Dreams often be mysterious and confusing, but they also contain important messages from our subconscious, suggests broken promises.
A possible approach to the interpretation of this dream is that the worm stand as a symbol for something unclean or bad that the dreaming holds in his hand or carries on himself, you need to better get a grip of your inner emotions. Maybe there is a bad habit, an unhealthy relationship or an undesirable behavior that the dreaming is struggling with and that he cannot get rid of, signals longevity, good health or purity. So the worm embody the unpleasant or the toxic that needs to be removed from the your life, symbolises a restoration of your inner harmony.
On the other hand, the worm also indicate the importance of change and renewal, a metaphor for defiance. Worms are often symbols of the decomposition and decay necessary to allow for new growth and life, hints your struggle, determination and ambition. It is possible that the dreaming faces important decisions or changes in his life and that the worm is an indication that he has to let go of old patterns or beliefs to make room for the new, signifies conflict and confrontation.
Independent of the concrete interpretation, a dream of a worm in the hand also be understood as an invitation to deal with the deepest aspects of one's own being and to recognize and accept perhaps hidden fears or shadow aspects, a hint for your own special talents which you have not yet recognized or fully developed.