Pituitary adenoma is a slow-growing intracranial tumor with an incidence of about 1/100,000 people, accounting for 10% of intracranial tumors. In the last decade, clinical and basic research on pituitary tumors has developed rapidly. The application of radioimmunoassay and excitation/inhibition test of various hormones, as well as the progress of CT, MRI and other imaging examinations have advanced the diagnostic accuracy of pituitary adenoma by an era compared with the past diagnostic criteria of visual field, change of visual acuity and change of pterygoid saddle bone on X-ray. Together with the extensive development of modern microsurgery and radiation neurosurgery and the continuous improvement of various therapies, the total resection rate of pituitary adenoma has been greatly improved. According to domestic and foreign reports, the symptom improvement rate of small or miniature adenomas is 70% to 90% after resection, and the efficiency rate of large pituitary adenomas is 30% to 70% if they are completely resected. Due to the rapid development of molecular biology, the research of monoclonal occurrence of pituitary tumor and tumor-causing gene theory has deepened people’s understanding of pituitary tumor, thus opening up a broad prospect for the improvement of clinical therapy. In the past, scholars’ understanding of the mechanism of pituitary adenoma mainly includes two hypotheses: one is the theory of pituitary cells’ own defects; the other is the theory of hypothalamic dysregulation. At present, due to the development of molecular biology, the multi-step theory of pituitary adenoma has gradually unified the two theories; 2. Classification of pituitary adenomas In the past, pituitary adenomas were classified into four types: eosinophilic, basophilic, suspicious and mixed, according to the different pathological staining under light microscope. Mosa and Baroni first proposed the classification according to endocrine function in 1963, which was later improved by many scholars and is now classified as follows: (1) Adenomas with secretory function: including single hormone secreting adenomas and multi-hormone secreting adenomas; (2) Adenomas without secretory function: including undifferentiated adenomas and aneurysmal cell tumors. The treatment methods of pituitary adenoma include surgery, radiotherapy and drug therapy. Surgery is still the main treatment method for pituitary adenoma. The surgical route of pituitary adenoma has had many changes, and can be broadly divided into two kinds of craniotomy and transsphenoidal approach, which are described as follows; (1) transsphenoidal pituitary adenoma resection; ① The development of the operation transsphenoidal approach began with Schloffer, and in 1909 Cushing successfully applied transsphenoidal pituitary adenoma resection to treat a patient with acromegaly. In the absence of antibiotics at that time, the surgical mortality rate was lower than that of transcranial surgery, so it was considered the preferred approach for pituitary adenomas for a long time. However, it was gradually replaced by transcranial surgery because of its incomplete resection of the suprasellar septum, deep field and poor illumination. In the 1960s, Hardy et al. used the surgical microscope to improve the field exposure, so that the transsphenoidal approach could not only remove the adenoma, but also maintain the normal pituitary function. Pituitary surgery can also be performed to completely cure endocrine disorders in the body. Since then, the transsphenoidal approach to pituitary adenoma has been developed like never before. The application of endoscopy in pituitary adenoma resection Transendoscopic pituitary adenoma resection is a surgical procedure that has been developed and applied in recent years. Matulac et al. concluded that through neuroendoscopy, structures that cannot be observed by the general surgical microscope can be detected. More importantly, the use of endoscopy allows for an expanded scope of microsurgery to visualize posterior and peripheral structures, making it a safe and effective surgical approach in neurosurgery. In conclusion, the use of a nasal endoscope allows patients to heal more quickly by avoiding the traditional incisional approach and postoperative nasal tamponade. The endoscope allows the operator to see a panoramic view of the pterygoid sinus and avoid damage to the surrounding structures. And with improved illumination and magnification equipment, it provides an excellent view of the pterygoid saddle and supra-pterygoid area. This provides a good prospect for complete removal of the tumor and preservation of pituitary function to avoid neurovascular damage. In recent years, Dr. Ge has used the latest generation of high-definition neuroendoscope to perform endoscopic tumor resection for many patients with pituitary tumors, which has relieved the patients’ pain. (2) Transcranial pituitary adenoma resection In the past 20 years, the proportion of transcranial surgery has gradually decreased due to the popularity of transsphenoidal approach to pituitary tumor resection, and Massimo et al. counted 932 surgical patients, only 48 (5.1%) of whom underwent transcranial pituitary adenoma resection. However, due to the growth and expansion characteristics of pituitary tumors, each of these two approaches still has its own value; 4. Early screening for pituitary adenomas Early screening for pituitary adenomas in fertile women with menopause, lactation, infertility, healthy men with decreased sexual function, adults with significantly thicker limbs, thicker lips, larger nose, unexplained weight gain, and unexplained vision loss are all indicators of pituitary disorders and should be seen in a hospital. It is important to seek prompt medical attention.