A modular handpiece having a proximal handle module with a handle unit (20) having at least one interior fluid cavity (128), having an exterior gripping surface, defining a fluid control port enabling fluid communication between the atmosphere and the interior fluid cavity (128), and capable of accommodating at least one waveguide for carrying optical radiation and capable of accommodating at least one RF electrode (24, 26). The handpiece further comprises a cannula module (14) having a distal portion (50) with a distal tip (60), a central portion (52), and a proximal portion (54) connectable with the handle module. All three cannula portions (50, 52, 54) are capable of at least one of (a) defining a waveguide conduit, (b) carrying at least one RF electrode, and (c) defining a fluid passageway between the distal tip and the interior fluid cavity (128) of the handle unit.
