New sonographic appearance of hepatic mesenchymal hamartoma in childhood

3D simulation assisted resection of giant hepatic mesenchymal hamartoma in children

OBJECTIVE

To evaluate the usefulness of Hisense Computer Assisted Surgery System (Hisense CAS) in pre-operative surgical planning and intra-operative navigation for resection of pediatric giant hepatic mesenchymal hamartoma (HMH).

METHODS

Five children with HMH underwent hepatectomy in our hospital. Pre-operative abdominal enhanced CT was performed for diagnosis and treatment planning. Using CT DICOM files, three-dimensional reconstruction was performed in three cases for operation planning and intra-operative navigation, with SID carrying out precise liver resection during the operation with Hisense CAS.

RESULT

Two patients underwent right and left lobe hepatectomy, respectively, based only on enhanced CT. In 3 patients, by using the Hisense CAS system, three-dimensional reconstruction of the liver and tumors was successfully completed, and virtual hepatectomy performed successfully according to surgical plans. Hisense CAS could clearly and directly indicate the HMH location and shape, as well as its relationship with the intra-hepatic Glisson system, assisting safe hepatectomy. All five patients recovered well from surgery without any complications, and pathological examinations confirmed that all cases were HMH. No recurrence was observed during the follow-up period of 3 months to 5 years.

CONCLUSION

Hisense CAS system is useful for preoperative planning and intra-operative navigation, assisting safer hepatectomy.

Cystic hepatic mesenchymal hamartoma: the role of radiology in diagnosis and perioperative management

A 13-month-old male presented with large hepatic mass that was confirmed diagnostically to be a cystic hepatic mesenchymal hamartoma. The sieve-like appearance of the solid components of the mass, as seen at ultrasonography, and findings of dynamic post-contrast MRI are highlighted here. Beyond diagnostic imaging, we extended our role in patient management through ultrasound-guided intra-operative aspiration of fluid from the cystic components of the tumour to reduce its volume and thereby facilitate surgical resection.

Long-term follow up of mesenchymal hamartoma of liver--single center study

BACKGROUND/AIM

Mesenchymal hamartoma of liver (MHL) is a rare liver tumor of childhood. About 200 cases have been reported till now. Most of the work on MHL is limited to case reports and there are not many long term follow-up studies. We present our 20 years of experience with this uncommon entity. This study aims to highlight clinical features, diagnosis and treatment of MHL.

MATERIALS AND METHODS

All patients with a diagnosis of MHL in last 20 years were included in this retrospective study. The patients were evaluated clinically, radiologically and pathologically.

RESULTS

The total number of patients with a diagnosis of MHL was nine. Mean age of the patients was 19.89 ± 2.75 months. Right lobe was involved in eight patients. The prominent clinical features were distension of abdomen and anorexia. Surgical options used were hepatic lobectomy, wedge resection and enucleation. Histopathology of the specimens showed cysts of variable size with normal hepatocytes, bile ducts and connective tissue stroma. Overall mortality was one (11.11%).

CONCLUSION

MHL is a benign tumor that can present with various clinical features. It should be differentiated carefully from other liver masses especially malignant ones. The diagnosis can be made with the help of radiology and histopathology. Adequate resection is curative in most of the cases and long-term follow up is satisfactory.

From the archives of the AFIP: Pediatric liver masses: radiologic-pathologic correlation part 1. Benign tumors

Benign hepatic tumors in children include lesions that are unique to the pediatric age group and others that are more common in adults. Infantile hemangioendothelioma, or infantile hepatic hemangioma, is a benign vascular tumor that may cause serious clinical complications. It is composed of vascular channels lined by endothelial cells. At imaging, large feeding arteries and draining veins and early, intense, peripheral nodular enhancement with centripetal filling on delayed images are characteristic features. Mesenchymal hamartoma of the liver occurs in young children and is characterized pathologically by mesenchymal proliferation with fluid-containing cysts of varying size and number. The mesenchymal component or cystic component may predominate; this predominance determines the imaging appearance of the tumor. Benign epithelial tumors that are common in adults may infrequently occur in childhood. These include focal nodular hyperplasia (FNH), hepatocellular adenoma, and nodular regenerative hyperplasia. All are composed of hyperplastic hepatocytes similar to surrounding liver parenchyma and may be difficult to discern at imaging. Preferential hepatic arterial phase enhancement helps distinguish FNH and hepatic adenoma from uninvolved liver. Hepatic adenoma often has intracellular fat and a propensity for intratumoral hemorrhage, neither of which are seen in FNH. Unlike adenoma, FNH often contains enough Kupffer cells to show uptake at sulfur colloid scintigraphy. Nodular regenerative hyperplasia is often associated with portal hypertension, which may be evident at imaging. Knowledge of how the pathologic features of these tumors affect their imaging appearances helps radiologists offer an appropriate differential diagnosis and management plan.

[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.

Mesenchymal hamartoma of the liver

Mesenchymal hamartoma of the liver is the second most common benign liver tumor of childhood. Ultrasonography demonstrates a cystic lesion that may be very large. Computed tomographic scan will further establish the location and its relationship to vascular anatomy. Most will be amenable to gross total resection with clear margins. To illustrate the radiological and gross operative features, we present a 9-month-old male infant with a mesenchymal hamartoma with classic features.

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.

Mesenchymal hamartoma of the liver: a systematic review

Mesenchymal hamartoma of the liver is the second commonest benign liver tumor in children, yet its biology and pathogenesis are poorly understood. Cytogenetic studies have suggested that the tumor may be a neoplasm rather than a hamartoma. Typically, it presents as a large benign multicystic liver mass in a child younger than 3 years amenable to complete resection. However, its imaging characteristics are variable, ranging from a few large cysts to a solid mass occupying one or both lobes of the liver. In addition, the tumor occasionally contains angiomatous elements or is multifocal. Most tumors gradually increase in size, some reaching enormous proportions, which can make surgery challenging. Paradoxically, a few undergo incomplete spontaneous regression and, on rare occasions, others have shown malignant transformation to undifferentiated (embryonal) sarcoma. These unusual pathological and biological features must be taken into account when considering the management of affected individuals.

Hepatic mesenchymal hamartoma

Hepatic mesenchymal hamartoma (HMH) is a rare liver tumour in childhood. It is believed to be a benign tumour with a good prognosis if the tumour is excised. Only a few cases with local relapse or metastasis have been reported. We reviewed 134 patients with space-occupying liver lesions, from January 1990 to December 1999, and four patients with HMH were found. Abdominal mass and/or distension were the common initial presentations. Three of our four cases were diagnosed in the first year of life. The liver function tests and tumour markers were non-specific. Case 1 underwent tumour enucleation and another three cases underwent tumour excision. One patient died. No tumour recurrence was noted in the surviving patients.

Hepatic tumors in children

Although they account for only 1% to 4% of solid tumors in children, hepatic tumors and pseudotumors offer a diagnostic challenge to the clinician seeing only an occasional case. Metastatic lesions such as neuroblastoma, Wilms' tumor, and lymphoma are the most common neoplasm seen in the liver, but 10 distinct primary tumors and pseudotumors of the liver occur with some regularity, and a few others may be seen rarely, including leiomyosarcoma, rhabdoid tumor, and endodermal sinus tumor. Five of these neoplasms--hepatoblastoma, infantile hemangio-endothelioma, mesenchymal hamartoma, undifferentiated embryonal sarcoma, and embryonal rhabdomyosarcoma of the biliary tree--occur only in children and are the major focus of the article.

Mesenchymal hamartoma of the liver

We present a multiseptated mesenchymal hamartoma of the liver in a 10-year-old male patient, a rare benign tumor of childhood. The characteristic ultrasound and CT appearances of this unusual tumor are reviewed. A single septal calcification associated with this tumor was demonstrated, an association which has not previously been reported. The differential diagnosis for cystic liver lesions is discussed in detail.