This study explores the role of T cells in monitoring disease status and response during anti-PD-1/PD-L1 treatment in patients with melanoma, lung and other cancer types. Measuring levels of specific targets such as Bim and soluble PD-L1 during therapy may help track treatment resistance and clinical outcomes. This information may also help researchers determine why some people with melanoma, lung and other cancer types respond to PD-1/PD-L1 treatment and others do not.

PRIMARY OBJECTIVES:

I. Establish the role of Bim for monitoring disease status during anti-PD-1 therapy.

II. Identify the mechanisms of resistance to anti-PD-1 blockade. III. Quantify and modulate levels of NKG7 messenger ribonucleic acid (mRNA) in CD8+ T cells.

OUTLINE: This is an observational study.

Patients undergo blood sample collection throughout the study. Patients also undergo optional stool sample collection and have their medical records reviewed on study. In addition, patients provide previously-collected tissue sample, if available.

Inclusion Criteria:

• Are 18 years of age or older
• Have histologic evidence of locally or regionally advanced or stage IV malignancy
• Are considered appropriate for starting therapy with anti-PD-1/anti-PD-L1 monoclonal antibody by their treating physician (prior therapy with immune checkpoint inhibitor (ICI) is allowed)
• Have an understanding of the protocol and its requirements, risks, and discomforts
• Are willing to undergo peripheral blood collection at the time points mentioned in the protocol
• Are able and willing to sign an informed consent

Exclusion Criteria:

• Inability on the part of the patient to understand the informed consent or be compliant with the protocol
• Patients receiving any concurrent anti-cancer therapy or investigational agents (with the exception of an anti-PD-1/anti-PD-L1 agent as mentioned above)
• Patients who are pregnant, nursing, or are of childbearing potential and are unwilling to employ adequate contraception

Patients with metastatic melanoma, lung or other cancer recruited from the clinical practice in the Department of Oncology at Mayo Clinic in Rochester, Minnesota who are considered appropriate for starting therapy with an open-label commercially available, FDA approved anti-PD-1 monoclonal antibody by their treating provider.