title: Enlarged solitary necrotic nodule of the liver misinterpreted as a metastatic liver cancer.
abstract: Solitary necrotic nodule of the liver is a rare nonmalignant lesion of unknown etiology. It is defined as a nodule with a completely necrotic core enclosed by a hyalinized fibrotic capsule containing elastic fiber. We report a 74-year-old woman with a solitary necrotic nodule of the liver that mimicked metastasis from a previous rectal adenocarcinoma. She was referred to us for an asymptomatic liver nodule in segment 8 that had increased in diameter from 5 to 15 mm over the past 8 months. Ultrasonography showed a well-defined, oval, hypoechoic mass, and computed tomography showed a hypodense area without contrast enhancement except for a ring-like enhancement during hepatic arteriography. Magnetic resonance imaging revealed a mass that was hypointense on T1-weighted imaging and slightly hyperintense on T2-weighted imaging. The patient underwent hepatectomy of segment 8. The resected specimen contained an oval nonencapsulated nodule with firm and gritty consistency and a well-defined margin. Histologic findings were compatible with those of solitary necrotic nodule. Clinicians should recognize the existence of this lesion as one of the differential diagnoses of metastatic liver nodule. Solitary necrotic nodules can change size, and when enlarged, differentiation from metastasis is extremely difficult.
authors.affiliation: Department of Surgical Oncology and Regulation of Organ Function, Miyazaki University School of Medicine, 5200 Kihara, Kiyotake, Miyazaki, 889-1692, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Otani
authors.affiliation: Department of Surgical Oncology and Regulation of Organ Function, Miyazaki University School of Medicine, 5200 Kihara, Kiyotake, Miyazaki, 889-1692, Japan. kazuochi@med.miyazaki-u.ac.jp.
authors.forename: Kazuo
authors.initials: K
authors.lastname: Chijiiwa
authors.affiliation: Department of Surgical Oncology and Regulation of Organ Function, Miyazaki University School of Medicine, 5200 Kihara, Kiyotake, Miyazaki, 889-1692, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Kondo
authors.affiliation: Department of Surgical Oncology and Regulation of Organ Function, Miyazaki University School of Medicine, 5200 Kihara, Kiyotake, Miyazaki, 889-1692, Japan.
authors.forename: Mai
authors.initials: M
authors.lastname: Tsuchimochi
authors.affiliation: Department of Surgical Oncology and Regulation of Organ Function, Miyazaki University School of Medicine, 5200 Kihara, Kiyotake, Miyazaki, 889-1692, Japan.|Department of Pathology, Miyazaki University School of Medicine, Miyazaki, Japan.
authors.forename: Nobuyasu
authors.initials: N
authors.lastname: Takahashi
authors.affiliation: Department of Surgical Oncology and Regulation of Organ Function, Miyazaki University School of Medicine, 5200 Kihara, Kiyotake, Miyazaki, 889-1692, Japan.
authors.forename: Naoki
authors.initials: N
authors.lastname: Ikenaga
authors.affiliation: Department of Surgical Oncology and Regulation of Organ Function, Miyazaki University School of Medicine, 5200 Kihara, Kiyotake, Miyazaki, 889-1692, Japan.
authors.forename: Jiro
authors.initials: J
authors.lastname: Ohuchida
authors.affiliation: Department of Pathology, Miyazaki University School of Medicine, Miyazaki, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Tanaka
authors.affiliation: Department of Pathology, Miyazaki University School of Medicine, Miyazaki, Japan.
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Kataoka
keywords: Liver; Metastasis; Necrotic nodule