Brief Summary: This study will collect de-identified tumor samples, with correlated clinical/demographic data and tissue histology, from patients selected or scheduled for pre-treatment tumor biopsy or who have had a recent pre-treatment tumor biopsy. These specimens and clinical data may be used in subsequent studies for the development and validation of a diagnostic test.

Detailed Description: This study will establish a prospective cohort of pre-treatment tumor specimens with correlated de-identified clinical and demographic data and tissue histology from cancer patients who are undergoing treatment with PD-1/PD-L1 inhibitors. Patients who have undergone pre-anti-PD-1/PD-L1-treatment tumor biopsy or who are scheduled for tumor biopsy prior to anti-PD-1/PD-L1 treatment will be enrolled. The study will not require a study-specific tumor biopsy; any biopsies taken prior to treatment as part of standard of care are eligible for this study. Biopsies must not have been taken after immunotherapy treatment began. Participants will be asked to provide their consent for the potential use of their biospecimens in subsequent studies for the development and validation of a diagnostic test.