- Archival tissue is mandatory (a tumor biopsy- core or excisional) of a metastatic lesion obtained within 1 year prior to study registration (within 4 weeks preferred). Tumor tissue from nephrectomy and site of metastasis will be required. If archival tissue of a metastatic lesion obtained within the preceding year is not available, patients must have at least one site of disease (not including bone metastases) accessible for core needle or excisional biopsy. If archival tissue of a metastatic lesion is not available and biopsy of a new lesion is not feasible, the subject is not eligible for the study.