Radioimmunotherapy prevents local recurrence of colonic cancer in an experimental model.
BACKGROUND
Radioimmunotherapy (RIT) is suitable for the treatment of microscopic residual disease and might therefore have an adjuvant role after colonic cancer surgery.


METHODS
An anastomosis was constructed in male Wag/Rij rats after intraluminal injection of 2 x 10(6) CC531 tumour cells. The biodistribution of (111)In-labelled MG1 monoclonal antibody was assessed after intraperitoneal administration. The therapeutic efficacy of (177)Lu-labelled MG1 (74 MBq per rat), administered on the day of surgery (D0, n = 13) or 5 days later (D5, n = 13), was compared with that of carrier only (n = 13). The primary endpoint was perianastomotic tumour growth 28 days after surgery.


RESULTS
(111)In-labelled MG1 preferentially accumulated in perianastomotic CC531 tumours. RIT resulted in a transient reduction in bodyweight in both treatment groups compared with controls, but there were no other signs of clinical discomfort. No macroscopic or microscopic perianastomotic tumour growth was found in eight of 11 animals in the D0 group and 11 of 13 in the D5 group, whereas 11 of 13 controls had macroscopic tumour (P = 0.011 and P = 0.001 respectively).


CONCLUSIONS
This study suggests that RIT may be an effective adjuvant treatment for preventing local recurrence after resection of colonic cancer.
de Jong
G M
GM
Department of Surgery, Division of Oncology and Abdominal Surgery, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands. g.dejong@chir.umcn.nl
Boerman
O C
OC
Heskamp
S
S
Aarts
F
F
Bleichrodt
R P
RP
Hendriks
T
T
D000818:Animals; D000911:Antibodies, Monoclonal / Q000493:pharmacokinetics / Q000627:therapeutic use; D001835:Body Weight; D045744:Cell Line, Tumor; D003110:Colonic Neoplasms / Q000473:pathology / Q000517:prevention & control*; D008187:Lutetium / Q000493:pharmacokinetics / Q000627:therapeutic use; D008297:Male; D009364:Neoplasm Recurrence, Local / Q000473:pathology / Q000517:prevention & control*; D009368:Neoplasm Transplantation; D004369:Pentetic Acid / Q000493:pharmacokinetics / Q000627:therapeutic use; D016499:Radioimmunotherapy; D011868:Radioisotopes / Q000493:pharmacokinetics / Q000627:therapeutic use; D051381:Rats; D047368:Tumor Burden
D000911:Antibodies, Monoclonal; D011868:Radioisotopes; D008187:Lutetium; D004369:Pentetic Acid