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

Liver Transplant for Adult Recurrent Hepatic Mesenchymal Hamartoma and a Feasible Treatment Modality: A Case Report and Literature Review

BACKGROUND

Adult hepatic mesenchymal hamartoma (HMH) is an extremely rare hepatic tumor. Recurrence following complete resection is uncommon. Liver transplantation (LT) is described as a possible treatment option in nonresectable HMH. We conducted a systematic review investigating LT in adult HMH followed by a case report describing evidence of extensive recurrence following complete resection of large right-sided HMH requiring LT.

CASE REPORT

A 46-year-old woman with symptomatic large right-hepatic HMH underwent right hemi-hepatectomy with histologic evidence of complete resection. Two and a half years postresection, she presented with abdominal pain and distension; imaging revealed large multi-septated hepatic cystic lesions within the liver suggestive of extensive recurrence of disease with concerns of malignant sarcomatous transformation. After a multidisciplinary team discussion, the lesion was deemed unresectable and the patient was referred for LT. Findings on transplantation included giant multiple hepatic cystic lesions occupying the entire abdomen and histopathological analysis confirmed recurrent HMH with no malignancy. The 6-month follow-up was unremarkable with no signs of postoperative complications or rejection.

CONCLUSION

We identified only 3 reported adult unresectable HMH cases in the English literature requiring LT, with good clinical outcome and no rejection on a 1-year follow-up. To our knowledge, we report the first recurrent HMH that required LT in the English literature. Current evidence suggests possible malignant sarcomatous transformation of those lesions. No guidelines exist on postresection surveillance for HMH; however, given their malignant potential, we suggest a benefit of imaging-based surveillance following HMH resection. Offering LT for nonresectable or recurrent HMH is a feasible treatment modality with a reported good outcome.

Mesenchymal Hamartoma in Children: A Diagnostic Challenge

Mesenchymal hamartoma is a benign tumor of the liver with a poorly understood pathogenesis. It is uncommon in older children, especially after 2 years of age. The signs and symptoms may be nonspecific; therefore, a high index of suspicion is required for diagnosis and treatment. We report a 5-year-old previously healthy male who presented with acute abdominal pain, fatigue, and fever. He was diagnosed with pneumonia initially and treated with antibiotics. A computed tomography (CT) scan done for evaluation of his persistent abdominal pain demonstrated a hepatic mass. Follow-up magnetic resonance imaging (MRI) of the liver demonstrated multiple serpiginous tubular-type structures, read as possible Caroli syndrome. He had a normal abdominal examination and normal biochemistries including alanine aminotransferase, aspartate aminotransferase, gamma-glutamyl transferase, alkaline phosphatase, and alpha-fetoprotein. He was referred to our institution for second opinion. On further review of his imaging studies, the lesion was thought to be a mesenchymal hamartoma. He subsequently underwent resection of the mass. Pathology confirmed the diagnosis of mesenchymal hamartoma.

[Mesenchymal abdominal tumors in children]

Mesenchymal tumors in childhood comprise benign and malign entities and differ regarding typical sites of manifestation, age peak and clinical symptoms. In some cases biopsy is mandatory. If nephroblastoma is a possible diagnosis, biopsy must be avoided by all means in order to avoid biopsy tract metastasis. Imaging is used to narrow the differential diagnosis, describe the exact extent of the lesion and deliver complete staging. In pediatric patients sonography and MRI are the most important imaging modalities. Low-dose CT of the thorax serves for assessment of possible pulmonary metastases.

Liver transplantation as definitive treatment of an unresectable mesenchymal hamartoma in a child with Beckwith-Wiedemann Syndrome

Mesenchymal liver hamartomas are benign tumors that can cause life-threatening abdominal distension and carry a risk for malignant transformation. In this case report, we describe a 13-month-old male with Beckwith–Wiedemann Syndrome (BWS) who presented with multiple mesenchymal liver hamartomas causing severe intra-abdominal mass effect. Imaging revealed six large multi-locular cystic lesions, ranging from 3.8 to 8.9 cm in diameter. The large size and spread of the tumors necessitated liver transplantation for complete removal. The patient successfully underwent cadaveric piggyback liver transplantation at 25 months of age. He was alive at 16-month follow-up without evidence of tumor recurrence or graft rejection. Histological examination of the hepatic masses revealed mucinous epithelial lining and abundant hepatocytes in varying stages of differentiation, supporting the diagnosis of mesenchymal hamartoma. To the best of our knowledge, this is the first reported case of liver transplantation in a patient with BWS as definitive treatment for unresectable mesenchymal liver hamartoma.

A 4 and a half years old boy with mesenchymal hamartomas in the left lateral lobe of the liver: A case report and literature review

RATIONALE

Mesenchymal hamartomas of the liver is one type of rare liver tumor.

PATIENT CONCERNS

Mesenchymal hamartomas of the liver (MHL) is rarely reported in the left lobe of the liver in children who are more than 2 years old. It is difficult to distinguish it from liver lesions such as hepatoblastoma in children, and hepatocellular carcinoma and focal nodular hyperplasia in adults. In addition, it is hard to correctly diagnose it without pathological examination.

DIAGNOSES

Mesenchymal hamartomas of the liver.

INTERVENTIONS

This patient underwent an operation assisted by the Da Vinci surgical system and the tumor was completely resected.

OUTCOMES

No tumor recurrence or metastasis was observed 14 months after operation.

LESSONS

MHL is a benign tumor that is difficult to diagnose due to the lack of specific clinical symptoms and signs. The management of MHL remains controversial. To achieve a good long-term outcome, complete resection of MHL is recommended.