Non-functioning pituitary adenoma underwent surgery: A multicenter retrospective study over the last four decades (1977-2015)

scRNA sequencing technology for PitNET studies

Pituitary neuroendocrine tumors (PitNETs) are common, most likely benign tumors with complex clinical characteristics related to hormone hypersecretion and/or growing sellar tumor mass. PitNET types are classified according to their expression of specific transcriptional factors (TFs) and hormone secretion levels. Some types show aggressive, invasive, and reoccurrence behavior. Current research is being conducted to understand the molecular mechanisms regulating these high-heterogeneous neoplasms originating from adenohypophysis, and single-cell RNA sequencing (scRNA-seq) technology is now playing an essential role in these studies due to its remarkable resolution at the single-cell level. This review describes recent studies on human PitNETs performed with scRNA-seq technology, highlighting the potential of this approach in revealing these tumor pathologies, behavior, and regulatory mechanisms.

Functioning Endocrine Outcome after Endoscopic Endonasal Transsellar Approach for Pituitary Neuroendocrine Tumors

BACKGROUND

The endoscopic endonasal approach (EEA) is a well-established technique for the treatment of pituitary neuroendocrine tumor Preservation of normal gland tissue is crucial to retain effective neuroendocrine pituitary function. The aim of this paper is to analyze pituitary endocrine secretion after EEA for pituitary neuroendocrine tumor to identify potential predictors of functioning gland recovery.

METHODS

Patients who underwent an exclusive EEA for pituitary neuroendocrine tumors between October 2014 and November 2019 were reviewed. Patients were divided into groups according to postoperative pituitary function (Group 1, unchanged; group 2, recovering; group 3, worsening).

RESULTS

Among the 45 patients enrolled, 15 presented a silent tumor and showed no hormonal impairment, and 30 patients presented pituitary dysfunction. A total of 19 patients (42.2%) were included in group 1, 12 (26.7%) patients showed pituitary function recovery after surgery (group 2), and 14 patients (31.1%) exhibited the onset of new pituitary deficiency postoperatively (group 3). Younger patients and those with functioning tumor were more likely to have complete pituitary hormonal recovery (p = 0.0297 and p = 0.007, respectively). No predictors of functional gland worsening were identified.

CONCLUSION

EEA for pituitary neuroendocrine tumor is a reliable and safe technique regarding postoperative hormonal function. Preserving pituitary function after tumor resection should be a primary goal in a minimally invasive approach.

Fatigue and Its Contributing Factors in Chinese Patients with Primary Pituitary Adenomas

Background. Pituitary adenomas (PAs) refers to a group of benign tumors that develop in the pituitary gland and are often characterized by fatigue. However, fatigue has not been documented in any Chinese research involving people with primary PA. The study sought to examine the prevalence, predictors, and correlation of fatigue with the quality of life (QoL) among PA patients in China. Methods. In total, 203 primary PA patients were included in this cross-sectional study. A series of questionnaires were administered, including the Multidimensional Fatigue Inventory (MFI), M. D. Anderson Symptom Inventory Brain Tumor (MDASI-BT), Short-Form 36 Health Survey (SF-36), Pittsburgh Sleep Quality Index (PSQI), and the Hospital Anxiety and Depression Scale (HADS). Data analysis was accomplished by Pearson or Spearman correlations, linear regression, and simple path analysis. Results. Severe fatigue prior to the initial diagnosis and preparation for surgery affected 50% of PA patients. Depression, sleep disturbance, and MDASI-BT symptom total scores were independently able to predict patient fatigue. Sleep disturbance mediates the influence of depression on fatigue (IE sleep = 0.296, 95% CI: LB = 0.148 to UB = 0.471). Conclusions. Chinese patients with primary PA often report experiencing fatigue. Depression and poor sleep quality were shown to be significant contributors to PA patients’ fatigue. Depression affects PA patients’ fatigue directly or indirectly. Medical professionals should take a proactive approach to PA patients suffering from fatigue before initial diagnosis and preoperative preparation to determine necessary interventions early, thus reducing fatigue and ultimately enhancing their QoL.

Single-cell sequencing identifies differentiation-related markers for molecular classification and recurrence prediction of PitNET

Pituitary neuroendocrine tumor (PitNET) is one of the most common intracranial tumors with variable recurrence rate. Currently, the recurrence prediction is unsatisfying and can be improved by understanding the cellular origins and differentiation status. Here, to comprehensively reveal the origin of PitNET, we perform comparative analysis of single-cell RNA sequencing data from 3 anterior pituitary glands and 21 PitNETs. We identify distinct genes representing major subtypes of well and poorly differentiated PitNETs in each lineage. To further verify the predictive value of differentiation biomarkers, we include an independent cohort of 800 patients with an average follow-up of 7.2 years. In both PIT1 and TPIT lineages, poorly differentiated groups show significantly higher recurrence rates while well-differentiated groups show higher recurrence rates in SF1 lineage. Our findings reveal the possible origin and differentiation status of PitNET based on which new differentiation classification is proposed and verified to predict tumor recurrence.

The outcomes of surgical treatment via transsphenoidal approach for patients with nonfunctioning pituitary adenoma: a single institution's experience

BACKGROUND

Nonfunctioning pituitary adenoma is a primary benign brain neoplasm and the transsphenoidal approach is known for a safe and effective first-line surgical treatment for pituitary tumours. The aim of this study was to retrospectively analyse the outcomes of the transsphenoidal approach for nonfunctioning pituitary adenomas treated at a single institute.

METHODS

A total of 181 patients who underwent transsphenoidal approach with nonfunctioning pituitary adenoma at a single institute from March 1998 to November 2018 were included in this study. Ninety-six (53.0%) men and 85 (47.0%) women aged 21-79 years were included. The median outpatient follow-up duration was 58 months, and the median magnetic resonance imaging follow-up duration was 54 months. We assessed the surgical and clinical outcomes, complications, hormonal outcomes and recurrence tendency.

RESULTS

The overall total resection rate of a transsphenoidal approach for nonfunctioning pituitary adenoma was 84.0%. Visual impairment was improved after surgery in 115 (93.5%) of 123 patients. Of the 80 patients who complained of preoperative endocrine dysfunction, 62 (77.5%) patients recovered normal postoperative endocrine function. Diabetes insipidus, which occurred in 22 (12.2%) patients, was the most common complication. A total of 21 (11.6%) patients showed recurrence on average 57.6 months after surgery. The average recurrence period after surgery was 96.3 months in the total resection group of 6 patients and 42.1 months in the subtotal resection group of 15 patients. In multivariate analysis, the extent of resection was identified as a significant predictor of tumour recurrence with a hazard ratio of 6.093 and a p-value of 0.002.

CONCLUSIONS

It is meaningful to report long-term surgical results within a single institution, and through this, it was reconfirmed that transsphenoidal approach is an effective and safe treatment for nonfunctioning pituitary adenoma. Long-term follow-up is required due to the possibility of recurrence. In addition, performing total resection during surgery helps to lower the risk of recurrence.KEY MESSAGESTranssphenoidal approach is an effective and safe treatment modality for pituitary adenoma.Complete resection is a significant predictor for the recurrence of pituitary adenomaLong-term follow-up is necessary for the treatment of nonfunctioning pituitary adenomas.

Pituitary Tumor Surgery: Comparison of Endoscopic and Microscopic Techniques at a Single Center

OBJECTIVE

To understand the transition from microscopic surgery (MS) to endoscopic surgery (ES) on the pituitary across the United States, we assessed a single institution practicing both procedures to discern advantages and disadvantages for each.

PATIENTS AND METHODS

Retrospective institutional chart review of 534 patients in a large practice over a 6-year period (January 1, 2014, to December 31, 2019) comparing a single MS neurosurgeon with a single ES neurosurgeon operating on the same days.

RESULTS

In this series, 14% (n=75) of patients had a prior operation, there were no carotid artery injuries, the overall risk for a postoperative infection was 0.4% (n=2), and risk for a postoperative cerebrospinal fluid leak requiring treatment was 2.0% (n=11). Mean ± SD hospital stay was 1.3±0.04 days; readmission for any reason within 30 days occurred in 3.4% (n=18) of patients. The mean volumetric resection for MS was 86.9%±1.7% and for ES was 91.7%±1.3% (P=.03). There was a higher rate of notable events (P=.015) with MS, but MS had 16% lower cost and operative times were 48 minutes shorter than for ES (83±7 vs 131±6 minutes). The ES required substantially fewer postoperative secondary treatments such as radiation therapy (P=.003).

CONCLUSION

Pituitary surgery is a very safe and effective procedure regardless of technique. The MS has shorter operative times and overall lower cost. The ES results in increased volumetric resection and fewer secondary treatments. Both techniques can be valuable to a large practice, and understanding these niches is important when selecting optimal approaches to pituitary surgery for a given patient.

Post-operative volumes following endoscopic surgery for non-functioning pituitary macroadenomas are predictive of further intervention, but not endocrine outcomes

BACKGROUND

Transsphenoidal surgery (TSS) remains the treatment of choice for non-functioning pituitary macroadenomas (NFPMA). The value of measuring tumour volumes before and after surgery, and its influence on endocrine outcomes and further treatment of the residual or recurrent tumour are unknown.

METHODS

Data from patients who underwent endoscopic TSS for a NFPMA (2009-2018) in a UK tertiary centre were analysed for pre- and post-operative endocrine and surgical outcomes.

RESULTS

Of 173 patients with NFPMA, 159 (61% male) were treatment naïve. At presentation, 76.2% (77/101) had ≥1 pituitary axis deficit. Older age (p = 0.002) was an independent predictor for multiple hormonal deficiencies. Preoperative tumour volume did not correlate with degree of hypopituitarism. Postoperative tumour volume and extent of tumour resection were not predictive of new onset hypopituitarism. Hormonal recovery was observed in 16 patients (20.8%) with impaired pituitary function, with the greatest recovery in the hypothalamic-pituitary-adrenal axis (21.2%, 7/33). A larger residual tumour volume was predictive of adjuvant radiotherapy (3.40 vs. 1.24 cm³, p = 0.005) and likelihood for repeat surgery (5.40 vs. 1.67cm³, p = 0.004).

CONCLUSION

Pre- and post-operative NFPMA volumes fail to predict the number of pituitary hormone deficits, however, greater post-operative residual volumes increase the likelihood of further intervention to control tumour growth.

Long-term outcomes after endoscopic endonasal surgery for nonfunctioning pituitary macroadenomas

OBJECTIVE

Nonfunctioning pituitary adenomas are benign, slow-growing tumors. After gross-total resection (GTR) or subtotal resection (STR), tumors can recur or progress and may ultimately require additional intervention. A greater understanding of long-term recurrence and progression rates following complete or partial resection and the need for further intervention will help clinicians provide meaningful counsel for their patients and assist data-driven decision-making.

METHODS

The authors retrospectively analyzed their institutional database for patients undergoing endoscopic endonasal surgery (EES) for nonfunctioning pituitary macroadenomas (2003-2014). Only patients with follow-up of at least 5 years after surgery were included. Tumor volumes were measured on pre- and postoperative MRI. Tumor recurrence was defined as the presence of a 0.1-cm3 tumor volume after GTR, and tumor progression was defined as a 25.0% increase in residual tumor after STR.

RESULTS

A total of 190 patients were included, with a mean age of 63.8 ± 13.2 years; 79 (41.6%) were female. The mean follow-up was 75.0 ± 18.0 months. GTR was achieved in 127 (66.8%) patients. In multivariate analysis, age (p = 0.04), preoperative tumor volume (p = 0.03), Knosp score (p < 0.001), and Ki-67 (p = 0.03) were significant predictors of STR. In patients with GTR, the probability of recurrence at 5 and 10 years was 3.9% and 4.7%, and the probability of requiring treatment for recurrence was 0.79% and 1.6%, respectively. In 63 patients who underwent STR, 6 (9.5%) received early postoperative radiation and did not experience progression, while the remaining 57 (90.5%) were observed. Of these, the probability of disease progression at 5 and 10 years was 21% and 24.5%, respectively, and the probability of requiring additional treatment for progression was 17.5% and 21%. Predictors of recurrence or progression in the entire group were Knosp score (p < 0.001) and elevated Ki-67 (p = 0.03). Significant predictors of progression after STR in those who did not receive early radiotherapy were cavernous sinus location (p < 0.05) and tumor size > 1.0 cm3 (p = 0.005).

CONCLUSIONS

Following GTR for nonfunctioning pituitary adenomas, the 10-year chance of recurrence is low and the need for treatment even lower. After STR, although upfront radiation therapy may prevent progression, even without radiotherapy, the need for intervention at 10 years is only approximately 20% and a period of observation may be warranted to prevent unnecessary prophylactic radiation therapy. Tumor volume > 1 cm3, Knosp score ≥ 3, and Ki-67 ≥ 3% may be useful metrics to prompt closer follow-up or justify early prophylactic radiation therapy.

Identification of driver genes and key pathways of non-functional pituitary adenomas predicts the therapeutic effect of STO-609

Objective

Our study is to identify DEGs (Differentially Expressed Genes), comprehensively investigate hub genes, annotate enrichment functions and key pathways of Non-functional pituitary adenomas (NFPAs), and also to verify STO-609 therapeutic effect.

Methods

The gene expression level of NFPA and normal tissues were compared to identify the DEGs (Differential expressed genes) based on gene expression profiles (GSE2175, GSE26966 and GSE51618). Enrichment functions, pathways and key genes were identified by carrying out GO (Gene Ontology), KEGG (Kyoto Encyclopedia of Genes and Genomes) analysis and PPI (Protein-Protein Interation) network analysis. Moreover, experiments in vitro were conducted to verify the anti-NFPAs effects of STO-609.

Results

169 over-expression genes and 182 low expression genes were identified among 3 datasets. Dopaminergic synapse and vibrio cholerae infection pathways have distinctly changed in NFPA tissues. The Ca²⁺/CaM pathway played important roles in NFPA. Four hub proteins encoded by genes CALM1, PRDM10, RIPK4 and MAD2L1 were recognized as hub proteins. In vitro, assays showed that STO-609 induced apoptosis of NFPA cells to inhibit the hypophysoma cellular viability, diffusion and migration.

Conclusion

Four hub proteins, encoded by gene CALM1, PRDM10, RIPK4 and MAD2L1, played important roles in NFPA development. The Ca²⁺/CaM signaling pathway had significant alternations during NFPA forming process, the STO-609, a selective CaM-KK inhibitor, inhibited NFPA cellular viability, proliferation and migration. Meanwhile, NFPA was closely related to parkinson’s disease (PD) in many aspects.

Ki67 in endocrine neoplasms: to count or not to count, this is the question! A systematic review from the English language literature

BACKGROUND

Endocrine neoplasms are generally slow-growing tumors that can show hormonal activity and give metastases. In most cases they are benign and clearly malignant forms are easy to diagnose. However, borderline forms may occur and be, for the pathologists, very difficult to classify. In these cases, there is a strong need to identify factors that may aid. Official classification systems for endocrine neoplasms are based on the evaluation of proliferation and, in most cases, they rely on mitotic count. In support, the study of Ki67 is carried out which, however, has not yet been included in any official classification system, except for neuroendocrine neoplasms of the gastro-entero-pancreatic tract.

PURPOSE

The aim of the present study was to investigate the proven or unproven role of Ki67 in endocrine neoplasms, in different districts, in order to bring to light the substantial differences, in terms of proliferation, existing between neoplasms so similar, but at the same time, so different.

METHODS

A thorough search of English language literature was performed, looking for articles concerning Ki67 in five endocrine neoplasms (pituitary adenomas, thyroid neoplasms, adrenocortical neoplasms, pheochromocytomas and paragangliomas).

RESULTS

From 2170, 236 articles were selected and it was seen that the endocrine neoplasm in which Ki67 was most studied was the pituitary, where it still shows a controversial role. In other neoplasms different roles were identified.

CONCLUSION

The pathologist should be aware of the contribution that this proliferative marker can give to the diagnosis and, sometimes, to the therapy selection, for the clinician.

Axis-specific analysis and predictors of endocrine recovery and deficits for non-functioning pituitary adenomas undergoing endoscopic transsphenoidal surgery

PURPOSE

Endoscopic transsphenoidal surgery (ETSS) is a well-established treatment for patients with nonfunctioning pituitary adenomas (NFPAs). Data on the rates of pituitary dysfunction and recovery in a large cohort of NFPA patients undergoing ETSS and the predictors of endocrine function before and after ETSS are scarce. This study is purposed to analyze the comprehensive changes in hormonal function and identify factors that predict recovery or worsening of hormonal axes following ETSS for NFPA.

METHODS

A retrospective review of 601 consecutive patients who underwent ETSS between 2010 and 2018 at one institution was performed. Recovery or development of new hypopituitarism was analyzed in 209 NFPA patients who underwent ETSS.

RESULTS

Patients with preoperative endocrine deficits (59.8%) in one or more pituitary axes had larger tumor volumes (P = 0.001) than those without preoperative deficits. Recovery of preoperative pituitary deficit occurred in all four axes, with overall mean recovery of 29.7%. The cortisol axis showed the highest recovery whereas the thyroid axis showed the lowest, with 1-year cumulative recovery rates of 44.3% and 6.1%, respectively. Postoperative hypopituitarism occurred overall in 17.2%, most frequently in the thyroid axis (24.3%, 27/111) and least frequently in the cortisol axis (9.7%, 16/165). Axis-specific predictors of post-operative recovery and deficiency were identified.

CONCLUSIONS

Dynamic alterations in pituitary hormones were observed in a proportion of patients following ETSS in NFPA patients. Postoperative endocrine vulnerability, recovery, and factors that predicted recovery or loss of endocrine function depended on the hormonal system, necessitating an axis-specific surveillance strategy postoperatively.

Pituitary Adenomas: What Are the Key Features? What Are the Current Treatments? Where Is the Future Taking Us?

Pituitary tumors are a heterogeneous group of lesions (usually benign) and proper understanding of the anatomy, physiology, and pathology of the hypothalamic/pituitary region is essential to make an accurate diagnosis and define the essential treatment options (i.e., surgery, medical therapies, and radiotherapy, alone or in combination). Surgery is the primary treatment for acromegaly, Cushing disease, thyroid-stimulating hormone-secreting adenomas, resistant prolactinomas, and nonfunctioning pituitary adenomas causing mass effect. Medical and radiation therapy are reserved in cases in which surgery is not possible or does not provide a complete cure. In the last decades, tremendous innovations (i.e., targeted drugs and refined surgical tools and techniques) have expanded the treatment strategies for pituitary adenomas. We herein report the current indications for and depiction of the surgical techniques in pituitary surgery, review current medical treatments, and provide a glimpse of future possibilities.

Giant Non-Functioning Pituitary Adenoma: Clinical Characteristics and Therapeutic Outcomes

Background Giant pituitary adenoma (≥4 cm) is a rare tumor whose clinical features and prognosis are not well known.

Aim To evaluate the clinical characteristics and therapeutic outcomes of giant non-functioning PA (gNFPA).

Patients and Methods A retrospective multicenter study of gNFPA patients diagnosed in a 12-year period was performed. In each patient, clinical data and therapeutic outcomes were registered.

Results Forty patients (24 men, age 54.2 ± 16.2 years) were studied. The maximum tumor diameter [median (interquartile range)] was 4.6 cm (4.1–5.1). Women had larger tumors [4.8 cm (4.2–5.4) vs. 4.5 cm (4.0–4.9); p=0.048]. Hypopituitarism [partial (n=22, 55%) or complete (n=9, 22.5%)] at diagnosis was present in 77.5% of the patients. Visual field defects were found in 90.9%. The most used surgical technique was endoscopic endonasal transsphenoidal (EET) surgery (n=31, 77.5%). Radiotherapy was used in 11 (27.5%) patients (median dose 50.4 Gy, range 50–54). Thirty-seven patients were followed for 36 months (10–67 months). Although more than half of these patients showed tumor persistence (n=25, 67.6%), tumor size was significantly reduced [0.8 cm (0–2.5); p<0.001]. At last visit, 12 patients (32.4%) showed absence of tumor on MRI. Hypopituitarism rate was similar (75.0%), although with significant changes (p<0.001) in the distribution of the type of hypopituitarism. The absence of tumor at the last visit was positively associated with positive immunohistochemical staining for FSH (p=0.01) and LH (p=0.006) and negatively with female sex (p=0.011), cavernous sinus invasion (p=0.005) and the presence of Knosp grade 4 (p=0.013).

Conclusion gNFPAs are more frequent in men but tumors are larger in women. Surgical treatment is followed by a complete tumor resection rate of approximately 30%. Positive immunostaining for gonadotropins is associated with tumor absence at last revision, while female sex and invasion of the cavernous sinuses with tumor persistence.

Non-functioning pituitary macroadenoma: surgical outcomes, tumor regrowth, and alterations in pituitary function-3-year experience from the Iranian Pituitary Tumor Registry

PURPOSE

The aim of this study was to assess clinical features and therapeutic outcomes in patients with clinically non-functioning pituitary macroadenomas (NFPMAs).

METHOD

This is a retrospective cohort study of NFPMA patients treated surgically and followed periodically between 2015 and 2017 in a tertiary care center in Iran. Descriptive analysis was performed applying appropriate tests. Binary logistic regression models were used to determine the predictive factors for subtotal tumor resection (STR) and hormonal recovery. Data were analyzed by Stata software.

RESULT

A total of 71 patients with a mean age of 50.6 ± 1.4 years were studied. The mean diameter of the adenoma was 26.8 ± 1.1 mm. The most frequent symptoms were headache (85.75%), visual field defect (VFD) (78.3%), and hypogonadal symptoms (40.3%). Gross total resection (GTR) was achieved in 45.1%. Preoperative hypopituitarism was observed in 50.7% of patients. Recovery of at least one axis occurred in 36.1% of the patients suffering from hypopituitarism preoperatively, while new-onset postoperative hormonal deficiency appeared in 14.3% of patients. Multivariate analyses showing preoperative tumor size (OR = 38.2; P = 0.008) and cavernous sinus extension (OR = 13.4; P = 0.020) were predictors of STR. Moreover, hormonal recovery was observed not to be related to age, gender, tumor size, or the extent of tumor resection.

CONCLUSIONS

Tumor size and cavernous sinus extension are the main predictors for STR. Notably, recovery of the gonadal axis in a large proportion of patients supports the surgical resection of NFPAM in patients suffering from gonadal deficiency, even in the absence of VFD.

Transsphenoidal surgery: accuracy of an image-guided neuronavigation system to approach the pituitary fossa (sella turcica)

OBJECTIVE

To determine the accuracy of locating the pituitary fossa with the Brainsight neuronavigation system by determining the mean target error of the rostral (tuberculum sellae) and caudal (dorsum sellae) margins of the pituitary fossa.

STUDY DESIGN

Experimental cadaveric study.

ANIMALS

Ten canine cadavers.

METHODS

Computed tomography (CT) and MRI were performed on each cadaver with fiducials in place. Images were saved to the neuronavigation computer and used to plan the drilling approach. The cadavers were placed in the surgical head clamp of the Brainsight system and positioned for a transsphenoidal approach. On the basis of the planning, 2 localization points were drilled, 1 each at the rostral and caudal margins of the pituitary fossa, and CT was repeated. Error was assessed from the difference in millimeters between the targets identified during Brainsight planning and the actual location of the 2 points drilled on each cadaver skull as identified by postdrilling CT.

RESULTS

The rostral and caudal margins of the pituitary fossa provided 2 target points per cadaver. The median target error (interquartile range) for all target sites (n = 20) was 3.533 mm (range, 2.013-4.745).

CONCLUSION

This stereotactic system allowed the surgeon to locate the rostral and caudal margins of the pituitary fossa with clinically acceptable accuracy and confidence.

CLINICAL SIGNIFICANCE

Using the Brainsight neuronavigation system for localization during transsphenoidal hypophysectomy may decrease morbidity and surgical time.

Management of non-functioning pituitary adenomas: surgery

Non-functional pituitary adenomas (NFPAs) are benign tumors of the pituitary gland that do not over-secrete hormonal products, therefore, they are generally detected through symptoms of mass effect, including headache, vision loss, or hypopituitarism. There are multiple pathological subtypes of NFPAs, such as null cell adenomas, silent gonadotrophs, silent somatotrophs, silent corticotrophs, and silent subtype 3, all of which can be classified based on immunohistochemical studies and electron microscopy. Despite these numerous pathological subtypes, surgical resection remains the first-line treatment for NFPAs. Diagnosis is best made using high resolution MRI brain with and without gadolinium contrast, which is also helpful in determining the extent of invasion of the tumor and recognizing necessary sinonasal anatomy prior to surgery. Additional pre-operative work-up should include full laboratory endocrine evaluation with replacement of hormone deficiencies, and ideally, full neuro-ophthalmologic exam. Although transcranial surgical approaches to the pituitary gland can be performed, the most common approach used is the transnasal transsphenoidal approach with endoscopic or microscopic visualization. This approach avoids retraction of the brain and cranial nerves during tumor removal. Surgery for symptoms caused by mass effect, including headaches and visual loss, are successfully treated with surgical resection, resulting in improvement in pre-operative symptoms as high as 90% in some reports. Although the risk of complications is low, major and minor events, such as permanent hypopituitarism, persistent CSF leak, and carotid artery injury can occur at rates ranging from zero to about 9%.

Management of NFAs: medical treatment

INTRODUCTION

Non-functioning pituitary adenomas (NFPAs) are in general large tumors that present with symptoms secondary to local pressure on adjacent structures. Transsphenoidal surgery is the first line of treatment but residual tumor mass is often detected post-operatively. Medical therapy, in any stage of tumor management, is not well established.

METHODS

A literature search was performed to review the available data on medical treatment of NFPAs.

RESULTS

Medications investigated for the treatment of NFPAs include dopamine receptor agonists (DA) and somatostatin receptor ligands. Randomized controlled trials are lacking, but available data suggest that DA have a positive effect on tumor remnant stabilization after surgery and could be considered in this setting. Temozolomide is reserved for aggressive tumors, although future studies are required.

CONCLUSIONS

NFPA are often not amenable to complete surgical resection. Conservative follow-up after surgery is associated with a high prevalence of tumor remnant progression. DA therapy may prevent residual tumor enlargement in over 85% of these patients, with a substantial consequent reduction in the need for repeat surgery or radiation therapy. It is our view that DA treatment should be routinely considered for the management of NFPA patients with incompletely resected tumors.