A method and system for removing an organ or piece of tissue severed from its supporting tissue within a patient's body cavity, such as the abdominal cavity, which includes an elongated expandable tubular member with a sealed interior. In one preferred embodiment for morcellation, means are provided within the sealed interior to tear or cut off tissue fragments from the organ or tissue which are small enough to pass out of the patient's body cavity through an inner lumen of an exit trocar sheath disposed within the patient and in communication with the body cavity. The organ or piece of tissue is placed within an inner lumen defined by the sealed interior through an opening provided in a leading portion of the elongated expandable tubular member. The organ or piece of tissue is fragmented into smaller pieces which are withdrawn from the patient's body cavity by the passage of the morcellation system through the inner lumen of the exit trocar sheath. In one embodiment of the morcellation system, one or more elongated cutting strips are disposed within the inner lumen defined by the sealed interior and secured to the lining to cut or tear the tissue into small fragments. In another embodiment of the invention one or more elongated helical ribbons are provided to cut or tear the tissue into small fragments.