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

Unravelling pituitary tumours in medically treated patients with acromegaly: the impact of systematic MRI reassessment

BACKGROUND

In acromegaly, the primary tumor is usually found during magnetic resonance imaging (MRI) of the pituitary gland. A remnant tumor after surgery is, however, harder to depict. When a tumor is missed, the remaining option is usually lifelong pharmacological treatment.

PURPOSE

To identify tumors by reassessment of all available MRI scans in pharmacologically treated patients, operated or not, and to compare our results with the routine MRI reports.

MATERIAL AND METHODS

Adult patients diagnosed with acromegaly and managed at a tertiary care center between 2005 and 2021 and currently on pharmacological treatment were included. MRI scans were evaluated in a standardized manner and classified independently by a radiologist and an endocrinologist into "certain," "suspected," or "no tumor." In case of disagreement, consensus was achieved with a senior neuroradiologist. The results were compared using the clinical radiologists' routine MRI reports.

RESULTS

We identified certain and suspected tumors in 29/74 and 36/74 patients, respectively. No tumor was identified in nine patients. In five of these, no MRI contrast agent was given. Discrepancy between our results and the routine MRI reports was found in 31/74 patients (P = 0.01). In 22 patients, the routine reports described no tumor while we identified certain tumors in 2/22 patients and suspected tumors in 13/22 patients.

CONCLUSION

In most patients with pharmacologically treated acromegaly, we identified a certain or suspected pituitary tumor. These findings were more frequent compared to the routine MRI reports. Based on our results, patients will be considered for a change in long-term treatment modality.

Changing presentation of acromegaly in half a century: a single-center experience

OBJECTIVE

Investigate the changes in the characteristics of presentation, in patients with acromegaly over a period of approximately half a century.

METHODS

The medical records of patients diagnosed with acromegaly between 1980 and 2023 were retrospectively reviewed. The collected data were examined to assess any changes observed over the years and a comparison was made between the characteristics of patients diagnosed in the last decade and those diagnosed in previous years.

RESULTS

A total of 570 patients were included in the study, 210 (37%) patients were diagnosed in the last decade. Patients diagnosed before 2014 had longer symptom duration before diagnosis, advanced age, larger pituitary adenomas, higher incidence of cavernous sinus invasion, and higher GH and IGF-1 levels than those diagnosed last decade (p < 0.05, for all). Furthermore, the patients diagnosed before 2014 had a lower rate of surgical remission (p < 0.001), and a higher prevalence of comorbidities such as diabetes, hypertension, colon polyps, and thyroid cancer at the time of diagnosis (p < 0.05, for all).

CONCLUSION

There may be a trend for earlier detection of patients with acromegaly.

Influence of gender and sexual hormones on outcomes after pituitary surgery: a systematic review and meta-analysis

BACKGROUND

Although there is an increasing body of evidence showing gender differences in various medical domains as well as presentation and biology of pituitary adenoma (PA), gender differences regarding outcome of patients who underwent transsphenoidal resection of PA are poorly understood. The aim of this study was to identify gender differences in PA surgery.

METHODS

The PubMed/MEDLINE database was searched up to April 2023 to identify eligible articles. Quality appraisal and extraction were performed in duplicate.

RESULTS

A total of 40 studies including 4989 patients were included in this systematic review and meta-analysis. Our analysis showed odds ratio of postoperative biochemical remission in males vs. females of 0.83 (95% CI 0.59-1.15, P = 0.26), odds ratio of gross total resection in male vs. female patients of 0.68 (95% CI 0.34-1.39, P = 0.30), odds ratio of postoperative diabetes insipidus in male vs. female patients of 0.40 (95% CI 0.26-0.64, P < 0.0001), and a mean difference of preoperative level of prolactin in male vs. female patients of 11.62 (95% CI - 119.04-142.27, P = 0.86).

CONCLUSIONS

There was a significantly higher rate of postoperative DI in female patients after endoscopic or microscopic transsphenoidal PA surgery, and although there was some data in isolated studies suggesting influence of gender on postoperative biochemical remission, rate of GTR, and preoperative prolactin levels, these findings could not be confirmed in this meta-analysis and demonstrated no statistically significant effect. Further research is needed and future studies concerning PA surgery should report their data by gender or sexual hormones and ideally further assess their impact on PA surgery.

Preoperative medical treatments and surgical approaches for acromegaly: A systematic review

OBJECTIVE

Acromegaly is a condition characterized by an overproduction of growth hormone which infers high morbidity and mortality if left untreated. The objective of this review is to analyse and appraise the current evidence for the generalized use of preoperative medications and the various surgical approaches as described in the literature.

DESIGN

A thorough search from MEDLINE via PubMed, EMBASE, and Cochrane Library has been performed which identified a total of 37 papers.

CONCLUSION

The preoperative use of somatostatin receptor agonists (SAs) in acromegaly is a controversial topic with current guidelines suggesting against their generalized routine use. Most authors noticed an insignificant long-term remission of acromegaly when given SAs compared with nil preoperative therapy, except for invasive macroadenomas as SAs have been found to reduce the tumour volume and aid towards the total resection of the adenoma. Furthermore, according to the evidence available, endoscopic transsphenoidal surgery is the optimum method for hypophysectomy in terms of its remission and safety profile.

Determinants of immediate and long-term remission after initial transsphenoidal surgery for acromegaly and outcome patterns during follow-up: a longitudinal study on 659 patients

OBJECTIVE

Treatment outcomes following initial transsphenoidal surgery (TSS) for acromegaly are erratic. Identifying outcome patterns can assist in informing patients about possible treatment outcomes and planning for individualized adjuvant treatments in advance. In this study, the authors aimed to investigate the immediate and long-term endocrine remission rates following initial TSS for acromegaly, identify clinical determinants of treatment outcomes, and explore outcome patterns during a long-term follow-up and the pattern-specific patient features.

METHODS

This prospective, single-center, longitudinal cohort study enrolled patients with acromegaly who underwent TSS in the period from 2015 to 2018 at the authors' institution. Immediate remission, assessed on the 2nd postoperative morning, and long-term remission, assessed at least 18 months after TSS, were evaluated according to the strict 2010 consensus criteria (random growth hormone [GH] < 1 ng/ml or GH nadir < 0.4 ng/ml after oral glucose tolerance test, and age- and sex-normalized insulin-like growth factor 1). Univariate and bivariate regression analyses were used to identify determinants of remission.

RESULTS

A total of 659 patients with acromegaly (average age 42 years, 44% males) underwent TSS for pituitary adenomas (macroadenomas, 85%; invasive tumors, 35%) and were followed up during a median of 51 months. Immediate and long-term remission rates after initial TSS were 37% and 69%, respectively. Older age at diagnosis (OR 1.7), male sex (OR 1.6), smaller tumors (OR 2.0), noninvasive tumors (OR 4.8), and tumors positive for follicle-stimulating hormone/luteinizing hormone (OR 1.5) were predictors of immediate surgical remission. In addition to the above predictors, lower preoperative GH (OR 2.4), absence of preoperative central hypothyroidism (OR 2.6), and endoscopic TSS (OR 10.6) were predictors of long-term remission. Regression analyses revealed that endoscopic TSS (OR 2.8, 95% CI 1.524-5.291, p = 0.001), absence of cavernous sinus invasion (OR 4.1, 95% CI 2.522-6.613, p < 0.001), older age (OR 1.03, 95% CI 1.006-1.048, p = 0.013), and male sex (OR 2.0, 95% CI 1.224-3.247, p = 0.006) were independent determinants of long-term remission. Five outcome patterns were identified based on the changes in hormonal results during follow-up, including continuous remission (34%), refractory acromegaly (28%), delayed remission (21%), remission after adjuvant therapy (14%), and recurrence after initial remission (3%). The clinical characteristics of each subgroup were identified.

CONCLUSIONS

Cavernous sinus invasion, age at diagnosis, and sex are the best determinants of immediate and long-term remission after initial TSS for acromegaly. Endoscopic TSS predicts a higher long-term remission rate than that with microscopic TSS. The authors identified five outcome patterns in acromegaly and group-specific patient characteristics for clinical decision-making.

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.

Pituitary adenomas

Pituitary adenomas produce a complex collection of disorders. Some are incidental findings. Some distort local anatomical structures which can lead to disorders of vision or hormone production. Some produce excesses of hormones which can be either life threatening or clinically distressing. The management requires the expertise of a variety of experts who plan together. No single treatment is universally successful in controlling these conditions. Medical, biochemical, surgical and radiosurgical management can all have parts to play. Coordinate co-operation between specialists will provide patients with the best available treatment.

T2-weighted magnetic resonance imaging as a novel predictor of surgical remission in newly diagnosed pituitary macroadenomas presenting as acromegaly

BACKGROUND

Any preoperative diagnostic assessment that can predict the success of the operation in acromegaly will provide a positive impact on overall remission rates. The aim of this study is to reveal whether the signal intensity in T2-weighted Magnetic Resonance Imaging can predict postoperative results in acromegaly patients with macroadenoma.

METHODS

We analyzed our surgical results in regard to T2-weighted images in newly diagnosed consecutive 124 patients with acromegaly, operated between 2014 and 2019. The T2-intensity of the pure somatotroph macroadenomas was correlated with the clinical, radiological, surgical and histopathological characteristics of the acromegaly patients.

RESULTS

We found a predominance of T2-hyperintensity in our series (45%) and the T2-hypointense pure somatotroph adenomas were detected in only 34% of our patients. Total resection was performed in 72% of newly diagnosed acromegaly patients in this series. Accordingly, total resection was achieved in 69% of the T2-hyperintense group, 77% of the T2-hypointense group and 69% of the T2-isointense group. The surgical remission rates for the T2-hyper-, hypo- and isointense groups were 54.5%, 80.7%, and 68.7%, respectively. The surgical remission rate in the T2-hyperintense group was significantly lower than those of hypo- and isointense groups in newly diagnosed acromegaly patients.

CONCLUSIONS

This study demonstrates a close relationship between the T2 signal intensity and the surgical remission rates in acromegaly patients with macroadenoma. Preoperative T2-intensity images may predict the probability of post-surgical remission in patients with newly diagnosed acromegaly. Further support fort this idea comes from recent guidelines for acromegaly management in which the potential utility of using T2 intensity to optimize patient management has been emphasized.

Impact of Experience on Outcomes After Endoscopic Transsphenoidal Surgery for Acromegaly

OBJECTIVE

Acromegaly is a syndrome of metabolic alterations secondary to increased growth hormone levels from a somatotroph pituitary adenoma. A multidisciplinary approach beginning with surgery, followed by adjuvant radiation or medical therapy for residual disease, is considered standard of care. Several factors affect the likelihood of remission after surgery, but the impact of surgical experience on remission rates has not been adequately assessed.

METHODS

Retrospective review of 203 patients, divided into 2 eras (era 1, 102 patients; era 2, 101 patients) of patients who underwent transsphenoidal surgery for acromegaly by a single surgeon over 11 years, was performed, determining the effect of surgical experience on rates of remission and various complications. Remission was defined according to the 2014 Endocrine Society Clinical Practice Guideline.

RESULTS

The rate of surgical remission was 40.6% (62.9% among noninvasive adenomas). Rates of surgical remission significantly improved in the latter half of this cohort (31.2% in the first half vs. 50% in the second half), despite other factors being comparable. On multivariate analysis, surgeon experience, cavernous sinus invasion, and preoperative growth hormone levels affected the rates of surgical remission. Rates of cerebrospinal fluid leak and hypopituitarism were lower in the second half, whereas resolution of acromegaly-associated comorbidities was increased.

CONCLUSIONS

We report, in this large single-surgeon review of endoscopically operated acromegaly cases, increased rates of surgical remission and reduced complications with increasing surgeon experience. The overall experience of the treating team in dealing with perioperative and intraoperative factors also contributes to improved outcomes.