Effects of preoperative octreotide treatment on different subtypes of 90 GH-secreting pituitary adenomas and outcome in one surgical centre

Abstract

Objective: To investigate the possible impact of pretreatment with octreotide on different subtypes of GH-secreting pituitary adenomas and on the outcome of transnasal surgery. Methods: We reviewed a consecutive series of 90 acromegalic patients treated with octreotide alone before transnasal surgery. On the basis of magnetic resonance imaging, the tumours were classi®ed into four groups: group A, microadenoma n 7; group B, transnasally resectable macroadenoma n 21; group C, invasive, potentially transnasally resectable macroadenoma n 43; group D, non-resectable grossly invasive macroadenoma n 19X All patients were treated for at least 3 months before surgery, with a mean daily dose of 221^31 mg octreotide. The mean follow-up was 51X7^1X4 months. The comparative group included 57 acromegalic patients who were not receiving octreotide treatment. Results: After pretreatment with octreotide, tumour shrinkage was clearly observed in 28 of the 90 patients (31%). At surgery, the tumours after octreotide treatment were more often white or grey in colour (91% compared with 75%) and were observed to be slightly more often¯uid or soft in texture (86% compared with 79%) than those in the comparative series. Endocrinological remission was achieved in all patients in group A, 95.2% in group B, and 81.4% in group C. In only 10 of the 14 patients with tumour shrinkage in group C, endocrinological remission was also achieved (71.4%). In the comparative series, endocrinological remission was achieved in 92.9% of group A, 87.5% of group B, and 73.9% of group C. Conclusions: Octreotide treatment slightly improved the already relatively high rate of endocrinological remission in invasive, potentially transnasally resectable macroadenomas. The rate of tumour shrinkage was found to decrease with extrasellar size. With the exception of tumour growth in approximately 7% of invasive adenomas and pituitary apoplexy in one patient, there was no disadvantage associated with the octreotide pretreatment. European Journal of Endocrinology 145 137±145

The outcome of surgery in 668 patients with acromegaly using current criteria of biochemical ‘cure’

“…All these problems must be carefully managed throughout the perioperative period in order to keep the complication rate as low as possible. In cases of markedly reduced general condition, short-term medical treatment with octreotide should be considered, which has proven very helpful in bringing the patient to a better condition before surgery (29,30).…”

Pathohistological classification of pituitary tumors: 10 years of experience with the German Pituitary Tumor Registry

“…Clearly, tumor size is a relevant prognostic marker for the success of any treatment. Surgical outcome was found to be better in patients with microadenomas of various types as compared with macroadenomas of these types (30)(31)(32). Primary medical treatment of GH-secreting pituitary adenomas with somatostatin analogs was more efficacious in microadenomas compared with macroadenomas (33).…”

“…In acromegaly, the most important prognostic factor was found to be the invasiveness of the adenoma which can be predicted by MRI and definitely proved by a thorough intraoperative inspection with adequate visualization methods. Therefore, the differentiation of resectable and incompletely resected or non-resectable adenomas is clinically relevant (31). This decision is made by the surgeon and not on the basis of tissue investigations.…”

Topoisomerase IIα as a prognostic factor in pituitary tumors

“…32,33 The use of somatostatin analogues, apart from achieving tumor shrinkage and better metabolic balance, also improves the efficiency of neurosurgery. [34][35][36] Low topo IIα index values in our patients treated with octreotide LAR provide evidence of their effectiveness, at the molecular level, in controlling GH-producing adenomas. Vidal et al 16 drew similar conclusions concerning topo IIα expression in patients who received preoperative treatment with somatostatin analogues.…”