Cancer neuroscience: The past, the present, and the road ahead.

Both the nervous system and cancer-intrinsic neural features can govern cancer initiation, growth, progression, metastasis, and treatment resistance, while cancer can likewise influence the nervous system, promoting neural reprogramming and neuropsychiatric symptoms that worsen patient outcomes. The field of cancer neuroscience seeks to unravel this complex neuro-cancer crosstalk and holds the promise to develop neuroscience-instructed cancer therapies that improve disease control and quality of life. Here, we summarize the key discoveries of neuro-cancer crosstalk to date, including neuron-to-cancer synapses and paracrine and neuro-immuno-oncological interactions, and then explore emerging topics such as downstream effects on cancer cell pathophysiology, circadian influences, brain-body-cancer communication, and neural regulation of the metastatic cascade and the tumor microenvironment. Finally, we distill overarching principles, highlight relevant ongoing research, and outline conclusions to guide the development of cancer neuroscience, proposing hypotheses for future experimental validation.