Why is the pain from bone cancer greater at night?

I do not have an MD, I do hope to be an oncologist one day though. psychology is a part of having cancer, however there is a medical explanation. metastasis(reproduction and spreading) of cancer cells requires glucose which comes from food you eat. throughout the day you are active by walking, talking, etc and the glucose in your body is used for those activities. when you are laying in bed at night all the glucose is being used up be the cancer cells in order to reproduce, and the pain from bone cancer comes from the reproduction of the cancer cells. so laying down=more glucose for the cancer cells, therefore more pain. hope this helps.