Final answer:
E-cadherin mutations (CDH-1) are commonly associated with an increased risk of diffuse gastric cancer and lobular breast cancer, not squamous cell carcinoma.
Step-by-step explanation:
E-cadherin mutations (CDH-1) are most notably associated with a heightened risk for developing diffuse gastric cancer and lobular breast cancer. E-cadherin is a molecule involved in cell adhesion; more specifically, it is a key component of adherens junctions that facilitate cells sticking together to form tissue structures. When these dependent cadherins are mutated, it can disrupt cell adhesion, which is an important aspect in carcinogenesis. In contrast, squamous cell carcinoma—a common type of skin cancer that primarily affects the squamous cells in the epidermis—is not commonly linked to CDH-1 mutations. Instead, squamous cell carcinoma is more frequently associated with factors like UV exposure and human papillomavirus (HPV) infections.