[Extended liver resection in small children under circulatory arrest and "low-flow" cardiopulmonary bypass]

Hepatic colorectal metastases involving infra-hepatic inferior vena cava in high risk patients for extended resection: an alternative method for achieving radical resection in patient with borderline liver remnant

Resection is the only chance of cure for isolated liver metastases from colorectal cancer. In the case of extended parenchymal resections, one crucial point is the ischemic damage to the remnant liver. We report an alternative technique for extremely extended liver resections without total hilar clamping for borderline liver remnants. Two patients presented with invasion of the infrahepatic vena cava, both with an estimated live remnant ≤20 %. The crucial point of the technique is the absence of a portal triad clamping in under beating heart-extracorporeal circulation. In both patients resection margins were free of disease. No signs of liver insufficiency were noted. Survival was more than 2 years in both cases. We believe that aggressive treatment of liver colorectal metastases should be given to all suitable patients. This operation may be added to the techniques that can be offered to these patients.

Impact of pedicle clamping in pediatric liver resection

BACKGROUND

Vascular clamping techniques are commonly used but so far the impact on pediatric liver surgery has not been investigated. The purpose of this study was to analyze pedicle clamping during pediatric liver resection in terms of hepato-cellular injury and blood loss.

METHODS

Sixty-seven children undergoing liver resection were analyzed retrospectively. Vascular clamping was used in 28 cases (PC group), in 39 the resection was performed without clamping (NPC group). Major hepatectomies (resection of more than three segments) were carried out in 88%, minor hepatectomies (resection of three and less segments) in 12% of patients. Twenty-six children underwent extended liver resection. Patient data, liver function tests (LFTs) and blood loss were analyzed statistically.

RESULTS

There were no significant differences in patient preoperative and postoperative data and LFTs between the groups. Within the NPC group the amount of administered fresh frozen plasma (FFP) in total and per kilogram (FFP/kg) was significantly higher (p=0.023 and 0.028) than in the PC group. For patients with extended liver resection, operation times were significantly longer (p=0.016) in the group without vascular clamping (NPCext). In the NPCext group significantly more children required packed red cells, FFP and FFP/kg. LFTs showed no significant differences in all children regardless of vascular clamping.

CONCLUSIONS

For children undergoing liver resection, vascular clamping offers a blood saving surgical technique. Postoperative LFTs were not statistically different, regardless of vascular clamping. Pedicle clamping proved to be a safe method, not associated with an increase in perioperative complications.

Unresectable multifocal hepatoblastoma with cardiac extension: excellent response with HB-94 chemotherapy protocol

A 10-month-old white infant presented with abdominal distention and bilateral scrotal hernia. Imaging studies of the abdomen and thorax showed a huge liver with multiple tumor masses and calcification involving all the segments. There was thrombosis in the inferior vena cava and right atrium. alpha-Fetoprotein was 246,000 IU/mL. HB-94 chemotherapy protocol was started at once due to rapid deterioration of the patient. Surgical biopsy performed after the first IPA (ifosfamide, cisplatin, doxorubicin) course showed hepatoblastoma with macrotrabecular variant. After a second IPA course and 2 courses of carboplatin and etoposide, the boy's clinical condition was excellent with normal alpha-fetoprotein but minimal regression and increased calcification in the tumor mass. Hepatic tumor was unresectable and no surgical intervention was performed. Transplantation could not be performed because of high morbidity and mortality. Despite general agreement that complete surgical resection is the cornerstone of treatment for patients with hepatoblastoma, the patient is in remission with 100% Karnofsky score in the 43 months of diagnosis.

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.

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.

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

BACKGROUND

In the past 20 years, a dramatic improvement in the prognosis of patients with hepatoblastoma (HB) has been achieved by combining surgery with chemotherapy in several national and international trials. A worldwide, unsolved problem remains the treatment of patients with advanced or metastatic HB.

METHODS

The German Cooperative Pediatric Liver Tumor Study HB 94 was a prospective, multicenter, single-arm study. The study ran from January 1994 to December 1998. The protocol assessed the efficiency of chemotherapy consisting of cisplatin, ifosfamide, and doxorubicin (CDDP/IFO/DOXO) and/or etoposide and carboplatin (VP16/CARBO). The prognostic significance of the surgical strategy, pretreatment factors, and tumor characteristics for disease free survival (DFS) were analyzed.

RESULTS

Sixty-nine children with HB were treated in the HB 94 study. The median follow-up of survivors was 58 months (range, 32-93 months). Fifty-three of 69 patients (77%) remained alive, and 16 of 69 patients (23%) died. Long-term DFS was as follows: 26 of 27 patients had Stage I HB, 3 of 3 patients had Stage II HB, 19 of 25 patients had Stage III HB, and 5 of 14 patients had Stage IV. A complete resection of the primary tumor was achieved in 54 of 63 patients (86%). Six children (8%) had no surgical treatment. Twenty-two tumors were resected primarily, and 41 children underwent surgery after initial chemotherapy. Two children underwent liver transplantation. There was no perioperative death. Forty-eight children received primary chemotherapy with CDDP/IFO/DOXO. Forty-one of 48 children achieved partial remission after CDDP/IFO/DOXO. Eighteen children with advanced or recurrent HB underwent VP16/CARBO chemotherapy, with a response achieved by 12 children. The relevant pretreatment prognostic factors were growth pattern of the liver tumor (P = 0.0135), vascular tumor invasion (P = 0.0039), occurrence of distant metastases (P = 0.0001), initial alpha-fetoprotein level (P = 0.0034), and surgical radicality (P < 0.0001).

CONCLUSIONS

The current results underline the necessity of preoperative chemotherapy in all children with HB. Complete tumor resection is one of the main prognostic factors.