Relationship between postoperative volume of macroadenomas and clinical outcome after endoscopic trans-sphenoidal...

Although symptoms are expected to improve after the resection of pituitary macroadenomas, tumor resection volume does not always correlate with the patient's symptoms. Our objectives were to assess the pre and postoperative volumes of pituitary macroadenomas before, immediately after surgery and at follow-up, and to explore possible associations and correlations among these changes and symptoms.

We retrospectively reviewed the clinical records and the preoperative and postoperative magnetic resonance imaging studies at 24 hours and at 3, 6 and 9 months follow-up of 146 patients who underwent surgery for pituitary macroadenomas. We measured tumor volumes before and after surgery and compared changes with symptom improvement.

The mean preoperative tumor volume was 24.66 cm³ (standard deviation 65.18 cm³, 95% confidence interval (CI) 14-35.32). The most common symptoms were visual/cranial nerve abnormalities (65%) and headaches (56%). Immediately after surgery, symptoms persisted without significant changes in all patients. A progressive tumor volume decrease was noted during follow-up, and symptoms improved in 78% of patients. Despite no imaging evidence of chiasm or cavernous sinus compression, 32 patients showed no symptom improvement. Patients with symptoms for more than 1 year (mean duration of symptoms 26 months, SD 24.3, 95% CI 22.03-29.97 months) had a higher risk of the persistence of symptoms compared to patients with a mean duration of symptoms of less than 1 year (odds ratio 2.5, 95% CI 2.4-3, P < 0.005).

The duration of symptoms prior of surgery is a more important factor than tumor resection volume alone when considering the long-term outcome of symptoms. Furthermore, lack of symptom improvement in the immediate postoperative period does not necessarily represent an inadequate resection.