The sentinel lymph node status is an important factor for predicting clinical outcome in patients with Stage I or II cutaneous melanoma.

BACKGROUND: In a cohort of patients, the authors investigated whether and to what extent the sentinel lymph node (SLN) status contributes to predicting the probability of remaining disease free for at least 3 years. In addition, several traditional prognostic factors were analyzed: Breslow thickness, Clark invasion level, ulceration, lymphatic invasion, location, type of the melanoma, and age and gender of the patient. METHODS: In 263 consecutive patients with proven American Joint Committee on Cancer Stages I and II cutaneous melanoma, the triple technique SLN procedure was used, i.e., preoperative visualization of the lymph channels from the initial site of the melanoma toward the SLN by (dynamic) lymphoscintigraphy, intraoperative visualization of those particular lymph channels and lymph nodes with blue dye, and a gamma probe to measure accumulated radioactivity in radiolabeled lymph nodes. Median follow-up time was 48 months (range, 36-84 months). Multivariate logistic regression analysis was performed to examine the influence of the SLN status and several other prognostic factors on a minimum 3-year disease free survival. RESULTS: In 20% of patients, the SLN proved to be tumor positive. For SLN negative patients, the 5-year disease free survival rate was 91% (+/- 2.4%), and for SLN positive patients it was 49% (+/- 9%). Five variables showed a strong and statistically significant independent prognostic association with outcome, i.e., SLN status (P = 0.0007), thickness of primary melanoma (1.01-2.0 mm; P = 0.04), ulceration (P = 0.05), and lymphatic invasion (P = 0.01) of primary melanoma, and age (40-50 years; P = 0.01). CONCLUSIONS: The SLN status-along with Breslow thickness, ulceration, lymphatic invasion, and age--seems to have strong additional value in predicting a minimum 3-year disease free period after the SLN procedure. Patients with a positive SLN have a poorer prognosis than those with a negative SLN.

Clinical significance of translocation.

The gastrointestinal tract, besides being the organ responsible for nutrient absorption, is also a metabolic and immunological system, functioning as an effective barrier against endotoxin and bacteria in the intestinal lumen. The passage of viable bacteria from the gastrointestinal tract through the epithelial mucosa is called bacterial translocation. Equally important may be the passage of bacterial endotoxin through the mucosal barrier. This article reviews the evidence that translocation of both endotoxin and bacteria is of clinical significance. It summarises recent published works indicating that translocation of endotoxin in minute amounts is a physiological important phenomenon to boost the reticuloendothelial system (RES), especially the Kupffer cells, in the liver. Breakdown of both the mucosal barrier and the RES capacity results in systemic endotoxaemia. Systemic endotoxaemia results in organ dysfunction, impairs the mucosal barrier, the clotting system, the immune system, and depresses Kupffer cell function. If natural defence mechanisms such as lipopolysaccharide binding protein, high density lipoprotein, in combination with the RES, do not respond properly, dysfunction of the gut barrier results in bacterial translocation. Extensive work on bacterial translocation has been performed in animal models and occurs notably in haemorrhagic shock, thermal injury, protein malnutrition, endotoxaemia, trauma, and intestinal obstruction. It is difficult to extrapolate these results to humans and its clinical significance is not clear. The available data show that the resultant infection remains important in the development of sepsis, especially in the critically ill patient. Uncontrolled infection is, however, neither necessary nor sufficient to account for the development of multiple organ failure. A more plausible sequelae is that bacterial translocation is a later phenomenon of multiple organ failure, and not its initiator. It is hypothesized that multiple organ failure is more probably triggered by the combination of tissue damage and systemic endotoxaemia. Endotoxaemia, as seen in trauma patients especially during the first 24 hours, in combination with tissue elicits a systemic inflammation, called Schwartzmann reaction. Interferon gamma, a T cell produced cytokine, is thought to play a pivotal part in the pathogenesis of this reaction. This reaction might occur only if the endotoxin induced cytokines like tumour necrosis factor and interleukin 1, act on target cells prepared by interferon gamma. After exposure to interferon gamma target cells become more sensitive to stimuli like endotoxin, thus boosting the inflammatory cycle. Clearly, following this line of reasoning, minor tissue damage or retroperitoneal haematoma combined with systemic endotoxaemia could elicit this reaction. The clinically observed failure of multiple organ systems might thus be explained by the interaction of tissue necrosis and high concentrations of endotoxin because of translocation. Future therapeutic strategies could therefore focus more on binding endotoxin in the gut before the triggering event, for example before major surgery. Such a strategy could be combined with the start of early enteral feeding, which has been shown in animal studies to have a beneficial effect on intestinal mucosal barrier function and in traumatized patients to reduce the incidence of septic complications.