Assessment of long-term remission of acromegaly following surgery

Early postoperative growth hormone measurement as a predictive marker for acromegaly remission

Growth hormone (GH) has a short half-life and declines abruptly following somatotropinoma surgery, enabling its prompt measurement as an indicator of surgical success. This study assesses the predictive value of early postoperative GH levels for 3-month and >1-year remission of acromegaly. We conducted a retrospective search in our database of patients who had undergone transsphenoidal surgery of GH-secreting pituitary adenoma from January 2011 to June 2022. Only the patients who underwent the first pituitary surgery and had GH measurements on the fifth postoperative day were included. The 3-month and >1-year remission of acromegaly was defined as achieving the GH nadir of <0.4 μg/L during an oral glucose tolerance test and maintaining normal insulin-like growth factor 1 levels at the initial follow-up visit 3 months after surgery and throughout at least the first year postoperation. We included 63 patients in the analysis, with a median follow-up of 51.8 (13-155) months. The 3-month remission was achieved in 42 (66.7%) patients, and >1-year remission without additional therapy in 38 (60.3%) patients. Those who achieved >1-year remission had significantly lower fifth-day postoperative GH levels (0.59 [0.09-8.92] vs. 2.63 [0.25-24.64] μg/L, p < .001). Receiver-operating characteristic analysis revealed a significant value of fifth-day postoperative GH levels regarding the prediction of 3-month (area under the curve [AUC], 0.834; p < .0001) and >1-year (AUC, 0.783; p < .0001) acromegaly remission. The GH threshold of ≤1.57 μg/L yielded a sensitivity of 90.5% and a specificity of 71.4% at 3 months and 89.5% sensitivity and 60% specificity at the >1-year remission, respectively. Notably, all patients with fifth-day postoperative GH levels ≤0.23 μg/L exhibited remission of acromegaly throughout the follow-up period. Early postoperative GH measurement could be a reliable predictor of both 3-month and >1-year remission of acromegaly.

Recurrence in acromegaly: two tertiary centers experience and review of the literature

BACKGROUND

Recurrence of acromegaly after successful surgery is a rare event, but no clear data are reported in the literature about its recurrence rates. This study aimed to evaluate the recurrence rate in a series of acromegalic patients treated by transsphenoidal surgery (TSS) with a long follow-up.

METHODS

We retrospectively analyzed data from 283 acromegalic patients who underwent TSS at two pituitary units in Milan (Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico and IRCCS Humanitas Research Hospital). The diagnosis and recurrence of acromegaly were defined by both elevated IGF-1 levels and a lack of GH suppression based on appropriate criteria for the assay used at the time of diagnosis.

RESULTS

After surgery, 143 patients (50%) were defined as not cured, 132 (47%) as cured and 8 (3%) as partially cured because of normalization of only one parameter, either IGF1 or GH. In the cured group, at the last follow-up (median time 86.8 months after surgery), only 1 patient (0.7%) showed full recurrence (IGF-1 + 5.61 SDS, GH nadir 1.27 µg/l), while 4 patients (3%) showed only increased IGF1. In the partially cured group at the last follow-up, 2/8 (25%) patients showed active acromegaly (IGF-1 SDS + 2.75 and + 3.62; GH nadir 0.6 and 0.5 µg/l, respectively).

CONCLUSIONS

In the literature, recurrence rates range widely, from 0 to 18%. In our series, recurrence occurred in 3.7% of patients, and in fewer than 1%, recurrence occurred with elevation of both IGF-1 and the GH nadir. More frequently (25%), recurrence came in the form of incomplete normalization of either IGF-1 or GH after surgery.

Consensus on criteria for acromegaly diagnosis and remission

PURPOSE

The 14th Acromegaly Consensus Conference was convened to consider biochemical criteria for acromegaly diagnosis and evaluation of therapeutic efficacy.

METHODS

Fifty-six acromegaly experts from 16 countries reviewed and discussed current evidence focused on biochemical assays; criteria for diagnosis and the role of imaging, pathology, and clinical assessments; consequences of diagnostic delay; criteria for remission and recommendations for follow up; and the value of assessment and monitoring in defining disease progression, selecting appropriate treatments, and maximizing patient outcomes.

RESULTS

In a patient with typical acromegaly features, insulin-like growth factor (IGF)-I > 1.3 times the upper limit of normal for age confirms the diagnosis. Random growth hormone (GH) measured after overnight fasting may be useful for informing prognosis, but is not required for diagnosis. For patients with equivocal results, IGF-I measurements using the same validated assay can be repeated, and oral glucose tolerance testing might also be useful. Although biochemical remission is the primary assessment of treatment outcome, biochemical findings should be interpreted within the clinical context of acromegaly. Follow up assessments should consider biochemical evaluation of treatment effectiveness, imaging studies evaluating residual/recurrent adenoma mass, and clinical signs and symptoms of acromegaly, its complications, and comorbidities. Referral to a multidisciplinary pituitary center should be considered for patients with equivocal biochemical, pathology, or imaging findings at diagnosis, and for patients insufficiently responsive to standard treatment approaches.

CONCLUSION

Consensus recommendations highlight new understandings of disordered GH and IGF-I in patients with acromegaly and the importance of expert management for this rare disease.

Recurrent acromegaly: a systematic review on therapeutic approaches

BACKGROUND AND OBJECTIVE

Management of recurrent acromegaly is challenging for both neurosurgeons and endocrinologists. Several treatment options including repeat surgery, medical therapy, and radiation are offered for such patients. The efficacy of these modalities for the treatment of recurrence has not been studied previously in the literature. In this study, we aim to systematically review the existing cases of recurrence and come to a conclusion regarding the appropriate treatment in such cases.

METHOD

A systematic review was performed through PubMed, Scopus, Web of Science, and Cochrane database to identify studies reporting the treatment outcome of recurrent acromegaly patients. Using PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, the included studies were reviewed for primary and secondary treatment, complications, and outcomes of the secondary treatment.

RESULTS

The systematic review retrieved 23 records with 95 cases of recurrent acromegaly. The mean time of recurrence was 4.16 years after the initial treatment. The most common primary treatment was surgery followed by radiotherapy. The remission rate was significantly higher in medical and radiotherapy compared to surgical treatment.

CONCLUSION

In cases of recurrent acromegaly, the patient may benefit more from radiotherapy and medical therapy compared to surgery. As the quality of evidence is low on this matter feature studies specifically designed for recurrent patients are needed.

Serum Phosphorus and Calcium as Biomarkers of Disease Status in Acromegaly

Acromegaly is a chronic disease caused by the hypersecretion of growth hormone (GH), leading to changes in the growth of visceral tissues and glucose impairment. Serum biomarkers that correlate with disease status are still unclear. This study aims to assess the potential of phosphorus and calcium as biomarkers in the clinical evaluation of patients with acromegaly and clarify their relationship with SAGIT and other common biomarkers. We retrospectively analyzed data from 306 medical records of patients with acromegaly hospitalized between 2015 and 2020. Factors such as patient biometrics, duration of disease, SAGIT score, tumor size, GH, insulin-like growth factor 1 (IGF-1), calcium, phosphorus, parathormone, and vitamin D were analyzed concerning current disease status (naïve, non-remission, remission). The results showed that serum phosphorus significantly correlated with IGF-1 and SAGIT scores for patients with active acromegaly. Specifically, the best predictor for the remission of acromegaly was a phosphorus level < 3.98 mg/dL and serum calcium levels < 9.88 mg/dL. Based on logistic regression, the higher the serum phosphorus level, the lower the odds of achieving remission (an increase in one unit leads to a decrease in the chance of about 80%). In conclusion, phosphorus and calcium can be effective biochemical markers for predicting disease status in acromegaly.

Executive summary of the expert consensus document from the Spanish Society of Neurosurgery and the Spanish Society of Endocrinology and Nutrition: Clinical recommendations on the perioperative management of pituitary tumors

Pituitary tumors (PT) account for 15% of intracranial tumors affect 10.7%-14.4% of the population although the incidence of clinically relevant PT is 5.1 cases/100,000 inhabitants. Surgical treatment is indicated in PTs with hormone hypersecretion (except for prolactin-producing PTs) and those with local compressive or global neurological symptoms. Multidisciplinary care, is essential for patients with PTs, preferably delivered in a center of excellence and based on a well-defined care protocol. In order to facilitate and standardize the clinical procedures for this type of tumor, this document gathers the positioning of the Neuroendocrinology Knowledge Area of the Spanish Society of Endocrinology and Nutrition (SEEN) and the Spanish Society of Neurosurgery (SENEC) on the management of patients with PTs and their preoperative, surgical and postoperative follow-up.

Executive summary of the expert consensus document from the Spanish Society of Neurosurgery and the Spanish Society of Endocrinology and Nutrition: clinical recommendations on the perioperative management of pituitary tumors

Pituitary tumors (PT) account for 15% of intracranial tumors affect 10.7-14.4% of the population although the incidence of clinically relevant PT is 5.1 cases/100,000 inhabitants. Surgical treatment is indicated in PTs with hormone hypersecretion (except for prolactin-producing PTs) and those with local compressive or global neurological symptoms. Multidisciplinary care, is essential for patients with PTs, preferably delivered in a center of excellence and based on a well-defined care protocol. In order to facilitate and standardize the clinical procedures for this type of tumor, this document gathers the positioning of the Neuroendocrinology Knowledge Area of the Spanish Society of Endocrinology and Nutrition (SEEN) and the Spanish Society of Neurosurgery (SENEC) on the management of patients with PTs and their preoperative, surgical and postoperative follow-up.

Intraoperative Prediction of Long-Term Remission in Acromegaly

BACKGROUND

The features of long-term remission in acromegaly adenomectomy are incompletely understood. An intraoperative predictor for long-term outcome would be valuable for assessing resection of growth hormone (GH)-secreting tumors in real-time.

OBJECTIVE

To evaluate whether intraoperative GH measurement could predict long-term outcomes for acromegaly.

METHODS

In 47 patients, peripheral blood GH levels were measured thrice intraoperatively: once before tumor dissection, once during tumor dissection, and once after tumor dissection. Long-term remission was defined by age-appropriate, normalized insulin-like growth factor-1 at most recent follow-up and a random GH less than 1.0 ng/mL. Patients were only considered to be in long-term remission without the use of postoperative medical therapy for acromegaly or radiation therapy.

RESULTS

The median length of follow-up was 4.51 (range: 0.78-9.80) years. Long-term remission was achieved in 61.7% (29/47) of operations. Like previous studies, cavernous sinus invasion (odds ratio [OR]: 0.060; 95% CI: 0.014-0.260; P value < .01), suprasellar extension (OR: 0.191; 95% CI: 0.053-0.681; P value<.01), and tumor size greater than 1 cm (OR: 0.177; 95% CI: 0.003-0.917; P value = .03) were associated with not being in long-term remission. The minimum GH measured intraoperatively predicted long-term outcome (area under the curve: 0.7107; 95% CI: 0.537-0.884; P value < .01). The odds ratio of remission in patients with the lowest quartile minimum intraoperative GH compared with patients with the highest quartile minimum intraoperative GH was 27.0 (95% CI: 2.343-311.171; P value < .01).

CONCLUSION

Minimum intraoperative GH may predict long-term outcome for acromegaly, which in principle could provide the pituitary neurosurgeon with real-time feedback and inform intraoperative decision making.

Pituitary Adenomas: Classification, Clinical Evaluation and Management

Pituitary adenomas are one of the most common brain tumors. They represent approximately 18% of all intracranial, and around 95% of sellar neoplasms. In recent years, our understanding of the pathophysiology and the behavior of these lesions has led to better control and higher curative rates. The treatment decision is largely dependent on type of the adenoma, clinical presentation, and the size of the lesion. In addition, incidental pituitary lesions add uncertainty in the decision-making process, especially for pituitary adenomas that can be medically managed. When surgery is indicated, the endoscopic endonasal transsphenoidal approach is the technique of choice, but open standard craniotomy approaches can also be the option in selected cases. The following chapter will review the classification, clinical presentation, pathophysiology, diagnostic work-up, selection of surgical approach, and treatment complications in pituitary adenomas.

Outcomes in pituitary adenoma causing acromegaly following endoscopic endonasal transsphenoidal surgery

Objectives

The objectives of the study were to study the analysis of outcomes after endoscopic endonasal transsphenoidal surgery (EETSS) in acromegaly in terms of surgical complications, clinical improvement, endocrinological remission, achievement of prognostically critical growth hormone (GH) level, and requirement of additional treatment.

Materials and Methods

The study included 28 acromegaly patients, who underwent EETSS. A 2010 consensus criterion was used for defining remission. Assessment of prognostically critical GH level (random value <2.5 ng/ml), the extent of resection and additional treatment, was done at post-operative week (POW) 12.

Results

All adenomas were macroadenomas; with a mean volume of 16.34 cm3 (range, 0.4-99 cm3). Most adenomas had high-grade extensions. Most common suprasellar, infrasellar, anterior, and posterior extension grades were 3 (n = 13), 1 (n = 16), 1 (n = 14), and 0 (n = 20), respectively. Knosp Grade 3 was common on both sides (right, n = 9 and left, n = 8). One patient had already been operated on with EETSS, 1.5 years back from current surgery. Sixteen patients were on hormonal support, preoperatively. Four patients died during follow-up. Post-operative common complications were diabetes insipidus (DI, n = 18), cerebrospinal fluid rhinorrhea (n = 10), surgical site hematoma (n = 3), meningitis (n = 3), hydrocephalus (n = 2), and syndrome of inappropriate antidiuretic hormone (n = 1). The mean hospital stay was 11.62 days and 12.17 months were the mean follow-up period. At 12 POW, no improvement was seen in body enlargement and visual complaints, but all other complaints improved significantly except perspiration. Adenomas were decreased in all extensions except posterior and mean adenoma volume was reduced from 16.34 cm3 to 2.92 cm3 after surgery. Sub-total resection (STR, n = 10), near-total resection (NTR, n = 7), gross-total resection (GTR, n = 5), and partial resection (PR, n = 2) were achieved. Endocrinological remission and prognostically critical GH levels were attained in 29.17% (n = 7) and 66.67% (n = 16), respectively. NTR, GTR, STR, and PR were associated with 57.14%, 40%, 10%, and 0% endocrinological remission, respectively. Additional treatment was required in a total of 17 patients, three in GTR, nine in STR, three in NTR, and two in PR. Ten were treated with Gamma Knife radiosurgery along with medical treatment and seven with medical treatment alone.

Conclusion

A successful EETSS can reduce adenoma volume to achieve clinical improvement, endocrinologic remission, and prognostically critical GH level with some complications related to surgery. Pre-operative larger volume and higher extension grades affect these outcomes adversely.

Outcomes in Pituitary Adenoma Causing Acromegaly Following Endoscopic Endonasal Transsphenoidal Surgery

Objectives The objective of this study was the analysis of outcomes after endoscopic endonasal transsphenoidal surgery (EETSS) in acromegaly in terms of surgical complications, clinical improvement, endocrinological remission, achievement of prognostically critical growth hormone (GH) level, and requirement of additional treatment.

Materials and Methods The study included 28 acromegaly patients, who underwent EETSS. 2010 consensus criterion was used for defining remission. Assessment of prognostically critical GH level (random value less than 2.5 ng/mL), the extent of resection, and additional treatment was done at postoperative week (POW) 12.

Results All adenomas were macroadenomas, with the mean volume of 16.34 cm3 (range, 0.4–99 cm3). Most adenomas had high-grade extensions. Most common suprasellar, infrasellar, anterior, and posterior extension grades were 3 (n = 13), 1(n = 16), 1(n = 14), and 0 (n = 20), respectively. Knosp grade 3 was common on both sides (right, n = 9 and left, n = 8). One patient had already been operated on with EETSS, 1.5 years back from current surgery. Sixteen patients were on hormonal support, preoperatively. Four patients died during follow-up. Postoperative common complications were diabetes insipidus (n = 18), cerebrospinal fluid rhinorrhea (n = 10), surgical site hematoma (n = 3), meningitis (n = 3), hydrocephalus (n = 2), and syndrome of inappropriate antidiuretic hormone (n = 1). The mean hospital stay was 11.62 days, and 12.17 months was the mean follow-up period. At 12 POW, no improvement was seen in body enlargement and visual complaints, but all other complaints improved significantly except perspiration. Adenomas were decreased in all extensions except posterior, and mean adenoma volume was reduced from 16.34 to 2.92 cm3 after surgery. Subtotal resection (STR, n = 10), near-total resection (NTR, n = 7), gross-total resection (GTR, n = 5), and partial resection (PR, n = 2) were achieved. Endocrinological remission and prognostically critical GH levels were attained in 29.17% (n = 7) and 66.67% (n = 16), respectively. NTR, GTR, STR, and PR were associated with 57.14, 40, 10, and 0% endocrinological remission, respectively. Additional treatment was required in a total of 17 patients: 3 GTR, 9 STR, 3 NTR, and 2 PR patients. Ten patients were treated with gamma knife radiosurgery along with medical treatment and seven with medical treatment alone.

Conclusion A successful EETSS can reduce adenoma volume to achieve clinical improvement, endocrinological remission, and prognostically critical GH level with some complications related to surgery. Preoperative larger volume and higher extension grades affect these outcomes adversely.

Machine learning as a clinical decision support tool for patients with acromegaly

OBJECTIVE

To develop machine learning (ML) models that predict postoperative remission, remission at last visit, and resistance to somatostatin receptor ligands (SRL) in patients with acromegaly and to determine the clinical features associated with the prognosis.

METHODS

We studied outcomes using the area under the receiver operating characteristics (AUROC) values, which were reported as the performance metric. To determine the importance of each feature and easy interpretation, Shapley Additive explanations (SHAP) values, which help explain the outputs of ML models, are used.

RESULTS

One-hundred fifty-two patients with acromegaly were included in the final analysis. The mean AUROC values resulting from 100 independent replications were 0.728 for postoperative 3 months remission status classification, 0.879 for remission at last visit classification, and 0.753 for SRL resistance status classification. Extreme gradient boosting model demonstrated that preoperative growth hormone (GH) level, age at operation, and preoperative tumor size were the most important predictors for early remission; resistance to SRL and preoperative tumor size represented the most important predictors of remission at last visit, and postoperative 3-month insulin-like growth factor 1 (IGF1) and GH levels (random and nadir) together with the sparsely granulated somatotroph adenoma subtype served as the most important predictors of SRL resistance.

CONCLUSIONS

ML models may serve as valuable tools in the prediction of remission and SRL resistance.

Machine learning-based clinical outcome prediction in surgery for acromegaly

PURPOSE

Biochemical remission (BR), gross total resection (GTR), and intraoperative cerebrospinal fluid (CSF) leaks are important metrics in transsphenoidal surgery for acromegaly, and prediction of their likelihood using machine learning would be clinically advantageous. We aim to develop and externally validate clinical prediction models for outcomes after transsphenoidal surgery for acromegaly.

METHODS

Using data from two registries, we develop and externally validate machine learning models for GTR, BR, and CSF leaks after endoscopic transsphenoidal surgery in acromegalic patients. For the model development a registry from Bologna, Italy was used. External validation was then performed using data from Zurich, Switzerland. Gender, age, prior surgery, as well as Hardy and Knosp classification were used as input features. Discrimination and calibration metrics were assessed.

RESULTS

The derivation cohort consisted of 307 patients (43.3% male; mean [SD] age, 47.2 [12.7] years). GTR was achieved in 226 (73.6%) and BR in 245 (79.8%) patients. In the external validation cohort with 46 patients, 31 (75.6%) achieved GTR and 31 (77.5%) achieved BR. Area under the curve (AUC) at external validation was 0.75 (95% confidence interval: 0.59-0.88) for GTR, 0.63 (0.40-0.82) for BR, as well as 0.77 (0.62-0.91) for intraoperative CSF leaks. While prior surgery was the most important variable for prediction of GTR, age, and Hardy grading contributed most to the predictions of BR and CSF leaks, respectively.

CONCLUSIONS

Gross total resection, biochemical remission, and CSF leaks remain hard to predict, but machine learning offers potential in helping to tailor surgical therapy. We demonstrate the feasibility of developing and externally validating clinical prediction models for these outcomes after surgery for acromegaly and lay the groundwork for development of a multicenter model with more robust generalization.

First but not second postoperative day growth hormone assessments as early predictive tests for long-term acromegaly persistence

PURPOSE

Postoperative assessment of acromegaly activity is typically performed at least 3 months after neurosurgery (NS). Few studies have evaluated the use of early postoperative growth hormone (GH) levels as a test to predict short- and long-term remission of acromegaly. Our objective was to evaluate the diagnostic performance of serum random GH on a postoperative day one (D1-rGH) and two (D2-rGH), particularly in predicting long-term disease persistence.

MATERIALS AND METHODS

Forty-one subjects with acromegaly who were undergoing NS were enrolled (mean age ± SD 47.4 ± 13.1 years at diagnosis; women 54%; macroadenomas 71%). The final assessment of disease activity was performed one year after NS. ROC curves were used to evaluate the diagnostic performance of D1-rGH and D2-rGH.

RESULTS

After a 1-year follow-up, the overall remission rate was 55%. ROC analysis identified an optimal D1-rGH cut-off value of 2.1 ng/mL for diagnosing long-term disease persistence (55.6% SE; 90.9% SP). The cut-off point became 2.5 ng/mL after maximizing specificity for disease persistence (yielding a 100% positive predictive value) and 0.3 ng/mL after maximizing sensitivity for disease remission. The optimal D2-rGH cut-off value was 0.6 ng/mL (81.8% SE; 50% SP); the cut-off point became 2.9 ng/mL after maximizing specificity and 0.1 ng/mL after maximizing sensitivity, with no clinical utility.

CONCLUSIONS

D1-rGH could be a highly specific test for the early diagnosis of long-term acromegaly persistence, which is predicted by a value > 2.5 ng/mL with a great degree of certainty. The diagnostic performance of D2-rGH was insufficient. Further research is required to validate these preliminary results prior to modifying the postoperative management of acromegaly.

2010 versus the 2000 consensus criteria in patients with normalised insulin-like growth factor 1 after transsphenoidal surgery has high predictive values for long-term recurrence-free survival in acromegaly

The present study investigated the factors associated with recurrence during long-term follow-up in acromegaly and compared the recurrence rate between patients in remission with 2010 vs 2000 consensus criteria. We retrospectively recruited 133 adult acromegalic patients who had undergone transsphenoidal surgery (TSS) from January 2013 to December 2014 and assessed their clinical characteristics, surgical outcomes and recurrence. Surgical remission was defined as normalised insulin-like growth factor 1 (IGF-1) with nadir growth hormone (GH) during an oral glucose tolerance test (OGTT) < 1 μg/ L no less than 3 months after TSS without adjuvant therapy. Recurrence was defined as persistently reelevated IGF-1 after surgical remission. Cox regression analysis and Kaplan-Meier survival analysis were performed to evaluate the factors associated with recurrence. Remission was achieved in 77 cases (57.9%) after TSS alone. Recurrence was seen in five cases (6.5%) at 12, 12, 12, 36 and 54 months, respectively, after surgery. Cox regression analysis showed that a nadir GH < 0.4 μg /L (vs 0.4-1.0 μg /L) at surgical remission (odds ratio [OR] = 0.106; 95% confidence interval [CI] = 0.017-0.645; P = 0.015) and Ki-67 index (OR = 2.636; 95% CI = 1.023-6.791; P = 0.045) were independent factors influencing recurrence. Kaplan-Meier survival analysis showed that the median recurrence-free survival was 36 months (95% CI = 20-52) for patients with nadir GH 0.4-1.0 μg /L at surgical remission. The median recurrence-free survival for patients with nadir GH < 0.4 μg /L at surgical remission was much longer (ie, required further follow-up to estimate). A failure of GH suppression under 0.4 μg /L during an OGTT in patients with normalised IGF-1 and a higher Ki-67 index are independent predictors of recurrence after surgical remission in GH-secreting pituitary adenomas. Compared to patients with nadir GH < 0.4 μg /L, those with nadir GH 0.4-1.0 μg /L appear to have a significantly higher risk of recurrence.

Prognostic factors of biochemical remission after transsphenoidal surgery for acromegaly: a structured review

PURPOSE

Biochemical control is the main determinant of survival, clinical manifestations and comorbidities in acromegaly. Transsphenoidal selective adenomectomy (TSA) is the initial treatment of choice with reported biochemical remission rates varying between 32 and 85%. Understanding the limiting factors is essential for identification of patients who require medical treatment.

METHODS

We reviewed the English literature published in Medline/Pubmed until Dec 31, 2019 to identify eligible studies that described outcomes of TSA as primary therapy and performed analyses to determine the main predictors of remission.

RESULTS

Most publications reported single-institution, retrospective studies. The following preoperative parameters were consistently associated with lower remission rates: cavernous sinus invasion by imaging, larger tumor size and higher GH levels. Young age and preoperative IGF-1 levels were predictive in some studies. When controlled for covariates, the best single preoperative predictor was cavernous sinus invasion, followed by preoperative GH levels. Conversely, low GH level in the first few days postoperatively was a robust predictor of durable remission. The influence of tumor histology (sparsely granular pattern, co-expression of prolactin and proliferation markers) on surgical remission remains to be established. Few studies developed predictive models that yielded much higher predictive values than individual parameters.

CONCLUSION

Surgical outcome prognostication systems could be further generated by machine learning algorithms in order to support development and implementation of personalized care in patients with acromegaly.

A follow-up study on outcomes of endoscopic transsphenoidal approach for acromegaly

OBJECTIVE

A thorough follow-up study in which the same clinic presents the change in the surgical outcomes of acromegaly over the years, is still lacking in the endoscopic era. In this study, we intended to evaluate the clinical characteristics, radiological features, surgical and late remission rates of newly diagnosed acromegaly patients treated in our clinic between 2014 and 2019 in order to delineate the surgical remission status according to radiological, microscopic, and hormonal features. As a follow-up to our initial report, we also aimed to display the change of surgical remission rates over time in a tertiary center.

METHODS

A total of newly diagnosed 106 patients with acromegaly, who underwent endoscopic endonasal trans-sphenoidal approach (EETSA) in the last five years were retrospectively analyzed and presented in this study. Medical records were reviewed in clinical, biochemical, pathological, and radiological aspects to assess the relationship of preoperative patient characteristics with surgical remissions.

RESULTS

The percentages of the giant pituitary adenomas (≥4 cm), adenomas with suprasellar extension and adenomas with surgically proven invasion of the cavernous sinus in the present series were 13%, 34%, and 20%, respectively. Gross total resection was achieved in 80% of the patients. Surgical remission and late remission rates were 66% and 86%, respectively. Nine (9.4%) patients in our current report had postoperative transient diabetes insipidus. The mean follow-up period in this series was 36.1 ± 18.1 (range 12-59) months.

CONCLUSION

The presented surgical results are considerably better than our published initial series of acromegaly patients operated in the same clinic between 2007 and 2014. The improvement in surgical remission rate support a positive surgical volume - remission rate relationship for acromegaly in the era of endoscopic endonasal skull base approaches. One possible factor for better results may be the increasing surgical experience in EETSA, which follows a trend toward gradual improvement of long-term late remissions via a multidisciplinary approach.

Surgical management of growth hormone-secreting pituitary adenomas: A retrospective analysis of 33 patients

The endoscopic endonasal transsphenoidal approach (EETA) is the primary treatment for growth hormone (GH) adenoma. This study aimed to investigate the outcomes of EETA in 33 patients with GH-secreting pituitary adenoma (PA).Thirty-three patients who underwent EETA in Eighth People's Hospital of Shenzhen between January 2013 and December 2017 were included in the comprehensive analysis. Factors affecting the extent of resection and postoperative remission rates were also reviewed.The total cut rate was 63.6% (21), and the total remission rate was 66.7% (22) in all patients after surgery. The cure rate was 60.6% (20) for 33 patients. The total removal rate and remission rate were significantly different (P = .01, P = .007) for microadenomas, macroadenomas, and giant adenomas. In addition, the total removal rate and remission rate were significantly different (P = .004, P = .007) for patients with noninvasive and invasive GH-secreting PAs. Furthermore, there were significant differences (P = .003, P = .005) in the total removal rate and remission rate of patients with different preoperative GH levels. All patients with hypertension and diabetes mellitus were normalized. Three patients exhibited recurrence after surgery. Several patients suffered from postoperative complications, including transient diabetes insipidus in 3 (9.1%) patients and postoperative transient cerebrospinal fluid leakage in 2 (6.1%) patients.EETA is an effective therapeutic approach for treating patients with GH-secreting PA with high remission and low complication rates. Therefore, EETA should be considered a primary treatment for patients with GH-secreting PA.

Evaluation of Complications and Costs During Overlapping Transsphenoidal Surgery in the Treatment of Pituitary Adenoma

BACKGROUND

Pituitary adenomas are among the most common primary brain tumors. Recently, overlapping surgery has been curbed in many institutions because of the suggestion there might be more significant adverse events, despite several studies showing that complication rates are equivalent.

OBJECTIVE

To assess complications and costs associated with overlapping surgery during the transsphenoidal resection of pituitary adenomas.

METHODS

A single-center, retrospective cohort study was performed to evaluate the cases of patients who underwent a transsphenoidal approach for pituitary tumor resection. Patient, surgical, complication, and cost (value-driven outcome) variables were analyzed.

RESULTS

A total of 629 patients (302 nonoverlapping, 327 overlapping cases) were identified. No significant differences in age (P = .6), sex (P = .5), tumor type (P = .5), or prior rates of pituitary adenoma resection (P = .5) were seen. Similar presenting symptoms were observed in the 2 groups, and follow-up length was comparable (P = .3). No differences in tumor sizes (P = .5), operative time (P = .4), fat/fascia use (P = .4), or cerebrospinal fluid diversion (P = .8) were seen between groups. The gross total resection rate was not significantly different (P = .9), and no difference in recurrence rate was seen (P = .4). A comparable complication rate was seen between groups (P = .6). No differences in total or subtotal costs were seen either.

CONCLUSION

The results of this study offer additional evidence that overlapping surgery does not result in worsened complications, lengthened surgery, or increased patient cost for patients undergoing transsphenoidal resection of pituitary adenomas. Thus, studies and policy aiming to improve patient safety and cost should focus on optimizing other aspects of healthcare delivery.

[Evaluation of transsphenoidal adenomectomy outcomes in acromegaly using different remission criteria]

For a long time, surgical removal of somatotropinoma using the transsphenoidal approach has been the first stage of treatment in most acromegaly patients. For the past decades, the efficacy criteria for surgical treatment of acromegaly have significantly changed, which requires appropriate correction.

PURPOSE

We aimed to evaluate the results of transsphenoidal adenomectomy in acromegaly patients using various criteria for disease remission.

MATERIAL AND METHODS

The study included patients with newly diagnosed acromegaly who underwent transnasal transsphenoidal endoscopic adenomectomy performed by a single neurosurgeon. The surgical treatment outcomes were evaluated 6 months after operative intervention based on levels of IGF-1, OGTT, and GH. The obtained data were analyzed using different threshold values for the level of GH nadir during OGTT: criteria A <2.0 ng/ml, criteria B <1.0 ng/ml, and criteria C <0.4 ng/ml to assess acromegaly remission, along with matching of the IGF-1 level to the reference range for a given gender and age.

RESULTS

The study included 70 patients (52 females and 18 males) with a mean age of 52.2±11.5 years (29 to 73 years). The baseline IGF-1 level exceeded the upper limit of the reference range 3.3±1.4 (1.1-7.3)-fold, on average. The baseline mean basal GH level was 34.2±41.7 (1.2-192.0) ng/ml. The mean pituitary adenoma size was 16.7±8.6 (4.3-46.0) mm; 18 (26%) out of 70 patients had pituitary microadenoma, and 52 (74%) patients had macroadenoma. Six months after surgery, acromegaly remission met criteria A in 47 (67%) patients, criteria B in 28 (40%) patients, and criteria C in 18 (26%) patients.

CONCLUSION

Our findings demonstrate that evaluation of transsphenoidal adenomectomy outcomes in treatment of acromegaly patients depends on the criteria chosen for assessing remission. This feature should be considered when comparing outcomes of surgical treatment for acromegaly in different years. Probably, introduction of the 2010 criteria should be accompanied by revision of the previous remission indicators.

Predictors of surgical outcome and early criteria of remission in acromegaly

BACKGROUND

Transsphenoidal surgery (TSS) is the cornerstone of acromegaly treatment, however there are no robust predictors of surgical outcome and remission can only be defined three months after surgery.

PURPOSE

To analyze if biochemical, demographical, radiological, and immunohistochemical characteristics are predictors of surgical remission and investigate if immediate postoperative GH and IGF-I levels can help defining remission earlier.

METHODS

Consecutive acromegaly patients submitted to TSS between 2013-2016 were evaluated. Remission criteria was defined as normal IGF-I and GH <1 mcg/L three months after surgery. Data of age, sex, GH and IGF-I levels, tumor volume, cavernous sinus invasion, T2-weighted signal, Ki-67, and granulation pattern were correlated with remission status. GH and IGF-I levels at 24, 48 h, and one week postoperative were evaluated as early criteria of remission.

RESULTS

Sixty-nine patients were included (84% macroadenomas) and surgical remission was achieved in 45%. No difference between cured and not cured patients concerning age, gender, preoperative GH or IGF-I levels, tumor volume, T2-weighted signal, Ki-67 and tumor granularity was observed. Remission was obtained in 20 of 36 (56%) of the non-invasive tumors, and in 3 of 16 (19%) of the invasive tumors (p = 0.017). A GH <1.57 mcg/L 48 h after surgery was able to predict remission with 93% sensitivity and 86% specificity and an IGF-I < 231% ULNR one week after surgery predicted remission with 86% sensitivity and 93% specificity.

CONCLUSION

Cavernous sinus invasion is the only preoperative predictor of surgical remission. GH at 48 h and IGF-I one week after surgery can define earlier not cured patients.

Microsurgical versus endoscopic transsphenoidal resection for acromegaly: a systematic review of outcomes and complications

PURPOSE

The aim of this systematic review is to evaluate the long-term endocrine outcomes and postoperative complications following endoscopic vs. microscopic transsphenoidal resection (TSR) for the treatment of acromegaly.

METHODS

A literature review was performed, and studies with at least five patients who underwent TSR for acromegaly, reporting biochemical remission criteria and long-term remission outcomes were included. Data extracted from each study included surgical technique, perioperative complications, biochemical remission criteria, and long-term remission outcomes.

RESULTS

Fifty-two case series from 1976 to 2016 met the inclusion criteria, comprising 4375 patients. Thirty-six reports were microsurgical (n = 3144) and 13 were endoscopic (n = 940). Three studies compared microsurgical (n = 111) to endoscopic TSR outcomes (n = 180). The overall initial and long-term remission rates were 58.2 vs. 57.4% and 69.2 vs. 70.2% for the microsurgical and endoscopic groups, respectively. For microadenomas, the initial and long-term remission rates were 77.6 vs. 82.2% and 76.9 vs. 73.5% for microsurgical and endoscopic approaches, respectively. For macroadenomas, the initial and long-term remission rates were 46.9 vs. 60.0% and 40.2 vs. 61.5% for microsurgical and endoscopic approaches, respectively. The rates of postoperative CSF leak were 3.0 vs. 2.3% for the microscopic and endoscopic groups, respectively. The rates of hypopituitarism and transient diabetes insipidus were 6.7 vs. 6.4% and 9.0 vs. 7.8% for the microscopic and endoscopic groups, respectively.

CONCLUSIONS

Both endoscopic and microsurgical approaches for TSR of growth hormone-secreting adenomas are viable treatment options for patients with acromegaly, and yield similarly high rates of remission under the most current consensus criteria.

Three-Dimensional Endoscopic Endonasal Approach and Outcomes in Sellar Lesions: A Single-Center Experience of 104 Cases

BACKGROUND

Pituitary tumors account for approximately 15% of primary intracranial neoplasms and often are diagnosed incidentally. Common sellar lesions are pituitary adenomas, craniopharyngiomas, and Rathke cleft cysts. Currently endoscopic transsphenoidal approaches are largely used, and many centers also use 3-dimensional (3D) technology, although additional results of long-term follow-up are still being accumulated.

METHODS

We present a retrospective analysis of 104 patients with sellar lesions (57 male and 47 female, mean age 52 years) who underwent 3D endoscopic transsphenoidal surgery in our center from December 2011 to March 2015 and were followed up for a mean time of 18 months.

RESULTS

A total of 16 patients were diagnosed with growth hormone-secreting adenomas, 9 with adrenocorticotropic hormone-secreting, 5 with prolactin-secreting, and 2 with thyroid-stimulating hormone-secreting tumors and 58 with nonsecreting pituitary adenomas. Five patients had Rathke cleft cysts, 5 craniopharyngiomas, 2 fibrous solitary tumors, 1 a metastasis, and 1 a chordoma. At baseline, 47 patients (45.2%) had hormonal changes and 52 (50%) had visual field changes. Complete resection was achieved in 73 patients (70.1%). Follow-up evaluation detected hormonal remission in 7 patients with Cushing disease (77.7%) and in 11 patients with acromegaly (68.7%). Complications were cerebrospinal fluid leak in 5 cases (4.8%) and transient diabetes insipidus in 6 cases (5.7%). A total of 55 patients (52.9%) were discharged less than 72 hours after surgery.

CONCLUSIONS

The use of an endoscopic endonasal approach with 3D technology provides several advantages relating to patient length of stay, rate of complications, postoperative recovery, and novice surgeons' training. Advantages of 3D endoscopy and long-term follow-up still need further elucidation.

60 YEARS OF NEUROENDOCRINOLOGY: Acromegaly

Acromegaly (ACM) is a chronic, progressive disorder caused by the persistent hypersecretion of GH, in the vast majority of cases secreted by a pituitary adenoma. The consequent increase in IGF1 (a GH-induced liver protein) is responsible for most clinical features and for the systemic complications associated with increased mortality. The clinical diagnosis, based on symptoms related to GH excess or the presence of a pituitary mass, is often delayed many years because of the slow progression of the disease. Initial testing relies on measuring the serum IGF1 concentration. The oral glucose tolerance test with concomitant GH measurement is the gold-standard diagnostic test. The therapeutic options for ACM are surgery, medical treatment, and radiotherapy (RT). The outcome of surgery is very good for microadenomas (80-90% cure rate), but at least half of the macroadenomas (most frequently encountered in ACM patients) are not cured surgically. Somatostatin analogs are mainly indicated after surgical failure. Currently their routine use as primary therapy is not recommended. Dopamine agonists are useful in a minority of cases. Pegvisomant is indicated for patients refractory to surgery and other medical treatments. RT is employed sparingly, in cases of persistent disease activity despite other treatments, due to its long-term side effects. With complex, combined treatment, at least three-quarters of the cases are controlled according to current criteria. With proper control of the disease, the specific complications are partially improved and the mortality rate is close to that of the background population.

Endoscopic endonasal transsphenoidal surgery: implementation of an operative and perioperative checklist

Endoscopic endonasal surgery relies heavily on specialized operative instrumentation and optimization of endocrinological and other critical adjunctive intraoperative factors. Several studies and worldwide initiatives have previously established that intraoperative and perioperative surgical checklists can minimize the incidence of and prevent adverse events. The aim of this article was to outline some of the most common considerations in the perioperative and intraoperative preparation for endoscopic endonasal transsphenoidal surgery. The authors implemented and prospectively evaluated a customized checklist at their institution in 25 endoscopic endonasal operations for a variety of sellar and skull base pathological entities. Although no major errors were detected, near misses pertaining primarily to missing components of surgical equipment or instruments were identified in 9 cases (36%). The considerations in the checklist provided in this article can serve as a basic template for further customization by centers performing endoscopic endonasal surgery, where their application may reduce the incidence of adverse or preventable errors associated with surgical treatment of sellar and skull base lesions.

Clinical factors involved in the recurrence of pituitary adenomas after surgical remission: a structured review and meta-analysis

To study the currently available data of recurrence rates of functioning and nonfunctioning pituitary adenomas following surgical cure and to analyze associated predisposing factors, which are not well established. A systematic literature search was conducted using Medline, Embase, Web of Science and the Cochran Library for studies reporting data on recurrence of pituitary adenoma after surgery, in nonfunctioning adenoma (NF), prolactinoma (PRL) acromegaly (ACRO) and Cushing's disease (CUSH). Of 557 initially retrieved potential relevant studies 143 were selected. Recurrence in NFA was defined as reappearance of tumor on MRI or CT. Increase of hormone levels above normal limits as set by the authors after initial remission was used to indicate recurrence in the functioning tumor types. Remission percentage was lowest in NFA compared with other tumor types (P < 0.001). Surgery-related hypopituitarism was more frequent in CUSH than in the other tumors (P < 0.001). Recurrence, expressed as percentage of the cured population or as ratio of recurrence and total patient years of follow-up was highest in PRL (P < 0.001). The remission percentage did not improve over 3 decades of publications, but there was a modest decrease in recurrence rate (P = 0.04). Recurrences peaked between 1 and 5 years after surgery. Most of the studies with a sufficient number of recurrences did not apply multivariate statistics, and mentioned at best associated factors. Age, gender, tumor size and invasion were generally unrelated to recurrence. For functioning adenomas a low postoperative hormone concentration was a prognostically favorable factor. In NFA no specific factor predicted recurrence. Recurrence rate differs between pituitary adenomas, being highest in patients with prolactinoma, with the highest incidence of recurrence between 1 and 5 years after surgery in all adenomas. Patients with NFA have a lower chance of remission than patients with functioning adenomas. The postoperative basal hormone level is the most important predictor for recurrence in functioning adenomas, while in NFA no single convincing factor could be identified.

Surgery and radiosurgery for acromegaly: a review of indications, operative techniques, outcomes, and complications

Among multimodality treatments for acromegaly, the goals of surgical intervention are to balance maximal tumor resection while preserving normal pituitary function and maintaining patient safety. The resection of growth hormone-(GH-) secreting pituitary adenomas in the hands of experienced surgeons results in hormonal remission in 50-70% of patients. Acromegalic patients often have medical comorbidities and anatomical variations complicating anesthesia and surgical management. Despite these challenges, complications such as CSF leak or new hypopituitarism following surgery remain uncommon. Over the past decade, endoscopic approaches to pituitary tumors have improved visualization and facilitated identification of additional tumor using angled telescopes. Patients with persistent acromegaly following surgery require continued medical and/or radiation-based interventions. The adjunctive use of stereotactic radiosurgery offers hormonal remission in 40-50% of patients. In this article, the current preoperative evaluation, indications for surgery, surgical approaches, role of radiosurgery, complications, and remission criteria following operative resection of GH adenomas are reviewed.

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.

Radiation treatment strategies for acromegaly

The high morbidity and mortality associated with acromegaly can be addressed with multiple treatment modalities, including surgery, medicines, and radiation therapy. Radiation was initially delivered through conventional fractionated radiotherapy, which targets a wide area over many treatment sessions and has been shown to induce remission in 50%&#x2013;60% of patients with acromegaly. However, conventional fractionated radiotherapy takes several years to achieve remission in patients with acromegaly and carries a risk of hypopituitarism that may limit its use. Stereotactic radiosurgery, of which there are several forms, including Gamma Knife surgery, CyberKnife therapy, and proton beam therapy, offers slightly attenuated efficacy but achieves remission in less time and provides more precise targeting of the adenoma with better control of the dose of radiation received by adjacent structures such as the pituitary stalk, pituitary gland, optic chiasm, and cranial nerves in the cavernous sinus. Of the forms of stereotactic radiosurgery, Gamma Knife surgery is the most widely used and, because of its long-term follow-up in clinical studies, is the most likely to compete with medical therapy for first-line adjuvant use after resection. In this review, the authors outline the major modes of radiation therapies in clinical use today, and they critically assess the feasibility of these modalities for acromegaly treatment. Acromegaly is a multisystem disorder that demands highly specialized treatment protocols including neurosurgical and endocrinological intervention. As more efficient forms of pituitary radiation develop, acromegaly treatment options may continue to change with radiation therapies playing a more prominent role.

Significance of postoperative fluid diuresis in patients undergoing transsphenoidal surgery for growth hormone–secreting pituitary adenomas

Object

Following successful transsphenoidal surgery in patients with growth hormone (GH)–secreting pituitary adenomas, a characteristic fluid diuresis has been described. In this paper the authors aimed to further analyze the degree of fluid diuresis as it relates to postoperative GH levels.

Methods

Between 2000 and 2008, 85 patients underwent transsphenoidal surgery for a GH-secreting adenoma at the USC University Hospital. A retrospective chart review was conducted. Postoperative fluid intake, output, and balance within 48 hours following surgery, as well as endocrinological data were recorded and analyzed. Patients with postoperative diabetes insipidus and those with insufficient data were excluded from analysis.

Results

Seventy-one patients were included in the analysis. The mean age was 46 years (range 16–74 years). There were 36 males (51%) and 35 females (49%). Patients with negative fluid balances at 48 hours after surgery were more than twice as likely to have a GH level of < 1.5 ng/ml (55 vs 25%, p = 0.023). At 48 hours after surgery, patients with a negative overall fluid balance had a significantly lower median GH level than those with a positive overall fluid balance (1.3 vs 2.4 ng/ml, p = 0.039). This difference was even more pronounced in patients with microadenomas and a negative overall fluid balance. By 48 hours following surgery, patients with postoperative Day 1 GH levels < 1.5 ng/ml had, on average, experienced diuresis of fluid > 1.1 L (median 1.5 L) more than patients with GH levels > 1.5 ng/ml.

Conclusions

Successful resection of GH-secreting adenomas is associated with a more pronounced fluid diuresis and negative overall fluid balance within 48 hours following transsphenoidal surgery. Patients with a negative fluid balance by postoperative Day 2 have a higher likelihood of having significantly reduced postoperative GH levels that may correlate with long-term surgical remission.

Endoscopic pituitary surgery: a systematic review and meta-analysis

Object

Surgery on the pituitary gland is increasingly being performed through an endoscopic approach. However, there is little published data on its safety and relative advantages over traditional microscope-based approaches. Published reports are limited by small sample size and nonrandomized study design. A meta-analysis allows for a description of the impact of endoscopic surgery on short-term outcomes.

Methods

The authors performed retrospective review of data from their institution as well as a systematic review of the literature. The pooled data were analyzed for descriptive statistics on short-term outcomes.

Results

Nine studies (821 patients) met inclusion criteria. Overall, the pooled rate of gross tumor removal was 78% (95% CI 67–89%). Hormone resolution was achieved in 81% (95% CI 71–91%) of adrenocorticotropic hormone secreting tumors, 84% (95% CI 76–92%) of growth hormone secreting tumors, and 82% (95% CI 70–94%) of prolactin secreting tumors. The pooled complication rates were 2% (95% CI 0–4%) for CSF leak and 1% (95% CI 0–2%) for permanent diabetes insipidus. There were 2 deaths reported in the literature that were both related to vascular injury, giving an overall mortality rate of 0.24%.

Conclusions

The results of this meta-analysis support the safety and short-term efficacy of endoscopic pituitary surgery. Future studies with long-term follow-up are required to determine tumor control.

Radiotherapy and radiosurgery in acromegaly

Growth-hormone hypersecretion, acromegaly, is associated with reduced life expectancy. First line treatment remains surgery, but remission rates vary between 50% and 90%. In case of lack of surgical remission or recurrence, somatostatin agonists can be proposed. However, about 30% of patients are partially or totally resistant to this treatment. The growth hormone receptor antagonist pegvisomant currently needs more prolonged follow-up studies. Conventional radiotherapy and radiosurgery are two radiation treatment modalities that can be proposed to these resistant patients. Reported rates of remission for conventional radiotherapy range between 50% and 60% in patients with acromegaly, with a time to remission delayed by several years, and adverse effects including high rates of hypopituitarism. This treatment could be proposed to patients with aggressive adenomas, in whom surgery cannot allow biochemical control. In contrast, studies on stereotactic radiosurgery reported lower rates of remission, with faster growth hormone hypersecretion decline, and a lower risk of adverse effects. However, this latter technique requires a well defined target volume, which limits its indications. The high precision of this technique makes it possible to be used as an alternative primary treatment to surgery. We reviewed major advantages and drawbacks of each of these techniques, based on recent studies to try to define their respective indications in the therapeutic algorithm of acromegaly.

The endonasal microscopic approach for pituitary adenomas and other parasellar tumors: a 10-year experience

THE DIRECT ENDONASAL transsphenoidal approach to the sella with the operating microscope was initially described more than 20 years ago. Herein, we describe the technique, its evolution, and lessons learned over a 10-year period for treating pituitary adenomas and other parasellar pathology. From July 1998 to January 2008, 812 patients underwent a total of 881 operations for a pituitary adenoma (n = 605), Rathke's cleft cyst (n = 59), craniopharyngioma (n = 26), parasellar meningioma (n = 23), chordoma (n = 18), or other pathological condition (n = 81). Of these, 118 operations (13%) included an extended approach to the suprasellar, infrasellar/clival, or cavernous sinus regions. Endoscopic assistance was used in 163 cases (19%) overall, including 36% of the last 200 cases in the series and 18 (72%) of the last 25 extended endonasal cases. Surgical complications included 19 postoperative cerebrospinal fluid leaks (2%), 6 postoperative hematomas (0.7%), 4 carotid artery injuries (0.4%), 4 new permanent neurological deficits (0.4%), 3 cases of bacterial meningitis (0.3%), and 2 deaths (0.2%). The overall complication rate was higher in the first 500 cases in the series and in extended approach cases. Major technical modifications over the 10-year period included increased use of shorter (60-70 mm) endonasal speculums for greater instrument maneuverability and visualization, the micro-Doppler probe for cavernous carotid artery localization, endoscopy for more panoramic visualization, and a graded cerebrospinal fluid leak repair protocol. These changes appear to have collectively and incrementally made the approach safer and more effective. In summary, the endonasal approach provides a minimally invasive route for removal of pituitary adenomas and other parasellar tumors.

Outcome of surgical intrasellar growth hormone tumor performed by a pituitary specialist surgeon in a developing country

BACKGROUND

Acromegaly is an excessive GH secretion, which in most cases, is caused by a pituitary GH-secreting adenoma. Traditional treatment of acromegaly consists of surgery, drug therapy, and eventually radiotherapy. The aim of this retrospective study is to evaluate the results of transsphenoidal endoscopic surgery in a group of patients with intrasellar GH adenoma who were operated by a pituitary specialist surgeon. We shall then argue about the economical advantages, for the NHS of a developing country, between surgical and medical treatment.

METHODS

We have analyzed data from 33 patients with intrasellar GH tumor who had been referred to the neuroendocrine department of the HGF, Brazil. The patients underwent a transsphenoidal endoscopic adenomectomy for acromegaly between 2000 and 2005. Their ages were between 20 and 67 years (mean, 44 years) at the moment of surgery. No cavernous sinus invasion was present. Follow-up was a median of 2 years (range, 12 months-6 years).

RESULTS

All 33 patients had intrasellar adenoma, 84.84% of patients achieved remission by surgery. One patient was operated twice and reached hormonal normalization. Five patients still had the disease and refused a second surgery. A treatment with octreotide was started for these 5 patients and resulted in an adequate control of GH and IGF-1 levels. No patients had radiotherapy.

CONCLUSION

Our patients, with intrasellar GH tumor, operated by a pituitary specialist neurosurgeon had remission rates approaching those obtained by most specialized neurosurgical centers worldwide. For equal results, our study shows that the surgical treatment is the best issue for the patient and for the NHS.

Transsphenoidal surgery

Transsphenoidal surgery has evolved much over nearly 100 years. Initially operations were performed often without any input from endocrinology colleagues, and without preoperative imaging, operative magnification and illumination. Advances in the understanding of the biology of pituitary tumours, close co-operation between endocrinologists, surgeons and oncologists, and huge advances in imaging and surgical techniques have led to the evolution of the current transsphenoidal operation to the pituitary fossa to the point where a 'cure' is often possible with low complication rates. The indications, contraindications of transsphenoidal surgery will be discussed, together with nature of the surgical approach and how it can be applied to particular pituitary tumours and suprasellar lesions.

A prospective analysis of 151 cases of patients with acromegaly operated by one neurosurgeon: a follow-up of more than 23 years

BACKGROUND

Transsphenoidal adenomectomy has been the accepted surgical management for treatment of growth hormone (GH)-secreting pituitary adenomas. Although the goal of treatment might be to keep the GH level in the reference range, the actual definition of success in control of acromegaly is not yet clear.

METHODS

The aim of this study was to analyze prospectively the result of transsphenoidal adenoctomy performed over 23-year period by a single neurosurgeon in one center. The analysis has been performed to determine which preoperative factor could significantly influence the long term outcome. This series consisted of 151 patients. The preoperative hormonal studies documenting the high GH and/or insulin-like growth factor were available in all the cases. At least 1 laboratory report documenting the postoperative level of hormones was also available for all of them. Transsphenoidal microsurgical adenomectomy was performed in all the cases.

RESULTS

There were 90 patients with pure GH-secreting adenoma (59.6%) with the highest GH level of 235 mU/L. A second group of 12 patients had normal GH level but elevated serum level of insulin-like growth factor 1 (8%). The group with mixed secretion of GH and prolactin included 49 cases (32.4%). There was no postoperative mortality. Cerebrospinal fluid leakage occurred in 12 patients. Transient diabetes insipidus was encountered in 19 cases (12.6%) and long lasting diabetes insipidus in 2 patients (1.3%). Early and minor hypopituitarism was encountered in 14 patients, whereas a persistent condition occurred mainly after irradiation in 14 other cases. Normal postoperative serum GH level could be achieved in 98 patients (94.2%) of 104 cases with full follow-up.

CONCLUSION

In the developing countries, early diagnosis and proper surgical extirpation of the GH-secreting adenoma by an experienced and dedicated pituitary surgeon is mandatory to reduce the mortality and increase the chance of cure of this rather mortal endocrionopathy.

The endoscopic versus the traditional approach in pituitary surgery

The transsphenoidal route is the most widely used technique for pituitary adenoma surgery due to its rapidity, good tolerance, effectiveness and low complication rate. These are the parameters we utilized in comparing endoscopic with microscopic transsphenoidal surgery. We reviewed the medical records of 418 patients affected by pituitary adenomas who underwent endoscopic transsphenoidal surgery between May 1998 and December 2004, and in this paper, we present the results of 381 patients who fulfilled the follow-up criteria after a minimum period of 15 months. Our experience confirms the previous data on the rapidity and satisfactory tolerance of the endoscopic procedure. We also confirm the low complication rate, specifying that complications characteristic of the approaching phase were certainly reduced; instead, complications characteristic of tumor removal still remained similar to those reported in the microsurgical literature. The results were comparable with those of the best microsurgical series regarding endosellar lesions, but tumor removal was notably superior when dealing with tumors having an extrasellar extension. The improvement may be explained by the excellent vision of the deep surgical fields due to the endoscope and by the extreme flexibility of the surgical trajectory, mainly due to the absence of the divaricator, giving access to the ramifications of the tumor, otherwise difficult to reach.