A doctor will examine the lump and may feel the wrist and hand to see whether it is connected to a joint or tendon.
If it is a skin cyst, the area is numbed and opened, the contents are drained and the sac is removed so it is less likely to come back.
The spot is then cleaned and bandaged, and keeping it clean and protected helps older skin heal well.
Moisturizing dry skin, protecting the arms from bumps and scrapes and not picking at lumps all help prevent problems.
Age is just a number, so take care of yourself at every age. The videos below show cysts being treated by professionals.