A cutting tool includes a cutting insert releasably retained therein. The cutting insert has top and bottom surfaces and a peripheral surface extending therebetween. The cutting insert does not include any clamping bore for receiving a clamping component therein. The cutting insert may having unitary, one-piece construction and be formed of a superabrasive material. The cutting insert may have a two-headed arrow shape, or similar shapes, such that the body of the cutting insert is small relative to the cutting regions thereof. The cutting tool includes a top clamp for clamping the cutting insert in an insert pocket. The top clamp has an asymmetrical shape and engages the cutting insert in one engagement region on the top surface, and in one engagement region on the peripheral surface. The cutting insert engages the insert pocket at the bottom surface, and in three spaced apart engagement regions on the peripheral surface.