A microwave antenna assembly comprising: a feedline including an inner conductor, an outer conductor and an inner insulator disposed therebetween; a radiating portion including a dipole antenna coupled to the feedline and a trocar coupled to the dipole antenna at a distal end thereof; an inner fluid feed member disposed around the outer conductor in electro-mechanical contact therewith, the inner fluid feed member having a plurality of fluid lumens defined therein configured to supply a fluid to the radiating portion; and an outer fluid feed member disposed around the inner fluid feed member in electro-mechanical contact therewith, the outer fluid feed member having a plurality of fluid lumens defined therein configured to withdraw the fluid from the radiating portion.