Mucin-producing biliary papillomatosis associated with gastrobiliary fistula.

We report a case of mucin-producing biliary papillomatosis in a 78-year-old woman. Abdominal ultrasound (US) and computed tomography (CT) showed wall thickening and dilatation of the intrahepatic bile duct (IHBD), as well as a nodular lesion, 1.2 cm in diameter, in the left branch of the IHBD. Gastric endoscopy revealed excretion of bile-containing mucin on the anterior wall of the body of the stomach. Endoscopic ultrasonography (EUS) showed gastrobiliary fistula and discharge of mucin into the stomach. Needle biopsy of the biliary tumor revealed papillary proliferation, but no malignant cells were recognized histologically. Therefore this patient was diagnosed as having mucin-producing biliary papillomatosis forming gastrobiliary fistula. She did not present with obstructive jaundice, probably because of the fistula. She is alive, without obstructive jaundice, 16 months after the diagnosis without having had surgery. This is, to our knowledge, the first reported case of biliary papillomatosis forming gastrobiliary fistula and with the patient free of obstructive jaundice.

A new drug delivery system for local cancer chemotherapy using cisplatin and chitin.

A new drug delivery system for local cancer chemotherapy was developed by chemical combination of chitin and cisplatin. When this material (Plachitin) was implanted in mice, high cisplatin concentrations were measured in the tissue around Plachitin for more than eight weeks without any nephrotoxicity. Local application of Plachitin improved the survival of mice previously implanted with Ehrlich tumor (p < 0.05). The present study indicates that Plachitin is a useful local agent for solid tumors due to its slow and sustained release of a large amount of cisplatin around the tumor without systemic side effects.

[An effective concentration method for human immunodeficiency virus type 1 (HIV-1)].

We designed an effective virus concentration method to prevent the infection with human immunodeficiency virus type 1 (HIV-1) in laboratories. The absorbent of Minicon concentrators (Amicon Division, M.R. Grace & Co.-Conn.) was changed to chitin, a mucopolysaccharide extracted from the shells of Japanese pink crab. HIV-1 in the supernatant of HIV-1 infected Molt-4 cells was concentrated by Minicon and the new concentrators. The new concentrator showed good concentration rate and equality of concentration speed.

[Scanning electron microscopic study of rat lungs in experimental chronic paraquat poisoning].

It is well known that Paraquat (1,1'-dimethyl-4,4'-bipyridylium dichloride), used widely as a herbicide, causes a primary toxic effect in the lungs of humans and laboratory animals. This paper describes the pulmonary changes of chronic paraquat poisoning in rats, comparing scanning electron microscopic findings. Twenty-four rats were given repeated injections of 10/kg body weight paraquat intraperitoneally for 6 consecutive months, and six control rats were given 0.9% NaCl solution. The animals exposed to paraquat showed thickening of alveolar septum, inflammatory cell infiltration, interstitial fibrosis, and marked proliferation of alveolar macrophages. Among them four rats (21%) showed the typical findings of diffuse pulmonary fibrosis. Lesions were more severe at the subpleural region of the lung. The desquamation of alveolar epithelial cells and subsequent exposure of the basement membranes were observed in places. Although alveolar epithelial cells both in the type I and the type II were prolific, the type II cells showed partial loss of microvilli and projections. These findings may indicate the lowering of the type II cell function and subsequent decrease of surfactant excretion which causes respiratory insufficiency. Furthermore, alveolar macrophages showed a tendency to increase in number with progressive development of fibrosis. This tendency may support the hypothesis by Schoenberger et al., in which alveolar macrophages release both fibronectin and a growth factor for fibroblast after paraquat exposure.

[Slow releasing anticancer drug containing CDDP for intraoperative use in residual cancer cells].

We have already reported the slow releasing property and anticancer effect of Plachitin, which is reconstituted by combination of CDDP and chitin. This study deals in more detail with the slow releasing property, and the renal complications and the effectiveness for solid tumor were examined. After implantation of Plachitin subcutaneously in the abdominal wall, the platinum concentration in the different organs was measured. In the abdominal muscle around the implanted Plachitin, a high concentration of platinum was maintained until 8 weeks and the peak was 4 weeks after implantation. At the same time, the serum concentration of platinum remained low. In kidney, the platinum concentration resembled the levels in the abdominal muscle, but no renal dysfunction was found serologically or histologically. When Plachitin was implanted around the solid tumor, the survival rates were improved and the gain in tumor weight was suppressed as compared with the controls. From these findings, Plachitin seemed to be effective as a slow releasing anticancer drug for topical application.

[Development of slow releasing anticancer drug based with absorbable biomaterial chitin].

To have a comparatively more slowly releasing anticancer drug with effectiveness, Plachitin was prepared by chemical combination of CDDP and chitin (poly-N-acetyl-D-glucosamine). Chitin is absorbed by the living body over several months. To investigate the slow releasing property, it was implanted in thigh muscle of mice and rabbit. Pt level in different organs and in urine was measured at regular intervals. Pt level in implanted muscles was higher in comparison to low serum level in mice. It was released slowly over 1 to 2 months in mice, whereas in rabbit it took about three weeks. Pt releasing period of the Plachitin was different according to the adopted method of implantation. Anticancer effect of Plachitin was investigated by injecting 180 sarcoma cells in mouse peritoneal cavity and subsequent implantation of Plachitin. In control groups chitin was used instead of Plachitin. The survival rate of mice in the Plachitin group after 14 days was higher than in the chitin group, and the anticancer effect of the Plachitin was confirmed.

[A new trial of plachitin particles for intraarterial chemoembolization therapy in rabbit].

Plachitin, which is reconstituted by the combination of CDDP and chitin, has been reported to have a slow releasing property of CDDP and an antitumor effect. The antitumor effect and pharmacokinetics of Plachitin for intraarterial chemoembolization therapy were studied in rabbits using VX2 tumor inoculated in the hind limb. One gram of Plachitin contained 300 mg CDDP, and the form of Plachitin was modified into particles (about 50 microns in diameter). Plachitin was injected into the femoral artery. The study was carried out in four groups. The tumor growth ratio was significantly lower in the Plachitin group than in the CDDP, chitin, and control groups (p < 0.05). Tumor regression was noticed only in the Plachitin group. The tumor platinum (Pt.) level was higher than the serum Pt. level for 5 days after Plachitin injection. From the above results it can be concluded that Plachitin particles released CDDP slowly around the tumor and the tumor growth was suppressed by the additive effect of CDDP and embolization. Plachitin was considered a useful agent for chemoembolization therapy for the cancer patients.

[Screening CT of the lungs: image quality compared with conventional CT].

More sensitive imaging methods may be required in the screening of early peripheral lung cancer. Among new radiologic techniques, helical volumetric computed tomography (CT) seems to be attractive. The image quality of helical CT with single breath-hold and low-dose technique (screening CT) was compared with conventional sequential CT in 12 patients to detect the pulmonary metastases. The screening CT protocol consisted of a 20 mm/sec table feed during a 20-second breath-hold at 40 mA, with reconstruction of images at 10 mm intervals. Conventional CT was performed with a 1-second scan time, 200 mA, and contiguous 10 mm-thick sections. In the evaluation of mediastinal vessels, bronchi and pulmonary nodules, screening CT showed high detectability images comparable to conventional CT. But subsegmental bronchi or small nodules overlapping pulmonary vessels were more difficult to visualize by screening CT because of image noise. The authors conclude that although further improvement is necessary, screening CT of the lung is an attractive new application of CT.

Chitin is an effective material for sutures.

Chitin is an absorbable suture material with suitable mechanical properties. Tissue reaction is not specific and the good healing which ensued provided evidence for a satisfactory biocompatibility. Toxicity tests, including acute toxicity, pyrogenicity, mutagenicity were negative in all respects. The chitin suture was absorbed in about four months in rat muscles. The persistence of the tensile strength of the chitin was better than Dexon (TM) or catgut in bile, urine and pancreatic juice but weakening occurred early in the presence of gastric juice. Application in 132 patients proved satisfactory. Adverse effects were nil.

Hemodynamics of small hepatic focal nodular hyperplasia: evaluation with single-level dynamic CT during hepatic arteriography.

OBJECTIVE: We examined the usefulness of single-level dynamic CT during hepatic arteriography to observe the hemodynamics of small hepatic focal nodular hyperplasia. CONCLUSION: Single-level dynamic CT during hepatic arteriography revealed not only centrifugal blood supply through the fibrous stellate scar, but also the drainage to dilated veins in or near the focal nodular hyperplasia nodule and directly to the hepatic sinusoid in the surrounding liver.

Malignant colonic obstruction due to extrinsic tumor: palliative treatment with a self-expanding nitinol stent.

OBJECTIVE: The purpose of this study was to evaluate the usefulness of self-expanding nitinol stents for palliative treatment of malignant colorectal obstruction caused by unresectable extrinsic tumor, colorectal metastasis, or peritoneal seeding. SUBJECTS AND METHODS: One covered stent and 10 uncovered stents were deployed in eight patients with colorectal obstruction due to extrinsic tumor under fluoroscopic guidance. The sites of obstruction were located in the rectum (n = 5), in the rectosigmoid colon (n = 2), and from the transverse colon to the descending colon (n = 1). Clinical usefulness and complications were analyzed. RESULTS: Stents were placed successfully in all patients. Minor modifications of the delivery system were required in the tortuous rectosigmoid and lower rectum strictures. Symptoms of obstruction were initially resolved in all but one patient. In that patient, the presence of other points of obstruction was suspected. Bowel obstruction recurred in two patients: one obstruction was due to migration of a covered stent 4 days after the procedure, and the other obstruction was due to peritoneal seeding 33 days after the procedure. Both required colostomy or ileostomy. All patients died 12-111 days after stent placement (mean, 56 days). In five patients (63%), colonic obstruction was palliated by placing a stent until the patients' death between 39 and 111 days after stent placement (mean, 62 days). Six complications occurred in four patients and included stent migration (n = 1), anal bleeding (n = 2), anal pain that required analgesia (n = 1), and fever (n = 2). CONCLUSION; This self-expandable nitinol stent adequately palliated 63% of patients with colonic obstruction due to extrinsic tumor in this small series. Patient selection is very important to the success of this treatment.

Subsegmental transcatheter arterial embolization for hepatocellular carcinoma in the caudate lobe.

PURPOSE: To clarify the effectiveness of transcatheter arterial embolization (TAE) for hepatocellular carcinoma (HCC) in the caudate lobe of the liver. MATERIALS AND METHODS: Thirteen patients with HCC in the caudate lobe underwent TAE. TAE was performed by injection of the mixture of anticancer drugs (mitomycin C and doxorubicin or epirubicin) and iodized oil, followed by gelatin sponge particles. Arterial anatomy of the caudate branch, local recurrence rate, and survival rate were evaluated. RESULTS: From 31 TAEs for the caudate lobe, 22 subsegmental TAEs were successfully performed (71%). Local recurrence in the caudate lobe was seen in 10 patients (77%). Subsegmental TAE for the caudate lobe was repeated one to five times. Cumulative local recurrence rates were 33% and 75% within 3 and 6 months, respectively. Survival rates after first TAE for HCC in the caudate lobe were 89% and 74% for 1 and 3 years, respectively. CONCLUSION: Local recurrence rate after subsegmental TAE for HCC in the caudate lobe was high. However, repeated subsegmental TAE possibly improves the prognosis of HCC in the caudate lobe.