Local and systemic architecture surrounding a cancer cell. Includes other cells, growth factors, enzymes, and parts of the blood and lymphatic systems.

a specific set of physical, biological, and cultural factors immediately surrounding the organism.

Surroundings that can be treated as homogeneous or well characterized in the concentrations of an AGENT ( e.g., home, office, automobile, kitchen, store). This term is generally used for estimating inhalation EXPOSURE