During preoperative communication with patients in the clinic or ward, patients often ask if pituitary tumors will not recur after surgery. Doctors will often say that this is a case-by-case analysis, and that sometimes even if the surgery is cleaned up microscopically, there is still a possibility of recurrence. I believe that many patients will have a lot of lumps in their hearts when they hear this. Here I will give patients a more comprehensive analysis of the factors affecting pituitary tumor recurrence: 1. The degree of tumor excision and the residual amount of tumor are the main factors of recurrence. If the pituitary adenoma is completely removed during surgery, the possibility of recurrence is very small, while those who have only most of the tumor removed or partially removed have a higher possibility of recurrence. If the tumor is invisible on postoperative imaging and the blood endocrine hormones are normal, then there is almost no recurrence. If this tumor is invasive, without complete boundary, and the tumor wraps around the bilateral internal carotid arteries and multiple invasion in bilateral cavernous sinuses, no matter through craniotomy or transsphenoidal surgery, it is difficult to completely resect, and such tumors are often prone to recurrence.
2. Selection of surgical method. The surgical approach should be decided according to the volume of the tumor, the degree of invasion outside the saddle area and the operator’s proficiency in various accesses. Currently, the two main surgical approaches for pituitary adenoma are transcranial and transsphenoidal. It is reported that the recurrence rate of pituitary adenoma in transcranial surgery is 30%, and the recurrence rate of transsphenoidal approach is 7.75%-35%.
3. The characteristics of the tumor itself determine its recurrence. The size, texture and aggressiveness of pituitary adenoma all reflect that it has recurrence. Pituitary adenoma is usually located in the anterior lobe and the best time for total excision is when it grows in the shape of small nodules. There are also multiple pituitary adenomas and pituitary cell hyperplasia (nodular and diffuse hyperplasia), which are also difficult to be completely cut.
4. Endocrine factors. About 30% of people are prone to pituitary tumors after double adrenalectomy, and patients with long-term primary hypothyroidism or hypogonadism often have pituitary adenomas as a complication. Therefore, the probability of recurrence in these types of pituitary tumor patients will be further increased after surgery, which may be due to the long-term continuous loss of feedback regulation.
Ray reported that the recurrence rate was 8% in patients who had conventional radiotherapy after surgery and 22% in those who did not have radiotherapy. Therefore, the positive therapeutic effect of radiotherapy on pituitary adenoma has been recognized by most scholars. However, the latest view is that radiotherapy can prolong the recurrence period and reduce the recurrence rate, but cannot prevent recurrence. In view of the serious complications of postoperative radiotherapy, most scholars advocate emphasizing total tumor resection and close postoperative follow-up for small adenomas, but not routine postoperative radiotherapy, and early postoperative radiotherapy for large, infiltrative growth pituitary adenomas and those with residual tumor after surgery.
The recurrence of pituitary tumor after surgery is the result of a combination of factors. The nature of the tumor should be fully evaluated before surgery, as many tumors as possible should be removed during surgery, recurrence should be predicted by pathological results after surgery, regular blood hormone monitoring and imaging review, and combined radiotherapy if necessary to prevent or reduce postoperative pituitary tumor recurrence.