Long-Term Endocrine Outcomes Following Endoscopic Endonasal Transsphenoidal Surgery for Acromegaly and Associated Prognostic Factors

A single-center prospective study evaluating the relationship of tumor consistency on remission in acromegaly patients

The nature of somatotroph adenomas has not been clearly revealed in studies. We consider that there are macroscopic differences in intraoperative tumor consistency in acromegaly patients. We aimed to determine whether there is a relationship between intraoperative tumor consistency and histopathological subtypes by planning a prospective study to determine whether these differences are significant. Between August 1997 and December 2021, 1118 patients with GH-secreting tumors underwent endoscopic endonasal surgery at our Pituitary Research Center. Between January 2022 and May 2023, pure GH-secreting adenomas operated via the endoscopic endonasal approach were sequentially categorized into three types(Type-1:Soft, Type-2:Mucinous/Adhesive, Type-3:Mix/Intermediate) according to the intraoperative tumor consistency. The final patient cohort consisted 218 cases. The ratio of densely granulated adenomas(DG-A) to sparsely granulated adenomas(SG-A) was as follows: Type-1, 89/11; Type-2, 5/95; Type-3, 13/5. Logistic regression revealed that Type-1 tumors were associated with a high remission rate(p = 0.011), and Type-2 were associated with SG-A(p < 0.001). Furthermore, no or weak staining for E-cadherin was associated with Type-2 tumors(p < 0.001). Surgeon could predict the prognosis and histopathological subtype of the pure somatotroph adenoma by observing the intraoperative tumor consistency. This could facilitate better intraoperative planning of patient-specific surgical strategies to increase the remission rates.

Targeting RACGAP1 suppresses growth hormone pituitary adenoma growth

PURPOSE

Growth hormone pituitary adenoma (GHPA) is a major subtype of pituitary adenoma (PA), with tumor enlargement and abnormal secretion of growth hormone (GH) often causing complications. Rac GTPase-activating protein 1 (RACGAP1), a member of the guanine triphosphatase-activating protein family, is highly overexpressed in multiple tumors and promotes tumor growth. However, the role of RACGAP1 in GHPA remains unelucidated. Besides, specific inhibitors targeting RACGAP1 have not yet been developed. In this study, we aimed to determine the expression and function of RACGAP1 in GHPA and identify effective inhibitors against RACGAP1.

METHODS

Immunohistochemistry was used to detect the expression of RACGAP1 in GHPA and normal pituitary tissues. The effect of RACGAP1 on cell proliferation, apoptosis, and cell cycle was evaluated by knockdown of RACGAP1 in GH3 cells in vitro and xenograft models of GHPA in vivo. The downstream mechanism of RACGAP1 was explored by RNA sequencing, bioinformatic analysis, and Western blot. Inhibitors targeting RACGAP1 were screened and verified through a structure-based virtual docking method, cell viability assays, and surface plasmon resonance (SPR) experiments.

RESULTS

RACGAP1 expression was increased in GHPA compared with normal pituitary tissues. Knocking down RACGAP1 suppressed cell growth in vitro and in vivo. Preliminary mechanism studies indicated that inhibition of RACGAP1 led to the upregulation of p21 and the downregulation of several genes involved in the cell cycle signaling pathway, such as Cyclin A, CDK1, and CDK2. Moreover, DB07268 was identified for the first time as an effective RACGAP1 inhibitor that could prominently restrain the proliferation of GH3 cells.

CONCLUSION

This study demonstrates that RACGAP1 plays a critical role in GHPA, highlighting the novel inhibitor DB07268 as a promising therapeutic approach.

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.

Integrative clinical, hormonal, and molecular data associate with invasiveness in acromegaly: REMAH study

INTRODUCTION

Growth hormone (GH)-secreting pituitary tumors (GHomas) are the most common acromegaly cause. At diagnosis, most of them are macroadenomas, and up to 56% display cavernous sinus invasion. Biomarker assessment associated with tumor growth and invasion is important to optimize their management.

OBJECTIVES

The study aims to identify clinical/hormonal/molecular biomarkers associated with tumor size and invasiveness in GHomas and to analyze the influence of pre-treatment with somatostatin analogs (SSAs) or dopamine agonists (DAs) in key molecular biomarker expression.

METHODS

Clinical/analytical/radiological variables were evaluated in 192 patients from the REMAH study (ambispective multicenter post-surgery study of the Spanish Society of Endocrinology and Nutrition). The expression of somatostatin/ghrelin/dopamine system components and key pituitary/proliferation markers was evaluated in GHomas after the first surgery. Univariate/multivariate regression studies were performed to identify association between variables.

RESULTS

Eighty percent of patients harbor macroadenomas (63.8% with extrasellar growth). Associations between larger and more invasive GHomas with younger age, visual abnormalities, higher IGF1 levels, extrasellar/suprasellar growth, and/or cavernous sinus invasion were found. Higher GH1 and lower PRL/POMC/CGA/AVPR1B/DRD2T/DRD2L expression levels (P < .05) were associated with tumor invasiveness. Least Absolute Shrinkage and Selection Operator's penalized regression identified combinations of clinical and molecular features with areas under the curve between 0.67 and 0.82. Pre-operative therapy with DA or SSAs did not alter the expression of any of the markers analyzed except for DRD1/AVPR1B (up-regulated with DA) and FSHB/CRHR1 (down-regulated with SSAs).

CONCLUSIONS

A specific combination of clinical/analytical/molecular variables was found to be associated with tumor invasiveness and growth capacity in GHomas. Pre-treatment with first-line drugs for acromegaly did not significantly modify the expression of the most relevant biomarkers in our association model. These findings provide valuable insights for risk stratification and personalized management of GHomas.

A single-center experience of transsphenoidal endoscopic surgery for acromegaly in 73 patients: results and predictive factors for remission

BACKGROUND

Transsphenoidal endoscopic surgery is the first-line treatment for growth hormone-secreting adenomas.

OBJECTIVE

To analyse the results of the transsphenoidal endoscopic approach for acromegaly and to determine the predictive factors of remission.

METHODS

A single-centre retrospective review was performed in patients who underwent endoscopic transsphenoidal surgery for acromegaly between January 2009 and January 2019. Demographic features, clinical presentation, histopathology records, complications and pre- and postoperative radiologic and endocrinological assessments were evaluated. The factors that influenced the remission rates were investigated.

RESULTS

A total of 73 patients underwent surgery via the transsphenoidal endoscopic approach. Cavernous sinus invasion was detected in 32 patients (43.8%); and macroadenoma, in 57 (78%). The pathology specimens of the 27 patients (36.9%) showed dual-staining adenomas with prolactin. A total of 51 patients (69.8%) attained biochemical remission 1 year after surgery. A second operation was performed in 10 patients (13.6%) with residual tumours without biochemical remission in the first year. Six (60%) of the patients attained remission at the last follow-up. Transient diabetes insipidus was observed in 18 patients (24.6%); and rhinorrhoea, which was resolved with conservative treatment, in 4 (5.4%). None of the patients developed panhypopituitarism. The presence of cavernous sinus invasion and preoperative IGF-1, immediate postoperative GH and third-month IGF-1 levels were predictive of remission.

CONCLUSION

Transsphenoidal endoscopic surgery is a safe and effective treatment for acromegaly. Reoperation should be considered in patients with residual tumours without remission.

Early Predictors of Remission in Acromegaly Patients after Pure Endoscopic Endonasal Transsphenoidal Surgery

Objective Surgery is the first-line treatment in acromegaly but it takes months to confirm remission. It is crucial to determine remission early in order to inform the patient and plan further treatment options. We aimed to evaluate the predictors of remission at the early phase after endoscopic endonasal pituitary surgery in acromegaly patients.

Methods Fifty-four growth hormone (GH)-adenoma patients operated via pure endoscopic endonasal approach were analyzed in this observational study. We compared the basic clinical, radiological characteristics, and the preoperative and postoperative hormone levels in terms of remission according to current guidelines.

Results The surgical remission rate was 61.1%. When the patients were compared according to surgical remission, the age, gender, and immunohistochemical granulation type were found to be nonsignificant, while diabetes mellitus was more common (55.6 vs. 44.4%). The preoperative tumor volume (1.2 ± 0.9 vs. 4.1 ± 4.2 cm3) and postoperative GH and insulin-like growth factor-1 (IGF-1) levels were higher in the nonremission group (p < 0.05). We defined a number of cut-off values of both GH and IGF-1 levels to predict remission at the postoperative phase. Age standardized regression analyses showed that postoperative day 1 (POD-1) GH levels (odds ratio [OR]: 8.9; 95% confidence interval [CI]: 1.99–40.0, p = 0.004) and tumor volume (OR: 3.14; 95% CI: 1.09–9.0, p = 0.034) were found to be significant independent predictors for remission.

Conclusion We demonstrated that tumor volume and POD-1 GH levels are independent predictors of remission in acromegaly patients operated via the pure endoscopic endonasal technique and may be used as an early marker of remission, and this may lead to taking adjuvant medical therapies early into account to improve prognosis.

Assessment of multimodal treatment options in recurrent and persistent acromegaly: a systematic review and meta-analysis

PURPOSE

In patients with acromegaly, secondary treatment options in cases of hormonal non-remission or tumor progression include repeat transsphenoidal surgery (TSS), radiation-based treatment (RT), or medical therapy (MT). In this study, we aim to evaluate the clinical effectiveness of various second-line treatment options for acromegaly.

METHODS

Using the PRISMA guideline, a systematic review was performed by searching MEDLINE (PubMed), Web of Science, Scopus, and Cochrane electronic bibliographic databases from conception to the end of 2022. Outcomes of interest included hormonal remission rate, complications, and mortality associated with each treatment modality for refractory acromegaly.

RESULTS

A total of 79 studies including 3,208 refractory acromegaly patients (44.90% males) were analyzed, with a mean patient age of 43.89 years. There was a statistically significant difference between various therapeutic modalities in terms of remission rate, with MT offering the highest remission rate (62.55%), followed by RT (50.15%) and TSS (37.39%). Subgroup analysis of radiotherapeutic and medical modalities did not show a significant difference in remission rate between different kinds of sub-modalities in each treatment approach. Recurrence following secondary treatment was not different in patients treated with reoperation TSS compared to other modalities.

CONCLUSIONS

The management of persistent and recurrent acromegaly optimally requires a multimodal approach. In different scenarios of refractory acromegaly based on previous treatment, secondary treatments may vary in terms of remission rate and complications. Medical agents provide considerable effectiveness as a second-line therapy for recurrent or persistent disease. In selected cases, however, reoperation still provides an opportunity for cure or freedom from medications. The findings of this study may help clinicians to prioritize varying options involved in this multifaceted decision-making process.

Pasireotide effects on biochemical control and glycometabolic profile in acromegaly patients switched from combination therapies or unconventional dosages of somatostatin analogs

PURPOSE

To evaluate the impact of pasireotide (PAS) therapy on hormonal and glycometabolic outcome in patients with acromegaly previously treated with combination medical therapies or unconventional dosages of first-generation somatostatin receptor ligands (fg-SRLs).

METHODS

Retrospective study carried out in two referral centers for pituitary diseases. Twenty-one acromegalic patients were switched to PAS (12 had biochemical control, 9 were uncontrolled). Data were collected after 3- and 6-months PAS treatment, and at the last available visit (median 35 months).

RESULTS

After switching to PAS therapy, a significant reduction in IGF-1 values was observed [median 39%; 0.79 xULN (IQR 0.5-1.01) vs 1.29 xULN (IQR 1.06-1.83); p = 0.009]. IGF-1 reduction was statistically significant in the 9 patients previously uncontrolled (61%, p = 0.016), and in the 12 controlled subjects (33%, p = 0.037). At last follow-up, the number of patients reaching an acceptable biochemical control (IGF-1 < 1.3 xULN) raised from 57 to 90% (p = 0.032). Mean HbA1c levels increased from 5.7% (5.5-5.9) to 6.0% (5.9-7) (p = 0.002), and the percentage of diabetic patients raised from 14% (3/21) to 67% (14/21) (p = 0.004). At the last evaluation HbA1c was ≥ 7.0% in 5 patients (24%). Antidiabetic drugs were initiated in 9 new patients, and in 7 out of 9 metformin alone was effective. Younger age and male sex were predictors for the maintenance of glucose homeostasis.

CONCLUSION

PAS monotherapy can be effective in acromegalic patients previously treated with combination medical therapies or unconventional dosages of fg-SRLs. Glucose imbalance can be managed in the vast majority of cases by use of lifestyle interventions and metformin.

Prospective Integrated Individualized Clinical Decision-making and Outcome Evaluation for Surgery in Patients with Acromegaly: A New Paradigm?

BACKGROUND

Growth-hormone-producing pituitary adenomas have variable likelihood for biochemical remission (BR). During preoperative counseling, individual estimated surgical likelihoods/risks should be balanced against alternative (medical) treatments, which is necessary for accurate outcome presentation. Preoperative estimation of BR or total resection (TR) likelihoods have not been reported, resulting in extrapolation of individual outcomes.

AIMS

To share an innovative outcome reporting paradigm by integrating surgical decision-making, and expected/realized results, resulting from the Value-Based Health Care (VBHC) care path with periodical performance evaluation and care innovation cycle.

METHODS

Prospective cohort study of consecutive patients with acromegaly undergoing surgery (January 2016-December 2020; postoperative follow-up ≥6 months) reporting on both classic, and novel innovative outcome evaluations.

RESULTS

Fifty eight patients (66 procedures) were included. Intended TR was achieved in 34/50 procedures, whereas intended debulking was achieved in 15/16 procedures. 38/66 procedures resulted in BR, and 4 procedures resulted in permanent complications. Achieving intended surgical goal was estimated preoperatively as likely in 33 (goal achieved (GA) in 28/33), potentially in 27 (GA in 19/27), and unlikely in 6 procedures (GA in 2/6). Integrated Outcome Square 1 (IOQ1) -intended effect achieved without complications- was achieved in 46/66 patients.

CONCLUSION

Implementation of the developed quality process positively affects preoperative individual shared decision-making, resulting in improved (individual) outcomes, particularly in complex patients for whom preoperative chances are not fully reflected by tumor size and KNOSP grade, e.g., reoperations, or other challenging circumstances identified during preoperative counseling. Through repeated evaluations, our own team's knowledge increased, allowing for improved individualized treatment strategies.

Pilot study to define criteria for Pituitary Tumors Centers of Excellence (PTCOE): results of an audit of leading international centers

PURPOSE

The Pituitary Society established the concept and mostly qualitative parameters for defining uniform criteria for Pituitary Tumor Centers of Excellence (PTCOEs) based on expert consensus. Aim of the study was to validate those previously proposed criteria through collection and evaluation of self-reported activity of several internationally-recognized tertiary pituitary centers, thereby transforming the qualitative 2017 definition into a validated quantitative one, which could serve as the basis for future objective PTCOE accreditation.

METHODS

An ad hoc prepared database was distributed to nine Pituitary Centers chosen by the Project Scientific Committee and comprising Centers of worldwide repute, which agreed to provide activity information derived from registries related to the years 2018-2020 and completing the database within 60 days. The database, provided by each center and composed of Excel® spreadsheets with requested specific information on leading and supporting teams, was reviewed by two blinded referees and all 9 candidate centers satisfied the overall PTCOE definition, according to referees' evaluations. To obtain objective numerical criteria, median values for each activity/parameter were considered as the preferred PTCOE definition target, whereas the low limit of the range was selected as the acceptable target for each respective parameter.

RESULTS

Three dedicated pituitary neurosurgeons are preferred, whereas one dedicated surgeon is acceptable. Moreover, 100 surgical procedures per center per year are preferred, while the results indicated that 50 surgeries per year are acceptable. Acute post-surgery complications, including mortality and readmission rates, should preferably be negligible or nonexistent, but acceptable criterion is a rate lower than 10% of patients with complications requiring readmission within 30 days after surgery. Four endocrinologists devoted to pituitary diseases are requested in a PTCOE and the total population of patients followed in a PTCOE should not be less than 850. It appears acceptable that at least one dedicated/expert in pituitary diseases is present in neuroradiology, pathology, and ophthalmology groups, whereas at least two expert radiation oncologists are needed.

CONCLUSION

This is, to our knowledge, the first study to survey and evaluate the activity of a relevant number of high-volume centers in the pituitary field. This effort, internally validated by ad hoc reviewers, allowed for transformation of previously formulated theoretical criteria for the definition of a PTCOE to precise numerical definitions based on real-life evidence. The application of a derived synopsis of criteria could be used by independent bodies for accreditation of pituitary centers as PTCOEs.

Pituitary adenomas registry in Thailand

PURPOSE

Pituitary adenomas are the most common sellar tumors, and may cause adverse outcomes in terms of morbidity and mortality if left untreated or if diagnosis is delayed. No data exists on the prevalence, characteristics, and prognosis of pituitary adenomas in Thailand. The systematic registration of clinical characteristics may improve patient care and prognosis for this disease in Thailand.

METHODS

This was a retrospective study conducted in 11 academic referral centers. All patients diagnosed with pituitary adenomas during the 2011---2014 period were enrolled in the study. The information was correlated with two national databases.

RESULTS

A total of 1,283 pituitary adenoma patients were identified. The adenomas were: non-functioning 50.1%, prolactinoma 29.4%, acromegaly 14.7%, Cushing disease 3.8%, gonadotropin-producing tumor 1.0%, TSH-secreting tumor 0.6%. The mean age was 49.2±15.2 years. Sixty-three percent of patients were female. Most common complaint was visual impairment (27.7%). The average size of the tumor was 22.2±16.1 mm. Fifty-nine percent of patients underwent surgery. Median follow-up was 27.4 months (0-24 years). After treatment, 72.4% improved, and 10.4% were cured. Overall results of treatment in non-functioning adenoma, prolactinoma (medically treated), acromegaly, Cushing, TSH, gonadotropin producing adenoma were: improved/cured in 81/5.5, 86/5.7, 55.9/30, 54.2/31.2, 85.7/14.3, 69.2/15.4% respectively.

CONCLUSION

Pituitary adenomas in academic centers in Thailand were found predominantly in female in the 4th decade of life. After treatment 72.4% of patients improved and 10% had full recovery. A health promotion system aimed to improve patient and physician recognition and physician expertise may improve the prognosis of these diseases.

Predictors of postoperative biochemical remission in lower Knosp grade growth hormone-secreting pituitary adenomas: a large single center study

PURPOSE

Growth hormone-secreting pituitary adenomas (GH-PAs) with a low Knosp grade are typically associated with a good postoperative biochemical remission (BR) rate. However, a proportion of patients do not achieve remission. In this study, we aimed to investigate predictive factors of postoperative remission for lower Knosp GH-PAs.

METHODS

In this retrospective study, we enrolled 140 patients who were diagnosed with lower Knosp (0-2) GH-PAs and received trans-sphenoidal surgery between December 2016 and June 2021 from the largest pituitary tumor surgery center in southern China. The univariate, binary Logistic regression, and receiver operating characteristic curve (ROC) analyses were employed to determine independent predictors and cutoff values of remission. The postoperative outcome was defined as remission using the 2010 consensus criteria of acromegaly.

RESULTS

One hundred and thirty six patients (97.1%) achieved gross total resection. The postoperative long-term BR was 68.6%. Empty sella, tumor maximum diameter and postoperative GH levels were independent factors predicting remission. ROC revealed that postoperative 24 h GH ≤ 1.3 ng/mL and  ≤ 1.23 ng/mL were valuable predictors for 3-month and long-term remission respectively, and that postoperative 3-month GH ≤ 1.6 ng/mL and tumor maximum diameter  ≤ 17 mm were predictors for delayed remission.

CONCLUSION

Early postoperative GH levels can be used as predictors of remission. However, BR was not associated with preoperative somatostatin analogs therapy or Knosp grade (0-2). For patients without residual tumor or recurrence and whose GH levels are slightly elevated within 1 year after surgery, adjuvant treatments may not be necessary.

Gigantism: microsurgical treatment by transsphenoidal approach and prognostic factors

PURPOSE

We present the results of transsphenoidal microsurgical treatment in 14 patients with gigantism. The influence on the prognosis of factors such as the tumor size and preoperative levels of GH and IGF-1 is also quantified.

MATERIALS AND METHODS

The patients, operated between 1982 and 2004, were reviewed retrospectively in June 2022. All patients had complete endocrinological studies in the preoperative period and a postoperative control between 6 days and 3 weeks. Follow-up has been supported with annual check-ups between 3 and 31 years. We have compared the preoperative levels of GH and IGF-1 of these patients with the levels of a series of acromegalic patients operated on in the same Center.

RESULTS

In this series there were 4 women and 10 men. The age ranged between 14 and 21 years. In 6 patients, postoperative hormone levels achieved the disease control criteria (42.8%). The CT/MRI studies revealed the existence of invasive tumors in 10 of the patients (71.4%). Postoperative CT/MRI showed no tumor tissue in 3 patients but in 7 patients there were tumor remains. The remaining 4 patients had abnormal images although not considered as tumor. A statistical comparison of preoperative serum GH and IGF-1 levels in patients with gigantism and patients with acromegaly showed a significant elevation in the former.

CONCLUSION

Pituitary adenomas that cause gigantism are generally large and invasive, which makes them difficult to cure. High preoperative levels of GH and IGF-1 are also factors that decrease remission.

Post-operative surveillance for somatotroph, lactotroph and non-functional pituitary adenomas after curative resection: a systematic review

CONTEXT

Pituitary tumors are the third most common brain tumor and yet there is no standardization of the surveillance schedule and assessment modalities after transsphenoidal surgery.

EVIDENCE ACQUISITION

OVID, EMBASE and the Cochrane Library databases were systematically screened from database inception to March 5, 2020. Inclusion and exclusion criteria were designed to capture studies examining detection of pituitary adenoma recurrence in patients 18 years of age and older following surgical resection with curative intent.

EVIDENCE SYNTHESIS

A total of 7936 abstracts were screened, with 812 articles reviewed in full text and 77 meeting inclusion criteria for data extraction. A pooled analysis demonstrated recurrence rates at 1 year, 5 years and 10 years for non-functioning pituitary adenomas (NFPA; N = 3533 participants) were 1%, 17%, and 33%, for prolactin-secreting adenomas (PSPA; N = 1295) were 6%, 21%, and 28%, and for growth-hormone pituitary adenomas (GHPA; N = 1257) were 3%, 8% and 13%, respectively. Rates of recurrence prior to 1 year were 0% for NFPA, 1-2% for PSPA and 0% for GHPA. The mean time to disease recurrence for NFPA, PSPA and GHPA were 4.25, 2.52 and 4.18 years, respectively.

CONCLUSIONS

This comprehensive review of the literature quantified the recurrence rates for commonly observed pituitary adenomas after transsphenoidal surgical resection with curative intent. Our findings suggest that surveillance within 1 year may be of low yield. Further clinical trials and cohort studies investigating cost-effectiveness of surveillance schedules and impact on quality of life of patients under surveillance will provide further insight to optimize follow-up.

Multidisciplinary management of difficult/aggressive growth-hormone pituitary neuro-endocrine tumors

Growth Hormone-secreting adenomas exhibits variable biological behavior and heterogeneous natural history, ranging from small adenomas and mild disease, to invasive and aggressive neoplasms with more severe clinical picture. Patients not cured or controlled after neurosurgical and first-generation somatostatin receptor ligands (SRL) therapy could require multiple surgical, medical and/or radiation treatments to achieve disease control. To date, no clinical, laboratory, histopathological, or neuroradiological markers are able to define the aggressiveness or predict the disease prognosis in patients with acromegaly. Therefore, the management of these patients requires careful evaluation of laboratory assessments, diagnostic criteria, neuroradiology examinations, and neurosurgical approaches to choose an effective and patient-tailored medical therapy. A multidisciplinary approach is particularly useful in difficult/aggressive acromegaly to schedule multimodal treatment, which includes radiation therapy, chemotherapy with temozolomide and other, recent emerging treatments. Herein, we describe the role of the different members of the multidisciplinary team according to our personal experience; a flow-chart for the therapeutic approach of difficult/aggressive acromegaly patients is proposed.

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.

The Prognostic-Based Approach in Growth Hormone-Secreting Pituitary Neuroendocrine Tumors (PitNET): Tertiary Reference Center, Single Senior Surgeon, and Long-Term Follow-Up

Postoperative deserved outcomes in acromegalic patients are to normalize serum insulin-like growth factor (IGF-1), reduce the tumoral mass effect, improve systemic comorbidities, and reverse metabolic alterations. Pituitary neuroendocrine tumors (PitNET) are characterized to present a heterogeneous behavior, and growth hormone (GH)-secreting PitNET is not an exception. Promptly determining which patients are affected by more aggressive tumors is essential to guide the optimal postoperative decision-making process [prognostic-based approach]. From 2006 to 2019, 394 patients affected by PitNET were intervened via endoscopic endonasal transsphenoidal approach by the same senior surgeon. A total of 44 patients that met the criteria to be diagnosed as acromegalic and were followed up at least for 24 months (median of 66 months (26-156) were included in the present study. Multiple predictive variables [age, gender, preoperative GH and IGF-1 levels, maximal tumor diameter, Hardy's and Knosp's grade, MRI. T2-weighted tumor intensity, cytokeratin expression pattern, and clinicopathological classification] were evaluated through uni- and multivariate statistical analysis. Sparse probability of long-term remission was related to younger age, higher preoperative GH and- or IGF-1, group 2b of the clinicopathological classification, and sparsely granulated cytokeratin expression pattern. Augmented recurrence risk was related to elevated preoperative GH levels, tumor MRI T2-weighted hyperintensity, and sparsely granulated cytokeratin expression pattern. Finally, elevated risk for reintervention was related to group 2b of the clinicopathological classification, Knosp's grade IV, and tumor MRI T2-weighted hyperintensity. In this study, the authors determined younger age, higher preoperative GH and- or IGF-1 levels, group 2b of the clinicopathological classification, Knosp's grade IV, MRI T2-weighted tumor hyperintensity and sparsely granulated cytokeratin expression pattern are related to worse postoperative outcomes in long-term follow-up patients affected with GH-secreting PitNET.

Molecular targets in acromegaly

Molecular therapeutic targets in growth hormone (GH)-secreting adenomas range from well-characterized surface receptors that recognize approved drugs, to surface and intracellular markers that are potential candidates for new drug development. Currently available medical therapies for patients with acromegaly bind to somatostatin receptors, GH receptor, or dopamine receptors, and lead to attainment of disease control in most patients. The degree of control is variable: however, correlates with both disease aggressiveness and tumor factors that predict treatment response including somatostatin receptor subtype expression, granulation pattern, kinases and their receptors, and other markers of proliferation. A better understanding of the mechanisms underlying these molecular markers and their relationship to outcomes holds promise for expanding treatment options as well as a more personalized approach to treating patients with acromegaly.

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.

Surgery as a first-line option for prolactinomas

INTRODUCTION

Treatment of prolactinomas with dopamine agonists has been the established first-line treatment option for many years, with surgery reserved for refractory cases or medication intolerance. This approach may not be the best option in many cases.

AREAS COVERED

Review of the epidemiology, biology, and treatment options available for prolactinomas, including best available data on outcomes, costs, and morbidities for each therapy. These data are then used to propose a 'surgery-first' treatment approach for a subset of prolactinomas as an alternative to primary medical management.

EXPERT OPINION

Based on the available data, there is a strong rationale that transsphenoidal surgery should be considered a first-line treatment option for both micro- and macro-prolactinomas that do not demonstrate high grade cavernous sinus invasion on MRI imaging, with dopamine agonists administered as a secondary therapy for tumors not in remission following surgery, and for giant tumors. This 'surgery-first' approach assumes the availability of skilled and experienced pituitary surgeons to ensure optimal outcomes. This approach should result in high cure rates and reduced DA requirements for patients not cured from initial surgery. Further, it will reduce medical costs over a patient's lifetime and the chronic morbidities associated with protracted dopamine agonist usage.

Acromegaly: pathogenesis, diagnosis, and management

Growth hormone-secreting pituitary adenomas that cause acromegaly arise as monoclonal expansions of differentiated somatotroph cells and are usually sporadic. They are almost invariably benign, yet they can be locally invasive and show progressive growth despite treatment. Persistent excess of both growth hormone and its target hormone insulin-like growth factor 1 (IGF-1) results in a wide array of cardiovascular, respiratory, metabolic, musculoskeletal, neurological, and neoplastic comorbidities that might not be reversible with disease control. Normalisation of IGF-1 and growth hormone are the primary therapeutic aims; additional treatment goals include tumour shrinkage, relieving symptoms, managing complications, reducing excess morbidity, and improving quality of life. A multimodal approach with surgery, medical therapy, and (more rarely) radiation therapy is required to achieve these goals. In this Review, we examine the epidemiology, pathogenesis, diagnosis, complications, and treatment of acromegaly, with an emphasis on the importance of tailoring management strategies to each patient to optimise outcomes.

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.

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.

Association of pre- and postoperative αKlotho levels with long-term remission after pituitary surgery for acromegaly

Soluble αKlotho (sKl) is a disease-specific biomarker that is elevated in patients with acromegaly and declines after surgery for pituitary adenoma. Approximately 25% of patients do not achieve remission after surgery, therefore a risk stratification for patients early in the course of their disease may allow for the identification of patients requiring adjuvant treatment. Growth hormone (GH) and insulin-like growth factor-1 (IGF-1) have been assessed as biomarker for disease activity, however the value of sKl as a predictive biomarker of surgical success has not been evaluated yet. In this study, we measured serum biomarkers before and after transsphenoidal pituitary surgery in 55 treatment-naïve patients. Based on biochemical findings at follow-up (7–16 years), we divided patients into three groups: (A) long-term cure (defined by normal IGF-1 and random low GH (< 1 μg/l) or a suppressed GH nadir (< 0.4/μg/l) on oral glucose testing); (B) initial remission with later disease activity; (C) persistent clinical and/or biochemical disease activity. sKl levels positively related to GH, IGF-1 levels and tumor volume. Interestingly, there was a statistically significant difference in pre- and postoperative levels of sKl between the long-term cure group and the group with persistent disease activity. This study provides first evidence that sKl may serve as an additional marker for surgical success, decreasing substantially in all patients with initial clinical remission while remaining high after surgery in patients with persistent disease activity.

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.

Approach to the Patient With Treatment-resistant Acromegaly

Although most tumors in patients with acromegaly are benign and are cured or controlled by surgery and/or first-generation somatostatin receptor ligands therapy, some can behave more aggressively and are resistant to these standard therapies. Acromegaly, if left untreated, is a rare and chronic disorder, commonly caused by a GH-producing pituitary adenoma and is associated with significant comorbidities and an increased mortality. Transsphenoidal surgery is considered the mainstay of acromegaly management, but medical therapy has an increasingly important role. However, disease activity is not fully controlled in a significant number of patients treated with surgery and/or high-dose first-generation somatostatin receptor ligand monotherapy. In these circumstances, therefore, repeated surgery, second-line medical therapy, and radiotherapy, alone or combined as multimodal therapeutic strategies should be considered, in a patient-centered perspective.

The p300 Inhibitor A-485 Exerts Antitumor Activity in Growth Hormone Pituitary Adenoma

CONTEXT

Growth hormone pituitary adenoma (GHPA), a major subtype of pituitary adenoma (PA), can lead to progressive somatic disfigurement, multiple complications, and even increased mortality. The efficacy of current treatments is limited; thus, a novel pharmacological treatment is urgently needed. As a histone acetyltransferase (HAT) coactivator, p300 can regulate the transcription of several genes that are crucial for PA tumorigenesis and progression. However, the role of p300 and its catalytic inhibitor in GHPA is still unclear.

OBJECTIVE

We aimed to identify the expression of p300 in GHPA and in normal pituitary glands.

METHODS

The expression of p300 was detected in GHPA and normal pituitary tissues. Genetic knockdown was performed by siRNA. The efficacy of the p300 inhibitor A-485 in the cell cycle, proliferation, apoptosis, and hormone secretion was investigated by flow cytometry, ELISAs, Western blotting, and qRT-PCR. RNA sequencing, bioinformatic analysis, and subsequent validation experiments were performed to reveal the potential biological mechanism of A-485.

RESULTS

High expression of p300 was found in GHPA tissues compared with normal pituitary tissues. Knockdown of p300 inhibited cell proliferation and clone formation. Treatment with A-485 suppressed cell growth and inhibited the secretion of GH in vitro and in vivo. Further mechanistic studies showed that A-485 could downregulate the expression or activity of several oncogenes, such as genes in the Pttg1, c-Myc, cAMP and PI3K/AKT/mTOR signaling pathways, which are crucial for PA tumorigenesis and progression.

CONCLUSION

Our findings demonstrate that inhibition of HAT p300 by its selective inhibitor A-485 is a promising therapy for GHPA.

Diagnosis and Treatment of Acromegaly: An Update

Acromegaly is typically caused by a growth hormone-secreting pituitary adenoma, driving excess secretion of insulin-like growth factor 1. Acromegaly may result in a variety of cardiovascular, respiratory, endocrine, metabolic, musculoskeletal, and neoplastic comorbidities. Early diagnosis and adequate treatment are essential to mitigate excess mortality associated with acromegaly. PubMed searches were conducted using the keywords growth hormone, acromegaly, pituitary adenoma, diagnosis, treatment, pituitary surgery, medical therapy, and radiation therapy (between 1981 and 2021). The diagnosis of acromegaly is confirmed on biochemical grounds, including elevated serum insulin-like growth factor 1 and lack of growth hormone suppression after glucose administration. Pituitary magnetic resonance imaging is advised in patients with acromegaly to identify an underlying pituitary adenoma. Transsphenoidal pituitary surgery is generally first-line therapy for patients with acromegaly. However, patients with larger and invasive tumors (macroadenomas) are often not in remission postoperatively. Medical therapies, including somatostatin receptor ligands, cabergoline, and pegvisomant, can be recommended to patients with persistent disease after surgery. Select patients may also be candidates for preoperative medical therapy. In addition, primary medical therapy has a role for patients without mass effect on the optic chiasm who are unlikely to be cured by surgery. Clinical, endocrine, imaging, histologic, and molecular markers may help predict the response to medical therapy; however, confirmation in prospective studies is needed. Radiation therapy is usually a third-line option and is increasingly administered by a variety of stereotactic techniques. An improved understanding of the pathogenesis of acromegaly may ultimately lead to the design of novel, efficacious therapies for this serious condition.

Endocrine response and outcome in 14 cats with insulin resistance and acromegaly treated with stereotactic radiosurgery (17 Gy)

OBJECTIVE

To describe clinical outcomes in cats with insulin resistance and acromegaly treated with stereotactic radiosurgery (SRS).

ANIMALS

14 client-owned cats.

PROCEDURES

Medical records of cats with insulin resistance and acromegaly treated with SRS (17 Gy) between August 2013 and November 2019 at a single institution were reviewed. Kaplan-Meier analysis was used to evaluate overall survival time.

RESULTS

Acute adverse effects of SRS included somnolence (n = 2) and alopecia (1). Delayed adverse effects of SRS included unspecified neurologic complications (n = 1; 481 days), seizures (1; 1,541 days), and hypothyroidism (1; 64 days). Exogenous insulin requirements decreased in 10 of the 14 cats, with a median time to lowest insulin dose of 399 days (range, 42 to 879 days). Complete diabetic remission was achieved in 3 cats. The median overall survival time was 741 days (95% CI, 353 to 1,129 days). Six cats were still alive at the end of the study period, with a median follow-up time of 725 days. In 7 of the 8 cats that had died, death was presumptively attributed to acromegaly owing to continued insulin resistance, organ failure, or altered neurologic status.

CLINICAL RELEVANCE

The SRS protocol was well tolerated and associated with survival times similar to those reported previously. Most cats had decreased exogenous insulin requirements after SRS. Latency to an endocrine response was highly variable, emphasizing the need for careful ongoing diabetic monitoring of acromegalic cats after pituitary gland irradiation.

Clinical, hormonal and pathomorphological markers of somatotroph pituitary neuroendocrine tumors predicting the treatment outcome in acromegaly

BACKGROUND

Transsphenoidal adenomectomy (TSS) of somatotroph pituitary neuroendocrine tumor (PitNET) is the first-line treatment of acromegaly. Pharmacological treatment is recommended if surgery is contraindicated or did not lead to disease remission. The choice of treatment best fitting each patient should be based on thorough investigation of patients' characteristics. The current analysis attempts to create a tool for personalized treatment planning.

AIM

This study aimed to assess whether clinical, biochemical, imaging and pathological characteristics can predict surgical remission and response to first-generation somatostatin receptor ligands (SRLs) and pasireotide-LAR in acromegaly.

PATIENTS AND METHODS

A retrospective study of 153 acromegaly patients, treated in the Department of Endocrinology in Bielanski Hospital in Warsaw, Poland was performed. Data on demographics, hormonal and imaging results, pathological evaluation, and treatment outcome was extracted from the Polish Acromegaly Registry collecting information from 11 endocrinology centers in Poland and analyzed.

RESULTS

Patients with surgical remission had lower GH and IGF-1 concentrations at diagnosis (median GH 5.5 µg/L [IQR: 3.1-16.0] vs. 19.9 µg/L [IQR: 9.8-42.4], p=<0.001 and mean IGF-1 3.1xULN ± SD=1.2 vs. 3.7xULN ± SD=1.2, p=0.007, respectively) and smaller tumors (median 12.5mm [IQR: 9-19] vs. 23mm [IQR: 18-30], p<0.001). These tumors were more often densely granulated (DG) (73.2% vs. 40.0%, p=0.001) with positive staining for alpha-subunit (α-SU) (58.3% vs. 35.5%, p=0.021) and lower Ki-67 index (p=0.002). Patients responding well to SRLs were more often male (55.6% vs 44.4%, p=0.026), presented lower GH concentration (median GH 17.2 µg/L [IQR: 6.2-29.0] vs. 23.8 µg/L [IQR: 11.2-49.5], p=0.048) and had more often DG tumors (63.0% vs. 14.3%, p<0.001). No significant differences between good and poor-response to pasireotide-LAR groups were found. In multivariate logistic regression analysis fasting GH concentration <8.63 µg/L, maximal tumor diameter <15.5mm, normoprolactinemia and DG tumor turned out to be independent predictors of surgical remission (OR=0.92, p=0.026; OR=0.87, p=0.069, OR=3.86, p=0.096 and OR=3.05, p=0.181, respectively). Fasting GH concentration <36.6 µg/L and DG tumor turned out to be independent predictors of good response to first-generation SRLs (OR=0.96, p=0.06 and OR=10.68, p=0.002, respectively).

CONCLUSIONS

Younger age at diagnosis, male sex, lower GH, IGF-1 and PRL concentrations, smaller tumor size at diagnosis as well as positive α-SU staining, lower Ki-67 index and DG tumors predicted better treatment outcome in acromegaly patients.

Novel Classification of Acromegaly in Accordance with Immunohistochemical Subtypes: Is There Really a Clinical Relevance?

According to the recent studies, immunohistochemical subtypes of growth hormone (GH) secreting adenomas have been considered as a predictive factor in determining the clinical outcomes including biochemical, radiologic, and endocrine remission. In a 20 year-of time period, acromegaly patients who were treated and followed at the Endocrinology Department of our University Hospital were screened for the study. Of total 98 patients, 65 patients who had been operated by transsphenoidal surgery and having postoperative specimens were included. Postoperative specimens of the surgery of the patients were classified into 3 groups based on the histochemical characteristics (densely, sparsely, and mixed). Parasellar extensions of pituitary tumors were classified into the five grades according to Knosp classification. The patients were investigated and evaluated for postoperative clinical progress, remission rates, comorbidities regarding with the histopathological patterns. Of total 65 patients, 31 were classified as densely granulated (group 1), 32 were classified as sparsely granulated (group 2), and 2 patients were assessed as mixed granulated (group 3). There was no difference between groups for age and gender. Pre-treatment of adenoma size in all groups was correlated with each other and the frequency of macroadenoma (1 vs. 2, 77.4 vs. 84.3%) was higher in two groups. Although mean initial GH levels in group 1 was higher than the other groups (p=0.03), IGF1 levels (age and gender matched) were similar in each group. Adenomas in all groups demonstrated noninvasive radiological characteristics (Knosp grade 0-1-2). Ki-67 proliferation index of both groups (64.5 vs. 50%) was predominantly 1%. With a similar follow-up period, the endocrine remission rates (GH<1 μg/l) in groups were 64 vs. 69%, respectively. In conclusion, classification according to immunohistochemical subtypes of growth hormone secreting adenomas may not be a qualified parameter to evaluate patients with patterns of aggressiveness, clinical outcomes, or treatment response.

Early postoperative prediction of both disease remission and long-term disease control in acromegaly using the oral glucose tolerance test

PURPOSE

Transsphenoidal surgery (TSS) is the cornerstone of acromegaly treatment. Two biochemical parameters, growth hormone (GH) and insulin-like growth factor-1 (IGF-1) levels, sometimes diverge postoperatively; however, it is important to maintain disease control without further treatment, regardless of whether these parameters converge. This study investigated whether remission and long-term disease control could be predicted using early postoperative GH and IGF-1 levels.

METHODS

We reviewed 36 consecutive surgically treated patients with acromegaly. IGF-1 levels and minimum GH levels during an oral glucose tolerance test (OGTT) were evaluated at 2 weeks, as well as at 3 months postoperatively. After comparison between the remission and nonremission groups, we analyzed whether early postoperative parameters could predict remission and long-term disease control.

RESULTS

Twenty-five patients (69.4%, Group A) achieved remission within 1 year postoperatively. Of the remaining patients (median follow-up period, 53 months), seven (19.5%, Group B) maintained normal IGF-1 levels without treatment, whereas four (11.1%, Group C) required additional treatment. GH levels <1.5 ng/mL measured on the morning after surgery and nadir GH levels <0.7 ng/mL during the OGTT conducted at 2 weeks postoperatively were predictive of remission, with the latter demonstrating 95.2% sensitivity and 100% specificity. All group C patients had nadir GH levels ≥0.7 ng/mL during the OGTT and IGF-1 levels ≥SD +3 at 2 weeks postoperatively.

CONCLUSION

Early postoperative nadir GH levels during the OGTT and IGF-1 levels at 2 weeks postoperatively demonstrated excellent predictive value for both endocrinological remission and the necessity for additional treatment.

Neural network modeling for prediction of recurrence, progression, and hormonal non-remission in patients following resection of functional pituitary adenomas

PURPOSE

Functional pituitary adenomas (FPAs) cause severe neuro-endocrinopathies including Cushing's disease (CD) and acromegaly. While many are effectively cured following FPA resection, some encounter disease recurrence/progression or hormonal non-remission requiring adjuvant treatment. Identification of risk factors for suboptimal postoperative outcomes may guide initiation of adjuvant multimodal therapies.

METHODS

Patients undergoing endonasal transsphenoidal resection for CD, acromegaly, and mammosomatotroph adenomas between 1992 and 2019 were identified. Good outcomes were defined as hormonal remission without imaging/biochemical evidence of disease recurrence/progression, while suboptimal outcomes were defined as hormonal non-remission or MRI evidence of recurrence/progression despite adjuvant treatment. Multivariate regression modeling and multilayered neural networks (NN) were implemented. The training sets randomly sampled 60% of all FPA patients, and validation/testing sets were 20% samples each.

RESULTS

348 patients with mean age of 41.7 years were identified. Eighty-one patients (23.3%) reported suboptimal outcomes. Variables predictive of suboptimal outcomes included: Requirement for additional surgery in patients who previously had surgery and continue to have functionally active tumor (p = 0.0069; OR = 1.51, 95%CI 1.12-2.04), Preoperative visual deficit not improved after surgery (p = 0.0033; OR = 1.12, 95%CI 1.04-1.20), Transient diabetes insipidus (p = 0.013; OR = 1.27, 95%CI 1.05-1.52), Higher MIB-1/Ki-67 labeling index (p = 0.038; OR = 1.08, 95%CI 1.01-1.15), and preoperative low cortisol axis (p = 0.040; OR = 2.72, 95%CI 1.06-7.01). The NN had overall accuracy of 87.1%, sensitivity of 89.5%, specificity of 76.9%, positive predictive value of 94.4%, and negative predictive value of 62.5%. NNs for all FPAs were more robust than for CD or acromegaly/mammosomatotroph alone.

CONCLUSION

We demonstrate capability of predicting suboptimal postoperative outcomes with high accuracy. NNs may aid in stratifying patients for risk of suboptimal outcomes, thereby guiding implementation of adjuvant treatment in high-risk patients.

Preoperative prediction of granulation pattern subtypes in GH-secreting pituitary adenomas

OBJECTIVE

The aim of this study was to establish a preoperative prediction method for sparsely granulated (SG) growth hormone (GH)-secreting pituitary adenoma, an aggressive tumour subtype with high recurrence risk, in acromegaly patients.

METHODS

Eighty-three patients with GH-secreting pituitary adenomas were included in this study. GH measurements, cytokeratin immunostaining and electron microscopy were performed to detect granulation patterns. Preoperative factors, including general, radiological and endocrinological features and acute octreotide suppression test outcomes, were compared between SG and densely granulated (DG) groups. The predictive capabilities of these features were analysed using a receiver operating characteristic (ROC) curve, and the most predictive features were combined to establish a grading scale.

RESULTS

Thirty-nine of the 83 patients had SG GH-secreting pituitary adenomas; 44 had DG tumours. SG tumours tended to occur in younger patients and have larger diameters and volumes, higher Knosp grades, lower GH indexes and normalized insulin-like growth factor-1 (IGF-1) level, and a lower ∆GH% after octreotide treatment. The tumour size, Knosp grade, GH index and ∆GH% after octreotide treatment had good predictive performance, with area under the curve (AUC) values ranging from 0.70 to 0.80. Combining four parameters, including diameter, Knosp grade, GH index and ∆GH% after octreotide treatment, we established a grading scale for predicting SG GH-secreting pituitary adenomas with an AUC of 0.84 and relatively high sensitivity and specificity.

CONCLUSIONS

We propose a predictive method for distinguishing SG and DG GH-secreting pituitary adenomas preoperatively. This method will help physicians identify candidates for presurgical medical treatment and neurosurgeons determine radical surgical strategies for high-risk tumours.

Comparative effectiveness of endoscopic versus microscopic transsphenoidal surgery for patients with growth hormone secreting pituitary adenoma: An emulated trial

INTRODUCTION

Previous studies failed to show the benefit of endoscopic surgery over microscopic surgery in terms of early endocrine remission. This study was to investigate whether early endocrine outcomes in patients with GH-secreting pituitary adenoma underwent endoscopic transsphenoidal surgery would be better than those operated by microscopic surgery.

METHODS

An acromegaly database collected from 2010 to 2019 in a single institution was used to emulate a randomized trial. Adult patients operated by a transsphenoidal approach using either endoscope or microscope were included. The primary outcome was endocrine remission based on insulin-like growth factor-1 (IGF-1) at six-month follow-up after surgery. We used inverse probability weighting to construct a pseudo population from which the treatment effect was estimated.

RESULTS

In the original cohort, 1118 patients underwent transsphenoidal surgery (424 with an endoscopic approach and 694 with a microscopic approach). Patients treated with endoscopic surgery were more likely to be previously surgical treated and to have an invasive tumor than patients who underwent microscopic surgery. In the pseudo population, the proportion of endocrine remission was 54.9% in the endoscopic group and 42.0% in the microscopic group (odds ratio, 1.68; 95% CI, 1.27-2.23). This finding was consistent and robust across several sensitivity analyses.

CONCLUSIONS

Among patients with growth hormone secreting pituitary adenoma who underwent transsphenoidal surgery, endoscopic surgery was associated with higher early endocrine remission than microscopic surgery.

Revisiting the Role of Insulin-like Growth Factor-1 Measurement After Surgical Treatment of Acromegaly

CONTEXT

In the management of growth hormone (GH)-secreting pituitary adenomas, the oral glucose tolerance test (OGTT) has been the gold standard not only for diagnoses but also for the determination of biochemical remission. Insulin-like growth factor-1 (IGF-1) is an essential biomarker, although it should be adjusted for both age and sex.

OBJECTIVE

We evaluated whether IGF-1 levels could serve as a reliable alternative to an OGTT for disease monitoring after the surgical treatment of acromegaly. We retrospectively reviewed the medical records of 320 patients who underwent surgical resection of their GH-secreting pituitary tumors at the Severance hospital. Receiver operator characteristic (ROC) analyses were performed to validate the accuracy of IGF-1 levels for the assessment of remission. In addition, regression analyses were performed to identify factors associated with discrepancy between OGTT and IGF-1 levels.

RESULTS

Except for 1 week after surgery, ROC analyses showed an area under the curve of greater than 0.8 for IGF-1 at all time points. Of 320 patients, 270 achieved endocrine remission after surgery alone. Among these patients, IGF-1 levels were normalized in 250 patients. The mean duration from surgery to IGF-1 normalization was 4.7 months. Regression analyses demonstrated that risk of failed IGF-1 normalization was increased by 3.1-fold when the tumor invaded the cavernous sinus and increased by 9.0-fold in patients with incomplete tumor removal.

CONCLUSION

IGF-1 level is a reliable alternative to OGTT and plays a valuable role in monitoring acromegaly status.

Predictors for Remission after Transsphenoidal Surgery in Acromegaly: A Dutch Multicenter Study

CONTEXT

Transsphenoidal surgery (TSS) is the primary treatment of choice in acromegaly. It is important to identify patients in whom surgical cure is not attainable at an early stage, both to inform patients on expected treatment outcome and to select those who are more likely to need additional therapy.

OBJECTIVE

To identify predictors for remission after TSS in acromegaly.

METHODS

Large multicenter study with retrospective data collection from 3 tertiary neurosurgical referral centers in The Netherlands. We analyzed clinical data since 2000 from 3 cohorts (Groningen, Nijmegen, and Rotterdam, total n = 282). Multivariate regression models were used to identify predictors of early biochemical remission (12 weeks to 1 year postoperatively) according to the 2010 consensus criteria, long-term remission (age- and sex-normalized insulin-like growth factor 1 [IGF-1] and the absence of postoperative treatment until last follow-up), and relative IGF-1 and growth hormone [GH] reduction.

RESULTS

A larger maximum tumor diameter (odds ratio [OR] 0.91, 95% CI 0.87-0.96, P ≤ .0001) was associated with a lower chance of early biochemical remission. A larger maximum tumor diameter (OR 0.93, 95% CI 0.89-0.97, P = .0022) and a higher random GH concentration at diagnosis (OR 0.98, 95% CI 0.96-0.99, P = .0053) were associated with a lower chance of long-term remission.

CONCLUSION

Maximum tumor diameter and random GH concentration at diagnosis are the best predictors for remission after TSS in 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.

Clinical, biological, radiological, and pathological comparison of sparsely and densely granulated somatotroph adenomas: a single center experience from a cohort of 131 patients with acromegaly

PURPOSE

Growth hormone-producing pituitary adenomas are divided into two clinically relevant histologic subtypes, densely (DG-A) and sparsely (SG-A) granulated. Histologic subtype was evaluated in a large cohort of patients with acromegaly, separating DG-A and SG-A, and correlated with clinicopathological characteristics.

METHODS

Patients with acromegaly undergoing surgery as initial therapy between 1995 and 2015 were identified. Histologic subtype was determined by keratin expression pattern with CAM5.2 and correlated with clinical and imaging parameters, somatostatin receptor subtype 2 (SST2) expression, post-surgical remission rate, and application of a prognostic scoring system incorporating proliferation and invasiveness.

RESULTS

One hundred thirty-one patients were included. Tumors were classified as DG-A (75, 57.3%), SG-A (29, 22.1%), intermediate (I-A) (9, 6.9%), and unclassified (18, 13.7%) when CAM5.2 was negative. DG-A and I-A were combined for analysis (DG/I-A) and compared to SG-A. Age, gender, proliferation, and post-surgical remission did not differ. SG-A were larger [2 vs. 1.5 cm (median), p = 0.03], more frequently invasive [65.5% vs. 32.9%, p = 0.004], associated with higher MRI T2-weighted signal ratio [1.01 vs. 0.82 (median), p = 0.01], showed lower SST2 expression (p < 0.0001), and scored higher in the prognostic classification (p = 0.004). Surgical remission occurred in 41.7% DG/I-A and 41.4% SG-A (p = 1.0). On multivariate analysis, absence of invasion (p = 0.009) and lower pre-operative IGF-1 index (p = 0.0002) were associated with post-surgical remission.

CONCLUSION

CAM5.2 allowed distinction between DG/I-A and SG-A in most but not all cases. Histologic subtype did not predict surgical outcome. Absence of invasion and lower pre-operative IGF-1 index were the only significant predictors of post-surgical remission in this cohort.

Machine learning in predicting early remission in patients after surgical treatment of acromegaly: a multicenter study

PURPOSE

Accurate prediction of postoperative remission is beneficial for effective patient-physician communication in acromegalic patients. This study aims to train and validate machine learning prediction models for early endocrine remission of acromegalic patients.

METHODS

The training cohort included 833 patients with growth hormone (GH) secreting pituitary adenoma from 2010 to 2018. We trained a partial model (only using pre-operative variables) and a full model (using all variables) to predict off-medication endocrine remission at six-month follow-up after surgery using multiple algorithms. The models were validated in 99 prospectively collected patients from a second campus and 52 patients from a third institution.

RESULTS

C-statistic and the accuracy of the best partial model was 0.803 (95% CI 0.757-0.849) and 72.5% (95% CI 67.6-77.5%), respectively. C-statistic and the accuracy of the best full model was 0.888 (95% CI 0.861-0.914) and 80.3% (95% CI 77.5-83.1%), respectively. The c-statistics (and accuracy) of using only Knosp grade, total resection, or postoperative day 1 GH level as the single predictor were lower than our partial model or full model (p < 0.001). C-statistics remained similar in the prospective cohort (partial model 0.798, and full model 0.903) and in the external cohort (partial model 0.771, and full model 0.871). A web-based application integrated with the trained models was published at  https://deepvep.shinyapps.io/Acropred/ .

CONCLUSION

We developed and validated interpretable and applicable machine learning models to predict early endocrine remission after surgical resection of a GH-secreting pituitary adenoma. Predication accuracy of the trained models were better than those using single variables.

The impact of endoscopic transsphenoidal pituitary adenoma surgery on endocrine function: a single-centre study

INTRODUCTION

The outcome for pituitary endocrine function following endoscopic transsphenoidal surgery remains unclear. This study aims to evaluate endocrine outcomes following endoscopic surgery in order to provide a benchmark to assist in the counselling of patients perioperatively.

METHODS

A prospectively held pituitary database was retrospectively analysed for all adult pituitary adenoma patients undergoing endoscopic surgery from May 2011 to May 2017. All operations were performed by a single neurosurgeon at a regional centre for pituitary surgery. Functioning and non-functioning adenomas were included. Hormonal status was assessed at most recent follow-up.

RESULTS

One hundred forty-five patients (69 M, 76 F) were included in the study with a median age of 52 years. Median follow-up was 52 months. Eighty-eight patients (61%) were not taking any hormone replacement medications, whilst 57 patients (39%) required hormone replacement therapy (HRT) preoperatively. Preoperatively, 29 patients (20%) had hypothalamo-pituitary-adrenal (HPA) axis dysfunction, 39 patients (27%) had thyroid axis dysfunction, 11 males (16%) and 7 females (9%) had gonadal axis dysfunction, and one patient had preoperative diabetes insipidus. Postoperatively, 26 patients (18%) had a new deficiency in pituitary function, whilst 6 patients (11%) were able to cease HRT. Nineteen patients (13%) had new HPA axis deterioration, 12 (8%) had new thyroid axis dysfunction, 8 males (11%) and 4 females (5%) had gonadal axis deterioration, and 6 patients (4%) had new diabetes insipidus (DI).

CONCLUSIONS

The ability to restore pituitary function following endoscopic surgery remains limited, whilst new deficits still occur. It is essential that patients are counselled accordingly as hormonal replacement therapy can have a significant impact on quality of life. Larger longer-term collaborative studies of endocrine outcome in endoscopic pituitary surgery are needed.

[Early postoperative measurement of growth hormone level for prognosis of surgical outcomes in acromegaly]

AIM

To investigate the value of 24 hours post-surgery measurement of growth hormone (GH) level for prognosis of surgical outcomes in acromegaly.

MATERIALS AND METHODS

A prospective cohort study included 45 patients with newly diagnosed acromegaly. The degree of parasellar extension was measured on the preoperative sellar magnetic resonance imaging according to the Knosps classification. All patients underwent a transsphenoid adenomectomy performed by one neurosurgeon. Basal GH level was measured at 24 hours after surgery. The efficacy of transsphenoidal adenomectomy evaluated at 12 months after surgery.

RESULTS

Acromegaly remission was achieved in 19 (42%) of 45 patients at 12 months after surgery. Pituitary microadenomas and the absence of paracellular invasion, corresponding to Knosp Grade 02, had low prognostic value for long-term remission due to low sensitivity (31.6%) and low specificity (38.5%), respectively. The highest prognostic value for acromegaly remission was showed for 24 hours post-surgery GH level with cut-off 1.30 ng/ml with sensitivity of 96.2% (95% confidence interval 81.199.8%) and specificity of 84.2% (95% confidence interval 62.494.4%).

CONCLUSION

The study demonstrated the possibility of using GH level at 24 after surgery as a predictor for acromegaly remission. GH level 1.30 ng/ml at 24 hours after surgery showed better predictive value for long-term remission compared with the presence of microadenomas and Knosp Grade 02. The absence of decrease of GH level on the first day after surgery may serve as a reason for more close monitoring of patients in the postoperative period. Further studies in a larger number of observers are required to confirm our findings.

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.

Normal Insulin-like Growth Factor 1 During Somatostatin Receptor Ligand Treatment Predicts Surgical Cure in Acromegaly

CONTEXT

Treatment with somatostatin receptor ligands (SRLs) is often given before pituitary surgery to patients with acromegaly.

OBJECTIVE

To study whether the response to treatment with SRLs is predictive of surgical outcome.

DESIGN

Retrospective, observational study.

SETTING

Tertiary care center.

PATIENTS

We investigated 272 patients with acromegaly who had been treated with an SRL between 1990 and 2018.

INTERVENTION

All patients underwent pituitary surgery performed by a skilled neurosurgeon.

MAIN OUTCOME MEASURE

Outcome of pituitary surgery in patients who had normalization of insulin-like growth factor 1 (IGF-1) levels during SRL therapy in comparison with patients who did not normalize IGF-1 levels.

RESULTS

Normalization of IGF-1 levels during SRL treatment occurred in 62 patients (22.8%) and was similar for the 3 different types of SRL (P = .88). Surgical remission occurred in 59.6% of the patients. Patients who normalized IGF-1 levels during SRL treatment had a higher probability of surgical cure than patients without IGF-1 normalization (83.9% vs 52.4%, respectively; P < .001). Multivariate analysis confirmed that lack of cavernous sinus invasion, small maximum tumor diameter, and IGF-1 normalization during SRL therapy were the only factors independently associated with a favorable surgical outcome.

CONCLUSIONS

Our study demonstrates that the normalization of IGF-1 levels during treatment with SRLs is an independent predictive factor of a favorable surgical outcome. The underlying mechanisms remain unclear, but an optimal response to medical therapy may be a characteristic of less aggressive tumors that are more likely to be entirely removed at surgery.

Preoperative Topical Estrogen Treatment vs Placebo in 244 Children With Midshaft and Posterior Hypospadias

PURPOSE

Urethral fistula and dehiscence are common after hypospadias surgery. Preoperative androgens have been considered to reduce these complications although this consideration is not evidence-based. Dermatologists have reported the benefits of topical estrogens on skin healing. We investigated whether the preoperative use of topical promestriene could reduce healing complications in hypospadias surgery. Our primary objective was to demonstrate a reduction of healing complications with promestriene vs placebo. Impact on reoperations and other complications, clinical tolerance, bone growth, and biological systemic effects of the treatment were also considered.

METHODS

We conducted a prospective, randomized, placebo-controlled, double-blind, parallel group trial between 2011 and 2015 in 4 French centers. One-stage transverse preputial island flap urethroplasty (onlay urethroplasty) was selected for severe hypospadias. Promestriene or placebo was applied on the penis for 2 months prior to surgery. The primary outcome was the presence of postoperative urethral fistula or dehiscence in the first year postsurgery. For safety reasons, hormonal and anatomical screenings were performed.

RESULTS

Out of 241 patients who received surgery, 122 patients were randomized to receive placebo, and 119 patients received promestriene. The primary outcome was unavailable for 11 patients. Healing complications were assessed at 16.4% (19/116) in the placebo vs 14.9% (17/114) in the promestriene arm, and the odds ratio adjusted on center was 0.93 (95% confidence interval 0.45-1.94), P = 0.86.

CONCLUSIONS AND RELEVANCE

Although we observed an overall lower risk of complications compared to previous publications, postsurgery complications were not different between promestriene and placebo, because of a lack of power of the study or the inefficacy of promestriene.

Real-life analysis of 280 patients with surgically treated acromegaly: a single-center experience from 2008 to 2015

OBJECTIVE

The purpose of this study was to analyze the clinical and biochemical outcome of consecutive patients with acromegaly after microscopic transsphenoidal surgery (MTS) at a single center over an 8-year period.

METHODS

A retrospective analysis of patients with acromegaly treated via MTS between 2008 and 2015 at the authors’ center was performed. The mean follow-up was 29 months (range 1–120 months). Parameters investigated included tumor size, pre- and postoperative insulin-like growth factor–I, growth hormone levels, pretreatment, perioperative complications, and clinical outcome.

RESULTS

A total of 280 patients with acromegaly were treated surgically at the authors’ center over the abovementioned time frame and were included in analyses. For 231 of these patients, complete follow-up data were available for evaluation. One hundred eighty-eight patients (81%) showed remission initially according to current criteria. So far, 23 of these patients relapsed in the further course, so that on follow-up 165 patients (71%) demonstrated full remission by surgery alone. Most patients in whom remission after surgery failed were treated with somatostatin receptor ligands and/or dopamine agonists as second-line treatment. The main postoperative complications included transient hyponatremia and diabetes insipidus (13/280; 4.6%). CSF leakage only occurred in 2 cases (2/280; 0.7%). No surgery-related death occurred.

CONCLUSIONS

The data underline the effectiveness of MTS in acromegaly. Many patients with recurrent disease or incomplete tumor resection can be successfully managed pharmacologically.

Octreotide-Resistant Acromegaly: Challenges and Solutions

Acromegaly is a rare and severe disease caused by an increased and autonomous secretion of growth hormone (GH), thus resulting in high circulating levels of insulin-like growth factor 1 (IGF-1). Comorbidities and mortality rate are closely related to the disease duration. However, in most cases achieving biochemical control means reducing or even normalizing mortality and restoring normal life expectancy. Current treatment for acromegaly includes neurosurgery, radiotherapy and medical therapy. Transsphenoidal surgery often represents the recommended first-line treatment. First-generation somatostatin receptor ligands (SRLs) are the drug of choice in patients with persistent disease after surgery and are suggested as first-line treatment for those ineligible for surgery. However, only about half of patients treated with octreotide (or lanreotide) achieve biochemical control. Other available drugs approved for clinical use are the second-generation SRL pasireotide, the dopamine agonist cabergoline, and the GH-receptor antagonist pegvisomant. In the present paper, we revised the current literature about the management of acromegaly, aiming to highlight the most relevant and recent therapeutic strategies proposed for patients resistant to first-line medical therapy. Furthermore, we discussed the potential molecular mechanisms involved in the variable response to first-generation SRLs. Due to the availability of different medical therapies, the choice for the most appropriate drug can be currently based also on the peculiar clinical characteristics of each patient.

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.