When the liver enlarges, it is usually caused by inflammation.
There are many causes for the liver to become enlarged such as alcohol consumption, medications toxification, hereditary conditions, biliary duct malformation or obstruction, viral or bacterial hepatitis, fatty liver, mushroom poisoning, lymph blockage, blood flow obstruction, etc.
However, all this...no matter what caused it can cause the cells of the liver to be stressed and then the immune systems will step into help and this causes the inflammation.
You asked if hepatomegaly can be cured?
I would say it can is some circumstances.
Medication taken to remove the inflammation, stopping the cause of the
problem like drinking alcohol or losing weight in some fatty liver disease, or stopping medications that can cause this...would be good. The liver is able to heal. However, if the inflammation isn't caught early enough and some of the cells of the liver die off...then this would form
possibly fibrosis and then scar tissue inside the liver and cause even more inflammation and further death of the liver cells. The doctor can only try to prevent more of the liver cells from dying. The scar tissue that develops blocks the nourishment and oxygen from getting to these other cells, so
then this is not reversible.