I cut mine back a few times....especially when it started losing its leaves on the lower part of the stem. It was looking 'leggy'. I just cut it back like pruning a rose
, 45* cut at a leaf node. I have also cut whole stems right to the base with no troubles.
Your plant looks nice and healthy. It might be that in time you will need to repot it in a larger pot....if you want to keep it that size.