Undifferentiated Hepatic Sarcoma: A Rare Case

Abstract

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.

Ultrasonography, contrast-enhanced ultrasonography and contrast- enhanced computer tomography features of hepatic sarcomatoid carcinoma and hepatic sarcoma: a retrospective study of 23 cases

“…Pathological biopsy is currently the gold standard for distinguishing HS from HSC but it has some limitations: on the one hand, the ne needle biopsy usually failed to determine the nature of the mass due to its large size and insu cient samples. On the other hand, punctuation is an invasive surgical procedure that should not be repeated if the typical lesion is not obtained [19] . Preoperative diagnosis by imaging may prevent unwarranted diagnostic surgical procedures.…”