Antimetastatic effect of a stable prostacyclin analogue (PGI2-TEI8153) in combination use with adriamycin (ADM) was investigated. Meth A cell, which had membrane protein of 18,000 daltons specifically bound to platelets, induced platelet aggregation dose-dependently. This platelet aggregation was totally suppressed by PGI2-TEI8153. PGI2-TEI8153 also suppressed the pulmonary arrest as well as pulmonary metastasis of Meth A cells. Combined use of PGI2-TEI8153 and ADM exerted much less antimetastatic effect than that with PGI2-TEI8153 alone, indicating the counteracting effect of ADM against the PGI2-TEI8153. However, this combination use brought about additive antimetastatic effects with 2-fold reduction of pulmonary nodules compared to that of ADM alone. Consequently, even the anticancer drug itself has a negative influence on metastasis, the combined use of PGI2-TEI8153 with it is promising for the prevention of metastasis.