title: Hepatic falciform ligament clear cell myomelanocytic tumor: A case report and a comprehensive review of the literature on perivascular epithelioid cell tumors.
abstract: BACKGROUND
  The objective of the study was to explore the clinical expression, radiological and pathological features, differential diagnosis, and biological behavior of a clear cell myomelanocytic tumor. In a case involving a clear cell myomelanocytic tumor located in the hepatic falciform ligament, we evaluated clinical expression, radiological characteristics, histopathology, immunohistochemistry, and biological behavior; we also reviewed the relevant literature.
  
  
  METHODS
  Clear cell myomelanocytic tumor is a benign soft-tissue neoplasm that often occurs in women, and is expressed as a painless mass. The falciform ligament is its most frequent site of occurrence. The imaging characteristics of this lesion were uneven enhancement in the arterial phase, continuing to strengthen in the venous phase, and equal density in the balance phase. Histological and immunohistochemical analysis revealed the main transparent epithelioid cells and smooth muscle spindle cells to be HMB-45(+), smooth muscle actin(+), and melan-A (+).
  
  
  CONCLUSIONS
  Hepatic vascular epithelioid cell tumors are very rare mesenchymal neoplasms. Few studies have investigated this tumor in the hepatic falciform ligament; consequently, its diagnosis and the selection of an appropriate treatment and follow-up protocol are challenging. Treatment outcome remains unpredictable. Therefore, clear cell myomelanocytic tumor should be viewed as a tumor with uncertain malignant potential requiring long-term follow-up.
authors.affiliation: Department of Hepatobiliary Surgery, Affiliated Hospital of Qingdao University, Qingdao, Shandong, 266003, China. wangzusen@126.com.
authors.forename: Zu-Sen
authors.initials: ZS
authors.lastname: Wang
authors.affiliation: Department of Hepatobiliary Surgery, Affiliated Hospital of Qingdao University, Qingdao, Shandong, 266003, China. 176634159@qq.com.
authors.forename: Lin
authors.initials: L
authors.lastname: Xu
authors.affiliation: Department of General Surgery, Qingdao Eighth People's Hospital, Qingdao, Shandong, 266003, China. steward.ma@163.com.
authors.forename: Lin
authors.initials: L
authors.lastname: Ma
authors.affiliation: Department of Hepatobiliary Surgery, Affiliated Hospital of Qingdao University, Qingdao, Shandong, 266003, China. sihaiwuxin1007@163.com.
authors.forename: Meng-Qi
authors.initials: MQ
authors.lastname: Song
authors.affiliation: Department of Hepatobiliary Surgery, Affiliated Hospital of Qingdao University, Qingdao, Shandong, 266003, China. Wulq5810@126.com.
authors.forename: Li-Qun
authors.initials: LQ
authors.lastname: Wu
authors.affiliation: Department of Pathology, Affiliated Hospital of Qingdao University, Qingdao, Shandong, 266003, China. Zhouxian_35@163.com.
authors.forename: Xuan
authors.initials: X
authors.lastname: Zhou
mesh_terms: D000328:Adult; D014408:Biomarkers, Tumor / Q000378:metabolism; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D054973:Perivascular Epithelioid Cell Neoplasms / Q000378:metabolism / Q000473:pathology*
chemical_list: D014408:Biomarkers, Tumor