Role of FDG-PET in surgical management of patients with colorectal liver metastases.

BACKGROUND: [(18)F]-fluorodeoxyglucose positron emission tomography (FDG-PET) is reported to change the management in 20-56% of patients with recurrent or metastatic colorectal cancer. It is not clear if FDG-PET has a role in all such patients or only a subgroup. The aim of the present study was to assess the influence of FDG-PET on the surgical management of patients with known or suspected colorectal liver metastases. METHODS: Patients undergoing FDG-PET for investigation of known or suspected colorectal liver metastases were identified from a South Australian database. Case notes were reviewed retrospectively to determine the influence of FDG-PET findings on patient management. Findings from FDG-PET scanning were compared with findings from conventional diagnostic investigations and operative findings. RESULTS: Overall, in four of 16 patients (25%) management was influenced by FDG-PET findings. FDG-PET altered management in four of eight (50%) patients with non-diagnostic liver lesions on computed tomography (CT) or with elevated carcinoembryonic antigen levels but no liver lesion on CT. In all eight patients with CT diagnosed resectable liver metastases, the addition of FDG-PET did not influence the management. CONCLUSIONS: The findings support the use of FDG-PET in the assessment of selected patients with suspected colorectal liver metastases and equivocal findings on conventional diagnostic investigation.

The lack of a systemic inflammatory response syndrome supports the safety of pancreatic electrolysis: experimental studies.

BACKGROUND: Per-ductal pancreatic electrolysis is a new minimally invasive ablation treatment. Possible applications include tumor debulking and treatment of chronic pancreatitis. Both solid organ ablation and pancreatitis are associated with the risk of an overwhelming systemic inflammatory response syndrome (SIRS) and multiorgan failure. TNF-alpha and IL1-beta are important cytokine mediators of this response. The aim of this study was to measure the circulating levels of IL1-beta and TNF-alpha following pancreatic electrolytic ablation as a marker of the risk of SIRS complicating per-ductal pancreatic electrolysis. METHODS: Serum TNF-alpha and IL1-beta were measured in six treatment and six control pigs before and after laparotomy and pancreatic electrolytic ablation via a per-ductal approach. RESULTS: There was no significant rise in serum TNF-alpha and IL1-beta in association with per-ductal pancreatic electrolysis. CONCLUSIONS: This study supports the evidence that per-ductal electrolysis is a safe procedure with potential for palliative treatment of pancreatic cancers.

Subtotal hepatectomy: a porcine model for the study of liver regeneration.

BACKGROUND: This study aimed to devise a simple, reproducible method of subtotal hepatectomy in a large animal model. Such an experimental model could be useful in the investigation of liver regeneration and liver insufficiency after partial hepatectomy. Equally, this technique could be used for assessing the effect of artificial liver support systems on both liver function and regeneration. MATERIALS AND METHODS: Twenty pigs were subjected to either 70-80% liver resection (n = 11), or 85-90% liver resection (n = 9), using a simplified technique. RESULTS: Most tolerated the procedure well and showed restoration of full liver volume within 3 weeks. Three animals in the 90% resection group died with significantly raised levels of International Normalized Ratio (INR) and ammonia. CONCLUSIONS: These two techniques have been shown to be easily reproducible and well tolerated by the animals and allow easy assessment of liver function and regeneration in the postoperative period. The deaths in the 90% resection group supports the hypothesis that 90% partial hepatectomy represents a model of critical residual liver parenchyma.

Experimental studies of serum cytokine concentration following pancreatic electrolytic ablation.

BACKGROUND: Pancreatic cancer has a poor prognosis, with symptomatic palliation being the priority in the majority of cases. Alternative palliative techniques, such as local ablation, are under investigation. Palliative per-ductal electrolytic ablation of the pancreas has been reported, in an experimental series. It is important to establish that this technique is associated with low morbidity and mortality if it is to be acceptable. The 'systemic inflammatory response syndrome' (SIRS) is a recognised and serious complication of both acute pancreatitis, and certain locally ablative techniques. This study aimed to determine whether pancreatic electrolytic ablation is associated with an increase in serum IL-1b and TNF-a concentrations, these cytokines playing integral roles in the inflammatory pathway of SIRS. MATERIAL/METHODS: Eight pigs underwent per-ductal electrolytic ablation of the pancreas. Serum samples, taken pre-operatively and post-operatively for two weeks, were analysed for IL-1b and TNF-a concentrations. Variations in cytokine levels were statistically analysed. RESULTS: Post-operative serum IL-1b and TNF-a concentrations did not significantly increase on pre-operative figures. There were no other clinical, biochemical or histological indicators of a SIRS-like phenomenon. CONCLUSIONS: The results from this study suggest that electrolytic ablation of normal pancreas is not associated with either an increase in serum concentrations of IL-1b and TNF-a or a SIRS phenomenon. Although this study has only investigated the serum levels of two cytokines, IL-1b and TNF-a have both been shown to have a central role in the inflammatory cascade that leads to SIRS.

Islet yield remains a problem in islet autotransplantation.

For patients with chronic pancreatitis whose pain is inadequately controlled with opiate analgesia, surgical resection offers a good chance of symptomatic relief. However, the inevitable sequela is type 1 diabetes mellitus and its attendant long-term complications. Islet cell autotransplantation offers a theoretical "cure" for this iatrogenic diabetes but this end point has not been produced consistently in clinical practice. The main factor determining the likelihood of insulin independence after islet autotransplantation is the islet mass that is transplanted. This review examines the factors that affect the functional islet mass available for transplantation. Original articles and reviews from peer-reviewed journals were analyzed following a computer search of the MEDLINE database from 1966 to the present, we extracted mainly level 2 and level 3 data. Although improvements in collagenase consistency and purification techniques and reductions in cold ischemic times have all been shown to improve islet yield, there is still the need to optimize every stage in the islet isolation process. Increasing the proportion of potential islets in the final isolate is of particular importance in chronic pancreatitis because the total mass of islets initially available in the gland might be just sufficient to produce insulin independence after islet autotransplantation. We believe that reducing the warm ischemic time might significantly increase the likelihood of insulin independence after islet autotransplantation.

Surgical management of intractable pain in chronic pancreatitis: past and present.

The surgical management of pain in patients with chronic pancreatitis continues to provide a formidable challenge. Despite recent advances in the area of the pathophysiolgical cause of the symptoms of chronic pancreatitis there is still controversy as to the exact mechanisms that result in pain in both large and small duct disease. In addition, the surgical community has very polarized views as to the correct management of these patients. In this review we have set out to summarize the treatment options available and provide comparative data where available. Data were found following a computer search of the Medline database from 1966 to the present. The information extracted comprises mainly level two and level three data. There is a continuing lack of a "gold standard" in the surgical management of pancreatic pain. This is mainly due to the paucity of randomized controlled trials in the field of pancreatic surgery. With only four randomized controlled trials reported in the world literature it is difficult to state categorically what is the optimal treatment for this difficult group of patients. Until there is increased standardization in the reporting of both the physiological outcomes and quality-of-life issues in the surgical management of chronic pancreatitis this will continue to be the situation.