[Resectable colorectal liver metastases: pro neoadjuvant therapy - contra neoadjuvant therapy]. / Resektable Lebermetastasen beim kolorektalen Karzinom: pro neoadjuvante Therapie - contra neoadjuvante Therapie.

Approximately one third of patients with colorectal cancer (CRC) present with metastases confined to the liver only. In 15 % of these patients the metastases are primarily resectable. After resection of colorectal liver metastases the 5-year survival rate is 25 - 40 %. The EORTC trial of Nordlinger et al. has examined the role of perioperative/neoadjuvant chemotherapy of resectable liver metastases and found in the subgroup of resected patients a significant improvement in disease-free survival through chemotherapy. The results were not significant in the intent-to-treat population. Possible arguments pro neoadjuvant therapy of resectable liver metastases are the early eradication of disseminated tumour cells, the identification of a worse prognosis tumour biology in the individual patient and the higher dose density which can be achieved preoperatively versus postoperatively. Arguments against preoperative chemotherapy are the chemotherapy-induced hepatotoxicity and related increase in perioperative morbidity, the risk of achieving a complete remission of lesions which then cannot be detected intraoperatively and the uncertain optimal duration of chemotherapy. Especially surgical oncologists in Germany do not consider the neoadjuvant treatment of resectable liver metastases as a standard of care. In summary, because of the lack of level 1 evidence, patients with resectable liver metastases of colorectal cancer should be discussed within interdisciplinary tumour boards together with surgeons, gastroenterologists and medical oncologists. Potentially, overall survival data of the EORTC trial which is expected for late 2010 could change the level of evidence.

[Surgical therapy of benign liver tumors]. / Chirurgische Therapie der benignen Lebertumoren.

Benign liver tumors are being detected more frequently due to the widespread use of ultrasound and complementary methods and due to improvements in diagnostic accuracy. In the case of a reliable diagnosis of asymptomatic hemangioma or focal nodular hyperplasia surgery is not indicated. Hepatic adenoma of considerable size should be resected primarily based on the risk of rupture. Improvements in diagnostic imaging as well as the optimization of surgical procedures with extremely low complication rates permit an individualized management strategy founded on evidence-based algorithms. In the case of an equivocal diagnosis, we advocate low-risk tumor resection instead of tumor biopsy due to the inherent complication rates of hemorrhage or tumor-cell dissemination and possible misleading histology.

[Frequency and significance of APC gene mutations in malignant degeneration of Barrett esophagus]. / Frequenz und Bedeutung von APC Genmutationen in der malignen Degeneration des Barrett-Osophagus.

The frequency and importance of APC gene mutations in patients with adenocarcinoma in Barrett's esophagus were evaluated. Tissue samples were obtained by endoscopic biopsy or after surgery in 43 patients. DNA analysis was performed with PCR SSCP and DNA sequencing of the mutation cluster region (Exon 15) of the APC gene. Our analysis demonstrated an infrequent occurrence of APC gene mutations in Barrett's cancer (n = 3) and dysplastic Barrett's mucosa (n = 1). Therefore, the functional significance of the frequently observed APC allelic losses (LOH) must be questioned, as a single allelic loss is not sufficient for a complete gene inactivation. It might however be, that a target gene responsible for the molecular pathogenesis of Barrett's cancer is located outside the APC region on chromosome 5q21. 5q allelic losses could however, serve as a marker for the malignant potential of Barrett's epithelium, as they occur with a high frequency in an early stage of carcinogenesis.