A novel endoscopic marker: safety experiments in the rat stomach.

BACKGROUND AND STUDY AIMS: The study aimed to assess a newly developed endoscopic marker designed to cause only minor inflammatory reactions. MATERIALS AND METHODS: Chitosan and carbon powder were used in the marker substance. The product was a viscoelastic solution, which was injected into the submucosa in rat stomach walls. The tissue reactions were then examined histopathologically. The structure of the injected marker substance was examined with electron microscopy into rat stomach walls. India ink, which is currently used as an endoscopic marker, served as the control. RESULTS: Histopathological examination showed that inflammatory reactions with the novel agent were remarkably mild in the rat organs, while submucosally applied india ink caused severe inflammation in situ. The electron-microscopic findings showed that the carbon particles used were completely spherical in shape and that the carbon in the marker substance was entrapped in the chitosan networks. The india ink was shown to consist of a mixture of fine carbon particles and adhesive additives. CONCLUSIONS: The chitosan-carbon solution appears to be a promising endoscopic marker substance, causing significantly reduced inflammation.

[Novel biodegradable materials for drug delivery systems (DDS)].

The authors provide three new and different types of fibrin gels (FCs) and a chitosan sheet (BC) using an ultraviolet (UV)-crosslinking method. They are 1) FC-UV, 2) gelatin entrapped FC; FC (Gp)-UV, 3) chitosan entrapped FC; FC (Cs)-UV and 4) BC-UV. Each material was loaded with aqueous cis-platinum (CDDP), and both the degradation of the drug carriers and the release profile of the CDDP were examined in vitro. The FCs, 1)-3), gradually degraded and dissolved within 10-12 days. The BC, 4), maintained its original weight for more than 30 days. Each FC showed a sustained release of CDDP for 10 days, while BC provided an initial bursting of the loaded drug. New materials 2) and 3) show great potential as drug carriers for DDS and further in vivo studies are now proceeding.

[A newly designed system, "FC-UV-CDDP", and a study of its oncolytic effect].

We devised a fibrin clot (FC) using an ultraviolet (UV)-crosslinking method. To evaluate the in vivo chemotherapeutic effects for cancer chemotherapy with our novel drug delivery system, the anticancer agent cis-platinum (CDDP) was impregnated into each FC and this "FC-UV-CDDP" was intraperitoneally (i.p.) administered to each ascitic hepatoma AH-130 in cancer-bearing rats. Other groups of AH-130 bearing rats, i.p. injected with CDDP or non-treated, served as the controls. We recorded the survival period of each animal and autopsied it at the time of death. All the animals treated with "FC-UV-CDDP" survived for more than 5 weeks and had no retention of ascites. Furthermore, all the surviving rats underwent a challenge with AH-130 cells. Two of 3 repeatedly challenged rats revealed no evidence of recurrence of the cancer and survived for more than 3 months. The control rats died of cachexia with a massive ascites within 2 weeks. Thus, our newly devised "FC-UV-CDDP" system favorably functioned in an experimental cancer model. These data suggested that this oncolytic effect was attributed to the possibility of inducing immune responses against AH-130 as well as to a sustained release of CDDP from FC.

[A novel fibrin clot with a sustained release of cis-platinum (CDDP)].

The authors devised a novel fibrin clot (FC) using an ultra-violet (UV)-crosslinking method. CDDP was impregnated into FCs, and the release profiles of the CDDP were examined in vitro. The microstructures of the FCs were studied with scanning electron microscopy (SEM). The release of CDDP from the FC-UV-CDDP was maintained for 10 days, while that from the FC-CDDP showed initial bursting with a following plateau of CDDP concentrations. SEM of UV-crosslinked FCs revealed highly organized, close and homogeneous micropore structures. Native FCs and non-crosslinked FCs showed rough fibrin networks with entangling fibrin fibers. These microstructural differences may play important roles in the release profiles of CDDP. Our newly devised UV-crosslinked material is promising as a drug carrier for sustained release.

[A case report of stage IV ovarian carcinoma treated with cancer chemotherapy and surgery].

A 53-year-old female in PS grade 4 was admitted to our hospital in April, 1992, with dyspnea and abdominal distention persisting for 1 month. An abdominal echogram suggested a malignant lesion of the left ovary with ascites and a chest radiogram showed massive effusion in the right pleural cavity. Cytology of the effusions confirmed adenocarcinoma. Supposing that both the ascites and the pleural effusion were due to metastases from the primary ovarian carcinoma, we soon carried out systemic cancer chemotherapy and bio-adhesio-chemo (BAC) therapy) in the right pleural space. In July, the patient underwent left oophorectomy. The tumor removed measured 23 x 18 x 11cm. Histology revealed an endometrioid adenocarcinoma of the left ovary. We placed small pieces of fibrin clots encapsulating CDDP in the abdominal cavity of the patient to prevent the recurrence of cancer. Postoperatively, the patient markedly improved to grade 0 in PS and could be discharged 2 months later. She has been receiving systemic cancer chemotherapy with periodical checkups. No evidence of either recurrence or metastasis has been observed. We obtained favorable results with our own types of therapy against advanced ovarian carcinoma.

[Locoregional therapy in patients with malignant pleural effusion--two different types of "BAC therapy"].

We used fibrin clot (FC) as a carrier of anticancer drug (AD) to provide a novel therapy for patients with serious malignant pleural effusion. After evacuating the pleural fluid, we enhanced an "FC-AD" formation in the pleural cavity of the patient to prevent this kind of effusion from reaccumulating. In an attempt to enhance FC-AD formation, we used two different procedures; either, fibrinogen/AD/G.T.XIII (procedure I) or fibrin glue/AD (procedure II). G.T.XIII is our newly devised compound drug, composed of biodegradable gelatin (G), thrombin (T) and a blood coagulation factor XIII (XIII). This therapy was termed "Bio-Adhesio-Chemo (BAC) therapy." We conducted BAC therapy 52 times on 44 patients using procedure I and 4 times on 4 patients using procedure II. Complete remission of the effusion was obtained, overall, in 83%, partial remission in 17%, and no non-effective case. The improvement of PS of the patients treated was 73%. Nineteen patients could be discharged with this therapy. Toxic effects with BAC therapy were within Grade 2 in all cases. We could favorably enhance FC-AD formation, in every case, by both procedure I and II. BAC therapy is very promising as a novel cancer chemopleurodesis for patients with malignant pleural effusion.

[A loco-regional cancer chemotherapy, using a fibrin clot as a drug carrier--the oncolytic effects and putative mechanisms].

Anticancer drug (AD), adriamycin (ADM) or cisplatinum (CDDP) were individually encapsulated into an insoluble fibrin clot (FC), using our own technique. FC-ADM or FC-CDDP was intraabdominally placed in AH 130-bearing rats, and ADM or CDDP solution was intraabdominally injected (IP) into other cancer-bearing rats. The survival time was recorded and related oncolytic mechanisms were investigated. Eleven of 14 rats treated with FC-CDDP, and four of eight rats given FC-ADM, survived for more than 200 days. In these animals, the ascites disappeared within 10 to 14 days after the treatment, and there was neither a recurrence of ascites nor metastases. Eight of these rats underwent challenge of AH 130 cells. All the challenged animals revealed no evidence of recurrence of the cancer and showed a killing activity against the AH 130 cancer cells. Survival time in the other cancer-bearing rats was shorter than three weeks, and the direct cause of death was cachexia. Our newly devised FC-AD showed high activity against implanted AH 130 tumors. These activities are attributed to both a sustained release of AD and immunoresponses induced with FC-AD.

A newly designed anticancer tumor immunity drug delivery system.

The authors used a fibrin clot (FC) as a carrier of an anti-cancer drug (AD) to achieve sustained release of the drug. Adriamycin (ADM) and cis-platinum (CDDP) were individually encapsulated into an FC, and the profile of release of each AD from the FC-AD was examined in vitro. The FC-AD was placed intra-abdominally in ascites hepatoma AH130-bearing rats, and ADM or CDDP solution was intraperitoneally injected (IP) into other cancer bearing rats. The survival time was recorded, and related oncolytic mechanisms were investigated. The release of AD from the FC continued for over 15 days. Sixty-eight percent of the rats treated with FC-AD survived for more than 200 days and evidence of malignancy disappeared. Almost all of the IP rats and non-treated rats died within 20 days; these animals had massive ascites and extensive metastases. Immunologic studies confirmed that various tumor immunoresponses were induced in the rats treated with FC-AD. The FC-AD system warrants further study for possible antineoplastic activities in vivo.

[Loco-regional cancer chemotherapy in patients with malignant pleural effusion--improving the QOL of patients].

We carried out a new loco-regional cancer chemotherapy for serious patients with malignant pleural effusion, in an attempt to prevent the recurrence of effusion. After removing pleural effusion, fibrinogen solution, anticancer agent and our newly devised compound drug, "G.T.XIII" were intrapleurally instilled to enhance an anticancer fibrin membrane. This pleurodesis was called "Bio-Adhesio-Chemo (BAC) therapy". Some 39 BAC therapies were carried out for 34 patients. There were 32 cases evaluable; 29 resulted in PR, and three were NC. Improvement of P.S. was observed in 77% (30/39). Aggravation of P.S. was nil. Sixteen patients were discharged after showing favorable improvement. Toxic effects with the therapy were rather mild. Such results were attributed to the biomechanism of both the adhesive and oncolytic effects of the fibrin membrane enhanced with BAC therapy. Immunological studies suggested that the fibrin membrane also worked as BRM in the pleural cavity. Our own BAC therapy showed a great potential in improving the QOL of patients with malignant pleural effusion.

[Loco-regional cancer chemotherapy with a new drug delivery system, "anticancer drug-fibrin clot"].

Five different types of anticancer drugs were individually entrapped into fibrin clots using our own material, "G.T.XIII" to provide an "anticancer drug-fibrin clot" for regional cancer chemotherapy. Anticancer drugs used in the present study were ADM, MMC, MTX, 5-FU and cDDP. The release of drugs from fibrin clots was studied in vitro. Each fibrin clot was intraperitoneally administered to cancer (AH-130)-bearing rats to evaluate the oncolytic effects. The activities of anticancer drugs delivered from the clots were maintained for more than two weeks. Survival terms of cancer bearing rats were remarkably prolonged with the anticancer drug-fibrin clots. Neither recurrence of ascites nor metastases of malignant cells was observed in the rats treated with such clots. Our newly devised anticancer drug-fibrin clots showed a sustained release of oncolytic drugs and favorable antineoplastic effects. This newly devised drug delivery system suggested a clinical potential for regional cancer chemotherapy.

Bio-adhesio-chemo (BAC) therapy for patients with malignant pleural effusion.

Eighteen patients with serious pleuritis carcinomatosa with remarkable pleural effusion were treated with a new pleurodesic therapy, and all the patients treated obtained favorable results. After removing pleural effusion, fibrinogen solution was intrapleurally instilled and then, our newly devised material, G.T.XIII and an anticancer drug, Adriamycin (ADM), were administered as chemosclerosing agents in an attempt to prevent recurrence of the effusion and also to provide locoregional antineoplastic effects. Recurrence of pleural effusion was nil in all patients treated, and subjective complaints of the patients were remarkably relieved. There were 14 patients evaluable, and all the response of these patients resulted in partial response (PR) according to the World Health Organization (WHO) criteria. Improvement of performance status (PS) was observed in 61% (11/18). Eight patients could be discharged. Three patients have remained alive. Fifteen patients died after the therapy, and their median survival was 67 days. Eight patients were autopsied. The postmortem examinations confirmed that fibrous adhesion in the pleural cavity with these materials was significant, and evidence of recurrence of pleural fluid was not seen. Topical oncolytic effects of the ADM were histologically remarkable. This pleurodesis was called "Bio-adhesio-chemo (BAC) therapy."

[A comparative study of preoperative intra-arterial infusion chemotherapy and transcatheter arterial chemo-embolization in patients with locally advanced breast cancer].

A Comparative study of preoperative intra-arterial infusion chemotherapy (I.A.) and transcatheter arterial chemo-embolization (TAC-E) was carried out on thirty-eight patients with locally advanced breast cancer. The results were as follows. (1) In the primary lesions, there was no difference in response rate between these two treatment modalities. (2) As for side effects, moderate myelosuppression and gastrointestinal disorders were frequently observed in I.A. group. (3) Considerably lower recurrence rate of visceral metastasis was noted in I.A. group, in comparison with the TAC-E group. After TAC-E, however, there was no local recurrence. (4) Five-year cumulative survival rate of I.A. and TAC-E group were 52.3% and 60.7% respectively, without any significant difference between the two groups. These results indicated that both I.A. and TAC-E were effective preoperative treatment for locally advanced breast cancer. Therefore, we should select each treatment modality considering the patient's characteristics.

[A newly devised chemo-embolic agent, G. T. XIII-ADM].

In order to bring about ideal chemotherapy, targeting, topical maintenance, sustained release and no side effects of the anticancer agent are essential. Adriamycin (ADM) was immobilized on absorbable gelatin material (G) together with thrombin (T) and factor XIII (XIII) to form such an agent, "G . T . XIII-ADM". The material was applied as an embolic agent in experimental transcatheter arterial chemo-embolization (TACE) in rabbits with VX2-carcinoma. Response rate of the tumor (CR + PR) was 75% for "G . T . XIII-ADM", and 28.6% for intra-arterial infusion (IA) of ADM. The ADM was maintained for a long period both in the tumors and the metastatic lymph nodes, in the animals given the chemo-embolic agent. The materials were then clinically prescribed as an embolic agent in preoperative TACE for patients with locally advanced breast cancer. The oncolytic effects obtained with the "G . T . XIII-ADM" were remarkably favorable and the side effects were almost nil. These positive data suggest that "G . T . XIII-ADM" has great potential as a new approach to cancer chemotherapy.

Combined transcatheter arterial embolization and regional chemotherapy for locally advanced carcinoma of the breast. A preliminary investigation.

Seventeen patients with carcinoma of the breast received a combination of transcatheter arterial embolization and regional chemotherapy before surgery. A gelatin powder mixed with an anticancer agent and blood clotting factors (own technique) was selectively injected into the internal mammary artery, the lateral thoracic artery, and the thoracodorsal artery. Marked regression of both primary tumor and metastatic regional lymph nodes was observed. The potential of this method as presurgical treatment is discussed.

[Intra-arterial infusion chemotherapy and transcatheter arterial chemo-embolization for patients with simultaneous bilateral breast cancer].

We have treated 2 cases of simultaneous bilateral breast cancer by intra-arterial infusion chemotherapy (IA) and transcatheter arterial chemo-embolization (TAC-E), respectively. In the former case treated by I. A., both the treated tumor and the contralateral mass were remarkably regressed and necrotized. However, serious systemic side effects due to the intraarterially infused drug were observed. In the latter case treated by TAC-E, chemo-embolic effects were selectively observed in the treated tumor, and side effects were slight. On the other hand, a non-treated mass showed no changes. From these findings, we concluded that I. A. serves as a semisystemic therapy, and that TAC-E, at least in our subjects, works as a loco-regional cancer chemotherapy.