An expandable adapter collar assembly is provided for use with a surgical access port having an outer diameter in order to increase the apparent outer diameter of the combination of the surgical access port and expandable collar in order to conform to the size of a surgical incision. The expandable adapter collar is an inflatable collar which is selectively detachably positionable so as to surround the surgical access port and expandable from a deflated or contracted smaller diameter to an inflated or expanded larger diameter to fill the surgical incision. The expandable adapter collar may be provided as part of an expandable collar assembly including a source of inflation fluids. There is also provided a method of adapting a surgical access port for use in a surgical incision having a size larger than the original design parameters for the surgical access port.