Mean tumour size by clinical palpation at T = 0 was 39.1 mm ( 95 % CI 34.8-43 .4 mm ) , and decreased to 23.0 mm ( 95 % CI 18.7-27 .2 mm ) and 16.7 mm ( 95 % CI 12.6-20 .8 ) at T = 3 and T > 3 months , respectively ( p = 0.001 ) .