Simultaneous Resection of High-risk Liver Tumors and Pulmonary Metastases in Children

Modelling the impact of liver regeneration on hepatoblastoma patient-derived-xenograft tumor growth

BACKGROUND

Twenty percent of children with hepatoblastoma (HB) have lung metastasis at diagnosis. Treatment protocols recommend surgical removal of chemotherapy-refractory lung nodules, however no chronological order is established. As hepatectomy is followed by release of growth factors, it has been proposed that partial hepatectomy (PH) could boost local or distant residual tumor growth.

METHODS

To evaluate the impact of PH on distant tumor growth, PH was performed in mice subcutaneously implanted with a HB patient-derived xenograft (PDX). The influence of PH on tumor growth at primary site was assessed by performing PH concomitantly to HB PDXs orthotopic implantation.

RESULTS

Subcutaneously implanted HB PDX failed to show any influence of hepatectomy on tumor growth. Instead, intrahepatic tumor growth of one of the 4 HB PDXs implanted orthotopically was clearly enhanced. Cells derived from the hepatectomy-sensitive HB PDX exposed to hepatic growth factor (HGF) showed increased proliferation rate compared to cells derived from a hepatectomy-insensitive model, suggesting that the HGF/MET pathway could be one of the effectors of the crosstalk between liver regeneration and HB growth.

CONCLUSION

These results suggest that hepatectomy can contribute to HB growth in some patients, further studies will be necessary to identify biomarkers predictive of patient risk of PH-induced HB recurrence.

IMPACT

Key message: Cytokines and growth factors secreted following partial hepatectomy can contribute to intrahepatic tumor growth in some hepatoblastoma models. What does it add to the existing literature: It is the first article about the impact of liver regeneration induced by partial hepatectomy on hepatoblastoma local or distant tumoral growth in nude mice. What is the impact: It is important to identify the secreted factors that enhance tumor growth and to define biomarkers predictive of patient risk of partial hepatectomy-induced hepatoblastoma recurrence.

A Surgical Approach to Pulmonary Metastasis in Children

Decisions regarding the role of surgery in pulmonary metastasis need to take into account histology and biology of the cancer. Response to chemotherapy and radiotherapy, balanced with toxicities, factors into decisions about metastasectomy. The less sensitive the tumor is to adjuvant therapy, the more likely that metastasectomy may be beneficial. Broad principles include the following: the aims of resection are localized resections with clear margins, with the aim of preserving adequate lung volume; unnecessary toxic therapy sometimes is avoided with accurate diagnosis; tumor type is of utmost importance; and number of metastases and the disease-free interval are not contraindications to metastasectomy.

How Do Synchronous Lung Metastases Influence the Surgical Management of Children with Hepatoblastoma? An Update and Systematic Review of the Literature

Approximately 20% of children with hepatoblastoma (HB) have metastatic disease at diagnosis, most frequently in the lungs. In children with HB, lung metastatic disease is associated with poorer prognosis. Its treatment has been approached with a variety of methods that integrate chemotherapy and surgical resection. The timing and feasibility of complete extirpation of lung metastases, by chemotherapy and/or metastasectomy, is crucial for the surgical treatment of the primary liver tumor, which can vary from major hepatic resections to liver transplantation (LT). In children with unresectable HB, which can be surgically treated only by LT, the persistence of unresectable metastases after neoadjuvant chemotherapy excludes the possibility of recurring to LT with consequent negative impact on patients' outcomes. Due to limited evidence and experience, there is no consensus amongst oncologists and surgeons across institutions regarding the surgical treatment for HB with synchronous metastatic lung disease. This narrative review aimed to update the current management of pulmonary metastasis in children with HB and to define its role in the decision-making strategy for the surgical approach to primary liver tumours.

POST-TEXT III and IV Hepatoblastoma: Extended Hepatic Resection Avoids Liver Transplantation in Selected Cases

OBJECTIVE

To analyze the outcome of hepatoblastoma (HB) patients presenting with post treatment extent of disease (POST-TEXT) stages III and IV after neoadjuvant chemotherapy.

BACKGROUND

Primary liver transplantation has been advocated as surgical treatment for children with HB involving 3 or 4 sectors at diagnosis. However, in some cases, tumors seem resectable after chemotherapy through aggressive use of nontransplant surgical procedures.

METHODS

Data of 27 HB patients were reviewed, undergoing extended liver resection for POST-TEXT III or IV tumors after chemotherapy between 1992 and 2015. Median follow-up was 58 months (range 9-188).

RESULTS

Median age at surgery was 18.2 months (interquartile range 10.8-32.5). Staging of the children after chemotherapy revealed POST-TEXT III in 21 and POST-TEXT IV in 6 cases. In 2 children, the hepatic resection was performed under cardiopulmonary bypass because of extended vena cava thrombosis; in 2 patients, a simultaneous sternotomy was performed for resection of bilateral lung metastases. The 5-year overall survival rate was 80.7%.

CONCLUSIONS

Aggressive surgical resection is a successful approach in some patients with POST-TEXT III and IV HB who otherwise would be candidates for liver transplantation. These children should undergo central review and should be surgically managed at centers of excellence for pediatric liver surgery. Despite challenging surgical procedures and complex clinical courses, the patients benefit from avoidance of morbidities of organ transplant. However, preparation of backup liver transplantation should be considered in selected cases.

Relapsed hepatoblastoma confined to the lung is effectively treated with pulmonary metastasectomy

BACKGROUND

In children diagnosed with hepatoblastoma (HB), the lungs are the most common site of metastasis at both initial presentation and relapse. Previous studies have encouraged pulmonary metastasectomy to achieve a disease-free state after resection of the primary hepatic lesion. However, there is no consensus about how to manage recurrent pulmonary metastasis.

PROCEDURE

A retrospective, multi-institutional review was performed from 2005 to 2014 to identify HB patients ≤18years of age who had disease recurrence associated with pulmonary metastases alone.

RESULTS

Ten patients between the ages of 8 and 33months were identified. Pulmonary metastatic recurrence was detected by measuring alpha-fetoprotein (AFP) levels and/or with CT scans of the chest. All patients subsequently underwent pulmonary metastasectomy without post-operative complications. At last follow-up, 8 patients were alive and had normal AFP levels. The 8 survivors had a median follow-up from therapy completion of 18.5months. Two patients who presented with extrapulmonary recurrence subsequently died of treatment refractory disease.

CONCLUSIONS

This review supports surgical resection as a safe and, in the context of multimodal therapy, efficacious approach to manage HB patients who present with isolated pulmonary relapse.