Is cholesterol of 402 possible?

Yes: Familial hyperlipoprotienemias unfortuately are capable of much higher cholesterol levels.

Yes, Several Causes: Total cholesterol (tc) over 400 is seen patients with severe LDL elevations, as well as in certain high triglyceride settings. In addition to genetic disorders, many other conditions can contribute to tc over 400 include; type ii diabetes, metabolic syndrome, abdominal obesity, high alcohol intake, thyroid abnormalities, chronic kidney disease, lupus, and certain meds (steroids, HIV drugs, etc.).