Undifferentiated embryonal sarcoma with unusual features arising within mesenchymal hamartoma of the liver: report of a case and review of the literature

Huge mesenchymal hamartoma in a young adult: a case report

Mesenchymal hamartoma of the liver (MHL) is rare. Less than 50 adult cases have been described. Due to their potential degeneration or recurrence, a complete surgical resection must be performed. We describe a case of a 26-year-old with a palpable solid lesion, which displaced abdominal organs. Percutaneous needle biopsies suggested the diagnosis of MHL. A right hemi-hepatectomy without segment 1 was performed; the post-operative course was uneventful. The mesenchymal component of the tumour was reactive to desmin and smooth muscle actin. Low proliferation index was confirmed (MIB1). Genetic counselling: the sequencing analysis of DICER1 and CDKN1C gene was negative, DNA methylation analysis on the chromosome 11p15 region was normal. After 42 months, there was no recurrence. In conclusion, clinicians should consider MHL in the differential diagnosis. The dimension and the need of radicality impose major liver resections or liver transplantations, which should be performed in referral centres.

Treatment of Undifferentiated Embryonal Sarcoma of the Liver in Children

Undifferentiated embryonal sarcoma of the liver is a rare mesenchymal tumor with a highly malignant potential. It occurs almost exclusively in the pediatric population and typically has a poor outcome. Although previous studies have reported dismal prognoses, recent advances in combined treatment modalities, e.g., surgery and chemotherapy, have given cause for optimism. Even in those diseases not amenable to complete surgical resection or refractory diseases, other treatment modalities, such as liver transplant, have yielded promising results. This paper provides a review of the current treatment modalities for hepatic undifferentiated embryonal sarcoma in children.

Outcomes of Primary Tumor Excision do not Differ from Non-Resection Methods in Pediatric Mesenchymal Hamartoma of the Liver: A Rapid Systematic Review

BACKGROUND

To conduct a rapid systematic review comparing the outcomes of primary tumor resection versus non-resection on patients with hepatic mesenchymal hamartoma.

METHODS

We searched the Ovid MEDLINE, EMBASE, Scopus, PubMed, Web of Science, and Google Scholar databases from January 1, 2000 to March 31, 2022. Studies that described cases of hepatic mesenchymal hamartoma, including management and outcomes, were included.

RESULTS

62 articles met inclusion criteria with 95 cases in total. Patients were assigned to the primary tumor resection (n = 85) or non-resection (n = 10) cohort based on the described management. Similar rates of morbidity (17% vs 20%) and mortality (6 vs 10%) were identified between cohorts. There were no differences in sex, liver lobe involvement, or tumor size among study groups.

CONCLUSIONS

Complete tumor resection should remain the gold standard for hepatic mesenchymal hamartomas when an adequate liver remnant exists. Reports of non-resected tumors demonstrating spontaneous regression or stability with watchful waiting have poor long term follow-up and have inadequate evidence of a true mesenchymal hamartoma diagnosis.

LEVEL OF EVIDENCE

Level I.

Case Report of Undifferentiated Hepatic Embryonal Sarcoma with Mesenchymal Hamartoma: A Rare Entity

Undifferentiated embryonal sarcoma (UES) is a highly malignant hepatic neoplasm, which occurs mostly in pediatric population. There is a link between embryonal sarcoma and mesenchymal hamartoma as evidenced by clinicopathological overlap and similar genetic abnormality. Here, we report a case of UES in a young female in a background of mesenchymal hamartoma of liver.

Progression of a persisting mesenchymal hamartoma to intrahepatic cholangiocarcinoma 24 years after the initial diagnosis: A case report

Mesenchymal hamartoma of the liver (MHL) is a rare benign tumor that often presents in early childhood, and it rarely occurs in adulthood. Aberrant development of the portal tract is a known cause of MHL. Although limited information is available on the natural course of MHL, malignant transformation has been reported in a few cases. Here, we report a case of a 26-year-old female with intrahepatic cholangiocarcinoma secondary to unresected MHL. The patient underwent resection of the hepatic mass, which was diagnosed as MHL at 2 years of age, due to an increase in mass size and a suspicion of malignant transformation during work-up. Histopathology confirmed intrahepatic adenosquamous carcinoma in the background of MHL, with a T2N0M0 pathological stage (stage II). The surgical margin was free from tumor cells. The patient fully recovered postoperatively and started receiving adjuvant chemotherapy. Previous case reports have only reported about the development of undifferentiated embryonal sarcoma or angiosarcoma as malignant transformation of MHL. Cases of other malignancies have not been published; however, it is difficult to rule out the occurrence of various malignancies related to the portal tract when considering the pathogenesis of the disease. To the best of our knowledge, this is the first case report of adenocarcinoma of bile duct origin secondary to MHL. This case report suggests that aggressive surgical management should be considered after the initial diagnosis of MHL.

Undifferentiated embryonal sarcoma of the liver: A rare hepatic tumor and its related characteristic radiological features

The undifferentiated embryonal sarcoma of the liver is a rare tumor with a poor prognosis, with improved outcomes being reported with more recently multimodality treatments. We report a case of a 6-year-old girl with an incidentally diagnosed and histologically proven localized undifferentiated embryonal sarcoma of the liver. The divergence between solid appearance at US and cystic-like appearance on CT/MRI, which has been attributed to the presence of myxoid component frequently described with this tumor, was crucial for the diagnosis and subsequent treatment.

Mesenchymal hamartoma and undifferentiated embryonal sarcoma: diagnostic keys that radiologists need to know

OBJECTIVE

Hepatic tumors are uncommon in pediatric patients. Among the most common of these uncommon tumors are mesenchymal hamartoma and undifferentiated embryonal sarcoma, which have different origins but similar appearance on imaging studies. This paper reviews the characteristic findings and differential diagnosis of these entities. Ultrasonography is the first-line imaging test to study these tumors. Magnetic resonance imaging and computed tomography are useful for further characterizing the tumors and planning surgery.

CONCLUSION

Radiologists need to be familiar with the imaging findings of the different disease entities and to evaluate them together with the patient's age, personal history, and bloodwork.

Undifferentiated sarcoma of the liver: Multicenter international experience of the Cooperative Soft-Tissue Sarcoma Group and Polish Paediatric Solid Tumor Group

BACKGROUND

Undifferentiated embryonal sarcomas of the liver (UESL) are extremely rare and continue to pose a diagnostic and therapeutic challenge. The aim of the study was to present a multicenter experience of the German CWS and Polish PPSTG groups in the treatment of UESL in children.

PROCEDURE

Twenty-five patients were treated according to the CWS-96, CWS-2002, and CYVADIC protocols. Distant metastases were observed in four cases (16%). In four cases, an initial disease presentation mimicked other entities. A pure cystic appearance of liver mass led to misdiagnosis of hydatid cyst in three cases. In one case, laparotomy was performed due to the signs of appendicitis, and bleeding from ruptured liver tumor was found. All these patients were finally diagnosed as UESL.

RESULTS

Thirteen patients received preoperative chemotherapy. Partial response was observed in 10 cases. Tumor resection was performed in 20 patients (primary resections, 12; delayed resections-, 8). In five patients, the primary tumor never became operable. The macroscopically complete resection rate was 95% (19/20). Postoperative chemotherapy was given to 20 children. Local radiotherapy was used in three children. After a median follow-up time of 136 months, 17 patients (68%) were alive with no evidence of disease. All children with unresectable tumor and three out of four patients with distant metastases died. The five-year overall survival (OS) rate was 72%.

CONCLUSIONS

In summary, a complete tumor excision plays the central role in the treatment of UESL. A cystic presentation of the liver lesion on imaging does not exclude the diagnosis of malignant tumor.

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.

The genomic landscape of undifferentiated embryonal sarcoma of the liver is typified by C19MC structural rearrangement and overexpression combined with TP53 mutation or loss

Undifferentiated embryonal sarcoma of the liver (UESL) is a rare and aggressive malignancy. Though the molecular underpinnings of this cancer have been largely unexplored, recurrent chromosomal breakpoints affecting a noncoding region on chr19q13, which includes the chromosome 19 microRNA cluster (C19MC), have been reported in several cases. We performed comprehensive molecular profiling on samples from 14 patients diagnosed with UESL. Congruent with prior reports, we identified structural variants in chr19q13 in 10 of 13 evaluable tumors. From whole transcriptome sequencing, we observed striking expressional activity of the entire C19MC region. Concordantly, in 7 of 7 samples undergoing miRNAseq, we observed hyperexpression of the miRNAs within this cluster to levels >100 fold compared to matched normal tissue or a non-C19MC amplified cancer cell line. Concurrent TP53 mutation or copy number loss was identified in all evaluable tumors with evidence of C19MC overexpression. We find that C19MC miRNAs exhibit significant negative correlation to TP53 regulatory miRNAs and K-Ras regulatory miRNAs. Using RNA-seq we identified that pathways relevant to cellular differentiation as well as mRNA translation machinery are transcriptionally enriched in UESL. In summary, utilizing a combination of next-generation sequencing and high-density arrays we identify the combination of C19MC hyperexpression via chromosomal structural event with TP53 mutation or loss as highly recurrent genomic features of UESL.

A case of adult undifferentiated embryonal sarcoma of the liver successfully treated with right trisectionectomy: a case report

Background

Undifferentiated embryonal sarcoma of the liver (UESL) is a rare malignant mesenchymal tumor that usually occurs in children and is rarely diagnosed in adults.

Case presentation

Here, we describe the case of a 65-year-old woman who presented with a huge cystic lesion in the liver. Laboratory studies performed on admission showed modest inflammation, poor nutrition, and elevated levels of total bilirubin, alkaline phosphatase, and γ-glutamyl transferase. Computed tomography showed a well-defined, heterogeneous tumor with multiple cysts involving the right lobe and the medial segment of the liver, with a maximum diameter of 16 cm. Positron emission tomography/computed tomographic scans showed the uptake of 2-(fluorine-18)-fluoro-2-deoxy-d-glucose in a part of the cyst. The patient was diagnosed with mucinous cystadenocarcinoma or sarcoma of the liver and underwent right trisectionectomy. Histopathological studies revealed that the tumor was composed of pleomorphic and polynuclear dyskaryotic cells with eosinophilic globules in the cytoplasm. Mesenchymal hamartoma-like tissue was observed in the peripheral part of the tumor. Immunohistochemical analyses showed the tumor stained with vimentin, α-smooth muscle actin, desmin, α1-antitrypsin, and α1-antichymotripsin. Therefore, a histological diagnosis of UESL was made. Eighteen months following treatment, two recurrent tumors in the remnant liver were detected and resection of the recurrent tumors was performed.

Conclusions

A UESL should be considered in the differential diagnosis of large cystic hepatic lesions. Although the prognosis of UESL is extremely unfavorable, aggressive surgical resection should be the most important factor for ensuring long-term survival.

Imaging features of undifferentiated embryonal sarcoma of the liver: a series of 15 children

BACKGROUND

Undifferentiated embryonal sarcoma of the liver is a rare malignant mesenchymal tumour occurring mostly in children ages 6-10 years. The discrepancy between its solid appearance on US and cystic-like appearance on CT has been described.

OBJECTIVE

To study the imaging particularities and similarities among our cases of undifferentiated embryonal sarcoma and to report the errors in initial diagnoses.

MATERIALS AND METHODS

We conducted a retrospective study of 15 children with undifferentiated embryonal sarcoma diagnosed or referred to our hospital during 1997-2015 and analysed the clinical, biological and imaging data.

RESULTS

We identified eight boys and seven girls ages 9 months to 14 years. Ten children presented with abdominal pain. Alpha-fetoprotein was slightly increased in one. Initial US and CT had been performed for all, while additional MRI had been done in two children. Initial CT demonstrated a hypoattenuated mass in all. Rupture was seen in five and intratumoural bleeding in seven children. Tumour volumes reduced during neoadjuvant chemotherapy in 10 children.

CONCLUSION

Undifferentiated embryonal sarcoma might be suggested in a non-secreting unifocal tumour with well-defined borders, fluid-filled spaces on US, hypoattenuation and serpiginous vessels on CT, and if there are signs of internal bleeding or rupture on CT or MRI.

Pathology of the liver in children: Where would I (we) be without "Pepper"?

A tribute to Pepper's lasting contributions to Hepatopathology.

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.

Undifferentiated Embryonal Sarcoma of the Liver (UESL): A Single-Center Experience and Review of the Literature

Undifferentiated embryonal sarcoma of the liver (UESL) is a rare and aggressive pediatric malignancy. The purpose of this study was to review the clinical, radiologic, and pathologic features and outcome of children with UESL at our institution, in the United Network of Organ Sharing database and to review the existing literature to define the state of the art for children with UESL. Six children were diagnosed with UESL at the Texas Children's Cancer Center between 1993 and 2014, 12 children underwent liver transplantation registered in the United Network of Organ Sharing database, and 198 children with UESL were described in 23 case series during 1978 to 2014. Patients were treated with multimodal treatment approaches including primary surgical resection, neoadjuvant and/or adjuvant chemotherapy, and liver transplantation resulting in overall survival reported between 20% and 100% with significant improvement over the recent years. We show that complete tumor removal remains the key element of treatment and our single-institutional experience and data in the published literature suggest that combination chemotherapy with ifosfamide and doxorubicin to facilitate complete surgical resection is an effective approach to cure children with UESL.

Undifferentiated Embryonal Sarcoma of Liver

Undifferentiated embryonal sarcoma of the liver (UESL) is a rare malignant hepatic tumor. A 47 year old male presented with symptoms of sour taste in his mouth, occasional nausea, indigestion and 15-pound weight loss over two months. He had an unremarkable upper gastrointestinal endoscopy. Imaging showed a large liver mass in the left hepatic lobe that was resected and then reported as UESL. He went on to develop lung metastases and was initially treated with doxorubicin and ifosfamide followed by switching of therapy to gemcitabine and docetaxel due to progression of disease. He had a good response after two cycles and went on to receive four more cycles, achieving stable disease. We can therefore conclude that the combination of gemcitabine and docetaxel is a potential therapeutic option for patients with UESL.

Mesenchymal Hamartoma of the Liver in an Infant With Beckwith-Wiedemann Syndrome: A Rare Condition Mimicking Hepatoblastoma

Patients with Beckwith-Wiedemann syndrome (BWS) are known to be at an increased risk for childhood malignancies, particularly Wilms tumor and hepatoblastoma. We report a case of genetically confirmed BWS in a 5-month-old girl who presented with a 9.5-cm abdominal mass associated with elevated α-fetoprotein levels. The clinical impression was strongly suggestive of hepatoblastoma. Histologic examination of the surgically excised mass revealed mesenchymal hamartoma of the liver (MHL), a benign hepatic neoplasm.

Rare benign tumors of the liver: still rare?

Background

Benign liver tumors are common. They do not spread to other areas of the body, and they usually do not pose a serious health risk. In fact, in most cases, benign liver tumors are not diagnosed because patients are asymptomatic. When they are detected, it’s usually because the person has had medical imaging tests, such as an ultrasound (US), computed tomography (CT) scan, or magnetic resonance imaging (MRI), for another condition.

Materials and methods

A search of the literature was made using cancer literature and the PubMed, Scopus, and Web of Science (WOS) database for the following keywords: “hepatic benign tumors”, “hepatic cystic tumors”, “polycystic liver disease”, “liver macroregenerative nodules”, “hepatic mesenchymal hamartoma”, “hepatic angiomyolipoma”, “biliary cystadenoma”, and “nodular regenerative hyperplasia”.

Discussion and conclusion

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors in some areas of the world; there is an increasing incidence worldwide. Approximately 750,000 new cases are reported per year. More than 75 % of cases occur in the Asia-Pacific region, largely in association with chronic hepatitis B virus (HBV) infection. The incidence of HCC is increasing in the USA and Europe because of the increased incidence of hepatitis C virus (HCV) infection. Unlike the liver HCC, benign tumors are less frequent. However, they represent a chapter always more interesting of liver disease. In fact, a careful differential diagnosis with the forms of malignant tumor is often required in such a way so as to direct the patient to the correct therapy. In conclusion, many of these tumors present with typical features in various imaging studies. On occasions, biopsies are required, and/or surgical removal is needed. In the majority of cases of benign hepatic tumors, no treatment is indicated. The main indication for treatment is the presence of significant clinical symptoms or suspicion of malignancy or fear of malignant transformation.

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 liver sarcoma in childhood: A case report

In order to improve the diagnosis and therapy of undifferentiated embryonal liver sarcoma (UELS), the present study presents the case of a 9-year-old female with UELS and discusses UELS in childhood. The patient presented with abdominal pain and fever. The laboratory tests, radiographic examination and pathological features presented by the female were similar to those of typical cases of UELS reported in childhood. The patient initially received surgical treatment and the immunohistochemical findings suggested that the patient had UELS. The patient’s parents refused adjuvant chemotherapy and demonstrated a right prerenal mass 6 months post-surgery. Microscopic examination revealed that the tumor was evidence of undifferentiated embryonal sarcoma recurrence. However, the patient was comfortable and physical examination revealed no abnormal conditions. In addition, the laboratory results were normal. Abdominal computed tomography scan and ultrasound were performed every 3 months to monitor the tumor recurrence. At the time of writing, it has been 6 months after the second surgical procedure and there has been no appearence of abnormalities. Previous studies have shown that patients who receive combined therapy with complete tumor resection and adjuvant chemotherapy have a longer survival time than those who undergo surgical therapy alone. Complete tumor resection combined with adjuvant chemotherapy may reduce the risk of recurrence and enhance the survival time in patients with UELS.

Chondroid hamartoma of the liver

A 60-year-old patient presented with a solitary mass within the right hepatic lobe. Diagnostic imaging revealed a solid tumor on the diameter of 3 cm. In absence of any extrahepatic manifestation and based on FNAC findings the lesion was classisfied a primary hepatic chondroid sarcoma. However, after right hemihepatectomy histologic assessment resulted the final diagnosis of a benign chondroid hamartoma. Our findings add another variant to the versatile phenotype of liver hamartoma.

Treatment of undifferentiated embryonal sarcoma of the liver in children--single center experience

BACKGROUND

Undifferentiated embryonal sarcoma of the liver (UESL) represents less than 5% of all malignant hepatic tumors in childhood. It is considered an aggressive neoplasm with an unfavorable prognosis. The aim of this paper is to present a single center experience in the treatment of children with UESL.

MATERIALS AND METHODS

Ten children with UESL were treated between 1981 and 2012. Age at diagnosis ranged from 4 months to 17 years (median age, 6 years and 9 months). Surgery after neoadjuvant chemotherapy (CHT) was performed in 7 patients, and in 3 patients primary surgery was done. Adjuvant chemotherapy was administered in all 10 patients (CYVADIC, CAV, CAV/ETIF/IF+ADM, CDDP/PLADO). Right hemihepatectomy was performed in 1 patient, extended right hemihepatectomy in 6, and partial resection of the right lobe (segments V-VI, segment V) in 2 patients. One patient with unresectable tumor affecting both lobes was listed for liver transplantation (LTx).

RESULTS

Follow-up from diagnosis ranged from 50 to 222 months (mean 138 months). Among 9 patients treated with partial liver resection, distant metastases/local recurrence was not observed in any, and disease-free survival in this group is 100% (9 patients alive). The patient that underwent liver transplantation died of multiorgan failure 4 months postoperatively. However, this patient was misdiagnosed as having hepatoblastoma (HBL) and received PLADO chemotherapy. The overall survival rate is 90%.

CONCLUSION

Excellent results with long-term survival can be achieved in children with UESL with conventional therapy, including a combination of neoadjuvant and adjuvant chemotherapy and surgery, even in large extensively growing tumors.

Characterization of translocations in mesenchymal hamartoma and undifferentiated embryonal sarcoma of the liver

BACKGROUND

Mesenchymal hamartoma of the liver (MHL) is an uncommon benign primary liver tumor that typically occurs in the pediatric population, although cases have been described in adults. MHL is sometimes associated with the highly malignant undifferentiated embryonal sarcoma (UES), and the synchronous or metachronous occurrence of MHL and UES suggests they share a common genetic link. Although the exact mechanism of tumorigenesis has not been identified, MHL cases harbor recurring chromosomal rearrangements involving 19q13.

DESIGN

In order to provide more details on the genetic events of MHL tumorigenesis, capture-based next generation sequencing (NGS) targeted to loci recently shown to be involved in a translocation in a case of UES arising in MHL (specifically, the MALAT1 gene on chromosome 11 and a gene poor region termed MHLB1 on chromosome 19) was performed on formalin fixed paraffin embedded tissue from seven cases of MHL.

RESULTS

Chromosome rearrangements involving the MHLB1 locus were identified in three of the seven cases, including the translocation t(11,19)(q13.1;q13.42) involving the MALAT1 gene; the translocation t(2,19)(q31.1;q13.42) involving AK023515, an uncharacterized noncoding gene; and the inversion inv(19,19)(q13.42;q13.43) involving the PEG3 gene encoding a Kruppel-type zinc-finger protein. Rearrangements were exclusively identified in pediatric tumors. In each case, the presence of the rearrangement was confirmed by PCR and interphase FISH. Interphase FISH also demonstrated that the arrangements occur within the spindle cell component but not within the epithelial components of the tumor.

CONCLUSIONS

Since the MHLB1 locus contains a CpG-rich region whose methylation regulates C19MC miRNA genes, rearrangements that disrupt this region may contribute to MHL development through alteration of miRNA expression. The demonstration that the loose stromal cells harbor the rearrangements indicates that (some cases of) MHL are a neoplastic process due to a somatic genetic change and not a germline abnormality.

Current concepts in pediatric liver tumors

Liver tumors in children can be classified into benign or malignant; some of the benign lesions can have the potential of malignant transformation, and therefore the therapeutic approach may change. These neoplasms account for nearly 1-2% of all pediatric tumors and they have gained significant attention in the last decades due to data suggesting that the incidence may be increasing 5% annually. We know that with new and improved imaging modalities some of these lesions may be detected more often than before. Recent studies showed that liver cancer represented 2% of malignancies in infants by 1980s and this was doubled in incidence to 4% in the following 10 yr. In this review our aim is to discuss all primary liver tumors in children with attention to their clinicopathological and immunohistochemical features followed by the current standard of care.

Renal and hepatic tumors in the neonatal period

Renal and hepatic tumors in neonates are extremely rare. Nevertheless it is important for clinicians to be familiar with them. Both renal and hepatic neonatal tumors are heterogeneous collections of several tumor types. Some renal and hepatic tumors are benign and may require no interventions whereas others can be associated with significant morbidity and even mortality and may require multimodality treatment. Early diagnosis and initiation of the proper treatment plan is crucial for achieving the best outcomes for these rare tumors in this vulnerable population.

Molecular cytogenetic characterization of undifferentiated embryonal sarcoma of the liver: a case report and literature review

Undifferentiated embryonal sarcoma of the liver (UESL) represents a heterogeneous group of tumors derived from mesenchymal tissues. Earlier cytogenetic studies in limited cases demonstrated that UESL is associated with a recurrent translocation t(11;19)(q11;q13.3-q13.4) or add(19)(q13.4). In this report, we present our array comparative genomic hybridization (aCGH), fluorescence in situ hybridization (FISH) findings, and a missense mutation of TP53 gene by DNA sequencing in a 19-year-old patient with UESL. The data were compared to laboratory findings reported by previous studies.

[Paediatric malignant liver tumours]

Tumours and pseudotumours of the liver are a heterogeneous group of neoplasm including 60% of malignant tumours. Malignant liver tumours account for less than 2% of the lesions in children and vary considerably in incidence throughout the paediatric age range, with hepatoblastoma, rhabdoid tumour of the liver, hemangioendothelioma, biliary tract rhabdomysosarcoma and mesenchymal hamartoma in the first two years of life and hepatocellular carcinoma, focal nodular hyperplasia, and undifferentiated sarcoma in older children and adolescents. Treatment of malignant epithelial tumours is based on the surgical resection of the tumour associated with pre- and postoperative chemotherapy including cisplatinum. Modalities of the treatment are adapted to risk factors. Survival rates at three years are over 80% for localised hepatoblastoma whereas they are less than 30% in hepatocellular carcinomas. The role of targeted therapies still has to be defined.

Eosinophilic and neutrophilic leukemoid reaction in a woman with spindle cell sarcoma: a case report

INTRODUCTION

We report a case of a patient with marked eosinophilia and neutrophilia as a manifestation of a spindle cell sarcoma.

CASE PRESENTATION

A 41-year-old African American woman presented with an enlarging, painful mass in her right knee area. Four years previously, she had had a mass similar to this diagnosed as an osteosarcoma, and had undergone a radical resection and hinge-knee replacement. Before the surgery, she was treated with neoadjuvant docetaxel and gemcitabine. A biopsy was taken from the recurrent mass, and histological examination revealed high-grade soft-tissue sarcoma. The patient received no further treatment. Complete blood counts revealed a white blood cell (WBC) count of 13.6 to 17.9 × 109/L, with neutrophils being 8.2 to 10.9 × 109/L and eosinophils 1.8 to 1.9 × 109/L. At readmission six months later, WBC was 126.7 × 109/L, with neutrophils being 57.02 × 109/L and eosinophils 60.82 × 109/L. The eosinophils peaked at 77.79 × 109/L two days later. Evaluations for allergies, infection, and autoimmune mechanisms were negative. Bone marrow revealed increased eosinophils without blasts. After resection, blood counts abruptly decreased to the normal range. Pathology confirmed high-grade spindle cell sarcoma. Approximately one year after resection, the patient was readmitted with metastatic disease to her lungs. During this presentation, her eosinophil and neutrophil count was again increased. WBC was 107.8 × 109/L, with eosinophil count of 47.43 × 109/L and neutrophil count of 44.10 × 109/L. Interleukin-5 was normal, and granulocyte-macrophage colony-stimulating factor (GM-CSF) was elevated at 208.8 (normal < 4.8).

CONCLUSION

In our case, the patient had eosinophilia and neutrophilia associated with a spindle cell sarcoma, possibly representing a paraneoplastic syndrome secondary to GM-CSF. There were no signs of infectious, allergic, or autoimmune causes for the eosinophilia or neutrophilia. Even though the occurrence of eosinophilia and neutrophilia with malignancy is rare, patients who have either condition without an apparent cause should be checked for malignancy.

Undifferentiated liver embryonal sarcoma in adults: A report of four cases and literature review

AIM: To evaluate the undifferentiated embryonal sarcoma of liver (UESL) in adults in order to improve its diagnosis and treatment.

METHODS: Four primary and one recurrent cases of UESL were clinicopathologically evaluated and immunohistochemically investigated with a panel of antibodies using the EnVision+ system. Relevant literature about UESL in adults was reviewed.

RESULTS: Three males and one female were enrolled in this study. Their chief complaints were abdominal pain, weight loss, or fever. Laboratory tests, imaging and pathological features of UESL in adults were similar to those in children. Immunohistochemistry showed evidence of widely divergent differentiation into mesenchymal and epithelial phenotypes. The survival time of patients who underwent complete tumor resection followed by adjuvant transcatheter arterial chemoembolization (TACE) was significantly longer than that of those who underwent surgical treatment alone.

CONCLUSION: UESL in adults may undergo pluripotential differentiation and its diagnosis should be made based on its morphological and immunohistochemical features. Complete tumor resection after adjuvant TACE may improve the survival time of such patients.

Hepatic transplantation in a child with giant multicystic tumor: pathological and imaging findings

A 30-month-old male white child presented with 13 months of increasing abdominal girth. The MRI and MDCT showed a giant heterogeneous and predominantly cystic mass with thick and nodular septation, measuring approximately 18 x 15 x 20 cm, which occupied almost the whole liver. A histological diagnosis was not possible, which necessitated transplantation. One yr after transplantation the course has been satisfactory without recurrence and with normal hepatic function and negative tumor markers.

Adult Mesenchymal Hamartoma of the Liver: Case Report and Literature Review

Mesenchymal hamartoma of the liver (MHL) is a rare benign lesion occurring primarily in the pediatric population. While the precise pathogenesis of the tumor is not certain, the most common theory relates to aberrant mesenchyme development in the portal tract likely related to the bile ducts. A 53-year-old female was evaluated for an incidental liver mass. Initial CT scan showed a cystic lesion in the right lobe of the liver and follow-up imaging revealed an increase in size and the percent solid component within the mass. In view of these changes, a nondiagnostic biopsy was obtained followed by extirpation of the lesion. Gross pathological review of the lesion identified a 9 × 9 × 7.5 cm, pink-yellow-tan, gelatinous mass, with a >1 cm clear surgical margin. Histologically, the mass consisted of benign dilated bile ducts, as well as myxoid stroma with spindle cells showing smooth muscle differentiation. The patient was discharged home on postoperative day five. A review of the literature for MHL in adults reports 30 previous cases, predominantly published as individual case reports describing the size, lobe(s) of the liver affected, and the cystic/solid nature of the tumor. MHL in adults may represent a potentially premalignant lesion, as the emerging literature supports a potential relationship between MHL and malignant undifferentiated embryonal sarcoma in regards to cytogenetic analysis. Aggressive surgical management of MHL in adults is mandated when feasible.

[Mesenchymal hamartoma of the liver in a child: a case report]

Mesenchymal hamartoma of the liver is a rare, benign tumor that presents mostly before the age of 2 years. Its pathogenesis is poorly understood. We present the case of a 2.5-year-old female patient who had a large cystic mass of the liver of which the hamartomatous nature was confirmed by the pathological examination of the surgical specimen. We discuss the clinicopathological, imaging, and histological features of this unusual tumor through a review of the literature.

Undifferentiated embryonal sarcoma of liver in an old female: Case report and review of the literature

The clinical characteristics of undifferentiated (embryonal) sarcoma of the liver (UESL) were investigated and the best treatment modalities were recommended. Both histology and immuno-histochemistry demonstrated the cellular features of this peculiar tumor. The tumor size was 12 cm × 9 cm × 8 cm in the right liver lobe. The patient underwent surgical resection of the tumor. The postoperative recovery was uneventful and she died eight months after diagnosis. The tumor showed mixed spindle and polygonal cells within the myxoid matrix. Some tumor cells contained eosinophilic hyaline globules that were positive for resistant diastase. Immunohistochemistry showed positive vimentin. Stellate and spindle cells were positively stained with alpha-1-antichymotrypsin (AACT) and CD68. This case indicates that UESL is not obviously differentiated in old-aged adults.

Giant mesenchymal hamartoma of the liver in an adult

We report a case of hepatic mesenchymal hamartoma in an adult; this condition is extremely rare, with only 15 cases having been reported in the English-language literature worldwide. The patient was a 36-year-old woman who was seen at her local hospital for upper abdominal distension. A giant multilocular cystic tumor, which had almost entirely replaced the normal parenchyma of the right lobe of the liver, was diagnosed. She was referred to our hospital, where, with a diagnosis of biliary cystadenoma, the tumor was successfully removed by right hemihepatectomy. After an uneventful postoperative course, the patient was discharged from our hospital. On histological examination, the tumor consisted of numerous cystic lesions without epithelial lining cells; hepatocytes, bile duct, and vascular components, without either lobular structure or atypia, were observed in the pseudocyst wall, leading to a diagnosis of hepatic mesenchymal hamartoma. There have been a few previously reported cases of multifocal hepatic mesenchymal hamartoma reappearing in the remaining liver after hepatectomy, although these cases are considered to be extremely rare. Therefore, periodic follow-up will be necessary for the patient.

Difficulties in the management of mesenchymal hamartomas

AIM

Mesenchymal hamartoma of the liver is an entity with a varied presentation and frequent initial delay in diagnosis. The macroscopic appearance too is quite heterogeneous with solid, cystic and mixed variants being present with varying degrees of vascularity. Management will depend on presentation and expertise available. We look at a single centre experience with the mesenchymal hamartomas.

METHOD

Retrospective patient record review of the past 30 years, 1976-2006.

RESULTS

Seventeen patients aged 1 day to 15 years were identified, with a histopathological diagnosis of mesenchymal hamartoma of the liver. The anatomical location in the liver was 12 in the right liver and the 5 in the left. All patients presented with abdominal distension, eight had significant anorexia and or vomiting. Ultrasound scan was done in all patients. Findings were that of a mass and or cysts. The cysts were multiple in all cases but one and were interspersed with solid elements. Calcification was noted in only two of the patients. Operative approaches were six right hepatectomy, four wedge excision, seven tumour excisions by division of its pedicle; two of these were done laparoscopically, by cyst drainage and excision of the solid component. The tumours were all confirmed as mesenchymal hamartomas; size ranged from 412 to 2,230 g. Complications included three related to misdiagnosis (hydatid disease, and hepatoblastoma). Intraoperative problems consisted of preoperative bleeding resulting in an on-table hypovolaemic arrest and in a second case a bile duct injury. Postoperative problems consisted of an initial incomplete resection, with residual tumour on the IVC. There was rapid regrowth of tumour and death after a second exploration. Two children developed fluid collections requiring re-exploration and drainage. The surviving children have been followed up for a median time period of 4 months (range 1 month-11 years) and are well.

CONCLUSION

Although hamartomas of the liver are histologically benign, their clinical course and the complications of surgical treatment can be significant. They can often pose diagnostic dilemmas and may have a propensity for local recurrence and malignant degeneration.

Stromal-predominant mesenchymal hamartoma of the liver with elevated serum alpha-fetoprotein level

Mesenchymal hamartoma of the liver (MHL) is an uncommon, benign, tumor-like lesion and is usually diagnosed in the first 2 years of life. Its pathogenesis remains unclear. Treatment of choice is radical excision. The authors report a case of solid stromal predominant MHL in a 12-month-old male infant who also had an elevated serum alpha-fetoprotein level. He also had hypospadias, which might represent a spectrum of developmental anomalies. It usually presents as an asymptomatic mass, however, as in the reported case, it may cause several complications due to the compression of surrounding structures. He was successfully treated with total excision of the pedunculated large tumor without any complication.

Pediatric liver tumors--a pictorial review

Hepatic masses constitute about 5-6% of all intra-abdominal masses in children. The majority of liver tumors in children are malignant; these malignant liver tumors constitute the third most common intra-abdominal malignancy in the pediatric age group after Wilms' tumor and neuroblastoma. Only about one third of the liver tumors are benign. A differential diagnosis of liver tumors in children can be obtained based on the age of the child, clinical information (in particular AFP) and imaging characteristics. The purpose of this review is to report typical clinical and imaging characteristics of benign and malignant primary liver tumors in children.

DNA sequence of the translocation breakpoints in undifferentiated embryonal sarcoma arising in mesenchymal hamartoma of the liver harboring the t(11;19)(q11;q13.4) translocation

Undifferentiated embryonal sarcoma of the liver is a highly malignant and aggressive tumor that occasionally arises within mesenchymal hamartoma of the liver (MHL), a benign tumor that typically occurs in young children. Undifferentiated embryonal sarcoma arising in MHL, as well as uncomplicated MHL, frequently harbor rearrangements of band 19q13.4, including the translocation t(11;19)(q13;q13.4). In this study we report the cloning and DNA sequence analysis of the translocation breakpoints in an undifferentiated embryonal sarcoma arising in MHL known to harbor t(11;19). In this case, the breakpoint at 11q13 occurred in the MALAT1 gene, also known as ALPHA. MALAT1 is rearranged in renal tumors harboring the t(6;11)(p21;q13) translocation, and noncoding MALAT1 transcripts are overexpressed in a number of human carcinomas. The breakpoint at 19q13.4 occurs at a locus we refer to as MHLB1, for Mesenchymal Hamartoma of the Liver Breakpoint 1. Although the MHLB1 locus does not contain a known gene, several human ESTs map to the region (a subset of which show homology to the nuclear RNA export factor (NXF) gene family), and the region is conserved between many mammalian species.

Primary and recurrent embryonal sarcoma of the liver: clinicopathological and immunohistochemical analysis

AIMS

To evaluate primary and recurrent embryonal sarcoma of the liver and to improve recognition of its morphological variants and immunohistochemical features.

METHODS AND RESULTS

Fourteen primary and two recurrent cases of hepatic embryonal sarcoma were evaluated histologically and investigated immunohistochemically with a panel of antibodies using the EnVision+ system. They were usually single, large, globular masses with solid and cystic gelatinous areas. Microscopic features included spindle, oval, stellate, epithelioid or multinucleated cells loosely or densely arranged in a myxomatous matrix. Entrapped bile ducts and hepatic cords were often present at the periphery of the tumours. Intracellular and extracellular periodic acid-Schiff-positive, diastase-resistant hyaline globules were commonly present. Recurrent tumours showed greater cellularity, anaplasia and pluripotential differentiation compared with the primary tumour. Immunohistochemistry showed evidence of widely divergent differentiation into mesenchymal and epithelial phenotypes.

CONCLUSIONS

Embryonal sarcoma of the liver may undergo pluripotential differentiation and diagnosis should be based mainly on morphological features. Immunohistochemistry has no specific or diagnostic relevance, but, by using a panel of antibodies, may help to exclude other tumours.