[A study of concentrations of CDDP in blood and cancer tissues in CDDP-treated gastrointestinal cancer].

Cisplatin (CDDP) was administered by intravenous drip in 3 cases of gastrointestinal cancer, and by intraperitoneal spraying in 2 other similar cases; and free CDDP and total CDDP levels in blood were determined with time. In the former cases, the free CDDP level rose from 30 minutes after the start of intravenous drip, to reach a peak at 2 approximately 4 hours after the end of the drip, while it was undetectable at 24 hours. The total CDDP level reached a peak 4 hours after the start of the drip, and then gradually decreased at 24, 48, 72 and 96 hours, although it still remained detectable in blood. In the latter cases, free CDDP appeared in blood at 15 minutes after the spraying, and disappeared from blood in 30 minutes to 1 hour. The total CDDP level reached a peak at 30 minutes, and then decreased in a manner similar to that seen in cases given the intravenous drip. CDDP levels in resected stomachs, resected colon and dissected lymph nodes following intravenous drip of CDDP were then measured in 4 cases of stomach cancer and another of cancer of the descending colon. There was no significant difference in CDDP level between cancer tissues, non-cancer tissues and lymph nodes. It thus appears that CDDP is taken up equally by normal tissues and cancer tissues, and that it may be necessary to study the metabolic pathways of CDDP after it has been taken up by the tissues.