The Waterlow score for risk assessment in surgical patients.

INTRODUCTION: Perioperative scoring systems aim to predict outcome following surgery and are used in preoperative counselling to guide management and to facilitate internal or external audit. The Waterlow score is used prospectively in many UK hospitals to stratify the risk of decubitus ulcer development. The primary aim of this study was to assess the potential value of this existing scoring system in the prediction of mortality and morbidity in a general surgical and vascular cohort. METHODS: A total of 101 consecutive moderate to high risk emergency and elective surgical patients were identified through a single institution database. The preoperative Waterlow score and outcome data pertaining to that admission were collected. The discriminatory power of the Waterlow score was compared against that of the American Society of Anesthesiologists (ASA) grade and the Portsmouth Physiological and Operative Severity Score for the enUmeration of Mortality and morbidity (P-POSSUM). RESULTS: The inpatient mortality rate was 17% and the 30-day morbidity rate was 29%. A statistically significant association was demonstrated between the preoperative Waterlow score and inpatient mortality (p<0.0001) and 30-day morbidity (p=0.0002). Using a threshold Waterlow score of 20 to dichotomise risk, accuracies of 0.84 and 0.76 for prediction of mortality and morbidity were demonstrated. In comparison with P-POSSUM, the preoperative Waterlow score performed well on receiver operating characteristic analysis. With respect to mortality, the area under the curve was 0.81 (0.80-0.85) and for morbidity it was 0.72 (0.69-0.76). The ASA grade achieved a similar level of discrimination. CONCLUSIONS: The Waterlow score is collected routinely by nursing staff in many hospitals and might therefore be an attractive means of predicting postoperative morbidity and mortality. It might also function to stratify perioperative risk for comparison of surgical outcome data. A prospective study comparing these risk prediction scores is required to support these findings.

Pancreatic and peripancreatic somatostatinomas.

BACKGROUND: Somatostatinomas are rare neuroendocrine tumours with an annual incidence of 1 in 40 million. They arise in the pancreas or periampullary duodenum. Most are clinically non-secretory and do not cause the somatostatinoma syndrome. Many are metastatic at presentation and their management is typically multimodal. CASE HISTORIES: Four cases of somatostatinoma are described. Two patients with periampullary disease presented with biliary obstruction, one with frank jaundice and one with incidental bile duct obstruction on investigation of hepatitis B. Each patient had type 1 neurofibromatosis and resection of the somatostatinoma by means of a pylorus-preserving proximal pancreaticoduodenectomy has resulted in long-term survival. Another two patients with metastatic pancreatic somatostatinomas presented with abdominal pain. Contrasting management illustrates current treatment strategies that are dependent in part on the distribution of the disease. DISCUSSION: The pathophysiology, presentation, clinical associations and role of diagnostic imaging are discussed for periampullary and pancreatic neuroendocrine tumours. Operative treatment has an important role in both the curative and palliative settings in conjunction with appropriate medical treatments and these are described. Management options depend on the extent of the disease and the cases are used to illustrate the rationale of such strategies.

Laser microdissection expression profiling of marginal edges of colorectal tumours reveals evidence of increased lactate metabolism in the aggressive phenotype.

BACKGROUND: The morphology of the invasive margin in colorectal cancer can be described as either pushing or infiltrative. These phenotypes carry prognostic significance, particularly in node negative disease, and provide an excellent model for the study of invasive behaviour in vivo. METHODS: The marginal edges of 16 stage-matched tumours exhibiting these contrasting growth patterns were microdissected. The extracted mRNA was amplified and hybridised to a 9546 feature oligonucleotide array. Selected differentials were validated using real-time polymerase chain reaction and the protein product was interrogated by using immunohistochemistry. RESULTS: After stringent quality control and filtering of data generated, 39 genes were identified as being significantly differentially expressed between the two types of marginal edge. Several genes involved in cellular metabolism were identified as differentials including lactate dehydrogenase B (LDHB) and modulators of glucose transport. CONCLUSIONS: The LDH expression profile differs between the invasive phenotypes. A hypothesis is proposed in which altered metabolism is a cause of contrasting invasive behaviour independent of the hypoxia-inducible factor mediated hypoxic response, consistent with the Warburg phenomenon.

What factors affect lymph node yield in surgery for rectal cancer?

OBJECTIVE: The detection of lymph node metastases is of vital importance in patients undergoing excisional surgery for rectal cancer as it provides important prognostic information and facilitates decision-making with regards to adjuvant therapy. It has been suggested that patients in whom only a small number of nodes are present in the excised specimen have a worse prognosis, presumably due to inadequate lymphadenectomy and consequent understaging of the disease. The aim of this study was to determine which factors affect the yield of lymph nodes. METHODS: This was a retrospective study of patients who had undergone a resection for histologically proven adenocarcinoma of the rectum. The total number of lymph nodes identified in the excised specimen was recorded in each case. A multivariate analysis was performed to ascertain whether this number was significantly influenced by any of several variables. RESULTS: A total of 167 patients were studied (M:F ratio 107 : 60, median age 70 years). The median number of lymph nodes contained within the resected specimen was 16 (interquartile range 10-21). On univariate analysis a significantly higher yield of lymph nodes was obtained with tumours in the middle third of the rectum (P=0.007), larger tumours (P < 0.001), more locally advanced tumours according to both pT staging (P=0.001) and Dukes' staging (P=0.020), an increased number of involved nodes (P=0.003) and examination by a specialist histopathologist (P=0.003). On multivariate analysis the only significant variables were tumour size (P=0.021), number of positive nodes (P=0.007) and histopathologist (P=0.021). CONCLUSIONS: The number of lymph nodes identified within the excised specimen in patients undergoing resection of a rectal cancer positively correlates with the size of the tumour and is also dependent on the examining histopathologist. In addition, in node-positive patients the number of involved nodes increases with increasing lymph node yield.