tumor was a single nodule 1.5 to 6.6 cm in diameter, and was whitish and solid without a fibrous capsule. Microscopically, the tumor was composed of many vague, small nodular carcinomatous areas with desmoplastic reactions, and neoplastic glands had an irregularly dilated lumen lined with a single layer of cuboidal or low columnar carcinoma cells and irregular protrusions and bulges, resembling DPM. At its border, the carcinoma seemed to replace the non-neoplastic hepatic lobules or regenerative nodules. The central parts of the tumor were variably hypocellular and fibrotic. Although these carcinomas were negative for mucin and HepParI, they were frequently positive for CK19, epithelial cell adhesion molecule, and epithelial membrane antigen. Neural cell adhesion molecule was also expressed variably. The Ki-67 labeling index was <10% and p53 was scarcely expressed. In conclusion, a new subtype of intrahepatic cholangiocarcinoma with predominant DPM pattern was identified.