Prolactin-secreting adenomas--surgical results

Reappraising the Role of Trans-Sphenoidal Surgery in Prolactin-Secreting Pituitary Tumors

Simple Summary

Prolactinomas constitute a subgroup of pituitary adenomas for which there are several treatment options. Dopamine agonists (DA), since their introduction, have shown a strong efficacy both in the control of hyperprolactinemia and of the significant volumetric reduction of prolactinomas, leading, in some cases, to a definitive cure. Trans-sphenoidal surgery (TSS) has been traditionally confined to a failure of medical therapy, pituitary apoplexy with neurological worsening, and prolactinomas with wide cystic components. Moreover, the recent technical innovations introduced in TSS and increasing experience of surgeons have allowed to achieve better results, such as complete tumor resection with lower complication rates. On these grounds, the authors reviewed the extensive institutional Prolactinomas case series over the last 25 years to analyze the role of TSS in the management of Prolactinomas, particularly in terms of the cure rate.

Abstract

Background: Prolactinomas represent a unique challenge for endocrinologists and neurosurgeons. Considering recent innovations in surgical practice, the authors aimed to investigate the best management for prolactinomas. Methods: A retrospective, cross-sectional and monocentric study was designed. Consecutive patients affected by prolactinomas were enrolled if treated with a first-line treatment with a dopamine agonist (DA) or trans-sphenoidal surgery (TSS). Patients carried giant prolactinomas, and those with a follow-up <12 months were excluded. Results: Two hundred and fifty-nine patients were enrolled. The first treatment was DA for 140 patients and TS for 119 cases. One hundred and forty-six of 249 patients (58.6%) needed a second therapy. The mean follow-up was 102.2 months (12–438 months). Surgery highly impacted on the cure rate—in particular, in females (p = 0.0021) and in microprolactinomas (p = 0.0020). Considering the multivariate analysis, the female gender and surgical treatment in the course of the clinical history were the only independent positive predictors of a cure at the end of 5 years follow-up (p = 0.0016, p = 0.0005). The evaluation of serum prolactin (24 hours after TSS) revealed that 86.4% of patients with postoperative prolactin (PRL) ≤10 ng/mL were cured at the end of the follow-up (p < 0.0001). Conclusions: According to our experience, surgery allows a high cure rate of prolactinomas, particularly in females with microadenoma, with a good safety profile. TSS for prolactinomas should be considered as a concrete option, during the multidisciplinary evaluation, in centers of reference for pituitary diseases.

Endoscopic endonasal approach for pituitary adenomas: a series of 555 patients

PURPOSE

To report the results of a consecutive series of patients who underwent an endoscopic endonasal approach (EEA) for resection of a pituitary adenoma and compare them to previous series of microscopic and endoscopic approaches.

METHODS

A retrospective review of clinical and radiographic outcomes of a consecutive series of patients operated at our center between 2002 and 2011 was performed.

RESULTS

555 patients underwent an EEA for removal of a pituitary adenoma. The mean follow up was 3.1 years (range 3 months to 9.5 years); 36 were lost to follow up. Ninety-one (17.5%) harbored recurrent adenomas. An expanded approach to reach the supra-, para- and infra-sellar spaces was employed in 290 patients (55.9%). Reconstruction with a nasal septal flap was used in 238 cases (65.6%). The rate of gross total resection was 65.3% in the 359 patients with non-functioning adenomas. The remission rates with EEA alone were 82.5% in the 57 ACTH-secreting adenomas, 65.3% in the 49 GH-secreting adenomas and 54.7% in the 53 prolactinomas. Of the 237 patients presenting with visual loss, 190 (80.2%) improved or normalized, 41 (17.3%) remained unchanged and 4 (1.7%) experienced transient visual deterioration due to postoperative apoplexy. In addition, no patient without preexisting visual loss suffered new visual decline. The overall post-operative CSF leak rate was 5% and this decreased to 2.9% after the introduction of reconstruction with the naso-septal flap. Two patients (0.3%) had an ICA injury.

CONCLUSIONS

The EEA is a safe and effective way to surgically approach pituitary adenomas, particularly in recurrent tumors, those with supra-sellar extension or cavernous sinus invasion. The remission and complication rates are comparable or favorable compared with those reported in previous series of microscopic and endoscopic approaches.

Endoscopic endonasal transsphenoidal surgery for functional pituitary adenomas

Object

The purpose of this study was to analyze preoperative predictors of endocrinological remission following endonasal endoscopic resection of therapy-resistant prolactin-, growth hormone (GH)–, and adrenocorticotropic hormone (ACTH)–secreting pituitary adenomas and to establish benchmarks for cure by using the most recent consensus criteria.

Methods

The authors reviewed a prospective database of 86 consecutive functional pituitary adenomas that were resected by a purely endoscopic endonasal transsphenoidal technique. Extent of resection was evaluated on postoperative contrast-enhanced MR imaging. Endocrinological remission was defined according to the most recent consensus criteria.

Results

The majority of functional adenomas (62.8%) were classified as macroadenomas (> 1 cm in maximum diameter), and 20.9% of lesions had invaded the cavernous sinus (CS) at the time of surgery. A gross-total resection was achieved in 75.6% of all patients. The rate of endocrinological remission differed between various types of functional adenomas. Cure rates were 92.3% (microadenomas) and 57.1% (macroadenomas) for prolactinomas, 75% (microadenomas) and 40% (macroadenomas) for GH-secreting tumors, and 54.5% (microadenomas) and 71.4% (macroadenomas) for ACTH-secreting tumors. Lower rates of cure occurred in GH-secreting macroadenomas due to a high rate of CS invasion, and in ACTH-secreting adenomas due to a high rate of lesions that were not visible on preoperative MR imaging. Whereas univariate analysis showed that macroadenoma, suprasellar, cavernous extension, or extent of resection correlated with cure, on multivariate analysis, only extent of resection and suprasellar extension predicted cure. One patient developed postoperative meningitis that was complicated by hydrocephalus requiring a ventriculoperitoneal shunt. Two patients developed postoperative panhypopituitarism, and 2 patients suffered from CSF leaks, which were treated with lumbar CSF diversion.

Conclusions

This paper reports benchmarks for endocrinological cure as well as complications in a large series of purely endoscopic pituitary surgeries by using the most recent consensus criteria. The advantages of extended endonasal approaches are most profound in tumors with suprasellar extension and CS invasion.

Pituitary tumors: surgical and medical management

The pituitary gland has been termed the 'master gland' because of the myriad of hormones that emanate from it that are vital for normal homeostasis as well as growth and development. Primary tumors of this region are frequent and account for up to 10% of intracranial tumors. Pituitary tumors are monoclonal in origin, and may arise from any of the different cell types of the pituitary gland. Hence, these tumors may be manifest by their hormonal secretions. This may lead to profound and striking physiological changes attributable, for example, to prolactin, growth hormone, or ACTH excess. The central location of the pituitary gland also leads to characteristic compressive symptoms. This review will explore the clinical presentations of growth hormone, ACTH, and prolactin secreting tumors as well as the non-secreting pituitary tumors. Advances in neuroimaging and neuropharmacology have resulted in changes in our treatment of these tumors. Treatment modalities including surgical, medical, and radiation therapy will be addressed. The treatment of choice is dictated by the type of tumor and the nature of the excessive hormonal expression. Outcomes and efficacy of treatment are discussed.

Role of radiation therapy in clinical hormonally-active pituitary adenomas

BACKGROUND AND PURPOSE

The outcome following radiation therapy (RT) of hormonally-active pituitary adenomas was assessed. The purpose of this analysis was to determine the control rate after radiation, identify any prognostic factors and evaluate the late toxicity.

MATERIALS AND METHODS

From 1972 to 1986, 145 patients received RT for hormonally-active pituitary adenomas. The median age was 39 years (range 15-76), with 81 males and 64 females. There were 52 patients with acromegaly, 64 with prolactinoma, and 29 with Cushing's disease. The median follow-up was 7.3 years. RT was given as primary treatment in 17 patients, after initial surgery in 65 patients, and as part of salvage therapy in 63 patients. The median total dose was 50 Gy (daily fraction: 2 Gy). Tumor control was defined as normalization of basal hormonal level and lack of progression of adenoma assessed by imaging studies. The following factors were analyzed for prognostic significance in tumor control: age, sex, tumor type, direction of tumor extension, radiation dose, and radiation field size.

RESULTS

The 10-year actuarial proportion of patients with persistent elevated hormone level were 61% following RT alone, and 44% with the addition of medical management. The progression-free rate was 96% at 10 years. Of the 20 deaths, three patients died with uncontrolled pituitary adenoma and three died of treatment complications. The actuarial 10-year overall and cause-specific survival rates were 86% and 97%. The actuarial rates of radiation-induced hypopituitarism were 35%, 22% and 22% at 10 years for thyroid, glucocorticoid and gonadal functions, respectively. None of the factors examined were found to be significant predictors of tumor control.

CONCLUSIONS

Post-operative external beam RT is highly effective in preventing recurrence of space-occupying effects of hormonally-active pituitary adenomas. However, long-term biochemical remission is observed only in approximately 40% of patients (at 10 years), with an additional 20% requiring medical therapy. Malignancies of the CNS can develop as an infrequent late event.