Multicausal Psychobiological Interaction Hypothesis

Abstract

Cancer comprises a heterogeneous group of multifactorial diseases that emerge through the accumu lation and selection of cellular alterations within an organism simultaneously influenced by genetic, environmental, metabolic, immune, endocrine, and behavioral factors. The present hypothesis proposes that an individual’s chronic psychological state should not be regarded as a direct or sufficient cause of cancer, but rather as a potentially modulating component within a multicausal psychobiological network. Persistent psychological states - such as chronic stress, prolonged grief, anxiety, social isolation, or sus tained emotional distress - may induce physiological and behavioral changes through neuroendocrine, autonomic nervous, immune, and metabolic systems. These changes may affect variables such as sleep, physical activity, tobacco or alcohol exposure, inflammation, selected immune responses, and other components of homeostasis. The hypothesis proposes that, in individuals with differing levels of genetic susceptibility and under different environmental exposures, these pathways may probabilistically modify the biological context in which a neoplastic process is initiated, selected, or progresses. This hypothesis does not propose that an emotion directly activates a “cancer gene,” nor that a positive psychological state can prevent cancer. Rather, it proposes investi gating whether measurable interactions exist among genetic vulnerability, carcinogenic exposures, psychobiological state, and intermediate mechanisms capable of modifying cancer risk or disease progression.