What constitutes material information in medical malpractice cases?

"Material information is that which the physician knows or should know would be regarded as significant by a reasonable person in the patient's position when deciding to accept or reject the recommended medical procedure. (Citations.) To be material, a fact must also be one which is not commonly appreciated. (Citation.) If the physician knows or should know of a patient's unique concerns or lack of familiarity [120 Cal.App.3d 441] with medical procedures, this may expand the scope of required disclosure. (Citation.)" (Truman v. Thomas (1980) 27 Cal.3d 285, 291, 165 Cal.Rptr. 308, 611 P.2d 902.)