An endoscopic instrument includes a forceps unit for being positioned within an anatomical cavity and a removable operating unit. The forceps unit includes a housing, an outer tubular member, an intermediate member, and a handle mechanism coupled with at least one of the intermediate and outer tubular members for creating relative movement between the intermediate and outer tubular members. The outer tubular member has a proximal end mounted by the housing and terminates distally at a distal end. The intermediate member has a tubular body disposed telescopically within the outer tubular member, a proximal end mounted by the housing and an integral one-piece distal end defining a pair of opposed jaws resiliently biased apart such that relative movement of the outer tubular member distal end over the jaws causes the jaws to close. The operating unit includes a hub mounting an inner tubular member removably disposed at least partly within the intermediate member and carrying operating members for performing at least one of the functions of cutting, grasping, manipulating, dissecting, collecting tissue for biopsy, penetrating tissue with a needle, injecting fluids, creating suction, aspirating, irrigating, suturing, ligating, visualizing, illuminating and cauterizing.