抄録
To obtain the maximal local anticancer effect with minimal systemic side effects, we prepared adriamycin(ADR)-containing poly(L-lactic acid) microspheres(ADR-MS)with an average diameter of 50 μm by the oil in oil emulsion method. An almost zero-order release of ADR from the ADR-MS was achieved in Tris buffer and ADR disappeared from the ADR-MS within 20 days. The treatment of mice bearing P 815 tumor cells with ADR-MS showed a higher survival rate than with free ADR. After the instillation of the ADR-MS into the pleural cavity of patients with pleuritis car-cinomatosa, ADR was detected in serum as well as in the pleural fluid for up to 15 days. Moreover, the amount of drainaged ADR was less than a few % of the administered dose, indicating that almost all the ADR-MS remained in the pleural cavity, ADR being released slowly. Furthermore, systemic side effects were not observed after the administration of the ADR-MS. The cytology of the pleural effusion indicated that the malignant stage became Class I after the instillation of the ADR-MS, inspite of adenocar-cinoma Class V before the treatment. The local administration of the ADR-MS was concluded to yield a maximal anticancer effect with minimal side effects.
