Selective internal radiation therapy (SIRT): a new modality for treating patients with colorectal liver metastases

BACKGROUND

Selective internal radiation therapy (SIRT) is a new and developing modality for treating non-resectable liver tumours. Evidence is emerging that it is very efficacious in patients with hepatocellular cancer and colorectal liver metastases.

DISCUSSION

SIRT generally involves a single delivery of (90)yttrium micro-spheres into the hepatic artery. Preferential uptake is achieved into liver tumours, because of their predominant hepatic arterial blood supply. Average tumour doses of radiation in excess of 200 Gy are achieved. The treatment is generally well tolerated and has been documented by a number of groups internationally to achieve response rates of around 90% in patients with extensive colorectal cancer (CRC) liver metastases. Since the product obtained FDA approval in the USA in 2002, it is being more widely employed and investigated. Unlike other ablative therapies being applied to non-resectable liver tumours, SIRT is indicated even in patients with an extensive burden of liver tumour. Indications, dosing schedules and expected outcomes will become better defined as more groups take up the treatment.

Common presence of Helicobacter DNA in the gallbladder of patients with gallstone diseases and controls

BACKGROUND

Several species of Helicobacter colonise the biliary tract of animals and cause hepatobiliary diseases. Helicobacter species have also been identified in the gallbladder of a high proportion of Chilean patients with gallbladder cancer.

AIM

To determine the presence of Helicobacter species, particularly Helicobacter pylori and Helicobacter bilis, in the gallbladder of patients with non-malignant gallbladder diseases and control patients.

PATIENTS AND METHODS

DNA was extracted from gallbladder samples from 122 consecutive patients undergoing cholecystectomy. The presence of Helicobacter genus-specific or Helicobacter pylori and Helicobacter bilis species-specific DNA was determined by polymerase chain reaction and sequence analysis. The presence of Helicobacter pylori-specific immunoglobulin G in the serum (n=84) and bile (n=104) samples was determined by enzyme linked immunosorbent assay.

RESULTS

Helicobacter DNA was detected in 61 (50.0%) gallbladder samples: 29 of 60 (48.3%) patients with symptomatic gallstone, six of 10 (60.0%) patients with asymptomatic gallstones, 11 of 15 (73.3%) patients with other biliary diseases, and 15 of 37 (40.5%) control patients, respectively. Among them, 39 samples were positive for Helicobacter pylori but none were positive for Helicobacter bilis. Sequence analysis of Helicobacter genus-positive samples showed that 56 samples were Helicobacter pylori and five were Helicobacter species 'Liver 3' strain. Overall, there was no significant difference in the detection rate of Helicobacter DNA or the levels of serum and bile Helicobacter pylori-specific immunoglobulin G in the various biliary disease groups compared with control patients. Neither was there any significant difference in the blood biochemistry and liver function tests between patients with positive and negative Helicobacter DNA detection.

CONCLUSION

Helicobacter species' DNA are commonly present in the gallbladder of patients with gallstone diseases and in controls, implying that Helicobacter infection alone may not play a significant role in the formation of gallstones. However, our results do not exclude the possibility of Helicobacter infection as a cofactor in the development of gallstones.

Selective internal radiation therapy with 90yttrium microspheres for extensive colorectal liver metastases

Increasing attention has been given to treatments for colorectal liver metastases ever since hepatic resection was established as being worthwhile. Given the high proportion of patients who die of colorectal cancer with liver-only disease, it seems appropriate to be developing and investigating methods of local liver tumor ablation. Selective internal radiation therapy (SIRT) is a relatively new, not widely used, modality suitable for use even in patients with extensive liver involvement. Fifty patients with advanced, nonresectable, colorectal liver metastases were treated with SIRT between February 1997 and June 1999. Estimated liver involvement was less than 25% in 30 patients, 25% to 50% in 13, and greater than 50% in seven. A single dose of between 2.0 and 3.0 GBq of 90yttrium microspheres was injected into the hepatic artery via a subcutaneous port and followed at 4-week intervals by regional chemotherapy with 5-fluorouracil. SIRT was well tolerated with no treatment-related mortality, although some treatment-related morbidity did occur including a 12% incidence of duodenal ulceration. Responses to SIRT were assessed by serial carcinoembryonic antigen (CEA) measurements and CT scans. Median CEA values 1 and 2 months after SIRT (expressed as percentage of initial CEA) were 19 and 13, respectively. Patients were assigned to one of two groups based on whether or not extrahepatic disease (EHD) developed within 6 months of SIRT. Median survival from SIRT for group 1 (EHD) (n = 26) was 6.9 months (range 1.3 to 18.8 months) and estimated survival +/- standard error at 6, 12, and 18 months was 57.7 +/- 3.8%, 23.1 +/- 4.8%, and 0%, respectively. For group 2 (no EHD) (n = 24), median survival was 17.5 months (range 1.0 to 30.3 months) with estimated survival at 6, 12, 18, 24, and 30 months of 79.2 +/- 2.9%, 66.7 +/- 3.6%, 55.9 +/- 3.3%, 25.2 +/- 4.4%, and 16.8 +/- 5.0%, respectively. This difference is statistically significant by log-rank test (P < 0.010). SIRT is a highly effective and well-tolerated regional treatment for extensive colorectal liver metastases. Tumor marker data suggest that substantial destruction of liver tumors can be achieved in more than 90% of patients by a single treatment. Survival times, particularly for those who do not develop extrahepatic metastases for some time, appear to be extended. SIRT warrants further use and investigation in patients with advanced colorectal liver metastases.

Serum proinflammatory cytokine response in patients with advanced liver tumors following selective internal radiation therapy (SIRT) with (90)Yttrium microspheres

PURPOSE

To determine the changes in serum levels of proinflammatory cytokines within 48 h after selective internal radiation treatment (SIRT) in patients with advanced liver cancers.

METHODS AND MATERIALS

Twenty-eight patients with advanced liver cancers who underwent SIRT were recruited into the study. Serum levels of interleukin (IL)-1beta, IL-6, IL-8, IL-10, IL-12, tumor necrosis factor-alpha, and interferon-gamma were determined prior to and 3, 6, 12, 24, and 48 h after SIRT. Their changes were correlated to adverse reactions following treatment as assessed by constitutional symptom scores, and routine blood and liver function tests at 24 and 48 h post-SIRT and falls in serum carcinoembryonic antigen (CEA) level 1 month post-SIRT.

RESULTS

Serum IL-6 levels were significantly increased at 24 (p < or = 0.05) and 48 h (p < or = 0.01) post-SIRT. In contrast, there was no significant change in the serum levels of other cytokines studied. The increase in serum IL-6 at 24 h post-SIRT was significantly correlated with the changes in serum alanine transferase (p < or = 0.05) and C-reactive protein (p < or = 0.001) levels and total leukocyte counts (p < or = 0.001) at both 24 and 48 h post-SIRT. Changes in serum IL-6 level were also significantly correlated to the rise of serum aspartate transaminase levels at 48 h post-SIRT (p < or = 0.001), but not with the scores of constitutional symptoms or the changes of serum CEA at 1 month post-SIRT.

CONCLUSION

Absence of significant changes in most of proinflammatory cytokines studied confirmed that SIRT is a reasonably safe and well-tolerated treatment with minimal side-effect from the point of view of cytokine-related inflammation. The correlation of serum IL-6 changes with several liver enzymes and C-reactive protein but not with clinical symptom scores or serum CEA levels suggests that the rise in IL-6 levels in the first 48 h following SIRT most likely reflect normal liver cell damage rather than tumor cell damage.

Selective internal radiation therapy (SIRT) with 90Yttrium microspheres for extensive colorectal liver metastases

BACKGROUND/AIMS

SIRT (selective internal radiation therapy) is a new modality for the treatment of nonresectable liver tumors which has been reported to achieve high response rates. We report our initial experience in patients with extensive colorectal liver metastases.

METHODOLOGY

Thirty-eight (38) patients were treated with SIRT between February 1997 and November 1998. Liver involvement was < 25% in 19 patients, 25-50% in 9 and > 50% in 10. Patients received 90Yttrium microspheres into the hepatic artery via an arterial port and subsequent 4-weekly cycles of hepatic artery chemotherapy with 5-fluorouracil.

RESULTS

SIRT was well tolerated and no treatment-related mortality was observed. Responses to SIRT as indicated by falling tumor markers and serial 3-monthly computed tomography scans were seen in over 90% of patients. Estimated survival at 6, 12 and 18 months was 70%, 46% and 46%, respectively, and was principally determined by the development of extrahepatic metastases.

CONCLUSIONS

SIRT is well tolerated in patients with extensive colorectal liver metastases and achieves encouraging liver tumor responses, which are well maintained by hepatic artery chemotherapy. The modality warrants wider use and investigation.

Development of a dendritic cell (DC)-based vaccine for patients with advanced colorectal cancer

BACKGROUND/AIMS

An ability to induce a specific immune response to cancer would provide an important new dimension in its management. We report our initial work investigating the safety and efficacy of a dendritic cell vaccine in patients with colorectal cancer.

METHODOLOGY

Fifteen (15) patients with advanced colorectal cancer had vaccines prepared from autologous dendritic cells pulsed with tumor RNA and keyhole limpet hemocyanin. Vaccines were administered intravenously and patients were observed in hospital for 2 days. Thereafter, consultations were at monthly intervals at which time booster doses were given to a total of 4. Patients were monitored with weekly blood tests, including carcinoembryonic antigen, and 3-monthly computed tomography scans.

RESULTS

Flow cytometry confirmed dendritic cell phenotype and in vitro function was confirmed by mixed lymphocyte reaction. No major adverse effects were observed. Eleven of 13 patients tested developed a positive keyhole limpet hemocyanin skin test and in 7 the carcinoembryonic antigen fell suggesting some in vivo anticancer effect. To date no dramatic clinical responses have been observed but follow-up is very short.

CONCLUSIONS

The therapy was well tolerated. Dendritic cells were verified by phenotype and in vitro function. The positive keyhole limpet hemocyanin skin test confirms in vivo function by effective vaccination to keyhole limpet hemocyanin. Demonstration of any anticancer efficacy will require further follow-up.

Improvement in co-morbidities following weight loss from gastric bypass surgery

BACKGROUND

Clinical observation reveals a close association between morbid obesity and a variety of serious medical conditions. This report describes the changes observed in some of these co-morbid conditions, following weight loss achieved by silastic ring gastric bypass (SRGBP).

METHODS

Between 1990 and 1998, 157 severely obese patients aged 15-62 years underwent SRGBP. Initial and follow-up data was recorded prospectively on a computerized database, with minor subsequent additions being achieved by phone call or questionnaire. Particular attention was given to associated co-morbidities and improvement in these that occurred during follow-up. Median pre-operative BMI was 45 (33-97). Patients were followed for a median 2.5 years. At 2 years post-SRGBP, median BMI was 28 (20-52). Weight loss was statistically significant (p<0.0001).

RESULTS

Before surgery 42 patients were being treated for hypertension and 34 for asthma. Withdrawal of all medication for these conditions was achieved sometime after surgery in 18 and 17 patients respectively. NIDDM was present in 19 patients before surgery and subsequently resolved completely in 18. Eleven of the 12 patients with recognized obstructive sleep apnea before surgery had resolution of this after surgery. Dyslipidemia was present in the majority of patients before surgery and resolved or improved following surgery in almost all instances.

CONCLUSIONS

The findings indicate that reliable and substantial weight loss can be accomplished by gastric bypass surgery with accompanying major reductions in associated co-morbidities. Such benefits suggest that greater attention should be given to this form of treatment for those with severe obesity.

Hepatic artery access ports: recognizing and avoiding the problems

BACKGROUND

Regional approaches to the management of hepatic tumours are appropriate in some clinical situations and include hepatic arterial chemotherapy (HAC) and selective internal radiation therapy (SIRT). Both require access to the hepatic artery, which is conveniently achieved with a subcutaneously placed port. Placement and use of these ports may be associated with a variety of technical problems which can impact adversely on the outcome of the treatment. The present paper outlines the problems related to port usage for regional hepatic therapies, with emphasis on the technical aspects of insertion and interpretation and management of subsequent problems.

METHODS

Hepatic artery port placement was attempted in 129 patients for use with either SIRT and/or HAC. Ports were used or flushed at monthly intervals.

RESULTS

Successful port insertion was achieved in 127 patients, of whom 87 received HAC alone, seven received SIRT alone, 28 patients received both and in five patients the port was never used. Methylene blue injection was used to identify anomalous arterial anatomy, which was found in 26 of 95 patients (27%), and significant extrahepatic 'access', which was seen in 25 patients (26%) after initial placement. Forty-six instances of technical problems preventing continued use of the port occurred in 43 patients after a median of 4 (0-36) cycles of chemotherapy, including hepatic artery thrombosis (n = 26), catheter blockage (n = 4), duodenal fistula (n = 3), gastrointestinal (GI) bleeding (n = 3), side-effects (n = 3), access problems (n = 3), extravasation (n = 3) and infection (n = 1).

CONCLUSION

Methods used to identify, manage and in some instances prevent the occurrence of these problems are discussed.

Dendritic cell-based cancer immunotherapy: potential for treatment of colorectal cancer?

Human tumours including those of the gastrointestinal tract express a number of specific antigens that can be recognized by T cells, thus providing potential targets for cancer immunotherapy. Dendritic cells (DC) are rare leucocytes that are uniquely potent in their ability to capture, process and present antigens to T cells, and so selectively migrate through tissues to reach lymph nodes and spleen where initiation of immune responses takes place. Studies in murine tumour models have shown clearly that DC are capable of presenting tumour antigens to initiate tumour-specific cytotoxic T cell responses, and DC vaccination can induce anti-tumour activity against both primary tumours and pre-established tumour metastases. These findings together with the ability to culture sufficient numbers of DC from human bone marrow or blood progenitors have prompted the current major interest in their potential use in human tumour vaccination. Vaccine production involves harvesting autologous DC from cultured peripheral blood mononuclear cells in the presence of a cocktail of cytokines, ex vivo exposure of the DC to tumour antigens and return of pulsed DC to the patient to induce tumour immunity. Reports from Phase I/II clinical trials indicate that DC vaccines are safe with little or no side effect, and are capable of initiating antigen-specific T cell responses. Furthermore, defined tumour antigens are not necessarily required, which may make the process more applicable to human cancers, including many gastrointestinal cancers that lack well-characterized tumour-specific antigens. Additional trials of DC vaccination for a variety of human cancers including colorectal cancers are under way, and refinement of vaccine protocols and methods for targeting tumour antigens to DC in vivo are also being explored. There is reason to believe that DC-based vaccination could become an adjunct to current treatments for human cancers including colorectal cancer in the foreseeable future.

Acalculous gallbladder pain: a largely unrecognised entity

AIM

To study the presentation for and outcome of cholecystectomy in patients with acalculous gallbladder pain.

METHODS

Sixty-six consecutive patients with prospective documentation underwent cholecystectomy for putative acalculous gallbladder pain between December 1988 to April 1995. The diagnosis was made on clinical grounds, but in the majority, a CCK oral cholecystogram was performed. Outcomes were assessed by postal questionnaire mailed in October 1995 or by the last recorded follow- up.

RESULTS

Fifty-eight females and eight males, with a median age of 37.5 years had experienced abdominal pain, usually with associated nausea, for a median of three years. Preoperative investigations were non-contributory, with the exception of the CCK oral cholecystogram which was regarded as abnormal in all instances. At a median follow-up of 40 months, 48 patients (72.7%) described their symptoms as either totally relieved or much improved by cholecystectomy.

CONCLUSION

Though the pathophysiology remains poorly understood, there is clearly a group of patients who suffer from gallbladder pain in the absence of gallstones and who benefit from cholecystectomy.

Hydatid disease in New Zealand. What remains and how should we treat it?

AIM

The incidence of hydatid disease in New Zealand has steadily declined since the introduction of control measures in the early 1960s. However, patients continue to present for management of newly recognised, disseminated or recurrent disease. It is desirable that doctors in New Zealand have some knowledge of current patterns of presentation and management of the disease.

METHODS

Twenty-five patients with hydatid disease have been seen and managed over a ten-year period by one hepato-biliary surgeon. Their presentation and management is outlined and discussed. Surgery, after pre-treatment with albendazole, was undertaken in 15 patients where eradication seemed possible and desirable and in three others presenting with complications (infection, rupture, fistulation). Albendazole treatment alone was used in six patients (five with uncomplicated recurrent or disseminated disease) and one patient has simply been observed.

RESULTS

There were no deaths in 18 patients who underwent surgery and no recurrent disease has been found. Major morbidity was confined to those having surgery for complications. All six patients who received albenzadole alone had a good clinical and radiological response, though they required follow-up.

CONCLUSIONS

It is suggested that surgery (with albendazole pre-treatment) should be reserved for those with either curable disease or complications and that all others should be managed, in the first instance, by albendazole alone. Providing treatment is instituted before complications develop it should be associated with minimal morbidity.

Hepatic cryotherapy and subsequent hepatic arterial chemotherapy for colorectal metastases to the liver

This paper presents an experience of thirty consecutive patients with hepatic colorectal metastases who were treated with hepatic cryotherapy and subsequent hepatic arterial infusion (HAI) chemotherapy using 5 FU. Patients with colorectal metastases confined to the liver but not suitable for resection, and with liver involvement of less than 50% were offered the treatment. Prospective documentation of all patients was undertaken with data being recorded on a computerised database. Patients had a median of 6 (2-15) lesions with sizes ranging from 1-12 cm. There was no 30 day mortality. Postoperative complications developed in 8 patients but were followed by full recovery in all instances. Side effects from chemotherapy occurred in 23% of cycles. Twenty seven patients have died. Median survival from the time of cryotherapy was 18.2 months (7-34), or 23 months (9-44) from diagnosis of liver lesions. Hepatic cryotherapy with subsequent arterial chemotherapy is safe and well tolerated. The results suggest survival of patients with colorectal hepatic metastases can be improved by the use of this modality of treatment.

Silastic ring gastric bypass: a comparison of two ring sizes: a preliminary report

BACKGROUND

The silastic ring (vertical) gastric bypass (SRGB) was introduced by Fobi in 1989, in an effort to combine the advantages of the Roux-en-Y gastric bypass with those of the VBG, while avoiding disadvantages of each. We remain unsure of the ideal ring size.

METHODS

Sixty-four patients having SRGB between June 1990 and September 1994 had a 5.5 cm ring placed and 24 patients operated between October 1994 and September 1995 had a 6.0 cm ring placed. Weight loss and quality of eating data is compared 12 months after surgery.

RESULTS

Median preoperative per cent excess weight was 113 (range 76-209) in the 5.5 cm group and 106 (range 79-196) in the 6.0 cm group. Weight loss was equivalent at 12 months, with median percent excess weight of 33 (range 8-109) and 27 (range 6-81) in the two groups respectively. Quality of eating data appears better in those with the larger ring size. Nine patients with a 5.5 cm ring have subsequently had their ring removed to improve their quality of eating and a further six may require this in the future. One patient with a 6.0 cm ring has had the ring removed and two others may require this be done.

CONCLUSION

An SRGB with a 6.0 cm ring achieves equivalent weight loss to one with a 5.5 cm ring, but with better quality of eating, and less prospect of requiring ring removal. However, there remains a small proportion of patients in whom a 6.0 cm ring is poorly tolerated. For this reason a 6.5 cm ring should be tested.

Silastic ring gastric bypass: results in 64 patients

BACKGROUND

The silastic ring gastric bypass (SRGB) was introduced by Fobi in 1989, in an effort to combine the advantages of the Roux-en-Y gastric bypass with those of the vertical banded gastroplasty, while avoiding the disadvantages of each.

METHODS

The results of our first 64 patients who underwent SRGB with a 5.5 cm ring have been reviewed with particular attention to weight loss, short- and medium-term morbidity and patient satisfaction. Most patients have had regular follow-up, and those not seen during the last 6 months were sent a postal questionnaire.

RESULTS

The patients included 52 females and 12 males, ranging in age from 23 to 59 years (median age=39 years) at the time of surgery. Median preoperative weight, body mass index (BMI) and % excess weight were 126 kg (range 89-253 kg), 44 kg/m2 (range 36-78 kg/m2) and 113 (range 76-209) respectively. There were no serious postoperative complications and no deaths. Median hospital stay was 7 days (range 5-14 days). Eight patients (13%) are known to have had a staple-line dihiscence. Eighteen patients (28%) have had major difficulties with eating, and in nine (14%) of these the silastic ring has been removed with resolution of the eating problems, but some gain in weight. In the 54 patients with follow-up data at 2 years, median weight was 78 kg (range 55-137 kg), median BMI was 27 kg/m2 (range 20-43 kg/m2) and mean +/- SD % excess weight loss was 69+/-16. After 2 years of follow-up, eight of 54 patients (15%) were unhappy with the results of the procedure.

CONCLUSION

SRGB is an effective, safe and well-tolerated procedure for achieving weight loss in the morbidly obese. The principal drawbacks relate to staple-line problems and eating difficulties related to the silastic ring. A 5.5 cm ring is probably too small to be ideal.

Peritoneovenous shunting for malignant ascites

AIM

Malignant ascites may produce a cluster of symptoms including abdominal distension, early satiety, respiratory embarrassment, impaired mobility and lethargy. Successful relief of these symptoms is often difficult to attain. We report on the use of peritoneovenous shunting in a group of patients with troublesome malignant ascites with particular reference to the effectiveness and complications of the procedure.

METHODS

Twenty one Denver peritoneovenous shunts were placed in 19 patients with malignant ascites. The patients included 16 females and three males and had a median age of 54 years. All had previously been treated with vigorous diuretic therapy and/or repeated paracentesis. Shunt insertion was carried out under general anaesthetic in a manner similar to that described by others.

RESULTS

The procedure was well tolerated by most patients. Median hospital stay was 6 days. One patient died 11 days after her surgery from what was thought to be an unrelated cause. Another patient suffered major problems after shunt insertion from exacerbation of pre-existing pleural effusions. All other complications were minor and self limiting. Two shunts failed to function within the first week. Excellent shunt function with resolution of ascite and of associated symptoms was seen in 16 patients. In five late shunt occlusion occurred with resulting reaccummulation of ascites but in four of these shunt function was able to be restored. Median survival in the 18 patients who survived the procedure was 5.5 months and in 14 of these the shunt was functioning at the time of death with good control of ascites.

CONCLUSION

Malignant ascites can result in very troublesome symptoms for patients who may otherwise have some time to live. Peritoneovenous shunting is a well tolerated relatively minor surgical procedure which can achieve excellent control of ascites in the majority of such patients.

Percutaneous biopsy of operable liver lesions: is it necessary or advisable?

AIM

The necessity and desirability of performing percutaneous biopsy of potentially resectable liver tumours is called into question.

METHODS

Two cases are reported in which percutaneous biopsy of resectable liver tumours was performed unnecessarily and resulted in needle track seeding.

RESULTS

In both instances patients who underwent potentially curative liver resection were rendered incurable because of biopsy track recurrence.

CONCLUSION

The common practice of performing percutaneous ultrasound or CT guided biopsy of potentially resectable lesions in the liver is generally neither necessary nor desirable.

Inhibition of the stimulated canine exocrine pancreas by amino acids and fat

To investigate the possible exocrine pancreatic inhibitory actions of amino acids and fat, pancreatic fistula outputs and plasma concentrations of glucagon, somatostatin, and pancreatic polypeptide were measured for response to intravenous (IV) and intraduodenal nutrient administration in six dogs submaximally stimulated with cholecystokinin. Intravenous amino acids caused abrupt and significant 45% to 73% reductions in stimulated pancreatic protein, bicarbonate, and volume outputs. There were no significant associated changes in plasma hormone concentrations and no similar immediate pancreatic inhibition with IV mannitol, thus suggesting a possible direct inhibitory effect of amino acids. Intraduodenal amino acids and IV fat evoked no significant pancreatic output suppression. Intraduodenal fat rapidly caused a significant 40% to 62% reductions in stimulated outputs that were associated with an 81% rise in plasma pancreatic polypeptide concentration, suggesting a gut-mediated inhibition. We conclude that IV amino acids and intraduodenal fat both inhibited stimulated pancreatic secretion but probably by different mechanisms.

Papillary cystadenocarcinoma of the appendiceal stump with mucocele and peritoneal metastases

A 54-year-old Polynesian male developed a mucocele of the appendiceal stump 25 years after appendicectomy. Scattered peritoneal deposits up to 0.4 cm in diameter were also identified at laparotomy, and these were confined to the right iliac fossa. The cyst was excised with a right hemicolectomy and histology showed a mucus-producing papillary cystadenocarcinoma arising in the unburied appendiceal stump. There was invasion of the cyst wall and the peritoneal nodules contained metastatic tumour acini. The patient is well 12 months after surgery. This is a case of a rare tumour arising uniquely in an appendiceal stump and producing a mucocele. The term mucocele is discussed and recommendations made for its usage in pathological diagnosis.

Choledochal cyst: case reports and current concepts

Choledochal cyst is an unusual but serious condition which most commonly affects Oriental people. Recent experience of three patients with this condition in whom diagnosis was made by ultrasound examination is reported. Cholangiography (ERCP or PTC) was performed in two of the cases to define the anatomy. All three cases were successfully managed by cyst excision and biliary reconstruction by Roux-en-Y hepaticojejunostomy. The rationale for and importance of cyst excision are discussed.

Pressure changes in canine gall-bladder associated with emptying

1. For decades it has been supposed that emptying of the gall-bladder follows a rise in gall-bladder pressure of some 10-15 mmHg and relaxation of the sphincter of Oddi. 2. This subject has been re-examined in dogs chronically fitted with fistulas, using a model which does not entail interference with either the bile duct or sphincter of Oddi. 3. The pressure in the gall-bladder was recorded continuously under fasting conditions, after feeding and after intravenous infusion of the octapeptide of cholecystokinin (CCK-OP) in six dogs. 4. Gall-bladder pressure showed a modest sustained rise of 2-3 mmHg following ingestion of food and intravenous infusions of CCK-OP (125 ng kg-1 h-1). 5. During half of the experiments a transient rise of 3-10 mmHg lasting 2-3 min was observed after feeding and following infusion of I.V. CCK-OP (125 ng kg-1 h-1). Emptying of the gall-bladder, measured by bilirubin output from the biliary fistula, started shortly before the peak rise in pressure occurred. 6. We conclude that a significant rise in gall-bladder pressure is not a prerequisite for emptying and that the pressure changes occurring physiologically are smaller than have been reported previously. 7. We believe that the larger pressure changes recorded in the past may have been produced because of resistance to bile flow introduced by the models employed. 8. Emptying of the gall-bladder, in the dog, appears to have occurred within 40 min of the ingestion of food, suggesting that the cephalic and gastric phases of this process are quantitatively more important than has been thought previously.

Faecal carcinoembryonic antigen (CEA) in patients with large bowel cancer

The possibility that faecal CEA may be a more useful measurement than serum CEA for the detection of large bowel cancer has received very little attention. For this reason faecal CEA was measured before and after tumour resection in colorectal cancer patients and in a variety of control subjects. CEA was extracted from faeces by a new method with 3M KCl and assayed by an EIA technique utilising two monoclonal antibodies. Mean +/- SE faecal CEA in 32 cancer patients was 4.15 +/- 1.17 micrograms/g preoperatively. Values were not related to either stage of disease or serum CEA and they fell to 0.83 +/- 0.34 micrograms/g (n = 20) following tumour resection (P less than 0.05). Mean +/- SE faecal CEA in 34 control patients with no known colorectal disease was 0.94 +/- 0.49 micrograms/g which was significantly lower than in the cancer patients (P less than 0.05). Furthermore faecal CEA in 25 patients with non malignant colorectal disease was 1.44 +/- 0.63 micrograms/g which again was significantly lower than that in the cancer patients. It is concluded that as CEA is present in the faeces of the majority of colorectal cancer patients even at early stages of the disease its measurement here may be more useful for the detection of large bowel cancer than that in serum.

Single dose mezlocillin versus three dose cefuroxime plus metronidazole for the prophylaxis of wound infection after large bowel surgery

A prospective, randomized, controlled trial was conducted in 116 consecutive patients undergoing colorectal surgery to compare single dose prophylaxis with mezlocillin to cefuroxime plus metronidazole in three doses. Patients were randomized to receive either a single dose of iv mezlocillin (5.0 g) or three doses of iv cefuroxime plus metronidazole at 8-hourly intervals. The first dose was given on the operating table. The overall wound infection rate in the mezlocillin treated patients (n = 54) was 30% and in the patients treated with cefuroxime plus metronidazole (n = 56) 25%. This difference is not statistically significant. When trivial wound infections were disregarded the wound infection rates were 11% and 16% respectively, which again was not statistically significant.

Faecal carcinoembryonic antigen in colorectal cancer patients

Carcinoembryonic antigen (CEA) has been measured in the faeces of large bowel cancer patients and control subjects to determine whether this measurement might be a useful aid in the diagnosis of large bowel cancer. The mean faecal CEA in 24 cancer patients fell significantly from 10.43 +/- 2.39 micrograms/g pre-operatively to 3.61 +/- 0.72 micrograms/g postoperatively (p less than 0.05). Pre-operative values were not related to either tumour stage or serum CEA. In 20 patients with no known colorectal disease the mean faecal CEA was 5.43 +/- 1.95 micrograms/g which was significantly lower than the mean pre-operative value in the cancer patients (p less than 0.05). In 14 patients with a variety of benign colonic diseases the mean faecal CEA was 7.12 +/- 1.39 micrograms/g which was not significantly different from the mean pre-operative value in the cancer patients. Considerable overlap of values was observed between individual cancer and control patients making the test, as presently carried out, non-discriminatory. If the potential for making the test more cancer specific can be realised, however, faecal CEA determination may permit discrimination between cancer and non-cancer patients at a relatively early stage of disease.

Symptom duration and pathologic staging of colorectal cancer

A large proportion of patients with colorectal cancer continue to present with relatively advanced and therefore incurable tumours. While delay in diagnosis is often felt to have been a contributing factor, the validity of this has seldom been questioned. Two hundred and eleven consecutive large bowel cancer patients have been prospectively studied with respect to their duration of symptoms and pathologic stage: 7.1% presented with Dukes A tumours and a mean symptom duration of 11.2 months; 38.9% with Dukes B tumours and a mean symptom duration of 4.9 months; 22.3% with Dukes C1 tumours and a mean symptom duration of 5.3 months; 3.8% with Dukes C2 tumours and a mean symptom duration of 3.9 months and 26% with stage D disease and a mean symptom duration of 3.8 months. There was no tendency for a longer symptomatic period in patients with more advanced disease. Indeed the Dukes A patients had a significantly longer duration of symptoms than those with all other stages of disease. It is argued that diagnosis at a more favourable pathologic stage would only be possible by presymptomatic tumour detection.

Role of cholecystokinin in pancreatic exocrine response to intraluminal amino acids and fat

Controversy continues over the relative contributions made by hormonal and neural mechanisms in the exocrine pancreatic response to ingested food. The recent description of the drug proglumide as a specific, competitive cholecystokinin (CCK)/gastrin receptor antagonist has permitted reevaluation of the role of CCK in this process. In chronic pancreatic fistula dogs, dose-response studies were performed to determine the effect of proglumide on the pancreatic responses to octapeptide of CCK (CCK-OP), intravenous bethanechol, intraduodenal amino acids, and intraduodenal fat. Pancreatic volume, protein, and bicarbonate outputs to all doses of CCK-OP were inhibited significantly (P less than 0.05) in a competitive manner, consistent with the proposed mode of action of proglumide. In contrast, proglumide caused only minor and insignificant inhibition of the output responses to intravenous bethanechol. Virtually complete inhibition to all doses of intraduodenal amino acids and fat was observed with proglumide administration. If indeed proglumide is a specific CCK receptor antagonist, these results support the hypothesis that CCK is the major mediator of the intestinal phase of exocrine pancreatic secretion.

Pancreatic secretory responses to intravenous hyperalimentation and intraduodenal elemental and full liquid diets

Intravenous hyperalimentation and enteral elemental diets have both been advocated for the nutritional support of patients with acute pancreatitis, pancreatic fistula, and proximal small bowel fistula. The exocrine pancreatic responses to these nutrients compared to one another and to full liquid diet have been inadequately studied. Therefore, pancreatic protein, volume, and bicarbonate responses to graded doses of (1) intravenous hyperalimentation, (2) intraduodenal elemental diet, and (3) intraduodenal full liquid diet were compared in duplicate experiments in five dogs with chronic pancreatic fistulas. Both intraduodenal elemental and full liquid diets caused comparable and significant dose-related increases in pancreatic protein, volume, and bicarbonate outputs over basal levels (p less than 0.05). In contrast, there was no stimulation of pancreatic secretion by intravenous hyperalimentation. It therefore appears that of the methods studied, only intravenous hyperalimentation can provide full nutritional support while maintaining the pancreas at rest.

Inhibition of the stimulated exocrine pancreas by absorbed amino acids

Intravenous infusion of amino acids is known to inhibit the stimulated pancreas and it has been suggested that this may act as a feedback mechanism in pancreatic regulation. To investigate this, chronic pancreatic fistula dogs were studied to determine if postprandial levels of hyperaminoacidemia inhibit the stimulated pancreas. Duplicate dose-response experiments using exogenous cholecystokinin (CCK) and intraduodenal amino acids were performed with and without a simultaneous intravenous infusion of mixed amino acids, which simulated postprandial hyperaminoacidemia. Significant (P less than 0.05), though minor, inhibition of pancreatic responses to both endogenous and exogenous CCK was noted with the simultaneous infusion of amino acids. It was concluded that, while amino acids may exert some inhibitory influence on pancreatic secretion after absorption, this is unlikely to be an important physiological mechanism.

Intravenous mixed amino acids and fats do not stimulate exocrine pancreatic secretion

We compared the responses of the canine exocrine pancreas to intraduodenal versus intravenous administration of mixed amino acids, fat emulsion, and glucose. Graded doses of amino acid mixture and of fat emulsion gave graded responses in volume, protein, and bicarbonate when administered intraduodenally. In contrast, the same doses of the amino acid mixture and fat emulsion administered by central intravenous infusion caused no significant pancreatic secretion of volume, protein, or bicarbonate. Graded doses of glucose caused no statistically significant pancreatic secretion whether they were given intraduodenally or intravenously. We conclude, contrary to a previously published observation, that amino acids and fats given parenterally do not stimulate pancreatic secretion. As a corollary, it is reasonable to assume that the pancreas is not stimulated during total parenteral nutrition with acute pancreatitis or a pancreatic fistula.

Wound infection after cholecystectomy: a case for routine prophylaxis

Wound infection after cholecystectomy is a not uncommon problem. A retrospective study of 227 cholecystectomies showed the incidence to be 15% when cholecystectomy alone was performed and 30% when a duct exploration was carried out without prophylactic antibiotics. These incidences were reduced to 3.6% and 3.4% respectively when prophylactic antibiotics were used. Though it has been possible to identify a high-risk group of patients, a truly low-risk group is not readily identifiable. It is concluded that prophylactic antibiotics should be given to all patients undergoing cholecystectomy.

Peroperative cholangiography: routine or selective?

The detection and removal of common bile duct stones remains a major challenge for the general surgeon. Peroperative cholangiography offers the most reliable method of detection and its routine use is now well accepted. This study of 262 cholecystectomies reassesses the value of this procedure and investigates the recent claim that cholangiography should be performed selectively rather than routinely. With routine cholangiography a positive exploration rate of 66% was achieved and retained stones occurred in 5% of patients with choledocholithiasis. Suggestions are made for ways in which the positive exploration rate could have been greatly improved. Had selective cholangiography been employed 47% of patients would have had the examination, the positive exploration rate would have been 70%, but the retained stone rate might have been 10%. In the light of this there appears little to commend selective cholangiography and we should continue to advise its routine use.

A case of advanced abdominal pregnancy

A case of advanced abdominal pregnancy is described, with survival of both the mother and a normal infant. Reasons for the failure to establish the correct preoperative diagnosis are discussed.