[Possibility of alpha-tricalcium phosphate (alpha-TCP) particles as a drug carrier for treatment of abdominal carcinomatosis].
It is reported that cancer foci are unevenly distributed in abdominal carcinomatosis after intraperitoneal inoculation of cancer cells in rats. The organs may be briefly classified into two groups in terms of the deposit of cancer cells: one that shows an affinity to the cells includes the greater omentum, mesenterium, and gonadal fat and etc., and the other having lesser affinity the stomach, intestine, and spleen and etc. Such uneven distributions are likely to occur in clinical cases of abdominal carcinomatosis resulting from progressive digestive cancers. We have explored the possibility of alpha-Tricalcium Phosphate (alpha-TCP) particles as a drug carrier in which carboplatin (CBDCA) was incorporated. alpha-TCP, which has chemically similar properties to hydroxyapatite, is known to have an excellent biocompatibility with human tissues and is biodegradable. The present study focused on the localization and the forms of alpha-TCP particles, and the morphological changes of the surrounding tissues after intraperitoneal administration using normal and cancer-bearing rats. The following results were obtained: (1) alpha-TCP particles were taken up to a large extent in the "milky spot" of the greater omentum, followed by the "stomata" of the mesenterium, gonadal fat, diaphragm, peritoneum, and liver in normal rats. No alpha-TCP particles were caught up in the tissues of the stomach, small intestine, colon, and spleen. The margination and emigration of lymphocytes were slightly observed around those organs. (2) alpha-TCP particles were predominantly detected on the cancer mass of the greater omentum in abdominal carcinomatosis-bearing rats. It should be noted that the particles collected in the same place where cancer cells were caught, suggesting that the localization of the drug-containing particles result in higher drug concentrations in the cells possibly for extended times. The alpha-TCP particles system is expected to be a good candidate for targeting chemotherapy and specially for abdominal carcinomatosis.
Ueda
T
T
First Dept. of Surgery, Medical School, Nagoya City University.
Mizuno
I
I
Yotsuyanagi
T
T
Akamo
Y
Y
Mohri
N
N
Terada
J
J
Shibata
T
T
Yamamoto
T
T
Takeyama
H
H
Manabe
T
T
D000008:Abdominal Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D000818:Animals; D000970:Antineoplastic Agents / Q000008:administration & dosage*; D002130:Calcium Phosphates / Q000493:pharmacokinetics; D016190:Carboplatin / Q000008:administration & dosage*; D004337:Drug Carriers; D006801:Humans; D007263:Infusions, Parenteral; D008114:Liver Neoplasms, Experimental / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology; D008297:Male; D051381:Rats
D000970:Antineoplastic Agents; D002130:Calcium Phosphates; D004337:Drug Carriers; C485828:alpha-tricalcium phosphate; C485830:tetracalcium phosphate; C485838:calcium phosphate, monobasic, anhydrous; C020243:calcium phosphate; D016190:Carboplatin; C485829:calcium phosphate, dibasic, anhydrous