7a4039fb_us_Back_Problems_and_Red_Flags__Red_flag_sign
[Why we are interested] This can be a sign of cancer.This is a bit trickier because although people with serious back problems do get night pain, lots of people with nothing seriously the matter get it too. A study in the UK examined 213 patients who had night pain, with 90 having pain every night. No serious problem was identified with any of them (see reference 1 below). However, If you have this symptom it is important that you discuss it with your doctor. [Red flag sign] 
Severe night pain
Serious Back Problems and Red Flags
Red flag sign