[Intraarterial chemoembolization therapy for unresectable liver cancer using plachitin particles]

Plachitin formed of both poly-N-acetyl-D-glucosamine (chitin) and cis-diamminedichloroplatinum (CDDP), was used as an arterial chemoembolization therapy against unresectable liver cancer. One gram of Plachitin contained 300 mg of CDDP. The Plachitin particle was 50-100 microns in diameter. Plachitin particles (50-100 mg) were injected via hepatic artery once or twice every week, and the total amount of 300 mg was considered one course of this therapy. The size and number of tumors were measured by computer tomography (CT). Pharmacokinetics of this drug was also assessed by serum and urine platinum (Pt) concentration. Three patients underwent the chemoembolization therapy using plachitin particles. Case 1 had multiple hepatocellular carcinomas. The tumor regression rate was 39% after two courses of this therapy. Serum alpha-fetoprotein (AFP) level decreased from 1,182 ng/ml to 300 ng/ml. Case 2 suffered from bile duct cystadenocarcinoma. After three courses of the therapy, the tumor regression rate was 84.4%. Serum carbohydrate antigen 19-9 (CA19-9) decreased from 731 U/ml to 75 U/ml. Case 3 had synchronous multiple liver metastases from sigmoid colon cancer. The tumor regression rate was 77% after one course of the therapy. Carcinoembryonic antigen (CEA) and CA19-9 decreased from 406 ng/ml to 65 ng/ml and from 4,800 U/ml to 790 ng/ml, respectively. The response rate of the 3 cases was 66.7%. The peak levels of the serum Pt concentration of three patients were 0-0.4 microgram/g throughout the therapy, but peak urine Pt concentrations were observed during one course of the therapy of three patients ranging from 0.5 microgram/g to 3.2 micrograms/g, and decreased gradually for three weeks after the first course. Adverse effects of Plachitin particles for arterial chemoembolization were epigastralgia, nausea, fever, and elevation of serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels. These adverse effects were observed in all patients, but were transient. Catheter obstruction occurred in one patient (case 2). Cholecystitis, pancreatic pseudocyst, and duodenal ulcer were noticed in case 3. No renal hypofunction was observed. Plachitin might be a useful agent for arterial chemoembolization therapy for primary and secondary liver cancer.