Extracapsular Hepatocellular Adenoma: A Diagnostic Dilemma
benign tumor, liver, diagnosis, lesions, pathological examination
Digestive System | Gastroenterology | Internal Medicine | Medicine and Health Sciences
Introduction: Hepatocellular adenoma (HCA) is a benign tumor of the liver and almost always located intracapsular. Bleeding (25%), and malignant transformation (5%) can complicate the disease course if left untreated. Herein, we present a case of extracapsular HCA of ectopic liver in the omentum complicated with intraperitoneal hemorrhage.
Case Description/Methods: A 43-year-old lady with no past medical history presented to emergency department with two-day history of left shoulder pain and epigastric discomfort. Her only medication was an oral contraceptive pill (OCP). On physical exam, the patient had persistent sinus tachycardia, and epigastric tenderness. Initial labs were unremarkable except for mildly elevated AST at 58 IU/L (10-37). CT of the abdomen with IV contrast showed a heterogeneously enhancing mass likely arising from the anterior wall of the stomach. T2-weighted MRI abdomen demonstrated a hypoenhancing mass measuring 4 x 7 x 8 cm with adjacent hemorrhage (Image 1). Exploratory laparotomy revealed an infarcted, hemorrhagic mass between the fundus of the stomach, spleen, and diaphragm with a large amount of clots and free blood occupying the greater curvature. The mass was separated from surrounding viscera however, slightly attached to the diaphragm. The mass was removed with the completely resolved tachycardia and epigastric pain postoperatively. Initially, the lesion was thought to be an accessory spleen based on location and gross examination. Microscopically, an infarcted, hemorrhagic mass composed of cords of degenerated epithelioid cells with vacuolated cytoplasm was surrounded by reactive fibro- and myofibroblastic tissue. Epithelioid cells were diffusely stained for HerPar-1 (hepatocyte origin), and CK AE1/AE3 (image 2). These findings were consistent with HCA.
Discussion: HCA is an overlooked diagnosis and can result in serious complications if unrecognized. Among the well-known risk factors of HCA are OCPs or anabolic steroids, pregnancy, and steatohepatitis. The prevalence of these lesions has been rising parallel to increasing use of OCP and abdominal imaging. In females, lesions < 5cm with no associated symptoms or complications can be managed conservatively by terminating OCP use, and surveillance. Our patient presented with acute left shoulder pain which was likely due to phrenic nerve irritation by bleeding (Kehr’s sign). To best of our knowledge, there are only three cases of extracapsular HCA reported in the English literature.
Image 1: T2 weighted MRI of the abdomen demonstrated a hypoenhancing exophytic mass arising from the anterior wall of the stomach measuring 4 x 7 x 8 cm in maximum anteroposterior, transverse, and craniocaudal dimensions (arrow). (A) transverse view, (B) coronal view. Image 2: Histopathological examination showing an infarcted, hemorrhagic mass composed of cords of degenerated epithelioid cells with vacuolated and occasionally lipid-laden cytoplasm. (A) A large, dilated vessel with thrombi (B) and papillary endothelial hyperplasia were demonstrated. The mass was surrounded by reactive fibro- and myofibroblastic tissue (C). Epithelioid cells were stained positive with pan-keratin CK AE1/AE3 (D).
Isin Comba indicated no relevant financial relationships. Richard Henriquez indicated no relevant financial relationships. Sundeep Kumar indicated no relevant financial relationships. Ruthvik Srinivasamurthy indicated no relevant financial relationships. Maria Wallis-Crespo indicated no relevant financial relationships. Olga Karasik indicated no relevant financial relationships. Lakhinder Bhatia indicated no relevant financial relationships.
Publisher or Conference
Comba IY, et al. P2545 - Extracapsular Hepatocellular Adenoma: A Diagnostic Dilemma. American College of Gastroenterology 2019 Annual Scientific Meetings; October 29, 2019; San Antonio, TX.