Pellegrini James R, Russe-Russe Jose R, Higgins Tate W, Prasandhan Shino, Khan Nausheer
Internal Medicine, Nassau University Medical Center, East Meadow, USA.
Gastroenterology, Nassau University Medical Center, East Meadow, USA.
Cureus. 2022 Jun 13;14(6):e25895. doi: 10.7759/cureus.25895. eCollection 2022 Jun.
Primary hepatic undifferentiated pleomorphic sarcoma (UPS) is a rare malignant mesenchymal tumor with a nonspecific clinical and radiologic presentation. Primary hepatic UPS is often a diagnosis of exclusion made by multiple immunohistological testing that rules out hepatic, hematologic, neural, and epithelial origin. Stains for mesenchymal origin are usually the only positive stain and do not demonstrate evidence of specific mesenchymal cell differentiation. We report a case of a 56-year-old male with no significant past medical history that presented with complaint of epigastric abdominal pain of six months duration. A computed tomography (CT) scan of the abdomen and pelvis exhibited numerous hepatic masses involving right and left hepatic lobe. A CT-guided core needle biopsy discovered undifferentiated/pleomorphic sarcoma. Histomorphology showed spindle cell neoplasm without recognizable hepatic tissue. Immunohistochemistry (IHC) stains were positive for smooth muscle actin (SMA) but failed to establish a more specific histogenesis. Furthermore, IHC stains revealed spindle neoplastic cells with focal and patchy positive h-caldesmon (approximately 10-15% of neoplastic cells), and negative for desmin. Given these results, the diagnosis of undifferentiated/pleomorphic sarcoma was established. It is imperative to consider UPS in the differential diagnosis of large liver lesions without evidence of differentiation. Early identification of this rare tumor can prevent the possibility of distant metastasis and improve survival among patients.
原发性肝未分化多形性肉瘤（UPS）是一种罕见的恶性间叶性肿瘤，具有非特异性的临床和影像学表现。原发性肝UPS通常是通过多项免疫组织化学检测排除肝、血液、神经和上皮来源后做出的排除性诊断。间叶来源的染色通常是唯一的阳性染色，且未显示出特定间叶细胞分化的证据。我们报告一例56岁男性，既往无重大病史，因上腹部腹痛6个月就诊。腹部和盆腔计算机断层扫描（CT）显示肝脏有许多肿块，累及左右肝叶。CT引导下的粗针活检发现未分化/多形性肉瘤。组织形态学显示为梭形细胞瘤，未见可识别的肝组织。免疫组织化学（IHC）染色平滑肌肌动蛋白（SMA）呈阳性，但未能确定更具体的组织发生。此外，IHC染色显示梭形肿瘤细胞h-钙调蛋白呈局灶性和斑片状阳性（约占肿瘤细胞的10-15%），结蛋白呈阴性。根据这些结果，确诊为未分化/多形性肉瘤。在鉴别诊断无分化证据的大肝脏病变时，必须考虑UPS。早期识别这种罕见肿瘤可预防远处转移的可能性并提高患者生存率。
