Colorectal cancers are the third most common type of cancer in the world. Peritoneal carcinomatosis and intraabdominal acid development occur in advanced stages of colorectal cancers.

It is known that the immune system plays an important role in tumor development or tumor eradication. Differentiation of T cells towards Th2 and regulatory T cells is also reported to be effective in tumor progression.

Among the mechanisms of escape from the immune system, changes in the tumor microenvironment play an important role. The role of regulatory T lymphocytes, a subgroup of T cells that play a regulatory role by suppressing the function of other T lymphocytes, is to reduce the chronic immune response against viruses, tumors and patients's own antigens. The common feature of all Tregs is that they secrete one or more anti-inflammatory molecules such as IL-10, TGFβ or IL-35. High levels of Tregs have been found in peripheral blood, tumor tissue and lymph nodes in patients with malignancy.

In our study, it is aimed to evaluate whether there is a difference in intraabdominal ascites fluid T helper cytokine levels in patients with end-stage colorectal cancers compared to patients without malignancy.

Colorectal cancers are the third most common type of cancer in the world. Peritoneal carcinomatosis and intraabdominal ascites development occur in advanced stages of colorectal cancers.

It is known that the immune system plays an important role in tumor development or tumor eradication. Differentiation of T cells towards Th2 and regulatory T cells is also reported to be effective in tumor progression.

Among the mechanisms of escape from the immune system, changes in the tumor microenvironment play an important role. The role of regulatory T lymphocytes, a subgroup of T cells that play a regulatory role by suppressing the function of other T lymphocytes, is to reduce the chronic immune response against viruses, tumors and patient's own antigens. The common feature of all Tregs is that they secrete one or more anti-inflammatory molecules such as IL-10, TGFβ or IL-35. High levels of Tregs have been found in peripheral blood, tumor tissue and lymph nodes in patients with malignancy.

The role of the immune system in colorectal cancers has been demonstrated with the effects of tumor-infiltrating lymphocytes (TIL) and immune control points on TILs or immune control point ligands on patient survival, especially in recent studies. Studies in the literature usually include immunological examinations of patient blood or tumor tissue.

There are many publications in the literature evaluating immunological markers from ascites fluid samples for various reasons. In these studies, T and B cell subtypes were examined from ascites fluid samples taken from patients with ascites, especially ovarian cancer and liver cirrhosis. In the only study on gastrointestinal cancers, immunophenotyping was performed in intraabdominal ascites and blood in 22 advanced gastrointestinal tumor patients and some cell subgroups were associated with worse clinical outcome. In the literature, there is no study on cytokine analysis from intra-abdominal ascites fluids specific to colorectal cancer.

In our study, it is aimed to evaluate whether there is a difference in intraabdominal ascites fluid cytokine level in patients with end-stage colorectal patients compared to patients without malignancy.

Inclusion Criteria:

• End stage Colorectal Cancer patients

Exclusion Criteria:

• Another synchronous tumor with colorectal cancer
• HIV patients
• Pregnancy

The end stage colorectal cancer patients with intraabdominal ascites will be the case group.

Also congestive heart failure and liver cirrhosis patients with intraabdominal ascites will be the control group