Gut Microbiome in Fecal Samples From Patients With Metastatic Cancer Undergoing Chemotherapy or Immunotherapy

PRIMARY OBJECTIVES:

I. To quantitatively determine the composition of the microflora and their gene and protein
expression levels in patients with metastatic colorectal cancer being treated with
fluorouracil (5-FU) based chemotherapy, or anti-PD1 immunotherapy.

SECONDARY OBJECTIVES:

I. Compare the changes in species composition and in the metabolic activities (as determined
in the primary objective) with response to chemotherapy or immunotherapy.

II. Compare the changes in species composition and in the metabolic activities (as determined
in the primary objective) with toxicities and side effects resulting with chemotherapy or
immunotherapy.

OUTLINE:

Patients undergo collection of fecal specimens at baseline, prior to start of each course of
chemotherapy or immunotherapy, at the end of weeks 2, 4, 6, and 8, at the end of course 3 and
courses thereafter of chemotherapy or immunotherapy, and at the time of disease progression
or going off-treatment. Fecal specimens are analyzed via 16S ribosomal ribonucleic acid (RNA)
gene sequencing, meta-transcriptomics analysis, and meta-proteomics analysis.

Inclusion Criteria:

- Must be willing and able to provide fecal samples according to protocol schedule

- COHORT A

- Diagnosis of metastatic colorectal cancer, where the metastatic disease has not been
previously treated

- Scheduled to begin fluorouracil/leucovorin calcium/oxaliplatin (FOLFOX) or folinic
acid-fluorouracil-irinotecan (FOLFIRI) based chemotherapy for the advanced disease

- Must have radiologic evidence of disease

- COHORT B

- Diagnosis of metastatic cancer

- Scheduled to begin pembrolizumab or another anti-PD-1 or anti-PD-L1 antibody as single
agent therapy for the treatment of the advanced disease

- Must have physical or radiologic evidence of disease

Exclusion Criteria:

- Patients with a colostomy or any other issues that may prevent the standard methods
for collection of stool are not eligible for this study

- Patients are not enrolled or a research protocol for treatment