All pituitary tumor surgery is considered minimally invasive, and there are many modalities now doing pituitary tumor surgery, such as speculum and microsurgery. Craniotomy is also microsurgery, and after single nostril and combined oral and nasal, all pituitary tumor surgeries can now be performed under a microscope. Because of the different size and growth of the tumor, the surgeons do the surgery in different ways. Although different surgical approaches are taken, they are all less invasive and are all performed under microscope and speculum, and they are also minimally invasive surgeries. In particular, surgery under the scope is now often just a hole, invisible from the outside, while going in through a single nasal cavity to remove the tumor with less damage. Nowadays it is often a smaller bone flap, rarely open, and most of them are performed speculum or transnasal through a microscope, so they are all minimally invasive procedures. Both speculum and single nasal speculum or microscopic via single nasal cavity surgery are less invasive and less craniotomy invasive. The results of these surgical procedures are better, such as through single nasal cavity or microscope, although minimally invasive but the tumor will be cut cleanly, and sometimes the efficacy is better than open cranial.