Rabbit model of uveal Greene melanoma: morphologic studies of metastatic lesions.

We studied the morphology of metastatic tumors in three rabbits with implanted choroidal Greene melanoma. The tumor-bearing eyes were perforated and destroyed by the expanding tumors 10 to 12 weeks after implantation. The animals then lost body weight and became cachectic; they were suspected of having metastases and were sacrificed. The interval between the destruction of the eye and the discovery of metastases was 1 to 14 weeks. Widespread metastases involved the liver, lungs, kidneys, and subcutaneous tissue, with the greatest number of tumors in the liver and lungs. Histopathologic findings in the metastases and primary tumors were identical. This model may be considered appropriate for study of human uveal melanoma because (1) the biological behavior is similar to that of human uveal melanoma, (2) the primary and metastatic tumors are histologically similar, and (3) the large size of the rabbit's eye facilitates observation and manipulation.