Pretreatment prognostic factors and treatment results in children with hepatoblastoma: a report from the German Cooperative Pediatric Liver Tumor Study HB 94

The emerging family of hepatoblastoma tumours: from ontogenesis to oncogenesis

The identification of distinct types and subtypes of hepatoblastoma has led to a successful classification of these lesions. In recent years, and particularly within large tumour trials, the spectrum of paediatric epithelial liver tumours has increased. This, together with the need for defining clinically relevant risk groups, will require a new approach to defining and classifying these cancers. Furthermore, an impressive amount of molecular biological information on liver ontogenesis and growth regulation of hepatic tumours has recently accumulated, which will allow the development of a comprehensive classification system with particular emphasis on prognostics. In this review, novel findings relating to these issues are discussed.

Effects of P-glycoprotein modulation on the chemotherapy of xenotransplanted human hepatoblastoma

Multidrug resistance (MDR) contributes to limited treatment results in human hepatoblastoma (HB). The MDR1 gene and its product P-glycoprotein (P-gP) has been identified as important factor in this development. In other tumors, P-gP modulation leads to a restored chemosensitivity of the cells. The aim of this study was to analyze the P-gP-modulating effects of PSC 833, a cyclosporine derivate, and verapamil on the chemotherapy of HB in vivo. HB from 2 patients were transplanted subcutaneously into nude mice NMRI (nu/nu). Animals were divided into 7 groups: Group 1 (Control); Group 2 (CDDP); Group 3 (DOXO); Group 4 (DOXO + verapamil); Group 5 (DOXO + PSC 833); Group 6 (CDDP + verapamil); and Group 7 (CDDP + PSC 833). If DOXO was administered (regardless of the combination), the dose was two times 60 mg/m2. If CDDP was administered, the dose was two times 27 mg/m2. When the chemosensitizers were administered, the doses for PSC 833 and for verapamil were four times 5 mg/kg body-weight. In the combined treatment groups the chemosensitizers were given ten minutes prior to CDDP and DOXO. Tumor volume developments and a-fetoprotein (AFP) alterations were assessed. Relative expression levels of the MDR1 gene after treatment were determined using a semiquantitative rT-PCR approach. In a mixed HB, both chemosensitizers combined with DOXO or CDDP produced a significant reduction of tumor growth (p = .0001-.00063) and AFP levels (p = .0006-.0128) compared to tumors treated with DOXO or CDDP only. Treatment results were identical to those in a less differentiated pure embryonal HB, but only in one case (DOXO + PSC 833, p = .031) significant. The chemosensitizers had no influence on the MDR1 gene expression. MDR1 modulators improve the efficiency of DOXO and CDDP treatment in xenotransplanted HB. They do not induce a further increase of drug resistance in the tumors. The data provide evidence that chemosensitizers might improve treatment results in patients with advanced or relapsed HB.

Leberkarzinome und Lebermetastasen

High dosage regional chemotherapy, chemoembolization and other methods of regional treatment are commonly used to treat unresectable primary liver malignancies and liver metastases. In liver malignancies of childhood neoadjuvant chemotherapy is successfully combined with surgical treatment. Chemotherapy and local tumor ablation lead to characteristic histomorphologic changes: Complete destruction of the tumor tissue and its vascular bed is followed by encapsulated necroses. After selective eradication of the tumor cells under preservation of the fibrovasular bed the tumor is replaced by hypocellular edematous and fibrotic tissue. If completely damaged tumor tissue is absorbed quickly, the tumor area is replaced by regenerating liver tissue. Obliterating fibrohyalinosis of tumor vessels, and perivascular edema or necrosis indicate tissue damage along the vascular bed. Degenerative pleomorphism of tumor cells, steatosis, hydropic swelling and Malloryhyalin in HCC can represent cytologic findings of cytotoxic cellular damage. Macroscopic type of HCC influences significantly the response to treatment. Multinodular HCC often contain viable tumor nodules close to destroyed nodules after treatment. Encapsulated uninodular tumors undergo complete necrosis much easier. Large size and a tumor capsule limitate the effect of percutaneous injection of ethanol into HCC. In carcinomas with an infiltrating border, especially in metastases of adenocarcinomas and hepatic cholangiocarcinoma cytostatic treatment damages the tumor tissue mainly in the periphery. Nevertheless the infiltrating rim, portal veins, lymphatic spaces and bile ducts as well as the angle between liver capsule, tumor nodule and bordering parenchyma are the main refugees of viable tumor tissue even after high dosage regional chemotherapy. This local resistance is caused by special local conditions of vascularization and perfusion. These residues are the source of local tumor progression and distant metastases. Besides intrinsic cellular mechanisms architectural, and microenvironmental factors relevantly limitate the effect of intensive locoregional therapy.

Etoposide, cisplatin, epirubicin chemotherapy in the treatment of pediatric liver tumors

To discuss the potential benefit of a chemotherapy regimen including etoposide (etoposide, cisplatin, epirubicin [EPE]), the authors report a single-institutional experience regarding 13 children with hepatoblastoma (HB) and 7 with hepatocellular carcinoma (HCC). Chemotherapy achieved partial response in 8/9 HB and in 4/5 HCC. Eight initially unresectable HB subsequently had liver resection. Event-free survival and overall survival at 5 years were 84 and 88% for HB (non-metastatic cases: 91 and 100%), 29% for HCC. EPE chemotherapy seems to be effective in the treatment of childhood malignant liver tumors. Etoposide could be suggested as part of intensive multidrug regimens for HCC and high-risk HB.

The current management of hepatoblastoma: a combination of chemotherapy, conventional resection, and liver transplantation

OBJECTIVE

To review our experience in the management of children who present with hepatoblastoma.

STUDY DESIGN

Thirty patients treated for hepatoblastoma at a single institution were reviewed.

RESULTS

Ten patients presented with stage I to stage II disease and underwent resection. Seventeen presented with stage III disease; two underwent initial resection of which one required rescue transplantation. The remaining 15 underwent biopsies, which were followed by chemotherapy. Nine patients had a reduction in tumor size and underwent conventional resection. One required rescue transplantation for residual disease. Five patients underwent primary transplantation for unresectable disease. One patient expired during chemotherapy. Three patients presented with stage IV disease and underwent biopsies, which were followed by chemotherapy. One patient responded but required "rescue" transplantation after conventional resection. Seven patients underwent aggressive conventional resection (trisegmentectomy or central liver resection); three had positive surgical margins and underwent transplantation. One developed recurrent disease. Five-year survival was 82.5% +/- 7.1%. There was no operative mortality during surgical therapy. All transplant recipients were tumor free, but one died from lymphoma 7 years post-transplant.

CONCLUSION

Chemotherapy may reduce tumor size, allowing for conventional resection. If aggressive resection is necessary or bi-lobar disease persists, primary transplantation is recommended.

Three-dimensional visualization and virtual simulation of resections in pediatric solid tumors

PURPOSE

Three-dimensional visualization of solid tumors is possible because of high-resolution computed tomography and magnetic resonance imaging scans. However, additional preoperative information is often desirable in complex malignancies. For the first time, the authors present a model of preoperative 3-dimensional visualization and virtual resections in pediatric solid tumors.

METHODS

Image analysis of various pediatric tumors was performed using the research software HepaVision2 (MeVis, Bremen). Organs, tumors, and the vascular system were extracted from multislice computed tomography scans. After hierarchical analysis of the vascular system, territories supplied or drained by the major vascular branches were calculated. Results were explored and virtual resections of organs were carried out using the research software InterventionPlanner (MeVis, Bremen). Data were correlated to intraoperative findings.

RESULTS

Four hepatic malignancies, 4 renal tumors, and 3 other neoplasms were analyzed. The technique of 3-dimensional visualization was feasible for all investigated children (mean age 5 years and 9 months). Spatial relations between physiological and pathological structures were identified, and anatomical structures (vessels, tumor tissue, and organ parenchyma) were determined using colorimetric encoding. Virtual simulations of tumor resection were used successfully for planning of surgical procedures in the hepatic and renal tumors.

CONCLUSIONS

The technique of 3-dimensional tumor visualization and virtual simulation of tumor resections provides the basis for a successful planning of complex tumor resections in children. The efficiency of these techniques should be further analyzed in series with higher numbers and differentiations of tumors.

Effect of postoperative chemotherapy on the serum alpha-fetoprotein level in hepatoblastoma

PURPOSE

It is generally accepted that postoperative chemotherapy does not affect the serum alpha-fetoprotein (AFP) level. The authors report on 3 patients who supposedly showed chemotherapy-related changes in their AFP levels after operation.

METHODS

This study included 3 patients with hepatoblastoma (1 case of PRETEXT III and 2 cases of PRETEXT IV).

RESULTS

One patient with PRETEXT III underwent a complete tumor resection, and the postoperative AFP level decreased until it reached the normal range. However, he consistently exhibited a transient, 2- to 3-fold increase in the AFP after each course of chemotherapy for 3 courses. The chemotherapy regimen had to be stopped because of drug-induced encephalopathy, but he has been followed up for 5 years without any evidence of recurrence, and his AFP level has also remained stable and in the normal range. Two patients with PRETEXT IV, who underwent a curative tumor resection, also showed similar chemotherapy-related changes in AFP levels. Both of these cases were observed only after the administration of routine postoperative chemotherapy instead of administering further high-dose chemotherapy. The AFP level remained stable for 17 months and 7 months after the cessation of chemotherapy in 2 cases, respectively.

CONCLUSIONS

Regarding the postoperative chemotherapy of hepatoblastoma, we have to pay close attention to both the AFP status during chemotherapy as well as the absolute AFP level.

High expression of telomerase is an independent prognostic indicator of poor outcome in hepatoblastoma

Telomerase, an enzyme related with cellular immortality, has been extensively studied in many kinds of malignant tumours for clinical diagnostic or prognostic utilities. Telomerase activity is mainly regulated by the expression of hTERT (human telomerase reverse transcriptase), which is a catalytic component of human telomerase. To evaluate whether the levels of hTERT mRNA provides a molecular marker of hepatoblastoma malignancy, we examined hTERT mRNA expression levels in the primary hepatoblastoma tissues by fluorescent RT–PCR using LightCycler technology and followed up the clinical outcomes in 63 patients listed in the Japanese Study Group of Pediatric Liver Tumor between 1991 and 2002. The hTERT mRNA expression was detected in 61 (96.8%) specimens and their expression levels ranged between 0.1/1000 and 745.1/1000 copies of PBGD gene that was used as an internal control. Among these cases, frozen 39 tumour samples and 14 adjacent noncancerous liver tissues were analysed for semiquantitative telomerase assay. In the 39 tumour samples, the levels of telomerase activity ranged between 0.11 and 2709 TPG and 12 (30.7%) had high telomerase activity (>100 TPG), whereas only nine of 14 noncancerous liver tissue samples showed telomerase activity which was less than 1.0 TPG. The levels of telomerase activity were significantly correlated with the levels of hTERT mRNA expression (P<0.001). The frequency of high hTERT mRNA expression and/or high telomerase activity did not significantly associate with the clinicopathological factors except for stage of disease. The prognosis of the patients with high hTERT mRNA expression was significantly worse than that of others (P<0.01), as was the patients with high telomerase activity (P<0.01). Multivariate analysis indicated that high levels of hTERT mRNA expression as well as telomerase activity are independent prognosis-predicting factors in patients with hepatoblastoma.

Association between surgical margins and long-term outcome in advanced hepatoblastoma

BACKGROUND

Many patients with hepatoblastoma present with unresectable disease. Neoadjuvant therapy has improved resectability rates to as high as 70% to 90%. Despite this improvement, many patients will be left with tumors that are of borderline resectability. The authors hypothesize that favorable outcomes may be achieved even with resection margins less than 1 cm thus sparing the need for liver transplantation.

METHODS

Between January 1981 and March 2003, 23 patients age less than 16 years with a diagnosis of hepatoblastoma undergoing surgical resection were identified. The clinical characteristics, pathologic resection margins, and survival status were reviewed.

RESULTS

Eighteen (78%) of the patients were alive with no evidence of recurrence at last follow-up. Thirteen (56.5%) had > or =1 cm resection margins, whereas 10 (43.5%) had resection margins less than 1 cm. Eleven (47.8%) presented with PRETEXT III tumors. There was no significant difference in survival rate between resection margins less than 1 cm and > or =1 cm (P =.13; 95% CI 0.91 to 2.61). Thirteen patients (56.5%) presented with synchronous pulmonary metastatic disease, where survival was significantly worse (P =.04; 95% CI 1.10 to 2.50). Subgroup analysis confirmed that margins less than 1 cm did not significantly affect survival after controlling for pulmonary metastatic disease (P =.56; 95% CI 0.71 to 3.61).

CONCLUSIONS

Surgical resection with margins less than 1 cm are associated with survival that is equivalent to resection with margins > or =1 cm. Our findings suggest it is preferable to preserve key structures with a small resection margin and therefore spare the need for liver transplantation in patients with advanced hepatoblastoma.

Risk-adapted treatment for childhood hepatoblastoma. final report of the second study of the International Society of Paediatric Oncology--SIOPEL 2

SIOPEL 2 was a pilot study designed to test the efficacy and toxicity of two chemotherapy (CT) regimens, one for patients with hepatoblastoma (HB) confined to the liver and involving no more than three hepatic sectors ('standard-risk (SR) HB'), and one for those with HB extending into all four sectors and/or with lung metastases or intra-abdominal extra hepatic spread 'high-risk (HR) HB'. SR-HB patients were treated with four courses of cisplatin (CDDP), at a dose of 80 mg/m(2) every 14 days, delayed surgery, and then two more similar CDDP courses. HR-HB patients were given CDDP alternating every 14 days with carboplatin (CARBO), 500 mg/m(2), and doxorubicin (DOXO), 60 mg/m(2). Two courses of CARBO/DOXO and one of CDDP were given postoperatively. Between October 1995 and May 1998, 77 SR-HB (10 of whom were actually treated with the HR protocol) and 58 HR-HB patients were registered and all 135 could be evaluated. Response rates for the entire SR-HB and HR-HB groups were 90% (95% CI 80-96%) and 78% (95% CI 65-87%), and resection rates were 97% (95% CI 87-99%) and 67% (95% CI 54-79%) including several children undergoing liver transplantation. For SR-HB patients, 3-year overall and progression-free survivals were 91% (+/-7%) and 89% (+/-7%) and for the HR-HB group 53% (+/-13%) and 48% (+/-13%), respectively. The short-term toxicity of these regimens was acceptable, with no toxic deaths. A treatment strategy based on CDDP monotherapy and surgery thus appears effective in SR-HB but, despite CT intensification, only half of the HR-HB patients are long-term survivors. For SR-HB patients, the efficacy of CDDP monotherapy and the CDDP/DOXO ('PLADO') combination are now being compared in a prospective randomised trial (SIOPEL 3).