Santiago isn't a cruise port, but is served by the ports of Valparaiso and Valparaiso. Together, the port of Valparaiso and Valparaiso acts as the embarkation for just one cruises every year from both MSC and Celebrity to South America.
Overall sailings from Santiago are fairly expensive compared to other ports. Check out the chart below for the monthly average cost per day (Cruises only depart from Santiago between January and March). Cruises leaving from Santiago during the the peak season of spring are somewhat more expensive than the the low season of winter.