Advanced stages of cancer are generally weaker, and can cause night sweats as well as drowsiness. Night sweats, i.e. abnormal sweating after going to sleep, are often more pronounced late at night and before dawn. Weakness and fatigue and profuse sweating are more common in advanced cancer. Drowsiness, i.e. excessive prolongation of the sleep state, is characterized by fatigue, weakness, slow reaction, and lack of spirit upon awakening. The increase of cancer cells in the body in the advanced stage of cancer will also be transferred to the brain, consuming nutrients and sugar in the body, thus leading to a lack of nutrients in the body and a lack of energy substances, producing drowsiness symptoms. There are also cases where the body is weakened due to long-term medication, resulting in drowsiness. If you have a tumor and suffer from night sweats, drowsiness, fatigue, etc., you should have a review at any time in order to avoid deterioration of your condition.