The investigators propose to ensure a favorable gut microbiome by fecal microbiota transplant to enhance the efficacy Keytruda

Studies have shown that a favorable microbiome can be the difference between response and non-response of certain cancer treatments such as PD-1 blockade inhibitors. As such the investigators propose to ensure a favorable microbiome in this patient by fecal microbiota transplant to enhance the efficacy of such a drug, Keytruda.

Inclusion Criteria:

• Patient with metastatic mesothelioma deemed a candidate for PD-1 blockade inhibitor therapy

Exclusion Criteria:

• Patient unable/unwilling to comply with protocol
• Patient deemed not a candidate for PD-1 Blockade inhibitor therapy