Tumorigenicity of poly-L-lactide (PLLA) plates compared with medical-grade polyethylene

✍ Scribed by Nakamura, Tatsuo ;Shimizu, Yasuhiko ;Okumura, Norihito ;Matsui, Teruo ;Hyon, Suong-Hyu ;Shimamoto, Takeshi

• Book ID: 102874238
• Publisher: John Wiley and Sons
• Year: 1994
• Tongue: English
• Weight: 957 KB
• Volume: 28
• Category: Article
• ISSN: 0021-9304
• DOI: 10.1002/jbm.820280104

✦ Synopsis

Poly-L-lactide (PLLA) plates, 20 X 10 X 1 mm in size, with flat surfaces, were implanted into 50 young male Wistar rats subcutaneously, and the incidence of tumors for 2 years under specific pathogen-free (SPF) conditions was evaluated. Tumors arose in 22 rats (at the implant sites in 20, and distant from the implantation site in 2). As a control, plates of medical-grade polyethylene of the same shape were implanted into 50 rats. Tumors appeared in 23 of these rats (21 at the sites of the plates, and 2 ectopically). In 30 rats given sham operations, no tumors appeared in the 2 year observation period. Histologically, all the tumors were mesenchymal malignant tumors resembling fibrosarcoma or malignant fibrous histocytoma (MFH) in humans. In 6 of the PLLA tumors and 3 of the PE tumors, bone formation was observed. There was no significant difference between the incidence of tumors caused by PLLA plates and that of tumors caused by medical-grade polyethylene plates. Macroscopically, PLLA plates retained their initial shape for 2 years. Scanning electron microscopy revealed small holes on the surfaces of the plates, and their molecular weight was reduced to 8% of the initial value.