Embryonal (undifferentiated) sarcoma of the liver with peripheral angiosarcoma differentiation arising in a mesenchymal hamartoma in an adult patient

Primary malignant vascular tumors of the liver in children: Angiosarcoma and epithelioid hemangioendothelioma

Primary malignant vascular neoplasms of the liver, angiosarcoma and epithelioid hemangioendothelioma, are extremely rare entities in the pediatric population. International Society for the Study of Vascular Anomalies classification system is recommended for the pathologic diagnosis of hepatic vascular lesions in this age group. In this article, we highlight the clinicopathologic characteristics of hepatic angiosarcoma and epithelioid hemangioendothelioma in the pediatric population. Hepatic angiosarcoma in children shows a slight female predominance with an average age of 40 mo at diagnosis. The distinct histologic features include whorls of atypical spindled cells and eosinophilic globules, in addition to the general findings of angiosarcoma. Histologic diagnosis of pediatric hepatic angiosarcoma is not always straightforward, and the diagnostic challenges are discussed in the article. Hepatic epithelioid hemangioendothelioma also demonstrates a female predominance, but is more commonly identified in adolescents (median age at diagnosis: 12 years). Histologically, the lesion is characterized by epithelioid cells and occasional intracytoplasmic lumina with a background of fibromyxoid stroma. While WWTR1-CAMTA1 and YAP1-TFE3 fusions have been associated with epithelioid hemangioendothelioma, there are currently no known signature genetic alterations seen in pediatric hepatic angiosarcoma. Advancement in molecular pathology, particularly for pediatric hepatic angiosarcoma, is necessary for a better understanding of the disease biology, diagnosis, and development of targeted therapies.

Undifferentiated embryonal sarcoma of the liver in adults: Retrospective analysis of a case series and systematic review

Adult undifferentiated embryonal sarcoma of the liver (UESL) is an aggressive malignant tumor. As UESL is rare, the literature predominantly includes case reports, with a limited number of small case series. The aim of the present study was to investigate the presentation, treatment modalities and outcomes of this rare tumor. The present study includes a case series of adult UESL and a systematic review. A single-institution case series of adult UESL were retrospectively analyzed, and a systematic review of adult UESL was performed by searching MEDLINE, Web of Science, EMBASE, the Google Scholar database and the Cochrane Library. For all identified adult UESL cases, the demographic variables, treatments and survival were analyzed. Three female adult patients with UESL (median age, 21 years) were successfully treated by complete tumor resection, with or without adjuvant chemotherapy, at Beijing Tsinghua Changgung Hospital between 2015 and 2018. Of these patients, two are currently alive (follow-up, 9 and 41 months), and one died after pulmonary recurrence 17 months post-diagnosis. The present systematic review identified 108 cases of adult UESL. Among all 111 analyzed cases, the median overall and disease-free survival rates were as follows: 1-year, 72 and 67%; 3-year, 56 and 40%; and 5-year, 47 and 35%, respectively. Treatment strategies combining complete tumor resection and chemotherapy promoted improved overall and disease free survival time compared with radical tumor resection alone. The present analysis included one of the largest case series of UESL in adults, and is the first such study to present survival rates. The results of the present study confirmed that survival was improved by treatment strategies combining complete tumor resection and chemotherapy.

Hepatic mesenchymal hamartoma and undifferentiated embryonal sarcoma of the liver: a pathologic review

This review highlights two rare entities that are predominantly seen in children: hepatic mesenchymal hamartoma (HMH) and undifferentiated embryonal sarcoma of the liver (UESL). HMH is a benign lesion predominantly seen in the first 2 years of life, while UESL is malignant and usually identified in patients between 6 and 10 years of age. UESL may arise in the background of HMH, and the association has been supported by similar chromosomal aberrations (19q13.4). The diagnosis of both lesions is primarily based on histologic evaluation, as the clinical and radiological features are not always typical. The clinicopathologic characteristics, pathogenesis, differential diagnoses and treatment for both lesions are discussed.

Mesenchymal Hamartoma of the Liver in Older Children: An Adult Variant or a Different Entity? Report of a Case With Review of the Literature

Mesenchymal hamartoma of the liver (MHL) is an uncommon benign hepatic tumor typically affecting children under 2 years of age. Only 5% of MHL occur after 5 years and are very rarely observed in adults. According to age, MHL may differ in their morphologic features. We report a case of an 11-year-old boy with MHL, resembling a malignant lesion from a clinical point of view, characterized by unusual histologic features: a prominent myxoid stroma, with a minimal ductular component, and absent cystic spaces. The present case and others reported in older children or adults demonstrate that these lesions may represent a potential diagnostic pitfall when occurring outside their classic clinical context especially because of their peculiar histologic findings. Moreover, it may be hypothesized that variation in morphology might be related to different evolutive stages of the cell of origin. To support this hypothesis, we therefore studied the presence of components of the Notch pathway inside and outside the lesion. Their absence inside the tumor and, in contrast, the expression of Notch2 and HES1 evident in overrepresented bile ducts present at the periphery might explain not only the lack of bile ducts, but also indicate a more adult phenotype compared with classic pediatric MHL, which show more bile ducts and liver trabeculae embedded in the mesenchymal matrix.

Liver transplantation for a giant mesenchymal hamartoma of the liver in an adult: Case report and review of the literature

Mesenchymal hamartomas of the liver (MHLs) in adults are rare and potentially premalignant lesions, which present as solid/cystic neoplasms. We report a rare case of orthotopic liver transplantation in a patient with a giant MHL. In 2013, a 34-year-old female sought medical advice after a 2-year history of progressive abdominal distention and respiratory distress. Physical examination revealed an extensive mass in the abdomen. Computed tomography (CT) of her abdomen revealed multiple liver cysts, with the diameter of largest cyst being 16 cm × 14 cm. The liver hilar structures were not clearly displayed. The adjacent organs were compressed and displaced. Initial laboratory tests, including biochemical investigations and coagulation profile, were unremarkable. Tumor markers, including levels of AFP, CEA and CA19-9, were within the normal ranges. The patient underwent orthotopic liver transplantation in November 2013, the liver being procured from a 40-year-old man after cardiac death following traumatic brain injury. Warm ischemic time was 7.5 min and cold ischemic time was 3 h. The recipient underwent classical orthotopic liver transplantation. The recipient operative procedure took 8.5 h, the anhepatic phase lasting for 1 h without the use of venovenous bypass. The immunosuppressive regimen included intraoperative induction with basiliximab and high-dose methylprednisolone, and postoperative maintenance with tacrolimus, mycophenolate mofetil, and prednisone. The recipient's diseased liver weighed 21 kg (dry weight) and measured 41 cm × 32 cm × 31 cm. Histopathological examination confirmed the diagnosis of an MHL. The patient did not experience any acute rejection episode or other complication. All the laboratory tests returned to normal within one month after surgery. Three months after transplantation, the immunosuppressive therapy was reduced to tacrolimus monotherapy, and the T-tube was removed after cholangiography showed no abnormalities. Twelve months after transplantation, the patient remains well and is fulfilling all normal activities. Adult giant MHL is extremely rare. Symptoms, physical signs, laboratory results, and radiographic imaging are nonspecific and inconclusive. Surgical excision of the lesion is imperative to make a definite diagnosis and as a cure. Liver transplantation should be considered as an option in the treatment of a non-resectable MHL.

Mesenchymal hamartoma or embryonal sarcoma of the liver in childhood: a difficult diagnosis before complete surgical excision

BACKGROUND

Clinical experience shows that the primary diagnosis of mesenchymal hamartoma (MHL) and embryonal sarcoma of the liver (ESL) recurrently is mistaken, leading to inadequate managements. We evaluated the accuracy of the primary diagnosis of those liver tumors, compared with the final histological diagnosis.

METHODS

Records of 25 children (0-16 years, treated 01/1989-01/2013) with final diagnosis of MHL or ESL were analyzed.

RESULTS

Final diagnosis was MHL in 18/25 children (10 solid-cystic, 2 cystic, 6 solid) and ESL in 7/25 (4 solid-cystic, 1 cystic, 2 solid). Only 3/7 ESL patients and 15/18 MHL patients fell into the "typical" age group. In 13/25 children primary diagnosis was based on imaging only. Overall, primary diagnosis was concordant with the final diagnosis in 17/25 patients. Of 99/25 biopsied cases, 4/9 biopsy results exposed the wrong final diagnosis; of cystic-solid masses 4/14 were mistaken, of cystic masses 1/3, of solid masses 3/8.

CONCLUSION

Preoperative diagnosis of MHL and ESL is challenging because of atypical clinical presentation, misleading "typical" radiological findings, and difficult interpretation of biopsies. If feasible, complete surgical resection of, in particular, solid-cystic liver masses in the pediatric age group must be aimed for, to get a definitive, final diagnosis, followed by an adequate treatment strategy.

Undifferentiated embryonal sarcoma of the liver in a middle-aged adult with systemic lupus erythematosus

Adult primary undifferentiated embryonal sarcoma of the liver (UESL) is a rare disease. While the etiology of UESL remains largely unknown, association with systemic inflammatory disorders has been observed. Here, we report a case of UESL in a 46-year-old woman with systemic lupus erythematosus (SLE) and without chronic hepatitis or liver cirrhosis. Systematic review of the publicly available English language medical literature identified only 27 cases of UESL in patients aged >45 years and none with SLE. Our patient presented with abdominal pain and had a 2-year history of SLE. Abdominal ultrasonography and enhanced computed tomography revealed a solid mass in the right lobe of the liver. Presumptive diagnosis of atypical hepatocellular carcinoma was made and the patient was treated with segmentectomy of S5 and S4a and cholecystectomy. The final diagnosis of UESL was made according to the pathology results. Since SLE patients may be at increased risk of malignancy, it is possible that the SLE pathogenesis may have contributed to the development of UESL in our patient. According to this case, UESL should be considered when SLE patients present with hepatic space-occupying lesions.

Undifferentiated embryonal sarcoma of the liver with focal osteoid picture-a case report

Undifferentiated embryonal sarcoma of the liver (UESL) is a rare primary liver tumor. Less than 100 adult cases were reported. It has female and right lobe preponderance. In pathological features, focal osteoid picture in UESL is never reported. We present a 63-year-old male patient with left lobe UESL with focal osteoid picture. He was admitted for a palpable solid mass, with left upper quadrant abdominal pain for 4 months. Abdominal computed tomography showed a huge well-circumscribed mass at left upper quadrant, 21.3 × 13 × 27.9 cm(3) in size, with multiple septa in delayed phase. En bloc resection including lateral segmentectomy, splenectomy, and cholecystectomy were performed, but tumor rupture was noted. The pathologic diagnosis was ruptured UESL. The postoperative course was uneventful, and adjuvant radiotherapy without chemotherapy was performed. Peritoneal seeding with massive ascites was noted in the 9(th) month after operation. Even after receiving salvage chemotherapy, he died 1 year after operation. Early complete surgical resection with adjuvant chemotherapy may improve prognosis of UESL. But the overall survival of UESL did not improve until recently. We present this case along with a literature review of the clinical pictures, diagnosis, pathology presentation, pathologicogenesis of focal osteoid picture, treatment, and prognosis for UESL of another 23 new reported cases since 2007.