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Theoretically yes. But I would say not about sadism, but about unmanifested aggression. Aggression goes to the outside, or inside. The aggression on oneself causes autoimmune diseases and oncology. Awareness of their aggression and "releasing" it fits the state. Whether it can cure oncology depends on the stage. The manifestation of sadism to the outside world (people, animals) will entail consequences that may be worse than oncology. But aggression can be released on inanimate objects - boxing, for example - a pear. Or beat a pillow. Or stick on the asphalt. After such exercises, there is always relief and relaxation. Only need to do it seriously.