This study determines microbial diversity between inflamed and non-inflamed skin of patients with immune checkpoint inhibitor-induced dermatitis. Skin has millions of bacteria. When treated with an immunotherapy agent, skin issues like a rash are common, occurring in up to 45% of patients. This study finds out if the type of bacteria on skin is different between the affected and unaffected skin in patients who have this treatment-related rash and also compares the immune cells found in the skin tissue to those seen in the blood.

PRIMARY OBJECTIVE:

I. To determine if skin microbial diversity (estimated by the Shannon Index) significantly differs between inflamed and non-inflamed skin from patients who have immune checkpoint inhibitor (ICI)-induced dermatitis.

SECONDARY OBJECTIVES:

I. To investigate if certain bacterial species and strains are present in higher concentrations of inflamed versus non-inflamed skin of patients with ICI-induced dermatitis.

II. To compare the immune cell phenotypes of inflamed and non-inflamed skin from patients who have ICI-induced dermatitis.

III. To characterize the immune cell phenotype in the peripheral blood in patients who have ICI-induced dermatitis.

IV. To elucidate any association between the skin microbial diversity and response to immunotherapy, characterized by Response Evaluation Criteria in Solid Tumors (RECIST) criteria (e.g., durable complete response [CR] versus partial response [PR] versus stable disease [SD] versus primary progressive disease).

V. To ascertain if higher concentrations of certain bacterial species are associated with a response to immunotherapy, characterized by both RECIST and immune response criteria.

VI. To evaluate associations between the non-inflamed skin flora and cancer subtypes (e.g., renal cell carcinoma, bladder cancer, lung cancer).

VII. To examine if skin microbiome is associated with specific demographic characteristics such as age and gender.

OUTLINE:

Patients undergo punch biopsies of inflamed and non-inflamed skin and a blood sample collection.

Inclusion Criteria:

• Patients receiving treatment with any of the Food and Drug Administration (FDA) approved monoclonal antibodies that block CTLA-4, PD-1, PD-L1, or any combination thereof
• Patients recommended to undergo skin biopsy due to a clinical diagnosis of ICI-induced dermatitis as part of routine and standard clinical care are eligible
• Patients must be age 18 or older
• Eastern Cooperative Oncology Group (ECOG) performance status < 2
• Measurable disease as per RECIST 1.1
• Patients must be able to personally sign and date informed consent indicating that the patient has been informed of all pertinent aspects of the study are eligible

Exclusion Criteria:

• Patients taking antibiotics or who plan to begin taking antibiotics
• Use of topical or systemic steroids within the past 14 days. Inhaled steroids are permitted
• Known medical condition (e.g. a disease associated with chronic skin inflammation such as atopic dermatitis or psoriasis) that, in the investigator's opinion, would increase the risk associated with study participation or interfere with the interpretation of results
• Not recovered to non-dermatologic =< grade 1 toxicities related to any prior therapy
• Pregnant woman will not be enrolled in this study. It is a regulatory requirement that for studies that carry no prospect of benefit to the woman, the research can only enroll pregnant women if the resulting knowledge cannot be obtained by any other means. In this study, there is no prospect of direct benefit to the pregnant women
• Patients with human immunodeficiency virus (HIV), hepatitis B, or C will be excluded from this study
• Any other condition that would, in the Investigator's judgment, contraindicate the patient's participation in the clinical study due to safety concerns or compliance with clinical study procedures (including compliance issues related to feasibility/logistics)