OBJECTIVETo establish mouse models that mimic the postoperative carcinoma metastasis in human, and observe the difference in the biological characteristics between the models for different human carcinomas.

METHODSGBC, HCT-116, NCI-H460 and SMMC-7721 cells were inoculated subcutaneously in nude mice, respectively, and when the diameter of the resulting tumors reached 1.5 cm, tumor-reductive surgery (TRS) was performed, and the survival and tumor metastasis in the mice were observed.

RESULTSTumor metastasis in the lungs occurred in 6 nude mice (75%) in GBC group at 10 weeks postoperatively, while no tumor metastasis was found in the control group at 8 weeks, and the survival time of post-TRS mice was 2 weeks longer than that in mice without TRS. In HCT-116 group, the number of nude mice with metastasis in the lungs, spleen, and lymph nodes was 15 (100%), 5 (33.3%), and 15 (100%) 17 weeks after TRS, respectively, while only 3 (23.1%) mice in the control group developed lung metastasis at 9 weeks, and the survival time of the mice showed a 8-week prolongation after TRS. In NCI-H460 group, lung metastasis occurred in 5 nude mice (100%) 14 weeks after TRS, while no metastasis was found in the control group at 10 weeks, and TRS resulted in a 4-week prolongation of the survival time of the mice. In SMMC-7721 group, no metastasis occurred in IRS or control group in spite of the presence of organ failure, and the survival time of the mice was prolonged by 6 weeks after TRS.

CONCLUSIONSResection of subcutaneously implanted tumor allows greater chances for postoperative metastasis but prolongs the survival of the tumor-bearing nude mice. The likeliness of postoperative metastasis is related to the biological characteristics of the original tumor implanted.