- A formalin fixed, paraffin-embedded (FFPE) tumor tissue block or a minimum of 3 unstained slides of tumor sample obtained via excisional, incisional, or core needle biopsy from a metastatic or loco-regionally recurrent lesion. A new baseline biopsy does not need to be obtained for study purposes. If 3 unstained are unavailable from a metastatic or loco-regionally recurrent lesion, with permission of the PI, FFPE tumor tissue from the primary disease site at the time of original diagnosis is acceptable.