Role of the implantation site on metastatic ability of the murine MBT-2 transitional cell carcinoma.

The influence of implantation site on the metastatic behavior of a murine transitional cell carcinoma line (MBT-2) was examined. MBT-2 cells were injected into one of four anatomic sites; subcutaneously, intramuscularly, intravenously or into the footpad, to evaluate the influence of implantation site on the formation and number of metastases. The MBT-2 cell line produced a low incidence of lung metastases after intravenous injection with a mean of 1.1 lung tumors per mouse. Injection of MBT-2 cells into the footpad or subcutaneously did not produce metastases from the primary tumor. Intramuscular implantation, however, resulted in a sixty percent incidence of metastasis with a mean of 8.2 lung nodules per mouse. This study demonstrated a definite implantation site influence on the metastatic ability of the MBT-2 line.