Secretory or functional adenomas

• The secreting corticotroph adenoma is most often a microadenoma (<10mm) and secretes ACTH. It represents 6% of all adenomas. It is rare, affecting 1 to 6 people per million inhabitants per year. The average age at diagnosis is 40 years, with a clear female predominance. It is responsible for Cushing's Disease. Surgery by an expert neurosurgeon is the first-line treatment.
• The somatotroph adenoma secretes growth hormone (GH). It represents approximately 6% of all adenomas, affecting 1 to 6 people per million inhabitants per year. The age at the time of diagnosis is 47 years. It is responsible for Acromegaly. Diagnostic delay is common (4 to 10 years). Surgery by an expert neurosurgeon is often proposed as a first-line treatment. Complementary medical treatment may be indicated (somatostatin analogues).
• The prolactin adenoma (prolactinoma) is the most common pituitary adenoma, representing 60% of the total. Its prevalence is around 1/2,000. The average age at diagnosis is 32 years, with a clear female predominance (10:1 ratio). Medical treatment is often proposed as a first-line option (dopamine agonists).
• The thyrotroph adenoma secretes TSH. It is very rare (<1% of adenomas) and is most often accompanied by signs of hyperthyroidism. Treatment can be surgical or medical depending on the invasion of the cavernous sinus.

Non-secreting or non-functioning adenomas

They account for 30% of pituitary adenomas. Most of these tumors are gonadotropic adenomas. The term "non-functional" is more appropriate because, in about one-third of cases, there is hormonal expression during histological analysis, although there is no clinical impact.