%0 Journal Article %T A Case of Solitary Necrotic Nodule Treated with Laparoscopic Hepatectomy: Spontaneous Regression of Hepatocellular Carcinoma? %A Hirokazu Tomishige %A Zenichi Morise %A Yoshikazu Mizoguchi %A Norihiko Kawabe %A Hidetoshi Nagata %A Hisanori Ohshima %A Jin Kawase %A Satoshi Arakawa %A Rie Yoshida %A Masashi Isetani %J Case Reports in Hepatology %D 2013 %I Hindawi Publishing Corporation %R 10.1155/2013/723781 %X Solitary necrotic nodule of the liver is a rare benign lesion with a completely necrotic core and a hyalinized fibrotic capsule containing elastic fibers. The pathogenetic mechanism is still unclear. We here describe a case of SNN, whose central reticulin fibers within the nodule suggest the origin as hepatocellular carcinoma or other hepatocyte-origin tumors, treated with laparoscopic anatomical segmentectomy of the liver. A 76-year-old Japanese female, with no prior medical history and no symptom, visited our hospital with the heterogeneous hypoechoic lesion in the liver segment VI incidentally pointed out in abdominal ultrasonography. Computed tomography with contrast demonstrated a 1.1 cm sized low-density lesion with mild ring enhancement on the rim in the arterial phase. Since the possibility of malignant tumor with necrotic change could not be ruled out, she underwent laparoscopic anatomical segmentectomy of the liver. In the histological examination of the surgical specimen, the liver nodule was necrotic tissue without viable cells and signs of inflammation, which had fibrous capsule and central cystic change and showed trabecular pattern alignment of ghost cells and reticulin fibers orthogonal to the capsule. Also, the findings of chronic hepatitis were observed in the background liver. 1. Introduction Solitary necrotic nodule (SNN) of the liver is a rare benign lesion first reported in 1983 by Shepherd and Lee, who described four lesions with a completely necrotic core and a hyalinized fibrotic capsule containing elastic fibers [1]. The pathogenetic mechanism is still unclear. In their original study, Shepherd and Lee favored traumatic or infectious etiology [1]. Sundaresan et al. showed the presence of the feeding vessels within the nodule suggesting hemangiomatous origin. They also described central reticulin fibers within the nodule, suggesting the origin as sclerosing hemangioma [2]. We here describe a case of SNN, whose central reticulin fibers within the nodule suggest the origin as hepatocellular carcinoma (HCC) or other hepatocyte-origin tumors, treated with laparoscopic anatomical IV segmentectomy of the liver. 2. Case Presentation A 76-year-old Japanese female, with no prior medical history and no symptom, visited our hospital with the heterogeneous hypoechoic lesion in the liver segment VI incidentally pointed out in abdominal ultrasonography (US). There were no abnormal findings in her routine laboratory data, including liver function tests, serology profile for hepatitis B or C, and tumor markers including CA 19-9, %U http://www.hindawi.com/journals/crihep/2013/723781/