Estimating Lymphocyte Counts from DNA Methylation

Assessment of DNA Methylation Signatures in Lymphocytes for Evaluating the Efficacy and Prognosis of Immunotherapy in Colorectal Cancer

The goal of this observational study is to assess lymphocyte levels in colorectal cancer patients using DNA methylation levels in tissues or blood. The main questions it aims to answer are:

Can DNA methylation features calculate lymphocyte levels? Can the calculated lymphocyte levels assess the efficacy and prognosis of immunotherapy?

Inclusion Criteria:

1. Diagnosed with colorectal cancer by colonoscopy pathology and deemed eligible for immunotherapy after assessment.
2. Neoadjuvant immunotherapy regimen includes PD-1 or anti-PD-L1.
3. R0 resection is performed after neoadjuvant immunotherapy.
4. Complete immunotherapy efficacy assessment data and follow-up data are available.
5. The tissue bank stores the required whole blood and tissue samples for the experiment.

Exclusion Criteria:

1. Concurrent other malignancies.
2. Neoadjuvant immunotherapy not conducted according to the standard protocol.
3. Severe adverse chemotherapy reactions that lead to the discontinuation of immunotherapy midway.
4. Lack of complete neoadjuvant chemotherapy efficacy assessment data or follow-up data.
5. The tissue bank does not store the required whole blood or tissue samples for the experiment.
6. Patients with concurrent other immune system diseases.