At this point, it is particularly interesting to recall the earlier reports of middle ear bone remodeling in the gerbil after chemical sympathectomy by guanethidine sulfate (86) or hydroxydopamine (85). Although these neurotoxins do eliminate sympathetic activity, there are, in parallel, major central consequences. In particular, both treatments reduce hypothalamic dopamine, which leads to an increase in serum prolactin levels.
http://ajpendo.physiology.org/content/293/5/E1224.full
"Again, patients admitted with any malignancy, cholecystectomy, thyroidectomy, renal disease, cardiac disease, sympathectomy, or vascular graft were eliminated as controls."
This article reviews the evidence that neuroleptics may increase the risk of breast cancer via their effects on prolactin secretion.
Paul M. Schyve; Francine Smithline; Herbert Y. Meltzer
Neuroleptic-induced Prolactin Level Elevation and Breast Cancer: An Emerging Clinical Issue
Arch Gen Psychiatry, Nov 1978; 35: 1291 - 1301.