Adjuvant 131I-anti-CEA-antibody radioimmunotherapy inhibits the development of experimental colonic carcinoma liver metastases
1998 (English)In: Anticancer Research, ISSN 0250-7005, E-ISSN 1791-7530, Vol. 18, no 2A, 843-848 p.Article in journal (Refereed) Published
Adjuvant radioimmunotherapy (RIT) for human colonic cancer was performed in a nude rat model of experimental liver metastases. Thirty-three rats were injected intraportally through a mesenteric vein with 5 x 10(6) cells from the human colonic cancer cell line LS174T. Within half an hour, 20 MBq (n = 2), 75 MBq (n = 5), or 150 MBq (n = 10) of the 131I-labelled anti- carcinoembryonic antigen (CEA) monoclonal antibody (MAb) 38S1 was administered intravenously (i.v.), whereas control groups received either i.v. saline injections (n = 12) or 150 MBq of the irrelevant 131I-labelled MAb 79C (n = 4). Decay corrected whole-body data showed that more than 80% of the initially MAb-bound radioiodine was excreted during the first 2 weeks. Whole- body clearance and blood clearance of 131I-38S1 and 131I-79C were essentially similar. At sacrifice 5-7 weeks after administration, neither 20 MBq nor 75MBq 131I-38S1 significantly prevented the development of liver metastases. By contrast, with 150 MBq, no metastases formed in the animals treated with MAb 131I-38S1 or 131I-79C. A radiation induced effect on the haematopoietic system was found in the 150MBq dosage groups. It is concluded that the inhibition of tumour induction was not strictly dependent on a radiation dose delivered by a tumour-specific MAb. Since a non-tumour-specific 131I-MAb, in a smaller group of animals, proved equally efficacious in preventing tumour growth, the total body 131I dose was probably the major contributing factor.
Place, publisher, year, edition, pages
1998. Vol. 18, no 2A, 843-848 p.
IdentifiersURN: urn:nbn:se:uu:diva-231370PubMedID: 9615730OAI: oai:DiVA.org:uu-231370DiVA: diva2:744409