You say "islands" therefore I am assuming you mean the Caribbean or the South Seas.
It is not normally known for ships to even overnight in ports in the Caribbean as a rule apart from occasionally at embarkation time. They do stay two days sometimes in the South Seas and the cruises seem to vary each year so for that you would have to look through the brochures or sites like this. I am aware that Azamara Quest is doing one or two this summer when then have two days in Sorrento, Ravenna and Venice, maybe this is what you are looking for. Lucy X