Neoadjuvant interferon alfa-2b treatment in a murine model for metastatic ocular melanoma - A preliminary study

Objectives: To investigate the treatment of metastasis from uveal melanoma and to test the effect of interferon (IFN) alfa-2b in a murine model. Methods: The B16-LS9 tissue culture melanoma cells were inoculated into the posterior intraocular compartment of 3 groups of C57BL/6 mice. The inoculated eyes were enucleated at 9 days and the mice were euthanized at 26 days after inoculation; the site and number of metastases were determined using standard histologic techniques. Group 1 was the control group; group 2 was given 20 000 international units (IU) of IFN alfa-2b intramuscularly 12 hours before enucleation, and group 3 received daily injections of 20 000 IU of IFN alfa-2b intramuscularly starting 4 days before enucleation. Results: Pulmonary metastases were detected in 57%, 33%, and 0% of groups 1, 2, and 3, respectively; hepatic micrometastases were detected only in group 1. These results showed a significant decrease in hepatic metastases in mice receiving IFN alfa-2b vs controls (P=.005). Conclusion: Treatment with IFN alfa-2b results in decreased hepatic metastases from intraocular melanoma in a murine model.