What is a common cancer type seen in CMMRD?

The presence of small bowel cancer is commonly associated with Constitutional Mismatch Repair Deficiency (CMMRD), which is a genetic disorder caused by mutations in mismatch repair genes such as MLH1, MSH2, MSH6, and PMS2. Individuals with CMMRD have an increased risk of developing various types of cancers, particularly childhood cancers like gliomas and hematologic malignancies, as well as colorectal cancers and small bowel cancers.

Small bowel cancer is particularly significant in CMMRD patients; studies and clinical observations highlight this relationship. The mechanism behind CMMRD involves a failure in DNA repair, leading to the accumulation of mutations that can result in cancerous changes, particularly in tissues such as the small intestine that are actively dividing.

Other cancer types listed, such as breast cancer, adrenal cancer, and thyroid cancer, while they may have associations with other genetic syndromes or population risk factors, are not as specifically linked to CMMRD as small bowel cancer is. Thus, understanding the unique cancer risk profile associated with CMMRD is essential for appropriate screening and management of affected individuals.