The laparoscopic modified Sugarbaker technique is safe and has a low recurrence rate: a multicenter cohort study.

BACKGROUND: Parastomal hernia is a frequent complication of intestinal stomata. Mesh repair gives the best results, with the mesh inserted via laparotomy or laparoscopically. It was the aim of this retrospective multicenter study to determine the early and late results of the laparoscopically performed, modified Sugarbaker technique with ePTFE mesh. METHODS: From 2005 to 2010, a total of 61 consecutive patients (mean age = 61 years), with a symptomatic parastomal hernia, underwent laparoscopic repair using the modified Sugarbaker technique with ePTFE mesh. Fifty-five patients had a colostomy, 4 patients an ileostomy, and 2 a urostomy according to Bricker. The records of the patients were reviewed with respect to patient characteristics, postoperative morbidity, and mortality. All patients underwent physical examination after a follow-up of at least 1 year to detect a recurrent hernia. Morbidity rate was 19 % and included wound infection (n = 1), ileus (n = 2), trocar site bleeding (n = 2), reintervention (n = 2), and pneumonia (n = 1). One patient died in the postoperative period due to metastasis of lung carcinoma that caused bowel obstruction. Concomitant incisional hernias were detected in 25 of 61 patients (41 %) and could be repaired at the same time in all cases. A recurrent hernia was found in three patients at physical examination, and in one patient an asymptomatic recurrence was found on a CT scan. The overall recurrence rate was 6.6 % after a mean follow-up of 26 months. CONCLUSION: The laparoscopic Sugarbaker technique is a safe procedure for repairing parastomal hernias. In our study, the overall morbidity was 19 % and the recurrence rate was 6.6 % after a mean follow-up of 26 months. Moreover, the laparoscopic approach revealed concomitant hernias in 41 % of the patients, which could be repaired successfully at the same time.

Cytosolic streaming in vegetative mycelium and aerial structures of Aspergillus niger.

Aspergillus niger forms aerial hyphae and conidiophores after a period of vegetative growth. The hyphae within the mycelium of A. niger are divided by septa. The central pore in these septa allows for cytoplasmic streaming. Here, we studied inter- and intra-compartmental streaming of the reporter protein GFP in A. niger. Expression of the gene encoding nuclear targeted GFP from the gpdA or glaA promoter resulted in strong fluorescence of nuclei within the vegetative hyphae and weak fluorescence in nuclei within the aerial structures. These data and nuclear run on experiments showed that gpdA and glaA are higher expressed in the vegetative mycelium when compared to aerial hyphae, conidiophores and conidia. Notably, gpdA or glaA driven expression of the gene encoding cytosolic GFP resulted in strongly fluorescent vegetative hyphae and aerial structures. Apparently, GFP streams from vegetative hyphae into aerial structures. This was confirmed by monitoring fluorescence of photo-activatable GFP (PA-GFP). In contrast, PA-GFP did not stream from aerial structures to vegetative hyphae. Streaming of PA-GFP within vegetative hyphae or within aerial structures of A. niger occurred at a rate of 10-15 µm s(-1). Taken together, these results not only show that GFP streams from the vegetative mycelium to aerial structures but it also indicates that its encoding RNA is not streaming. Absence of RNA streaming would explain why distinct RNA profiles were found in aerial structures and the vegetative mycelium by nuclear run on analysis and micro-array analysis.

Germination of conidia of Aspergillus niger is accompanied by major changes in RNA profiles.

The transcriptome of conidia of Aspergillus niger was analysed during the first 8 h of germination. Dormant conidia started to grow isotropically two h after inoculation in liquid medium. Isotropic growth changed to polarised growth after 6 h, which coincided with one round of mitosis. Dormant conidia contained transcripts from 4 626 genes. The number of genes with transcripts decreased to 3 557 after 2 h of germination, after which an increase was observed with 4 780 expressed genes 8 h after inoculation. The RNA composition of dormant conidia was substantially different than all the subsequent stages of germination. The correlation coefficient between the RNA profiles of 0 h and 8 h was 0.46. They were between 0.76-0.93 when profiles of 2, 4 and 6 h were compared with that of 8 h. Dormant conidia were characterised by high levels of transcripts of genes involved in the formation of protecting components such as trehalose, mannitol, protective proteins (e.g. heat shock proteins and catalase). Transcripts belonging to the Functional Gene Categories (FunCat) protein synthesis, cell cycle and DNA processing and respiration were over-represented in the up-regulated genes at 2 h, whereas metabolism and cell cycle and DNA processing were over-represented in the up-regulated genes at 4 h. At 6 h and 8 h no functional gene classes were over- or under-represented in the differentially expressed genes. Taken together, it is concluded that the transcriptome of conidia changes dramatically during the first two h and that initiation of protein synthesis and respiration are important during early stages of germination.

Development in Aspergillus.

The genus Aspergillus represents a diverse group of fungi that are among the most abundant fungi in the world. Germination of a spore can lead to a vegetative mycelium that colonizes a substrate. The hyphae within the mycelium are highly heterogeneous with respect to gene expression, growth, and secretion. Aspergilli can reproduce both asexually and sexually. To this end, conidiophores and ascocarps are produced that form conidia and ascospores, respectively. This review describes the molecular mechanisms underlying growth and development of Aspergillus.

The effect of natamycin on the transcriptome of conidia of Aspergillus niger.

The impact of natamycin on Aspergillus niger was analysed during the first 8 h of germination of conidia. Polarisation, germ tube formation, and mitosis were inhibited in the presence of 3 and 10 µM of the anti-fungal compound, while at 10 µM also isotropic growth was affected. Natamycin did not have an effect on the decrease of microviscosity during germination and the concomitant reduction in mannitol and trehalose levels. However, it did abolish the increase of intracellular levels of glycerol and glucose during the 8 h period of germination.Natamycin hardly affected the changes that occur in the RNA profile during the first 2 h of germination. During this time period, genes related to transcription, protein synthesis, energy and cell cycle and DNA processing were particularly up-regulated. Differential expression of 280 and 2586 genes was observed when 8 h old germlings were compared with conidia that had been exposed to 3 µM and 10 µM natamycin, respectively. For instance, genes involved in ergosterol biosynthesis were down-regulated. On the other hand, genes involved in endocytosis and the metabolism of compatible solutes, and genes encoding protective proteins were up-regulated in natamycin treated conidia.

Experimental study of radioimmunotherapy versus chemotherapy for colorectal cancer.

BACKGROUND: Radioimmunotherapy (RIT) has been shown to reduce the incidence of local recurrence of colorectal cancer in an experimental model. The aim of the present study was to investigate the survival benefit of RIT compared with chemotherapy. METHODS: An anastomosis was constructed in male Wag/Rij rats after intraluminal injection of CC531 tumour cells. The therapeutic efficacy of (177) Lu-labelled MG1 (single intravenous dose of 300 MBq/kg, n = 20) was compared with that of 5-fluorouracil-based chemotherapy (6 weekly cycles administered intraperitoneally, n = 20) and no treatment (n = 20). The primary endpoint was survival. Toxicity was monitored by bodyweight measurement. RESULTS: Both chemotherapy and RIT affected bodyweight, but the weight of animals in the RIT group remained significantly higher than in the chemotherapy group (median slope of bodyweight plot 0·48 versus 0·30 g/day; P < 0·001). Kaplan-Meier analysis showed that overall survival in the RIT and chemotherapy groups was significantly better than that in the control group (50 and 46 per cent versus 25 per cent respectively after 170 days; P = 0·024 and P = 0·029). Survival after treatment with RIT did not differ from that after chemotherapy (P = 0·911). CONCLUSION: RIT is as effective as chemotherapy in experimental colorectal cancer.

Intraoperative hyperthermic intraperitoneal chemotherapy after cytoreductive surgery for peritoneal carcinomatosis in an experimental model.

BACKGROUND: The combination of cytoreductive surgery (CS) and hyperthermic intraperitoneal chemotherapy (HIPEC) is the treatment of choice for selected patients with peritoneal carcinomatosis (PC) of colorectal origin. However, it remains to be proven whether the addition of HIPEC to CS is essential for the reported survival benefit. METHODS: Sixty WAG/Rij rats were inoculated intraperitoneally with the rat colonic carcinoma cell line CC-531. Animals were randomized into three treatment groups: CS alone, CS followed by HIPEC (mitomycin 15 mg/m(2) ) and CS followed by HIPEC (mitomycin 35 mg/m(2) ). Survival was the primary outcome parameter. RESULTS: The median survival of rats treated with CS alone was 43 days. Rats receiving HIPEC 15 mg/m(2) and HIPEC 35 mg/m(2) both had a significantly longer median survival of 75 days (P = 0·003) and 97 days (P < 0·001) respectively. Rats receiving HIPEC showed a significantly lower tumour load at autopsy compared with rats treated with CS alone. CONCLUSION: A combination of CS and HIPEC results in longer survival than CS alone in rats with PC of colorectal origin.

Radioimmunotherapy prevents local recurrence of colonic cancer in an experimental model.

BACKGROUND: Radioimmunotherapy (RIT) is suitable for the treatment of microscopic residual disease and might therefore have an adjuvant role after colonic cancer surgery. METHODS: An anastomosis was constructed in male Wag/Rij rats after intraluminal injection of 2 x 10(6) CC531 tumour cells. The biodistribution of (111)In-labelled MG1 monoclonal antibody was assessed after intraperitoneal administration. The therapeutic efficacy of (177)Lu-labelled MG1 (74 MBq per rat), administered on the day of surgery (D0, n = 13) or 5 days later (D5, n = 13), was compared with that of carrier only (n = 13). The primary endpoint was perianastomotic tumour growth 28 days after surgery. RESULTS: (111)In-labelled MG1 preferentially accumulated in perianastomotic CC531 tumours. RIT resulted in a transient reduction in bodyweight in both treatment groups compared with controls, but there were no other signs of clinical discomfort. No macroscopic or microscopic perianastomotic tumour growth was found in eight of 11 animals in the D0 group and 11 of 13 in the D5 group, whereas 11 of 13 controls had macroscopic tumour (P = 0.011 and P = 0.001 respectively). CONCLUSION: This study suggests that RIT may be an effective adjuvant treatment for preventing local recurrence after resection of colonic cancer.

Laparoscopic parastomal hernia repair using a keyhole technique results in a high recurrence rate.

INTRODUCTION: Parastomal herniation is a common complication of stoma formation, and its operative treatment is notoriously difficult. Recently we have reported the promising short-term results of a keyhole technique in which a Gore-Tex Dual Mesh with a central keyhole is laparoscopically fashioned around the bowel to close the hernia. In the long-term, recurrence is one of the major issues in hernia repair, therefore, this aspect was prospectively investigated. METHODS: Since 2002, a total of 55 consecutive patients (27 men; median age, 63 years) with a symptomatic primary (n = 45) or recurrent parastomal hernia (n = 10) were electively operated using this technique. Patients were invited to the outpatient clinic on a regular basis and were examined for the occurrence of a recurrent hernia. At the last visit, all patients were asked to complete a short questionnaire. RESULTS: Median follow-up (98%) was 36 (range, 12-72) months. During follow-up a recurrent parastomal hernia was diagnosed in 20 patients (37%). Three recurrences were asymptomatic and were treated conservatively. The other 17 patients (85%) developed mild-to-severe symptoms necessitating redo-surgery in 9 (45%) patients. Surprisingly, satisfaction with the procedure was high among patients (89%), even in the presence of a recurrence. Patients who reported unsatisfactory results belonged mainly to the group in whom the initial laparoscopic approach had to be converted to an open procedure. CONCLUSIONS: Based on the results from the present study, which represents one of the largest patient series with the longest follow up available to date, it is concluded that laparoscopic parastomal hernia repair using a keyhole technique has an intolerably high recurrence rate with the currently available meshes. A new mesh with a less pliable central part and without the tendency to shrink is awaited.

The effects of adjuvant experimental radioimmunotherapy and hyperthermic intraperitoneal chemotherapy on intestinal and abdominal healing after cytoreductive surgery for peritoneal carcinomatosis in the rat.

BACKGROUND: Cytoreductive surgery (CS) followed by hyperthermic intraperitoneal chemotherapy (HIPEC) results in limited survival benefit and high morbidity and mortality rates in patients with peritoneal carcinomatosis (PC). Radioimmunotherapy (RIT) after CS of experimental PC has been shown to increase survival and compare favorably to HIPEC. The effects of RIT and HIPEC on wound healing after CS need to be determined. METHODS: PC was induced by intraperitoneal inoculation of CC-531 colon carcinoma cells in Wag/Rij rats. Animals were subjected to CS and anastomotic construction only or followed by RIT or HIPEC. RIT consisted of 74 MBq (177)lutetium-labeled anti-CC531 antibody MG1. HIPEC was performed by a closed abdominal perfusion technique using mitomycin-C during 60 minutes. Anastomotic and abdominal wall strength measurements were performed 3 and 5 days after surgery. RESULTS: At day 5, bursting pressure in ileum and colon anastomoses in the CS + HIPEC group, but not in the CS + RIT group, was lower (P < .01) than in the CS group. In the CS group, the colonic bursting site was more often outside the true anastomotic area (8 of 12 animals) than in the CS + HIPEC (1 of 12) and CS + RIT (5 of 12) groups. Abdominal wall strength in the CS + HIPEC group was significantly (P < .01) lower, at both measuring points, than that in both the CS group and the CS + RIT group. There was no difference between the latter. CONCLUSION: As adjuvant to CS, HIPEC showed a decrease in anastomotic and abdominal wall wound strength in a model of PC of CRC, whereas RIT did not.

Plasminogen activator, but not systemic antibiotic therapy, prevents abscess formation in an experimental model of secondary peritonitis.

BACKGROUND: Intra-abdominal abscesses are sources of recurrent or ongoing abdominal sepsis. They are an important target for prevention and treatment during or after surgical treatment of peritonitis. Experimental data suggest that fibrinolytic therapy may be effective when antibiotics are not. METHODS: Peritonitis was induced via intra-abdominal injection of a faeces and bacteria mixture in male Wistar rats. Surgical debridement was performed after 1 h. Next to untreated controls, animals were treated with antibiotics (ceftriaxone plus metronidazole), recombinant tissue plasminogen activator (rtPA) or both. Abdominal fluid samples were taken at 24, 72 and 120 h for interleukin 6, interleukin 10 and tumour necrosis factor alpha measurements and cell counts. After 5 days the abdomen was inspected for the presence of abscesses. RESULTS: Antibiotics did not significantly affect abscess formation. However, giving rtPA significantly reduced the number of rats with abscesses and the abscess load per rat, both in the absence and presence of concomitant antibiotic therapy. No adverse side-effects were observed and no meaningful differences in the local inflammatory response were found. CONCLUSION: In this rat model, rtPA consistently reduced abscess formation after surgical treatment of secondary peritonitis. It therefore represents a promising adjuvant to conventional therapy.

A comparison between radioimmunotherapy and hyperthermic intraperitoneal chemotherapy for the treatment of peritoneal carcinomatosis of colonic origin in rats.

BACKGROUND: Cytoreductive surgery (CS) followed by heated intraperitoneal chemotherapy (HIPEC) is considered the standard of care for the treatment of patients with peritoneal carcinomatosis (PC) of colorectal cancer (CRC). These surgical procedures result in a median survival of 2 years at the cost of considerable morbidity and mortality. In preclinical studies, radioimmunotherapy (RIT) improved survival after CS in a model of induced PC of colonic origin. In the present studies we aimed to compare the efficacy and toxicity of CS followed by adjuvant RIT in experimental PC to the standard of care, HIPEC. METHODS: PC was induced by intraperitoneal inoculation of CC-531 colon carcinoma cells in three groups of Wag/Rij rats. Treatment comprised CS only, CS + RIT or CS + HIPEC, immediately after surgery. RIT consisted of intraperitoneal administration of 74 MBq Lutetium-177 labeled MG1. HIPEC was performed by a closed abdomen perfusion technique using mitomycin C (16 mg/L during 60 minutes). The primary endpoint was survival. RESULTS: CS only or combined with RIT was well tolerated. Rats receiving CS + HIPEC were lethargic, suffered from diarrhea, and lost significantly more weight in the first postoperative week. Median survival of rats treated with CS + RIT was significantly longer than after CS alone (97 and 57 days, respectively, P < .004), whereas survival after CS + HIPEC or CS alone were not significantly different (76 and 57 days, respectively, P = .17). CONCLUSION: Survival after CS was significantly improved by RIT with Lutetium-177-MG1 in rats with PC of colorectal origin. Adjuvant HIPEC did not improve survival and was more toxic than adjuvant RIT.

Laparoscopic parastomal hernia repair is feasible and safe: early results of a prospective clinical study including 55 consecutive patients.

BACKGROUND: Parastomal herniation is a common complication, and its operative treatment is notoriously difficult. Recently, the authors have described a laparoscopic technique for closure and reinforcement of the hernia with a hand-made "funnel-shaped" Gore-Tex Dual Mesh. Potentially this technique combines the advantages of a mesh repair with those of minimal invasive surgery. METHODS: In 2002, a multicenter trial of this new technique was started in The Netherlands. To date, 55 consecutive patients (27 men; median age, 63 years) with a symptomatic primary (n = 45) or recurrent (n = 10) parastomal hernia have undergone elective surgery using this technique. The demographic, perioperative, and early follow-up data prospectively collected for these patients are presented in this report. RESULTS: Of the 55 procedures, 47 (85.5%) could be completed laparoscopically (median operation time, 120 min). Conversion to laparotomy was indicated because of dense adhesions prohibiting safe dissection (n = 4) or bowel injury (n = 4). No in-hospital mortality occurred. Postoperative recovery was uneventful for 47 patients (85%), who had a median hospital stay of 4 days. Surgical and nonsurgical complications occurred, respectively, for four patients each (7.2%). Full-thickness enterotomy appeared to be the most troublesome complication. After 6 weeks, when all the patients were reexamined, one recurrence was noted. CONCLUSION: Maximal efforts should be undertaken to prevent perioperative full-thickness enterotomy. Because this was achieved for the vast majority of patients, it is concluded that laparoscopic parastomal hernia repair is feasible and safe. Although a longer follow-up period is needed for definitive conclusions to be drawn regarding the recurrence rate, early follow-up evaluation shows very promising results.

The omentum-polypropylene sandwich technique: an attractive method to repair large abdominal-wall defects in the presence of contamination or infection.

BACKGROUND: Repair of abdominal wall defects in the presence of contamination or infection continues to be a significant problem for surgeons. The loss of tissue warrants reinforcement of the abdominal wall, preferably by autologous material. However, autologous repair often requires extensive operations that carry a high morbidity. Moreover, the lack of sufficient fascia may be so extensive that insertion of a prosthetic material is inevitable. Polypropylene (PP) is the most appropriate material to use under these circumstances, but without coverage, the mesh will wrinkle and ultimately be extruded. The present report describes an alternative technique for repair of heavily contaminated abdominal-wall defects. PATIENTS: Two patients with a very large heavily contaminated abdominal wall defect due to necrotizing fasciitis in one patient and a lion's bite in the other were treated with the omental sandwich technique. After radical debridement, resulting in a full thickness loss of the abdominal wall, the peritoneum was restored using absorbable polyglactin mesh. The fascial defect was bridged with a PP mesh that was fixed to the adjacent myoaponeurosis and covered with a pedicled omental flap. In both patients the omentum was covered with a split skin. RESULTS: Wound healing in both patients was without complications. Both patients had a sufficient abdominal wall, without signs of herniation after a follow up of 4 and 30 months, respectively. CONCLUSION: The omental sandwich technique is an attractive method to repair large abdominal wall defects in the presence of contamination or overt infection.

Surgical smoke and infection control.

Gaseous byproducts produced during electrocautery, laser surgery or the use of ultrasonic scalpels are usually referred to as 'surgical smoke'. This smoke, produced with or without a heating process, contains bio-aerosols with viable and non-viable cellular material that subsequently poses a risk of infection (human immunodeficiency virus, hepatitis B virus, human papillomavirus) and causes irritation to the lungs leading to acute and chronic inflammatory changes. Furthermore, cytotoxic, genotoxic and mutagenic effects have been demonstrated. The American Occupational Safety and Health Administration have estimated that 500000 workers are exposed to laser and electrosurgical smoke each year. The use of standard surgical masks alone does not provide adequate protection from surgical smoke. While higher quality filter masks and/or double masking may increase the filtration capability, a smoke evacuation device or filter placed near (2-5 cm) the electrocautery blade or on endoscope valves offers additional (and necessary) safety for operating personnel and patients.

Adhesion formation and reherniation differ between meshes used for abdominal wall reconstruction.

Incisional hernia is a common surgical problem, frequently requiring prosthetic mesh repair. The demands of the ideal mesh seem conflicting; ingrowth at the mesh-fascia interface, without development of adhesions at the visceral mesh surface. Various antiadhesives combined with macroporous mesh and composite meshes were studied for prevention of adhesions to mesh and ingrowth into the fascia. In 60 rats an abdominal wall defect was created and repaired with underlay mesh. Rats were divided into six groups and treated with polypropylene mesh (PPM, control), PPM with auto-cross-linked polymers (ACP) gel, PPM with fibrinogen glue (FG), polypropylene/expanded polytetrafluoroethylene (ePTFE) mesh, polypropylene/sodium hyaluronate/carboxymethylcellulose (HA/CMC) mesh, and polypropylene-collagen/polyethylene-glycol/glycerol (CPGG) mesh. Mesh infection was assessed in the postoperative period, adhesions and reherniations were scored at sacrifice 2 months after operation, and tensile strength of the mesh-tissue interface was measured. Six rats developed mesh infection, half of them were treated with PPM/ePTFE. The PPM/HA/CMC group showed a significant reduction in the amount and severity of adhesions. In animals treated with PPM/ACP and PPM/FG, severity of adhesions was reduced as well. Reherniation rate in the PPM/ACP group was 50% and significantly higher than that in other groups. Rats in the PPM/HA/CMC had the highest tensile strength. PPM/HA/CMC approaches the demands of the ideal mesh best, having superior antiadhesive properties, no reherniation and no infection in this rat model of incisional hernia.

Prophylactic mesh placement to prevent parastomal hernia, early results of a prospective multicentre randomized trial.

PURPOSE: Parastomal hernia (PSH) is a common complication after colostomy formation. Recent studies indicate that mesh implantation during formation of a colostomy might prevent a PSH. To determine if placement of a retromuscular mesh at the colostomy site is a feasible, safe and effective procedure in preventing a parastomal hernia, we performed a multicentre randomized controlled trial in 11 large teaching hospitals and three university centres in The Netherlands. METHODS: Augmentation of the abdominal wall with a retromuscular light-weight polypropylene mesh (Parietene Light™, Covidien) around the trephine was compared with traditional colostomy formation. Patients undergoing elective open formation of a permanent end-colostomy were eligible. 150 patients were randomized between 2010 and 2012. Primary endpoint of the PREVENT trial is the incidence of parastomal hernia. Secondary endpoints are morbidity, pain, quality of life, mortality and cost-effectiveness. This article focussed on the early results of the PREVENT trial and, therefore, operation time, postoperative morbidity, pain, and quality of life were measured. RESULTS: Outcomes represent results after 3 months of follow-up. A total of 150 patients were randomized. Mean operation time of the mesh group (N = 72) was significantly longer than in the control group (N = 78) (182.6 vs. 156.8 min; P = 0.018). Four (2.7 %) peristomal infections occurred of which one (1.4 %) in the mesh group. No infection of the mesh occurred. Most of the other infections were infections of the perineal wound, equally distributed over both groups. No statistical differences were discovered in stoma or mesh-related complications, fistula or stricture formation, pain, or quality of life. CONCLUSIONS: During open and elective formation of an end-colostomy, primary placement of a retromuscular light-weight polypropylene mesh for prevention of a parastomal hernia is a safe and feasible procedure. The PREVENT trial is registered at: http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=2018 .

Treatment of liver metastases, an update on the possibilities and results.

Long-term results after liver resection for colorectal liver metastases show 5-year survival rates between 35 and 40%. However, only a limited number of patients appear to be candidates for resection, far more patients prove to have unresectable disease. Present challenges in liver surgery for colorectal metastases are to improve patient selection, to increase the resectability rate and to improve survival by multimodality treatment approaches. The variables most consistently associated with a poor prognosis and tumour recurrence are tumour-positive resection margins and the presence of extra-hepatic disease. Hence, patient selection and preoperative staging should concentrate on accurate imaging of the liver lesions and the detection of extrahepatic disease. For liver imaging, spiral computed tomography (CT) scan or magnetic resonance imaging (MRI), supplemented by intra-operative ultrasound, are currently regarded as the best methods for evaluating the anatomy and resectability of colorectal liver metastases. Extrahepatic disease should be investigated by spiral CT of the chest and abdomen and when possible by 2-fluouro-2-deoxy-D-glucose-positron emission tomography (FDG-PET). Resection remains the gold standard for the surgical treatment of colorectal liver metastases. In experienced centres, resection is a safe procedure and mortality rates are below 5%. The aim of resection should be to obtain tumour-negative resection margins. Edge cryosurgery should be considered in cases where very close resection margins are anticipated. The role of adjuvant chemotherapy after resection is still controversial, although two recent studies show a clear benefit. For the moment, local tumour ablative therapies such as cryotherapy and radiofrequency therapy should be considered as an adjunct to hepatic resection in those cases in which resection can not deal with all of the tumour lesions. In these cases, there seems a beneficial effect of a combined treatment consisting of resection and local tumour ablation. At this stage, there are no randomised data that local tumour ablation is as effective as resection. For a selected group of patients with unresectable liver metastases, there may be a chance to turn unresectable disease to resectable disease by aggressive neo-adjuvant chemotherapy or portal vein embolisation. For patients with unresectable disease, many different chemotherapy schedules may be used based on systemic drug administration. Regional chemotherapy and isolated liver perfusion should only be used within a study design.

Unexplained rising carcinoembryonic antigen (CEA) in the postoperative surveillance of colorectal cancer: the utility of positron emission tomography (PET).

The aim of the study was to evaluate the use of positron emission tomography with [18F]-fluorodeoxyglucose (FDG-PET) in patients with unexplained rising carcinoembryonic antigen (CEA) in the postoperative surveillance of colorectal cancer. 50 consecutive patients with elevated CEA levels and a completely normal (n=31) or equivocal (n=19) conventional diagnostic work-up (CDW) were retrospectively selected. All PET images were reviewed with full knowledge of the CDW. The gold standard consisted of histology, or clinical follow-up of more than 1 year. Recurrent disease was established in 56 lesions in 43 patients. On a patient-based analysis, the sensitivity of FDG-PET was 34/43 (79%), and the positive predictive value 34/38 (89%). In 14/50 patients (28%), the FDG-PET findings led to a surgical resection with curative intent. On a lesion-based analysis, FDG-PET detected 42/56 lesions (sensitivity: 75%), the positive predictive value was 79% (42/53). These results demonstrate that FDG-PET can have a clear impact on patient management in patients with an unexplained elevation in CEA levels.