Elevated serum endothelin-1 levels in patients with colorectal cancer; relevance for prognosis.

Background: It has been demonstrated that the Doppler Perfusion Index (DPI) is increased in patients who are at risk of developing liver metastases from colorectal cancer. It has been postulated that a circulating hormonal factor is involved in the relative vasoconstriction throughout the splanchnic bed. Endothelin-1 (ET-1), a potent vasoconstrictor which has been associated with tumor growth and is produced by colorectal tumors, may play an important role in this phenomenon.

[Summary of the guideline 'Sentinel node biopsy in breast cancer.' Dutch Work Group 'Sentinel Node Biopsy for Breast Cancer'].

The team Sentinel Node Biopsy Breast Cancer issued guidelines for the performance of the sentinel node procedure. The team took into account the problems resulting from the introduction of the technique. The eligible group consists mainly of women with demonstrated breast cancer with a diameter of < or = 2 cm without palpable axillary nodes.

Clinical value of bile for the detection of mutant K-ras from colorectal liver metastases.

In 25% of patients diagnosed with colorectal cancer, hepatic metastases are not detected at presentation of the colorectal primary but develop during follow-up. Early detection of these metastases may improve the chance of cure by surgical resection. We hypothesised that in patients with occult hepatic metastases, tumour DNA might be detected in bile which could be collected during resection of the colorectal primary.

Quantitative measurement of telomerase reverse transcriptase (hTERT) mRNA in urothelial cell carcinomas.

Telomerase reverse transcriptase (hTERT) messenger RNA has been detected in 95% of bladder tumors using RT-PCR. In this study, we quantified the expression of hTERT in 35 bladder urothelial cell carcinomas and in 6 normal bladder epithelia using a real-time quantitative PCR assay. hTERT expression was detected in all 35 urothelial cell carcinomas of varying grade and stage, but not in normal tissue samples.

Real-time quantification of human telomerase reverse transcriptase mRNA in tumors and healthy tissues.

Background: Expression of the hTERT gene, which codes for the catalytic subunit of telomerase, is associated with malignancy. We recently developed a real-time reverse transcription-PCR assay, based on TaqMan technology, for accurate and reproducible determination of hTERT mRNA expression (Lab Investig 1999;79:911-2). This method may be of interest for molecular tumor diagnostics in tissues and corresponding body fluids, washings, or brushes.

New protocol for DNA extraction of stool.

Present methods for DNA isolation of stool have various limitations such as the amount of stool used, the requirement of lavage fluids or the use of fresh stool. In this paper, a new method is described for the isolation of human nucleic acids from stool, which is independent from the moment of collection. Fecal samples as dry as possible were collected from 75 patients; two grams of stool were mixed with a lysis buffer containing phenol.

Screen-detected breast cancers have a lower mitotic activity index.

We know that screening for breast cancer leads to detection of smaller tumours with less lymph node metastases. Could it be possible that the decrease in mortality after screening is not only caused by this earlier stage, but also by a different mitotic activity index (MAI) of the tumours that are detected by screening? Is MAI a prognostic factor for recurrence-free survival? A retrospective study was carried out of 387 patients with breast cancer, treated at the University Hospital Nijmegen between January 1992 and September 1997. Ninety patients had screen-detected breast cancer, 297 patients had breast cancers detected outside the screening programme.

Intraoperative lymphatic mapping and the sentinel node concept in colorectal carcinoma.

Background: Orderly progression of nodal metastases has been described for melanoma and breast cancer. The first draining lymph node, the sentinel node, is also the first to contain metastases and accurately predicts nodal status. The aim of this study was to assess the feasibility of lymphatic mapping and sentinel node biopsy in colorectal cancer.

[A role for cryosurgery in the treatment of non-resectable liver metastases of colorectal neoplasms].

Liver metastases occur in over 40% of patients with colorectal carcinomas. The best prospect of cure is achieved by resection of the metastases. However, only 10-15% of the patients with hepatic metastases are estimated to be candidates for resection.

[The sentinel node biopsy in patients with breast cancer: recommendations for the introduction of this procedure. Dutch Working Group Sentinel Node Biopsy in Breast Cancer].

Sentinel node biopsy may be useful in the staging of breast cancer. In experienced hands presence or absence of metastasis in the sentinel node accurately predicts the nodal status and in patients with a negative sentinel node biopsy axillary dissection may be avoided. The technique, however, shows a clear learning curve and hasty introduction may lead to an unacceptable rate of false negative biopsies.

Detection of tumour DNA in serum of colorectal cancer patients.

Circulating tumour DNA has previously been detected in serum and plasma of patients with lung cancer and head and neck cancer. These observations could potentially lead to new, specific and non-invasive tools for diagnosis, prognosis and follow-up in neoplastic disease, if found to be a more general phenomenon. To test if tumour DNA is also present in serum of patients with colorectal cancer, we selected 14 colorectal cancer patients with advanced disease.

[Transanal resection of large sessile rectal polyps].

Objective: To assess the safety and effectiveness of transanal resection of large rectal adenomas.

Design: Retrospective.

Setting: Department of Surgery, University Hospital Maastricht, the Netherlands.

Changes in E-cadherin immunoreactivity in the adenoma-carcinoma sequence of the large bowel.

We have used an avidin-biotin immunoperoxidase technique to localise epithelial cadherin (E-cadherin), a calcium-dependent cell-cell adhesion molecule, in 107 paraffin-embedded sections from 93 patients consisting of 24 with colorectal adenoma, 55 with rectal carcinoma and 14 with liver metastases. The corresponding primary colorectal tumours were also studied in these cases. E-cadherin was expressed by normal colorectal epithelial cells with typical membranous staining at the intercellular junctions.

Laparoscopic cholecystectomy: a new trend in the management of gallstone disease.

The results of the first 100 consecutive patients who underwent laparoscopic cholecystectomy in our hospital are described. The procedure was completed in 93 cases, and 7 cases (7%) were converted to open cholecystectomy. Of these conversions six were elective because of extensive adhesions, and one conversion was enforced because of instrument failure.

Cellular proliferation at the site of organ allografts and the influence of immunosuppressive therapy.

In this study we investigated cellular proliferation of T cells and macrophages at the site of rat cardiac allografts and determined the influence of immunosuppressive therapy on the proliferative characteristics of these cell types. A bromodeoxyuridine-labeling technique was used that allowed both the accurate detection of proliferative activity and the phenotypic characterization of cellular infiltrates within grafted tissues. In untreated recipients (BN----Lewis), T cytotoxic/suppressor cells as well as T helper cells showed proliferative activity at the site of the graft.

Inhibitory effect of corticosteroids on the secretion of tumour necrosis factor (TNF) by monocytes is dependent on the stimulus inducing TNF synthesis.

The cytokine tumour necrosis factor (TNF) is believed to be involved in the pathophysiology of several human disease states, both septic and non-septic. Different pathways of induction are involved in the generation ofTNF in these disease states. We therefore used four different stimulatory agents, lipopolysaccharide, phorbol myristate acetate, silica quartz, and anti-human IgG antibody to study the influence of the corticosteroids prednisolone and budesonide on the secretion of TNF by human monocytes.

The effect of steroids on the regulation of major histocompatibility complex-class II expression on nonlymphoid tissue.

The induction of MHC-class II antigens on human nonlymphoid tissues plays an essential role during the inhibition and augmentation of the immune response. Steroids have long been shown to possess strong immunosuppressive properties and successful steroid treatment has been associated with the absence of MHC-class II antigens on grated tissues. In this study we more specifically investigated the effect of steroids on the regulation of MHC-class II expression on nonlymphoid tissue.