Removal of pituitary tumors
What does pituitary gland surgery treat?
The removal of tumors coming from the hypophysis (or pituitary gland), an endocrine gland located at the base of the skull, is performed in the presence of tumors - benign in the large majority of cases - born from the gland itself. They are secretory pituitary adenomas, that is, hormone-producing or non-secreting adenomas. Other tumors affecting the sellar and/or suprasellar region, although not having their origin in the pituitary gland (craniopharyngiomas, meningiomas, metastases, Rathke's pouch cysts, chordomas) are of neurosurgical competence.
The purpose of the intervention is to radically remove the tumor, if the anatomical conditions allow it, without damaging the pituitary gland and its functionality. In some cases, where the functionality of the gland is already compromised by the presence of the tumor, the intervention can also allow an improvement in the hormonal situation. Similarly, when the presence of a large tumor leads to visual disturbances and/or a reduction in the visual field, the intervention allows, in the vast majority of cases, the normalization of the visual function or its marked improvement. In the cases of patients with secreting adenomas (GH, ACTH) the ablation of the tumor causes the scarring of the consequent endocrinopathy (respectively acromegaly, Cushing's disease) in more than 80% of the cases. Intervention is also indicated in TSH-secreting adenomas, while prolactin-producing (PRL) adenomas are treated with medical therapy and intervention is needed in a minority of subjects with tumors resistant to medical therapy or intolerant to the therapy itself.
How is the pituitary gland removed?
Removal of tumors from the pituitary region can be accomplished by means of transcranial access, or nasally and subsequent passage through the sphenoid bone (transphenoidal access). Transphenoidal access is the first choice in almost all cases as it provides better results with minimal side effects, since many of the previously mentioned tumors are predominantly located in the midline. The transcranial route is rather chosen in the case of tumors that laterally pass the plane formed by the optic nerves and the carotids.
If the transcranial approach is used, the patient is placed in the supine position on the operating bed under general anesthesia. Passing through the largest nostril, the ostium of the phenoid sinus is identified using the endoscope (in 3D) and a large opening in the anterior wall of the sphenoid is made. Once inside the sphenoid sinus, the sella turcica is identified, opened and the tumor removed trying to preserve the normal pituitary gland. At the end of the procedure, the saddle is closed with autologous bone or cartilage. In the event of a CSF leak, it may also be necessary to use a small piece of fat taken from the patient's abdomen.
Advantages and disadvantages of removal of pituitary adenomas?
Although modern surgical techniques allow pituitary adenomas to be removed while minimizing the risk of complications, the consequences the body faces can be endocrine-like. Hypopituitarism (insufficient secretion of pituitary hormones), to varying degrees, can occur in less than 10% of cases and in these patients it will be necessary to institute a replacement drug treatment (thyroid hormones, cortisol, estrogen, testosterone).
Is the removal of pituitary adenomas a painful and/or dangerous procedure?
The surgery is not particularly invasive and/or dangerous. Mortality is less than 1 case out of 1000 and overall endocrine or strictly surgical complications do not exceed 10% of cases overall. Post-operative headaches are generally mild and limited in time. In particular, the most modern endoscopic techniques guarantee fewer anatomo-functional alterations of the areas involved in the operation and faster postoperative follow-up than in the past.
Who can have surgery to remove a pituitary adenoma?
The patients for whom there may be particular contraindications to this type of surgical approach are the very elderly and/or frail and those with significant problems related to blood coagulation, as with any other surgical intervention.
Since the removal of a pituitary adenoma is a minimally invasive but extremely delicate procedure, it is advisable to rest a few days after the operation, also for recovery from anesthesia. After removal of the adenoma, the patient undergoes regular endocrinological and instrumental checks by means of magnetic resonance imaging.