[Liver resections for primary liver malignancies. Personal results and analysis of the literature]

Staginglaparoskopie in der Onkologie

The availability of more treatment options for gastrointestinal cancer requires precise and reliable pretherapeutic staging. Despite impressive technical progress in modern imaging procedures, this high level of staging quality is not yet warranted in all instances. Visual exploration of the abdominal cavity in extended diagnostic laparoscopy (EDL), including surgical dissection of areas which are primarily inaccessible, biopsy retrieval, and laparoscopic ultrasound, is superior in the diagnostic workup of early peritoneal carcinomatosis and (small) liver metastases. It is helpful to evaluate lymph node infliction and local resectability. In esophageal carcinoma, pretherapeutic EDL is valuable in case of advanced adenocarcinoma of the distal esophagus (AEG I according to Siewert), whereas the incidence of abdominal tumor manifestations in squamous cell carcinoma is too low to perform staging laparoscopy. In advanced gastric cancer, EDL yields relevant additional information in up to 20% of cases. If a multimodal therapeutic strategy is considered, EDL should be obligatory at least in prospective therapeutic studies. In carcinoma of the pancreas, EDL is in general not recommended by the majority of centers. Selective use (in particular in advanced cancer with a high probability of local irresectability) is gaining importance. In hepatobiliary malignancy including colorectal metastases, the high yield of additional information by EDL was confirmed in recent studies.

Diagnostic laparoscopy: indications and benefits

BACKGROUND

The increased availability of treatment options for gastrointestinal cancer, necessitates precise preoperative staging. Laparoscopy can be useful for establishing the diagnosis and staging of cancer. However, there is an ongoing discussion as to whether staging laparoscopy provides additional results despite newly developed imaging tools.

METHODS

A systematic review of relevant literature was undertaken. The strength of evidence was classified according to the North of England Evidence Based Guidelines Development Project. Medline and manual searches were carried out to identify all published manuscripts of clinical trials that dealt with staging laparoscopy. Systematic quality review of those publications was used to verify staging accuracy, complications and trocar metastases.

RESULTS

Only one randomized trial was performed in gynaecological cancer. In cervical cancer, as a result of this study, staging laparoscopy remains unproven. In gastrointestinal cancer (oesophageal, gastric, pancreatic, liver and colorectal cancers) only prospective and retrospective observational studies are available with an evidence-based level of grade B. As a result of these trials, staging laparoscopy, in a well-defined group of patients with locally advanced cancer, is recommended.

CONCLUSION

The effects of surgical staging in gynaecological cancer must be kept in mind but cannot be transferred to gastrointestinal cancer in general. Further studies are required to answer those questions.

VP22-mediated intercellular transport of p53 in hepatoma cells in vitro and in vivo

The capacity of VP22 chimeric proteins to spread from the primary transduced cell to surrounding cells could improve gene therapy approaches, especially in cancer therapy. However, there are conflicting data about VP22-mediated intercellular trafficking in different studies. To assess the role of VP22 in gene therapy of hepatocellular carcinomas (HCCs) we constructed expression vectors for N- and C-terminal versions of VP22-p53 fusion proteins and investigated the VP22-mediated shuttle effect in hepatoma cells by cotransfection experiments. VP22-mediated trafficking was not detectable in hepatoma cells in vitro by fluorescence microscopy, but reporter gene transactivation assays demonstrated intercellular trafficking of functional VP22-p53 in vitro. For in vivo experiments, the recombinant adenoviruses Ad5CMVp53 and Ad5CMVp53-VP22 were constructed. In contrast to the in vitro experiments intercellular trafficking of VP22-p53 could be observed in subcutaneous tumors of hepatoma cells by fluorescence microscopy, indicating a stronger shuttle effect in solid tumors compared to cell culture experiments. Because spread of p53-VP22 in liver tumors was correlated with enhanced apoptosis of hepatoma cells VP22-mediated trafficking of potential therapeutic proteins may improve the results of gene therapy of HCCs.

[Diagnosis and therapy of hepatocellular carcinoma]

During the past decade, the diagnostic technologies concerning the hepatocellular carcinoma have been enriched by the vascular doppler ultrasound, the ultrasound echo-enhancing agents and the magnetic resonance tomography. The therapeutic possibilities have been augmented by the percutaneous ethanol instillation therapy, the combination of local therapies with transcatheter arterial embolisation and the more effective after-treatment after transplantation and segment resection. The use of the respective treatment modalities depends on the tumor constellation, the functional liver reserve, the patients general condition and the risk/benefit ratio of the treatment. The quality of life should be optimized because of the poor tumor prognosis. As there have been no real advances in the treatment of hepatocellular carcinoma to date, the prevention and early diagnosis of the tumor in high risk populations is of utmost importance.

[DNA content of the tumor cell. A new prognostic parameter in hepatocellular carcinoma?]

Hepatocellular carcinoma is a heterogeneous disease with considerable differences in malignant behaviour. Some relevant factors for prognosis are known. In this study we analysed DNA ploidy as a potential prognostic parameter. With DNA image cytometry we were able to differentiate between diploid, hypotriploid, triploid, hypertriploid, tetraploid and aneuploid tumours. The best prognosis was for patients with diploid, hypotriploid and tetraploid tumours with a median survival time of 41 months in contrast to 3 months for patients with triploid, hypertriploid or aneuploid tumours. There was a strong correlation between histomorphological parameters and the DNA content. The DNA content of tumour cells may be considerable clinical relevance in hepatocellular carcinoma regarding the decision as to whether or not to perform a resection. In patients with prognostically unfavorable parameters adjuvant oncological therapy may improve the prognosis.