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

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.

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.

Pediatric Mesenchymal Hamartoma of Liver: A Case Report with Histomorphological Differential Diagnosis and Review of Literature

Mesenchymal hamartoma of liver (MHL) is a benign liver tumour that occurs mainly in children, especially those under 2 years old. The pathogenesis of this tumor is still unknown. It is believed that MHL is derived from the Ito cells and either a developmental malformation of primitive hepatic mesenchyme; result of toxic or ischemic insult; or a true neoplasm. It is amenable to treatment and has a good prognosis but presents with varied clinical, imaging and histological findings. However, it can be confused with other hepatic tumors and can mimic malignancy. Therefore, it is important to recognize this rare entity to avoid unnecessary over management. We present a case of MHL in a 3-year-old boy with abdominal distension. Based on the clinical presentation, laboratory and radiological findings a diagnosis of complex cyst of liver was made. A final diagnosis of MHL was given after histopathological examination.

Fine needle aspiration cytology of mesenchymal hamartoma of liver mimicking hepatoblastoma: A case report

Fine-needle aspiration cytology (FNAC) is an effective tool for early and quick diagnosis of malignant and metastatic liver masses. However, diagnosing a benign liver tumor on cytology is a challenging task as they are rarely assessed on cytology and also due to the limitations of the procedure. Mesenchymal hamartoma is an uncommon benign pediatric liver tumor and difficult to diagnose on cytology. We describe here a case of a child who presented with a huge liver mass and clinical suspicion of hepatoblastoma. The child underwent blind FNA, and was diagnosed as mesenchymal hamartoma based on the cytological features. A biopsy was performed subsequently which confirmed the same and then he underwent surgical resection of the tumor. The patient had an uneventful recovery and is disease free on follow up.

Mesenchymal Hamartoma of the Liver: Complete Excision Always Necessary

Mesenchymal hamartoma (MH) is not an uncommon tumor of the liver in the age group of 2-10 years. It is the second most common benign liver tumor in children. Previously considered a developmental anomaly, newer insights into other theories of origin including toxic-metabolic, ischemic, and a true neoplastic process are in progress. Previous understanding of a purely benign nature of the tumor is being overridden by a real malignant transformation. Complete excision of the tumor with clear margins is recommended to achieve a long term cure. A thorough understanding of the natural history of these tumors and skillful surgical treatment are indispensable elements of care.

Benign liver tumors in pediatric patients - Review with emphasis on imaging features

Benign hepatic tumors are commonly observed in adults, but rarely reported in children. The reasons for this remain speculative and the exact data concerning the incidence of these lesions are lacking. Benign hepatic tumors represent a diverse group of epithelial and mesenchymal tumors. In pediatric patients, most benign focal liver lesions are inborn and may grow like the rest of the body. Knowledge of pediatric liver diseases and their imaging appearances is essential in order to make an appropriate differential diagnosis. Selection of the appropriate imaging test is challenging, since it depends on a number of age-related factors. This paper will discuss the most frequently encountered benign liver tumors in children (infantile hepatic hemangioendothelioma, mesenchymal hamartoma, focal nodular hyperplasia, nodular regenerative hyperplasia, and hepatocellular adenoma), as well as a comparison to the current knowledge regarding such tumors in adult patients. The current emphasis is on imaging features, which are helpful not only for the initial diagnosis, but also for pre- and post-treatment evaluation and follow-up. In addition, future perspectives of contrast-enhanced ultrasound (CEUS) in pediatric patients are highlighted, with descriptions of enhancement patterns for each lesion being discussed. The role of advanced imaging tests such as CEUS and magnetic resonance imaging, which allow for non-invasive assessment of liver tumors, is of utmost importance in pediatric patients, especially when repeated imaging tests are needed and radiation exposure should be avoided.

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.

Benign Hepatic Mesenchymal Hamartoma (HMH) - A Case Report

A one-year-old male child presented with progressive enlargement of abdomen and loss of appetite which he had suffered from, since 4 months. Physical examination showed a palpable mass in right hypochondrium. Ultrasonography and MRI showed a solid mass arising from right lobe of liver. The resected mass was well encapsulated, yellowish white in colour and it measured 20 x 18 x 17cm. Cut surface showed a Nutmeg like appearance. Histology showed a well-defined, fibrous capsule with numerous ducts which were lined by flat to low cuboidal epithelium and which were surrounded by concentric layers of fibrous tissue which showed myxoid changes at places. Intervening area showed normal appearing hepatocytes with clear cell changes, dilated congested sinusoids, along with extramedullary haematopoiesis. Based on distinctive morphological features, a histological diagnosis of Benign Hepatic Mesenchymal Hamartoma of liver was made. IHC was not done, as no specific marker has been described for making a differential diagnosis. Benign Hepatic Mesenchymal Hamrtoma (HMH) of liver is an extremely rare tumour of childhood and therefore, the case was considered worth documentation.