Management of Complications from Hepatobiliary Surgery Using the Percutaneous Trans Jejunal Approach

Purpose

The work was aimed at presenting the indications, techniques and results of the percutaneous transjejunal approach to the biliary tree in patients with hepatobiliary complications due to surgery.

Patients and methods

Ten patients, 7 males and 3 females, mean age 50 years (range, 10–62) with hepatico-jejunostomy, who developed cholangitis together with jaundice or bile leakage, underwent this procedure, performed through the anastomotic loop that was not surgically anchored to the abdominal wall in all cases but one. The transjejunal approach was chosen because of non-dilated bile ducts in 3 patients, complex pathologic situations in 5 patients and to avoid complications to a transplanted liver in 2 patients. The jejunal loop was identified using CT, US and fluoroscopy in 4 patients and after its opacification in the remaining 6 (by percutaneous transhepatic or intravenous cholangiography or fistulography).

Results

The procedure was technically and diagnostically successful in all cases. Therapeutic procedures (stenting, dilation, litholysis) were also performed using the transjejunal approach in 7 patients and in 6 of them complete pathological resolution was achieved. There were no complications.

Conclusions

Different pathologies of the biliary tree, in patients with bilio-enteric anastomoses, have been identified and treated by this technique; they were fistulas, anastomotic and/or multiple segmental benign or malignant stenoses of the bile duct, and diffuse intrahepatic lithiasis. The procedure was safe and reliable.

Results of Radiotherapy in a Series of 250 Carcinomas of the Mucosal Surface of the Cheek

This paper presents the results of a retrospective clinical study of 250 cases of mono-centric carcinoma of the mucosal surface of the cheek, i. e. all the primaries treated by radiotherapy at our Institute between January 1948 and December 1965. Neoplastic lesions found at follow-up were regarded as marginal recurrences if in the proximity of the treated area and as secondary tumors in other cases. From 1948 to 1957 conventional radium therapy was the usual treatment for the primary tumor whereas from 1958 to 1965 cobalt teletherapy was given most frequently. Surgery was reserved for lymph node metastases when present on clinical examination. In our experience radiotherapy is effective in cancers of the mucosal surface of the cheek, for it checked local spread in 50.9 % of cases, however treated and regardless of initial clinical appearance, whereas in the T1-T2 cases the local failure rate dropped to 35.8 %. The higher the T level the greater are the difficulties confronting radiotherapy; for more extensive lesions appropriate combination therapy (radiosurgical) in line with the well-defined rules explained in the text is useful. In our experience radiotherapy yields good long term results regardless of T level and even in the more unfavorable cases. Our study confirms the low rate of lymph spread of these carcinomas: over half of the patients were NO before treatment; only 56.7 % of the patients receiving surgical treatment on the neck had histologically positive lymph nodes; there were very few neck recurrences at follow-up; the presence of suspect or frankly metastatic nodes on clinical examination, being movable and homolateral (N1), did not worsen the prognosis. However, considering the techniques used for irradiation of the primary, some patients received a substantial dose to the neck; hence radiotherapy probably played its part in the low rate of neck metastases.

Correlation between Clinical Response to Bilateral Oophorectomy, Estrogen Receptors and Urinary Androgen Excretion in 49 Patients with Advanced Breast Cancer

The aim of this study was to find out if it is possible to predict the clinical response to bilateral oophorectomy in premenopausal patients with advanced breast cancer. Two methods of determination were used before oophorectomy: 1) the presence of estrogen receptors in the tumor tissue; 2) the urinary concentration of androgens. The clinical response to oophorectomy was evaluated after a six-month follow-up. Determinations carried out on 49 patients showed that a significant correlation exists between clinical response to oophorectomy and androgenic activity alone or in combination with estrogen receptors when both tests give concordant results.

Percutaneous Intraductal Sampling for Cyto-histologic Diagnosis of Biliary Duct Strictures

Background

Percutaneous transhepatic biliary drainage (PTBD) allows ductal material to be collected for cyto-histologic examination. We evaluated the data from a large series of patients with a PTBD in whom endobiliary cyto-histologic sampling techniques were employed in order to define a strategy for their use in the diagnostic work-up.

Patients and Methods

Ductal samples for cyto-histologic examination were obtained from 409 consecutive patients with a PTBD for stenosing lesions of the biliary tree. Bile aspirate cytology was performed for all patients and ductal biopsy specimens were obtained, generally after negative cytology, from 49 of them (11.9%), all candidates for a therapeutic procedure. The cyto-histologic results of intraductal sampling were compared with pathologic surgical data in 210 patients and with clinical-radiologic follow-up in 199.

Results

Overall, 22 out of the 409 patients had a final diagnosis of benign stenosis and 177 had samples positive for neoplastic disease. The sensitivity of bile cytology was 43.8% while ductal biopsies showed a sensitivity of 60.4%. The combination of the two sampling techniques achieved a sensitivity of 65.1%. For both sampling methods the specificity was 100%. Hilar metastases from neoplastic lesions of the GI tract and primary lesions of the biliary ducts showed the highest sensitivity.

Conclusion

Cyto-histologic assessment of stenosing lesions of the biliary ducts is mandatory when highly sophisticated interventions (e.g. wide hepatic resection or liver transplantation) or non-surgical treatments are envisaged. The collection of cyto-histologic samples from bile ducts, in patients with a percutaneous bile drainage, is an easy, safe and valuable method to obtain the diagnosis. In view of the absence of false positive results in our series and in others, intraductal biopsy serves no purpose when positive exfoliative cytology is positive for malignancy. In the presence of negative cytology it is felt that an intraductal biopsy should be mandatory when the choice of a therapeutic program depends on the result of the cyto-histologic diagnosis.

Percutaneous Transhepatic Biliary Drainage in Malignant Obstructive Jaundice

Results obtained in 70 patients with neoplastic (primary or metastatic) biliary obstruction and submitted to percutaneous transhepatic biliary drainage indicate the effectiveness of the technique in relieving jaundice, improving general conditions and restoring liver function. In 25.4% of cases, the drainage allowed the patients to undergo surgical treatment of the neoplasm. In 74.6%, the drainage was left in place as definitive palliation. The complication rate was very low and similar to that described in the literature. At this time it is difficult to identify prognostic factors and foresee the results of percutaneous transhepatic biliary drainage, but the procedure is always indicated in patients at high operative risk or inoperable.

Interventional Radiology and Radiotherapy for Inoperable Cholangiocarcinoma of the Extrahepatic Bile Ducts

Aims and background

To evaluate the effectiveness of external radiation therapy (ERT), alone or combined with endoluminal brachytherapy (BRT), following percutaneous transhepatic biliary drainage (PTBD) in the treatment of patients affected by inoperable cholangiocarcinoma.

Methods & study design

From September 1980 to June 1996, 130 jaundiced patients affected by inoperable cholangiocarcinoma were submitted to PTBD at the Division of Radiology C of the National Cancer Institute of Milan. Nineteen were excluded from the present analysis due to the short survival after PTBD (<30 days). The other 111 patients were divided into three groups according to the following therapy: no further treatment after palliative PTBD in 89 patients (80%, group 1); ERT in 10 patients (9%, group 2); ERT plus BRT in 12 patients (11%, group 3). All the ERT+BRT patients were enrolled after 1990 and were treated with high-energy photon beams followed by en-dobiliary insertion of one or two iridium-192 wires.

Results

Median overall survival among the 111 assessable patients was 126 days; for groups 1, 2 and 3 it was 108, 345 and 428 days, respectively. The patients submitted to radiotherapy (ERT alone or ERT+BRT) were evaluated by radiologic examinations after the end of radiation. In group 2, a partial remission in 3 cases, a progression of disease in 1 case, and no change in 6 cases were observed. Among the patients of group 3, complete remission in 5 and partial remission in 7 patients were achieved. In all the patients achieving complete remission, the PTBD could be removed.

Conclusions

The combination of ERT plus BRT improves survival and quality of life of the patients submitted to PTBD for cholangiocarcinoma. Under the technical point of view, radiation treatment is easy to perform, but much caution is required in defining clinical and planning target volumes. Moreover, drainage during the radiation treatment has to be submitted to a very meticulous surveillance.

Accuracy of the Double Contrast Enema in Evaluation of the Abdominal Diffusion of Ovarian Carcinoma

The results of 103 double contrast enemas in 72 patients with ovarian carcinoma (stage III and IV) were compared with laparoscopic and/or laparotomic findings at comparable times. The evaluation of the validity of radiology in detecting the presence of abdominal disease showed an 84% overall accuracy, 75% specificity and 86% sensitivity. The accuracy in detecting signs of adhesion and parietal infiltration of the large bowel was 76.3%, due to the limited size of most of the lesions. Forty-seven of the 72 patients underwent a double contrast enema and laparoscopy during presurgical staging: accuracy in detecting lesions was the same for both examinations (80.4%). When double contrast enema and laparoscopy were used together in the evaluation of abdominal extension of the disease, the diagnostic accuracy rose to 93.6%.

Post-radiation Bone Lesions in Mammary Cancer

The radiographic patterns of post-radiation bone lesions in eight patients treated for breast cancer are described. Rib fractures - often multiple - at the anterior portion of the rib were observed in all patients. Two of them showed also lesions of the shoulder-blade, with a lesion in the humeral diaphysis in one. Only some of the eight patients have been heavily irradiated as far as the total dose, the diameter of the fields and the dose-time is concerned. In these cases the lesions were more severe and large in comparison to the other patients. Bone repair and reconstruction were not observed even after many years from initial treatment. Areas of overdosage at the level of bone structures may have occurred also in the other cases, where the usual therapeutical limits had not been overcome. This overdosage is likely to be due to the particular geometric relationships between neoplastic foci and thoracic wall, requiring several irradiation fields. From the radiographic point of view rib fractures are difficult to detect in their earlier phase; therefore the differential diagnosis has to be made with traumatic fractures. Later their recognition becomes easier though occasionally the problem of a differentiation from possible metastatic foci may arise.

Esophageal Carcinoma

Twelve minimal lesions were found over a period of 18 months at the Istituto Nazionale Tumori of Milan at the end of the radiologic, endoscopic and histologic procedures. Eleven lesions were radiologically detected, and a radiologic diagnosis of malignancy was perspectively made in 10 of the identified lesions. The radiologic aspects of minimal lesions are described. Double contrast study of the esophagus allows excellent mucosal detail and good reproduction of lesions. Simplicity and minimal discomfort for the patient justify it as a first diagnostic step for detection of neoplastic pathology.

Double Contrast Barium Enema Combined with Non-Invasive Imaging in Peritoneal Mesothelioma

Mesotheliomas are rare tumors arising from serosal linings of the major serous cavities. Five patients with peritoneal mesothelioma underwent a double contrast barium enema (DCBE) and ultrasonography (US) (2 patients), computed tomography (CT) (3 patients) and/or magnetic resonance imaging (MRI) (3 patients). The diagnosis was confirmed at laparotomy. The radiologic pattern at DCBE is unspecific and consists of compression and dislocation of bowel loops by extrinsic masses. Mesenteric retraction and segmental stenosis may be present. In one patient DCBE was normal. US, CT and MRI findings are also unspecific but when combined with information obtained from DCBE the site and abdominal extension of the disease are well defined.

Double Contrast Small Bowel Enema in a Case of Selective Duodeno-Jejunal Amyloidosis

Double contrast small bowel enema in a patient with selective amyloidosis of the duodenum and jejunum revealed an unusual radiologic pattern, mimicking multiple polyposis. Many submucosal polypoid lesions, sessile or pedunculated, were scattered throughout the duodenum and proximal jejunum. The lesions had smooth borders and did not show any retraction at the base. Other typical radiologic patterns of intestinal amyloidosis described in the literature were not observed in the present case. Differential diagnosis from multiple polyposis and diffuse lymphoproliferative neoplastic diseases is discussed.

Measles molecular epidemiology: What does it tell us and why is it important?

Measles molecular epidemiology was a key component of the verification of elimination of indigenous measles in Canada and is an invaluable tool during public health investigations, both to establish whether connections exist between concurrent measles cases and to indicate possible sources of importations. There are 24 distinct genotypes however the genotype is usually not sufficient to describe the complex molecular epidemiology of measles cases. The exact genetic sequence of the last 450 nucleotides of the nucleoprotein (N) gene (N-450) is used. The measles genome mutates very slowly and so cases within the same chain of transmission usually have identical N-450 sequences. In Canada, the National Microbiology Laboratory (NML) sequences the N-450 and deposits it into the WHO measles sequence database, MeaNS. This database can be used to identify other geographic regions where the measles sequence was detected, supporting or excluding connections. For commonly detected N-450 sequences, MeaNS designates a "sequence variant." Sequence variants are used as the defining characteristic of measles cases with identical sequences and this designation is fundamental to the description of measles molecular epidemiology both locally and globally. As progress is made towards global measles eradication, its genetic diversity decreases and distinct importations of measles from a single reservoir can be difficult to distinguish using current methods. Extending sequencing methods beyond the N-450 is required. While sequencing the entire hemagglutinin (H) gene, which is currently done routinely at the NML, can be helpful, whole genome sequencing will be required for effective molecular surveillance to monitor the sustained elimination of measles in Canada.insert text here.

Distribution of human papillomavirus types, cervical cancer screening history, and risk factors for infection in Manitoba

OBJECTIVES

We conducted a study to investigate the prevalence of human papillomavirus (HPV) infections in an opportunistic sample of women in Manitoba, Canada. We inquired about risk factors associated with HPV infections and linked the HPV typing results with the cervical cancer screening history of the participants.

METHODS

The study population included 592 women attending Papanicolaou (Pap) test clinics. After signing a consent form, participants were given a self-administered questionnaire on risk factors and received a conventional Pap test. Residual cells from the Pap tests were collected and sent for HPV typing.

RESULTS

The mean age of the population was 43 years. A total of 115 participants (19.4%) had an HPV infection, 89 of whom had a normal Pap test. Of those who were HPV-positive, 61 (10.3%) had high-risk (Group 1) HPV. HPV-16 was the most prevalent type (15/115: 13.0% of infections). The most consistent risk factors for HPV infection were young age, Aboriginal ethnicity, higher lifetime number of sexual partners and higher number of sexual partners in the previous year.

CONCLUSION

The prevalence of HPV types in Manitoba is consistent with the distributions reported in other jurisdictions. These data provide baseline information on type-specific HPV prevalence in an unvaccinated population and can be useful in evaluating the effectiveness of the HPV immunization program. An added benefit is in the validation of a proof of concept which links a population-based Pap registry to laboratory test results and a risk behaviour survey to assess early and late outcomes of HPV infection. This methodology could be applied to other jurisdictions across Canada where such capacities exist.

Type-specific prevalence of Human Papillomavirus infection among women in the Northwest Territories, Canada

BACKGROUND

Certain types of Human Papillomavirus (HPV) are highly associated with cervical cancer and precursor lesions (dysplasia), but the distribution of HPVs in Northern Canada is largely unknown. This study determined the prevalences of HPV infection due to different virus types and the association of different virus types with cervical dysplasia in the Northwest Territories (NWT).

METHODS

Between April 2008 and March 2009, women who underwent routine Pap testing in the NWT were included in the study. An in-house Luminex assay detected type-specific HPV infections. The HPV prevalence rates and population attributable risk fractions were calculated.

RESULTS

In 5725 bio-samples, the overall HPV prevalence was 24.2%, and of the HPV-positive samples, 76.6% harbored high-risk types, 35.2% harbored multi-type infections, and 21.6% harbored HPV16 or 18 infections. The HPV prevalence was approximately 50% higher among Aboriginal than non-Aboriginal women. The age-specific HPV prevalence exhibited a U-shape distribution in the Aboriginal group. The prevalence of HPV16 or 18 infections found in high-grade lesions was 34.1%. Among this study population, 89.5% of the cases with cervical dysplasia were attributable to HPV infection, with 27.1% attributable to HPV16/18.

CONCLUSION

The high prevalence of high-risk HPV in this population, particularly in the Aboriginal group, will require further studies to identify specific predictors of infection.

Genomic cartography of varicella-zoster virus: a complete genome-based analysis of strain variability with implications for attenuation and phenotypic differences

In order to gain a better perspective on the true variability of varicella-zoster virus (VZV) and to catalogue the location and number of differences, 11 new complete genome sequences were compared with those previously in the public domain (18 complete genomes in total). Three of the newly sequenced genomes were derived from a single strain in order to assess variations that can occur during serial passage in cell culture. The analysis revealed that while VZV is relatively stable genetically it does posses a certain degree of variability. The reiteration regions, origins of replication and intergenic homopolymer regions were all found to be variable between strains as well as within a given strain. In addition, the terminal viral sequences were found to vary within and between strains specifically at the 3' end of the genome. Analysis of single nucleotide polymorphisms (SNPs) identified a total of 557 variable sites, 451 of which were found in coding regions and resulted in 187 different in amino acid substitutions. A comparison of the SNPs present in the two gE mutant strains, VZV-MSP and VZV-BC, suggested that the missense mutation in gE was primarily responsible for the accelerated cell spread phenotype. Some of the variations noted with high passage in cell culture are consistent with variations seen in the IE62 gene of the vaccine strains (S628G, R958G and I1260V) that may help in pinpointing variations essential for attenuation. Although VZV has been considered to be one of the most genetically stable human herpesviruses, this initial assessment of genomic VZV cartography provides insight into ORFs with previously unreported variations.

Long-term results of balloon dilation of benign bile duct strictures

PURPOSE

To evaluate the results of percutaneous balloon dilation of benign bile duct strictures in a series of patients with a long follow-up period.

MATERIAL AND METHODS

56 patients with benign bile duct strictures underwent balloon catheter dilation. These patients had strictures of various origins: postsurgical, postlocal not surgical treatments, associated with gallstones, due to primary sclerosing cholangitis and to Mirizzi's syndrome. In 41 cases the diagnosis was made on the basis of radiological findings and history and in 15 cases on the basis of transluminal biopsy.

RESULTS

In 87.5% of cases the treatment was immediately successful. There were no early recurrences, but 7 (21%) recurrences were seen over 1 year after treatment; of these, 57% underwent another balloon dilation procedure with a positive long-term outcome.

CONCLUSION

The long-term success rate obtained in 72% of this series confirms that percutaneous bile duct dilation is a valid alternative to surgery without being burdened by complications; the procedure is also a valid alternative to the approach using endoscopic stents.

Long-term results of balloon dilation of benign bile duct strictures

PURPOSE

To evaluate the results of percutaneous balloon dilation of benign bile duct strictures in a series of patients with a long follow-up period.

MATERIAL AND METHODS

56 patients with benign bile duct strictures underwent balloon catheter dilation. These patients had strictures of various origins: postsurgical, postlocal not surgical treatments, associated with gallstones, due to primary sclerosing cholangitis and to Mirizzi's syndrome. In 41 cases the diagnosis was made on the basis of radiological findings and history and in 15 cases on the basis of transluminal biopsy.

RESULTS

In 87.5% of cases the treatment was immediately successful. There were no early recurrences, but 7 (21%) recurrences were seen over 1 year after treatment; of these, 57% underwent another balloon dilation procedure with a positive long-term outcome.

CONCLUSION

The long-term success rate obtained in 72% of this series confirms that percutaneous bile duct dilation is a valid alternative to surgery without being burdened by complications; the procedure is also a valid alternative to the approach using endoscopic stents.

Prevalence of human papillomavirus in Mazandaran Province, Islamic Republic of Iran

We report the prevalence of human papillomavirus (HPV) types in 100 cervical biopsy specimens in Mazandaran province. HPV DNA was detected in 78.6% of cervical carcinoma cases, 64.3% of dys/ metaplasia and 9% of normal cases. Significant correlation was found between the presence of HPV DNA and development of cervical carcinoma. HPV types 16 and 18 were detected in 60.6% of HPV-positive cervical carcinoma cases, whereas HPV31 and 33 were found in 21.2%, and HPV6 and 11 in 18.2%. Among HPV-positive dys/metaplasia cases, 55.6% were positive for HPV16 and 18, 22.3% for HPV6 and 11, and 11.1% for HPV31 and 33. Only HPV6 and 11 were detected in 4 (100%) normal biopsy specimens.

Diagnostic and interventional radiology in the post-operative period and follow-up of patients after rectal resection with coloanal anastomosis

Surgical treatment of carcinoma of the distal third of the rectum with anal sphincter preservation is increasingly used in accredited cancer centers. This study aimed to evaluate the diagnostic usefulness of radiological investigations in the management of patients who had undergone resection with coloanal anastomosis for carcinoma of the rectum, in the immediate post-operative period, during closure of the protective colostomy and in the follow-up of symptomatic recanalized patients. A total of 175 patients who had undergone total rectal resection with end-to-side anastomosis for carcinoma of the distal third of the rectal ampulla, most of whom had received postoperative radiotherapy, were evaluated radiologically. In the postoperative period radiological investigation was ordered only for symptomatic patients to detect pathology of the anastomosis and the pouch sutures and was used direct film abdominal radiography and contrast-enhanced radiography of the rectal stump with a water-soluble radio-opaque agent. Before closure of the colostomy, 2 months after rectal excision or approximately 4 months after if postoperative radiotherapy was given, the anastomosis and pouch of all patients, even asymptomatic ones, were studied with water-soluble contrast enema to check for normal canalization. In the follow-up after recanalization radiological examinations were done to complete the study of the large intestine if the endoscopist was not able to examine it up to the cecum. Of the 175 patients examined radiologically during the postoperative period and/or subsequent follow-up, 95 showed no pathological findings. Seventy-nine patients had fistulas of the coloanal anastomosis or the pouch, 23 of which supplied a presacral collection. In the absence of severe sepsis, the only therapeutic measures were systemic antibiotics and washing of the surgical catheters to maintain efficient operation. In 2 patients in whom transanal drainage was performed radiologically the fistula was cured in 1 week. In 36 cases of cicatricial stenosis, 17 at the coloanal anastomosis and 19 at the pouch, radiological examination always detected the lesion, correctly defining its anatomical characterisitics, nature and extension. Of the 19 cases of stenosis treated radiologically, 15 recovered an adequate intestinal calibre for tients operated on, 21 cases of reccurrence were detected. Radiological examination was requested as the first investigation in only one of these cases, for a patient with subocclusion. Radiological investigations in patients who have undergone colonanal anastomosis are of read diagnostic value in the immediate post-operative period, during closure of the protective colostomy and in the follow-up of symptomatic recanalized patients.

Percutaneous gastrostomy in oncologic patients: analysis of results and expansion of the indications

BACKGROUND

Percutaneous gastrostomy is generally performed for permanent enteral nutrition or gastric decompression.

METHODS

In our series of oncologic patients, percutaneous gastrostomy was also used temporarily in some patients for enteral nutrition while awaiting functional recovery of swallowing, in preparation for surgery, or for the treatment of fistulas in the upper digestive tract. Fifty-one procedures were performed in 50 patients: 42 for feeding, eight for decompression, and one for transgastric drainage of a duodenal fistula.

RESULTS

Of the 35 patients treated for permanent enteral nutrition, four are still alive, with a total survival time of 2,167 days. In three patients, gastrostomy was performed for temporary feeding and was removed once the ability to swallow was restored. In four patients, it was created to restore metabolic balance before surgery. In the patient with a duodenal fistula, healing was achieved in 19 days. The seven patients in whom the procedure was performed for decompression survived for a mean of 19.2 days. There was only one major procedure-related complication (peritonitis).

CONCLUSIONS

Percutaneous gastrostomy is a safe, low-cost method that allows the patient to maintain essential nutrition without the discomfort of a nasogastic tube and therefore warrants wider and earlier use. We feel that its application should also be extended to temporary feeding of patients about to undergo long courses of chemotherapy and radiotherapy, which can lead to severe deterioration of nutritional status.

TP53 mutations and mdm2 protein overexpression in cholangiocarcinomas

Tumor suppressor protein p53 is a positive regulator of MDM2 gene expression and the mdm2 protein can bind to p53, preventing the transactivation of p53 responsive genes, thus mimicking TP53 mutation. The authors looked for alterations that could affect, directly and indirectly, p53 function in 13 patients with extrahepatic cholangiocarcinoma. Molecular analysis by single strand conformation polymorphism and DNA sequencing revealed that TP53 gene mutations occurred in only 2 of 13 cholangiocarcinomas. High levels of mdm2 protein were found, by immunohistochemical staining, in 61% of the cholangiocarcinomas and in almost all specimens (70%) displaying stabilized p53 protein in the absence and in the presence of TP53 mutations. The finding of co-overexpressed mdm2 and p53 proteins in cholangiocarcinomas indicates that they can upregulate the expression of mdm2 protein to a level sufficient for binding and accumulating p53 in a presumably inactive complexed form. The presence of TP53 mutations or upregulation of MDM2 gene expression in 9 of the 13 cholangiocarcinomas strongly supports that the impairment of the p53 pathway is an important and specific step in cholangiocarcinoma pathogenesis. At variance with other authors, no alteration of p16ink4/CDKN2 gene was observed in all 13 cholangiocarcinomas.

In vivo study of polyurethane-coated Gianturco-Rosch biliary Z-stents

PURPOSE

Prototypes of Gianturco-Rosch Z-stents coated with polycarbonate urethane (PCU) were placed in the biliary tree of pigs, in order to test their biomechanical behavior, stability, and biocompatibility.

METHODS

The stents were surgically implanted in the common bile duct of three pairs of pigs, which were killed after 1, 3, and 6 months respectively. Explanted livers from pigs of the same race, age, and size were used to provide comparative data. The bile ducts were radiologically and histopathologically examined; the stents were processed and examined by scanning electron microscopy.

RESULTS

No complications occurred and the animals showed a normal weight gain. The main bile duct appeared radiologically and macroscopically dilated, but the stents proved to be in place. Histologically, the bile duct epithelium was destroyed, but neither hyperplastic nor inflammatory fibrotic reactions of the wall were evident. Both the metallic structure and the polymeric coating of the stents were intact. A layer of organic material with a maximum thickness of approximately 3 micron was evident on the inner surface of the stents.

CONCLUSION

The present in vivo study demonstrates the biocompatibility, efficacy, and stability of PCU-coated Gianturco-Rosch stents in the biliary environment.

Evaluation of temperature distribution during hyperthermic treatment in biliary tumors: a computational approach

A computational approach is adopted to predict the temperature distribution in the biliary tissue during hyperthermic treatments in biliary tumors. Two different models are developed: an axisymmetric model and a three-dimensional model. In the first model the Pennes bioheat transfer equation is applied. It is aimed at simulating the thermoregulatory effect of the capillary bed and it can also give a pressure criterion to determine whether the blood perfusion term should be included in the mathematical model. The second model is aimed at simulating the convective effect of the large hepatic vessels: A constant Nusselt number is assumed on the sides of the vessels. The simulations of the three-dimensional model have been carried out with and without capillary perfusion in the tissue, i.e., respectively in the worst case and in the best case that may occur during heating. The results show that it is possible to obtain therapeutic temperature values in the tissue for time intervals considered acceptable by physicians. Moreover, the model is able to give more precise information about the volumes of tumoral tissue heated above therapeutic temperatures with the hyperthermic technique considered.

Comparative in vitro sensitivity of human cholangiocarcinoma and colon adenocarcinoma cells to anticancer agents

We comparatively investigated the sensitivity of a human cholangiocarcinoma cell line (SG231) and an adenocarcinoma cell line (WiDr) to mitoxantrone (MX), taxol (TX), mitomycin C (MMC), doxorubicin (DX), cisplatin (CDDP) and 5-fluorouracil (5FU) by the sulforhodamine B assay. The lower susceptibility of SG231 to SFU, to CDDP, to DX and to MMC than WiDr was observed, whereas the sensitivity of the two cell lines to MX and TX was similar. We also investigated the ability of a chemical modulator, lonidomine (LND), and hyperthermia to enhance the cytotoxic activity of the different drugs in the SG231 cell line. No potentiation of MX or CDDP activity was observed after a 2 hours treatment in hyperthermic conditions (42 degrees C). Conversely, a slight potentiation of a 2 hours pretreatment with MX and DX was obtained by a 24 hours post treatment with LND.

Branched structures in the intracellular DNA of herpes simplex virus type 1

Herpes simplex virus type 1 (HSV-1) replication produces large intracellular DNA molecules that appear to be in a head-to-tail concatemeric arrangement. We have previously suggested (A. Severini, A.R. Morgan, D.R. Tovell, and D.L.J. Tyrrell, Virology 200:428-435, 1994) that these DNA species may have a complex branched structure. We now provide direct evidence for the presence of branches in the high-molecular-weight DNA produced during HSV-1 replication. On neutral agarose two-dimensional gel electrophoresis, a technique that allows separation of branched restriction fragments from linear fragments, intracellular HSV-1 DNA produces arches characteristic of Y junctions (such as replication forks) and X junctions (such as merging replication forks or recombination intermediates). Branched structures were resolved by T7 phage endonuclease I (gene 3 endonuclease), an enzyme that specifically linearizes Y and X structures. Resolution was detected by the disappearance of the arches on two-dimensional gel electrophoresis. Branched structures were also visualized by electron microscopy. Molecules with a single Y junction were observed, as well as large tangles containing two or more consecutive Y junctions. We had previously shown that a restriction enzyme which cuts the HSV-1 genome once does not resolve the large structure of HSV-1 intracellular DNA on pulsed-field gel electrophoresis. We have confirmed that result by using sucrose gradient sedimentation, in which both undigested and digested replicative intermediates sediment to the bottom of the gradient. Taken together, our experiments show that the intracellular HSV-1 DNA is held together in a large complex by frequent branches that create a network of replicating molecules. The fact that most of these branches are Y structures suggests that the network is held together by frequent replication forks and that it resembles the replicative intermediates of bacteriophage T4. Our findings add complexity to the simple model of rolling-circle DNA replication, and they pose interesting questions as to how the network is formed and how it is resolved for packaging into progeny virions.

Polyurethane-coated, self-expandable biliary stent: an experimental study

RATIONALE AND OBJECTIVES

We describe a self-expanding metallic biliary Gianturco-Rösch stent coated with polymeric material. The coating was designed to prevent the growth of neoplastic and reactive tissue within the biliary ducts.

METHODS

The stents were coated with a solvent-casting technique, which consists of dissolving polyurethane (polyether urethane or polycarbonate urethane) pellets in a solvent (dimethylacetamide), dipping the stent in the solution, and completely evaporating the solvent. In vitro mechanical characterization of the stent was performed to determine the adhesion of the coating to the metallic cage, the best introducer caliber for implantation of the device, and the relationship between the stent's diameter and radial stress.

RESULTS

Reports in the literature on the biostability of polycarbonate urethane compared with polyether urethane prompted us to use the former material to coat the stents. The solvent technique gives a smooth internal surface of the stent wall, leaving in relief the coated structure of the stent on the external surface. The functional tests demonstrated that the coating did not compromise the original characteristics of the stent in terms of self-expandability, axial flexibility, and increased radial rigidity of the device.

CONCLUSION

Functional tests verified coating stability and device handling, which are the first steps toward in vivo experimentation.

Suprapubic cystotomy as treatment for severe hemorrhagic cystitis after bone marrow transplantation

We analyzed the success of suprapubic cystotomy in patients with severe hemorrhagic cystitis after bone marrow transplantation. Seventy-three out of 963 patients developed severe hemorrhagic cystitis which resulted in urinary tract obstruction after high-dose cytoreductive therapy. Eleven patients (15%) failed medical treatment and required emergency suprapubic cystotomy. Three of these patients died of other complications prior to resolution of HC. Of the remaining 8 patients who underwent surgery, 4 are alive. The mortality rate was significantly higher in patients who required surgery than in those who responded to medical therapy. Patients whose HC required surgery also had a greater transfusion requirement than those who responded to medical therapy. We conclude that surgical treatment of severe HC should be undertaken only after failure of medical therapy.

Mechanism of inhibition of duck hepatitis B virus polymerase by (-)-beta-L-2',3'-dideoxy-3'-thiacytidine

We have used the endogenous reverse transcriptase reaction of viral core particles from duck liver to elucidate the mechanism of inhibition of duck hepatitis B virus (DHBV) replication by the nucleoside analog (-)-beta-L-2',3'-dideoxy-3'-thiacytidine (3TC). As is the case in human immunodeficiency virus replication, 3TC-5'-triphosphate (3TC-TP) acts as a chain terminator for the DNA polymerase activities. The results of several different experiments support this conclusion, which explains the potent activity of 3TC against the hepadnaviruses. In isolated DHBV core particles, 3TC-TP inhibited the reverse transcriptase in a manner that resembled competitive inhibition with respect to dCTP. However, the kinetics of inhibition was not linear on a double-reciprocal plot for the highest concentrations of 3TC-TP and the lowest concentration of dCTP. This anomaly would be expected if binding to the nucleotide site was followed by DNA chain termination. Calculations that used only the linear part of the curve yielded a Ki of 0.78 +/- 0.10 microM 3TC-TP. The inhibition of core particles incubated in vitro with 3TC-TP was not reversed by removal of the free inhibitor. 3TC-TP inactivated the reverse transcriptase activity in a concentration-dependent manner. The Km of the chain termination reaction was calculated at 0.71 +/- 0.05 microM. Similar competitive kinetics and irreversible inhibition were also obtained on the endogenous DNA polymerase from viral particles from serum, suggesting that 3TC-TP also acts as a chain terminator of the DNA-directed DNA polymerase of DHBV replication.(ABSTRACT TRUNCATED AT 250 WORDS)

[Transcutaneous radiotherapy combined with low dose intraluminal brachytherapy in the treatment of non-operable neoplastic stenoses of the bile ducts]

Percutaneous biliary drainage is an excellent method to relieve the acute symptoms related to neoplastic stenoses of extrahepatic bile ducts. However, survival rates are low and the quality of life of these patients is poor. High dose irradiation--combined with external beams (ERT) and intraluminal brachytherapy (BRT) through percutaneous drainage--allows effective disease control and, therefore, not only higher survival rates but also a much better quality of life when drainage can be removed after bile duct stenosis resolution. March, 1990, through March, 1993, eleven patients (8 with extrahepatic cholangiocarcinomas and 3 with extrinsic tumors) were treated with combined ERT (40-60 Gy, 6-15 MV X-rays) and intraluminal BRT (6-25 Gy, 192Ir wire, LDR). In 8 patients the biliary stenosis was resolved, completely (CR) in 5 and partially (PR) in 3, as shown by posttreatment cholangiography. In 5 patients biliary drainage could be removed for an average 9 months' period; 3 of 11 patients did not respond to treatment at all (NR). Average overall survival was 14 months: 11 months for NR patients and 16.5 months for CR+PR patients. Treatment complications were acceptable: in two patients only treatment had to be discontinued, both during BRT. Two cases of high grade postirradiation stenosis were observed, both resolved with percutaneous cholangioplasthy.

[Use of safety catheter after removal of Kehr's tube in liver transplant patients]

The authors report on the use of a safety catheter when removing the T-tube in the patients with choledocho-choledochal biliary reconstruction after liver transplantation. After T-tube removal, bile may leak into the peritoneal cavity through the catheter insertion site in the biliary wall. Biliary peritonitis, bilomas, subhepatic collections may develop, which are difficult to treat in immunodepressed patients. The safety catheter is used to allow the external drainage of the biliary outflow, if present, and to prevent the complications due to bile collecting in the peritoneal cavity. Moreover, the catheter allows cholangiography and interventional procedures to be performed when necessary. A soft guidewire is inserted into the distal bile duct through the T-tube and pushed into the duodenum. After removing the T-tube, an 8.3-F all-purpose catheter (APD) is placed on the guidewire with the tip just outside the biliary wall. The APD is then connected to a drainage bag allowing the amount of bile eliminated daily to be checked. This maneuver was performed in 24 transplant recipients and the safety catheter correctly positioned in 22 of them (91.6%). The APD was removed 48 hours after insertion in 15 patients with no biliary leakage. In the remaining 7 patients the catheter was left in situ up to 8 days, since biliary leakage was observed (range: 50-400 ml/day). No early or late complications related to this technique were observed.

[Self-expanding metal stents in the treatment of neoplastic esophageal stenosis. The technic and preliminary results]

Self-expanding metal stents have been recently used for the treatment of neoplastic esophageal stenoses. In our series, nitinol Strecker stents were implanted in ten patients with malignant esophageal intrinsic or extrinsic strictures, as a definitive palliation. Thirteen stents in all were used: two stents were positioned in three patients to recanalize the esophagus. The prostheses could always be inserted in the treated patients and in all of them swallowing was markedly improved. No major early complications were observed after stent insertion. All the stents but one were patent until the patient's death. Two patients are alive and bearing well-functioning stents. Self-expanding metal stents are to be preferred to plastic endoscopic tubes because their caliber is smaller at the time of insertion and they do not require general anesthesia, as endoscopic tubes sometimes require. Moreover, their complication rate is lower for both early and late complications. Tumor ingrowth through the stent mesh with stent occlusion is the major pitfall of these prostheses, together with the impossibility to use them when esophageal fistulas are present: these limitations will be soon overcome when silicone-coated expandable stents are on the market.

Study of the structure of replicative intermediates of HSV-1 DNA by pulsed-field gel electrophoresis

DNA from HSV-1-infected cells was separated by pulsed-field gel electrophoresis into two virus-specific bands: one that migrated as the linear monomer genome (152 kb) and another that remained at the origin of the gel. The latter band contained the replicating HSV-1 DNA, as determined by pulse-labeling with [3H]thymidine. To investigate the structure of this "gel origin" DNA, we constructed a HSV-1 KOS mutant bearing a unique PacI restriction site (HSV-1 PAC1DTK). Partial digestion of gel origin PAC1DTK DNA at late times postinfection (24-48 hr) demonstrated the presence of linear concatemers on pulsed-field gel electrophoresis. Within each concatemer, the long (L) regions of adjacent monomer genomes were found in the two possible orientations. In addition, shorter-than-unit-size fragments that corresponded in size to the left end fragments of the viral genome were detected with the UL region in the two possible orientations. At early times postinfection (8-12 hr), digestion with PacI released only a trace of linear fragments, and most of the gel origin DNA did not migrate on pulsed-field gel electrophoresis. Multiple cuts with EcoRI (a restriction enzyme that cuts the HSV-1 KOS genome 12 times) were necessary to release linear fragments that migrated from the origin of the gel. These results indicate that replicative intermediates of HSV-1 DNA are linked in a large network that needs to be unraveled before packaging takes place. This network may be composed of linear molecules linked together by frequent recombination events or of products of a mode of replication other than simple rolling circle (e.g., theta replication).

[Digital fluorography in gastroenterological radiology]

The clinical value of two digital fluoroscopy systems not connected to a PACS was investigated and compared with that of conventional radiology. Some critical variables were considered: image intensifier diameter, image definition, examination time, acquisition speed, patient exposure and finally film consumption. The main problems in the use of the digital techniques consisted in the limited size of the examination fields, which was not big enough to demonstrate the whole colon during double contrast enema, and in the difficult representation of the actual size on the image printed on the laser films. Definition was considered as sufficient for GI examinations. The main advantages consisted in acquisition speed, allowing detailed examinations of cervical esophagus, cardias and fistulous tracts, reduced patient dose and finally the real time visualization of the acquired image on the TV monitor.

The outcome of cholangitis after percutaneous biliary drainage in neoplastic jaundice

The purpose of this paper is to evaluate factors affecting the outcome of cholangitis after PTBD in jaundiced cancer patients. Twenty nine patients with neoplastic jaundice (male/female ratio 13/16, median age 55 years) with full clinical data, were treated by PTBD and developed cholangitis at a median of 9 days later. Four patients (14%) died of biliary sepsis a median of one month after PTBD while the other 25 survived a median of 6 months, with one week median duration of cholangitis. The probability of the cholangitis resolving was analyzed by time to resolution and it was found that 50% and 100% of the recoveries occurred 5 and 9 months respectively from the onset of the complication. The series was analyzed to determine the role of several variables (disease/patient/treatment related) in the resolution of cholangitis. Only a low stricture site, a large initial drainage catheter (10F) and a temperature increase exceeding 39 degrees C were correlated with a positive outcome. We conclude that PTBD-related cholangitis has, in our experience, a good chance of cure, low mortality rate and satisfactory 6 months median survival.

[Percutaneous gastrostomy]

Percutaneous gastrostomy was developed over the last years as an alternative method to surgical and endoscopic procedures, either for enteral feeding or for drainage of secretions or fluid collections communicating with the upper gastrointestinal (GI) tract. January 1990 through January 1992, 15 percutaneous gastrostomies and 2 percutaneous jejunostomies were performed at the Gastroenterologic Radiology Division of INT, Milan, Italy. The catheters were always inserted under local anesthesia, generally using special gastrostomy sets. Catheter insertion was possible in all the patients who underwent the procedure: in 12 cases gastrostomy allowed enteral feeding till the patients died and in 1 case the catheter is still working. In 2 cases the procedure was performed for drainage of gastroenteric secretions and the catheter was left in situ as a definitive palliation. In 1 patient the catheter was removed after draining a collection due to an anastomotic fistula. No major complications were observed in 17 procedures. In our experience, the indication according to which percutaneous gastrostomies and jejunostomies were performed for enteral feeding was always affected by the presence of a stenosis, in the upper GI tract. Other indications to the procedure, for enteral feeding, are functional swallowing disorders. Finally, it must be emphasized that when tight stenoses of the upper GI tract are present, percutaneous gastrostomy is the sole alternative to surgery.

Diagnostic accuracy of the double-contrast enema for colonic polyps in patients with or without diverticular disease

The accuracy of the double-contrast enema for the diagnosis of polypoid lesions in the presence or absence of diverticula was evaluated by retrospectively reviewing the medical records of 202 patients subjected to examination and endoscopy. Analysis of the data on 215 polypoid lesions showed that (a) the diagnostic accuracy of the examination is not affected significantly by the presence of diverticula; (b) the sensitivity of the examination is highly dependent on the size of the polyps (smaller or larger than 0.5 cm) but not on the form (sessile or pedunculated); and (c) the positive predictive value is higher in patients without diverticula. The double-contrast enema was confirmed to be a valid method for the diagnosis of polypoid lesions.

[Prognostic factors after percutaneous transhepatic biliary drainage]

The authors reviewed the clinical charts and the radiographic files of 93 patients with obstructive jaundice--in 86 cases due to neoplasm--treated with PTBD. The test of differences from survival curves was used to identify the clinical parameters predictive of short survival after PTBD. The difference in survival curves was significant relative to serum indirect bilirubin (cut point: 7.6 mg%), to serum cholinesterase (cut point: 1290 mU/ml), to white blood cell counts (cut point: 8600/mm3), to blood urea nitrogen (BUN) levels (cut point: 60 mg%). Because of the marked negative prognostic value of high BUN levels, our data seem to indicate that PTBD should not be performed when severe renal insufficiency is present. Other parameters correlated with a short survival after PTBD were the histotype of metastasis (in comparison with the other ones), and large neoplastic volume (in comparison with a small and a medium ones). Through pre-PTBD radiological and laboratory data analysis, a group of patients can be selected in whom the procedure will increase neither well-being nor survival, as plotted against those patients who are likely to benefit from biliary drainage.

An assay for proteinases and their inhibitors based on DNA/ethidium bromide fluorescence

Proteinases and their inhibitors have become the subject of intense research interest recently, since they control a multitude of very important biological processes, from the development of lambda phage to hypertension in humans. We have developed a simple and sensitive assay for detecting the activity of proteinases and of their proteinase inhibitors. The assay is based on ethidium bromide fluorescence, according to the following principles: (i) Ethidium bromide increases its fluorescence by 25-fold when it intercalates between base pairs of double-stranded DNA. (ii) Histones prevent this large increase in fluorescence by binding with high affinity to DNA thus blocking ethidium bromide intercalation. (iii) A proteinase that digests histones will make more DNA available for ethidium bromide intercalation, thereby producing an increase of fluorescence. Proteinase activity can easily be determined, in the presence of a DNA/histone complex, from the rate of ethidium fluorescence increase. In contrast, activity of a proteinase inhibitor is quantitated by the inhibition of fluorescence gain in the presence of a known amount of proteinase. This assay is rapid, simple, inexpensive, and, at the same time, accurate and sensitive enough to allow quantitation of nanogram amounts of various broad-specificity proteinases and their inhibitors. We show some possible applications of the assay (i) in testing column fractions during protein purifications, (ii) quantitation of alpha 1-antitrypsin in human serum, and (iii) detection of proteinase activity in cell extracts.

Double contrast small bowel enema in a case of selective duodeno-jejunal amyloidosis

Double contrast small bowel enema in a patient with selective amyloidosis of the duodenum and jejunum revealed an unusual radiologic pattern, mimicking multiple polyposis. Many submucosal polypoid lesions, sessile or pedunculated, were scattered throughout the duodenum and proximal jejunum. The lesions had smooth borders and did not show any retraction at the base. Other typical radiologic patterns of intestinal amyloidosis described in the literature were not observed in the present case. Differential diagnosis from multiple polyposis and diffuse lymphoproliferative neoplastic diseases is discussed.

[Use of Severini's coaxial catheters in gastrointestinal interventional radiology]

The growing importance of gastrointestinal interventional radiology has led to the development of new instruments and materials for the different proposed purposes. The authors present a set consisting of two coaxial catheters which was created for percutaneous transhepatic biliary drainage (Severini set). Its easy handling, adaptability and tolerability make it a versatile instrument in the hands of interventional radiologists for positioning large-calibre catheter (9-14 F) in deep sites. Hereafter are reported the results in 29 patients treated with different therapeutic aims and the use of the set for different pathologies. The catheters allowed a complete resolution of the collections communicating with the gastrointestinal tract in 4 of 5 patients. The catheter was inserted as a feeding tube in 22 patients. Finally, it was used as a gastrostomy catheter in 2 patients. Neither early nor late complications due to insertion or use of this set were observed.

Interconversion of replication and recombination structures: implications for terminal repeats and concatemers

Replication and recombination structures can be interconverted by branch-migration. Using this simple concept a novel mechanism is proposed for generating concatemers through an initial single-strand DNA invasion into a duplex. Only DNAs with terminal repeats can form concatemers, and Herpes Simplex Virus DNA replication is considered in detail. The model is more parsimonious than other models such as Watson's for concatemer formation.