Upregulation of cell surface GD3 ganglioside phenotype is associated with human melanoma brain metastasis

Melanoma metastasis to the brain is one of the most frequent extracranial brain tumors. Cell surface gangliosides are elevated in melanoma metastasis; however, the metabolic regulatory mechanisms that govern these specific changes are poorly understood in melanoma particularly brain metastases (MBM) development. We found ganglioside GD3 levels significantly upregulated in MBM compared to lymph node metastasis (LNM) but not for other melanoma gangliosides. Moreover, we demonstrated an upregulation of ST8SIA1 (GD3 synthase) as melanoma progresses from melanocytes to MBM cells. Using RNA‐ISH on FFPE specimens, we evaluated ST8SIA1 expression in primary melanomas (PRM) (n = 23), LNM and visceral metastasis (n = 45), and MBM (n = 39). ST8SIA1 was significantly enhanced in MBM compared to all other specimens. ST8SIA1 expression was assessed in clinically well‐annotated melanoma patients from multicenters with AJCC stage III B‐D LNM (n = 58) with 14‐year follow‐up. High ST8SIA1 expression was significantly associated with poor overall survival (HR = 3.24; 95% CI, 1.19–8.86, P = 0.02). In a nude mouse human xenograft melanoma brain metastasis model, MBM variants had higher ST8SIA1 expression than their respective cutaneous melanoma variants. Elevated ST8SIA1 expression enhances levels of cell surface GD3, a phenotype that favors MBM development, hence associated with very poor prognosis. Functional assays demonstrated that ST8SIA1 overexpression enhanced cell proliferation and colony formation, whereby ST8SIA1 knockdown had opposite effects. Icaritin a plant‐derived phytoestrogen treatment significantly inhibited cell growth in high GD3‐positive MBM cells through targeting the canonical NFκB pathway. The study demonstrates GD3 phenotype associates with melanoma progression and poor outcome.

ICAR: endoscopic skull-base surgery

BACKGROUND

Endoscopic skull-base surgery (ESBS) is employed in the management of diverse skull-base pathologies. Paralleling the increased utilization of ESBS, the literature in this field has expanded rapidly. However, the rarity of these diseases, the inherent challenges of surgical studies, and the continued learning curve in ESBS have resulted in significant variability in the quality of the literature. To consolidate and critically appraise the available literature, experts in skull-base surgery have produced the International Consensus Statement on Endoscopic Skull-Base Surgery (ICAR:ESBS).

METHODS

Using previously described methodology, topics spanning the breadth of ESBS were identified and assigned a literature review, evidence-based review or evidence-based review with recommendations format. Subsequently, each topic was written and then reviewed by skull-base surgeons in both neurosurgery and otolaryngology. Following this iterative review process, the ICAR:ESBS document was synthesized and reviewed by all authors for consensus.

RESULTS

The ICAR:ESBS document addresses the role of ESBS in primary cerebrospinal fluid (CSF) rhinorrhea, intradural tumors, benign skull-base and orbital pathology, sinonasal malignancies, and clival lesions. Additionally, specific challenges in ESBS including endoscopic reconstruction and complication management were evaluated.

CONCLUSION

A critical review of the literature in ESBS demonstrates at least the equivalency of ESBS with alternative approaches in pathologies such as CSF rhinorrhea and pituitary adenoma as well as improved reconstructive techniques in reducing CSF leaks. Evidence-based recommendations are limited in other pathologies and these significant knowledge gaps call upon the skull-base community to embrace these opportunities and collaboratively address these shortcomings.

Downregulation of the Ubiquitin-E3 Ligase RNF123 Promotes Upregulation of the NF-κB1 Target SerpinE1 in Aggressive Glioblastoma Tumors

This study examined the role of the ubiquitin E3-ligase RNF123 in modulating downstream NF-κB1 targets in glioblastoma (GB) tumor progression. Our findings revealed an oncogenic pathway (miR-155-5p-RNF123-NF-κB1-p50-SerpinE1) that may represent a new therapeutic target pathway for GB patients with isocitrate dehydrogenase 1 and 2 (IDH) WT (wild type). Mechanistically, we demonstrated that RNF123 is downregulated in IDH WT GB patients and leads to the reduction of p50 levels. RNA-sequencing, reverse-phase protein arrays, and in vitro functional assays on IDH WT GB cell lines with RNF123 overexpression showed that SerpinE1 was a downstream target that is negatively regulated by RNF123. SERPINE1 knockdown reduced the proliferation and invasion of IDH WT GB cell lines. Both SerpinE1 and miR-155-5p overexpression negatively modulated RNF123 expression. In clinical translational analysis, RNF123, SerpinE1, and miR-155-5p were all associated with poor outcomes in GB patients. Multivariable analysis in IDH WT GB patients showed that concurrent low RNF123 and high SerpinE1 was an independent prognostic factor in predicting poor overall survival (p < 0.001, hazard ratio (HR) = 2.93, 95% confidence interval (CI) 1.7-5.05), and an increased risk of recurrence (p < 0.001, relative risk (RR) = 3.56, 95% CI 1.61-7.83).

Pituitary gland recovery following fully endoscopic transsphenoidal surgery for nonfunctioning pituitary adenoma: results of a prospective multicenter study

OBJECTIVE

Recovery from preexisting hypopituitarism after transsphenoidal surgery for pituitary adenoma is an important outcome to investigate. Furthermore, pituitary function has not been thoroughly evaluated after fully endoscopic surgery, and benchmark outcomes have not been clearly established. Here, the authors characterize pituitary gland outcomes with a focus on gland recovery following endoscopic transsphenoidal removal of clinically nonfunctioning adenomas.

METHODS

This multicenter prospective study was conducted at 6 US pituitary centers among adult patients with nonfunctioning pituitary macroadenomas who had undergone endoscopic endonasal pituitary surgery. Pituitary gland function was evaluated 6 months after surgery.

RESULTS

The 177 enrolled patients underwent fully endoscopic transsphenoidal surgery; 169 (95.5%) of them were available for follow-up. Ninety-five (56.2%) of the 169 patients had had a preoperative deficiency in at least one hormone axis, and 20/95 (21.1%) experienced recovery in at least one axis at the 6-month follow-up. Patients with adrenal insufficiency were more likely to recover (10/34 [29.4%]) than were those with hypothyroidism (8/72 [11.1%]) or male hypogonadism (5/50 [10.0%]). At the 6-month follow-up, 14/145 (9.7%) patients had developed at least one new deficiency. The study did not identify any predictors of gland recovery (p ≥ 0.20). Permanent diabetes insipidus was observed in 4/166 (2.4%) patients. Predictors of new gland dysfunction included a larger tumor size (p = 0.009) and Knosp grade 3 and 4 (p = 0.051).

CONCLUSIONS

Fully endoscopic pituitary surgery resulted in improvement of pituitary gland function in a substantial minority of patients. The deficiency from which patients were most likely to recover was adrenal insufficiency. Overall rates of postoperative permanent diabetes insipidus were low. This study provides multicenter benchmark neuroendocrine clinical outcome data for the endoscopic technique.

The Minimal Clinically Important Difference of the Anterior Skull Base Nasal Inventory-12

BACKGROUND

The minimal clinically important difference (MCID) is defined as the smallest change in health-related quality of life (QOL) that patients consider meaningful. The MCID is essential for determining clinically significant changes, rather than simply statistically significant changes, in QOL scores. The Anterior Skull Base Nasal Inventory-12 (ASK Nasal-12), a site-specific sinonasal QOL instrument, has emerged as a standard instrument for assessing QOL in patients who have undergone endonasal transsphenoidal surgery.

OBJECTIVE

To determine the MCID for the ASK Nasal-12.

METHODS

Distribution- and anchor-based methods were used to determine the MCID for the ASK Nasal-12 based on raw data from a multicenter prospective QOL study of 218 patients.

RESULTS

Two distribution-based statistical methods, the one-half standard deviation method and the effect-size method, both yielded MCIDs of 0.37 (medium effect). The first anchor-based method, using the 2-wk postoperative overall nasal functioning item as the anchor, yielded an MCID of 0.31. The second anchor-based method, using the 2-wk postoperative Short Form Health Survey 8 bodily pain item as the anchor, yielded an MCID of 0.29.

CONCLUSION

The largest MCID obtained for the ASK Nasal-12 using 4 statistical methods 2 wk postoperatively was 0.37. This information provides clinicians with an essential context for determining the clinical significance of changes in QOL scores after interventions. Our results will help clinicians better interpret QOL scores and design future studies that are powered to detect meaningful QOL changes.

Pituitary Apoplexy

Pituitary apoplexy is a clinical condition with acute-onset headaches, vision loss, and/or pituitary dysfunction associated with a hemorrhagic or infarcted pituitary tumor or cyst. Treatment varies based on clinical presentation, although often urgent or emergent surgical resection is indicated. Conservative treatment strategies tend to be applied for more mild conditions of apoplexy. Overall outcomes may be similar in this less severe cohort. Acute-onset vision loss with apoplexy should be treated with urgent or emergent surgical evacuation of hematoma and resection of tumor when possible.

Rathke's cleft cysts: a 6-year experience of surgery vs. observation with comparative volumetric analysis

BACKGROUND

Rathke's cleft cysts (RCCs) are common sellar lesions. Their management remains controversial, particularly when small or asymptomatic. Herein we review a consecutive series of RCC patients managed with surgery or observation.

METHODS

All patients with a new diagnosis of presumed RCC, based on MRI, from February 2012-March 2018 were retrospectively divided into observational and surgical cohorts based on an intent-to-treat model. The cohorts were compared for clinical presentation, and cyst volume. The observational cohort was followed for change in cyst size. The surgical cohort was followed for changes in endocrinopathy, visual symptoms, headache and recurrence.

RESULTS

Of 90 patients (mean age 36.7 ± 19.4 years; 68% female), 60% (n = 54) were in the observational cohort and 40% (n = 36) in the surgical cohort. Average follow-up was 13 ± 23 months in the observational cohort and 24 ± 19 months in the surgical group. In comparing the cohorts, mean ages were similar with more women in the surgical group (81% vs. 56%, p = 0.04). Most patients in the observational cohort had incidentally-discovered RCCs (n = 50, 88%) as opposed to the surgical cohort (n = 6, 17%). The surgical cohort had higher rates of headache (89% vs 26%, p < 0.001), endocrinopathy (36% vs 0%, p < 0.001), and visual dysfunction (19% vs 0%, p = 0.001). Mean cyst volume and maximal cyst dimensions were greater in the surgical cohort (0.94 ± 0.77 cm³ and 14.2 ± 4.1 mm), compared to the observational cohort (0.1 ± 0.14 cm³ and 6.4 ± 3 mm), (p < 0.001). Among the 53% (n = 30/54) of patients in the observational group with follow-up, 3 (10%) had spontaneous RCC shrinkage, 1 (3%) had modest asymptomatic growth (at 10 months from initial MRI), and 87% had stable cyst size. Of the 36 patients recommended to have surgery, 89% (n = 32) did so. Post-operatively, complete or partial resolution of headache, endocrinopathy and visual dysfunction were documented in 90% (n = 28/30), 75% (n = 10/12), and 100% (n = 7/7), respectively. On follow-up MRI, 8 (22%) patients had some cyst reaccumulation, of whom 3 (8%) were symptomatic and underwent uneventful reoperation. No major complications such as hematoma, CSF leak, new endocrinopathy or visual deficits occurred.

CONCLUSION

From this consecutive series, a majority (60%) of RCCs do not appear to warrant surgical intervention and have a low risk of cyst progression. However, surgical cyst removal appears to be indicated and safe for patients with larger, symptomatic RCCs. Simple cyst drainage has a high rate of improvement in pituitary gland function, visual function and headache resolution with low complication rates and symptomatic recurrence risk. These findings stress the importance of careful case selection and potential utility of volumetric assessment for patients with RCCs.

Correction to: Rathke's cleft cysts: a 6-year experience of surgery vs. observation with comparative volumetric analysis

The original version of this article unfortunately contained errors in legend numbers of Figure 2 caption.

Analysis of Olfaction after Bilateral Nasoseptal Rescue Flap Transsphenoidal Approach with Olfactory Mucosal Preservation

OBJECTIVE

To ascertain the impact of septal olfactory strip preservation and bilateral rescue flap elevation on the incidence of olfactory dysfunction.

STUDY DESIGN

Case series with chart review of patients undergoing endoscopic endonasal skull base surgery (2012-2014).

SETTING

Providence Saint John's Health Center and John Wayne Cancer Institute.

SUBJECTS AND METHODS

The incidences of postoperative epistaxis, hyposmia, and anosmia were analyzed using the Brief Smell Identification Test (B-SIT), which was completed in 110 of the 165 patients.

RESULTS

Seventy-eight patients required extended approaches. Bilateral nasoseptal rescue flaps were elevated in 144 patients (87.3%) and pedicled nasoseptal or middle turbinate flaps in 21 patients (12.7%). The neurovascular pedicles were preserved in all patients, and there were no episodes of postoperative arterial epistaxis. Normal olfaction was noted in 95 patients (86%), with new hyposmia noted in 5 patients (5.5%). Within the rescue flap cohort, new hyposmia occurred in 6.3% (P < .01) of patients, balanced by improvement of olfaction in 43% of patients with preoperative dysfunction (overall pre- and postoperative olfactory function: 85% vs 86%). Patients with pedicled nasoseptal flaps did not have new hyposmia, with a net improvement of olfaction (71% vs 86%, P = .07). No patients experienced new anosmia. There was no difference between flap type within either subgroup.

CONCLUSIONS

Superior olfactory strip preservation during elevation of reconstructive flaps preserves olfactory function and maintains adequate surgical exposure. In addition, rescue flaps have significantly diminished the rate of arterial postoperative epistaxis while maintaining the ability to harvest nasoseptal flaps for future reconstruction.

Somatostatin Receptor Ligand Therapy-A Potential Therapy for Neurocytoma

CONTEXT

Neurocytoma (NC) is a rare, low-grade tumor of the central nervous system, with a 10-year survival rate of 90% and local control rate of 74%. However, 25% of NCs will be atypical, with an elevated Ki-67 labeling index >2%, and will exhibit a more aggressive course, with a high propensity for local recurrence and/or craniospinal dissemination. Although no standard treatment regimen exists for these atypical cases, adjuvant stereotactic or conventional radiotherapy and/or chemotherapy have been typically offered but have yielded inconsistent results.

CASE DESCRIPTION

We have described the case of a patient with a vasopressin-secreting atypical NC of the sellar and cavernous sinus region. After subtotal resection via endoscopic transsphenoidal surgery, the residual tumor showed increased fluorodeoxyglucose uptake and high somatostatin receptor (SSTR) expression on a 68Ga-DOTA-TATE positron emission tomography/CT scan. Somatostatin receptor ligand (SRL) therapy with lanreotide (120 mg every 28 days) was initiated. Four years later, the residual tumor was stable with decreased fluorodeoxyglucose tumor uptake. Immunocytochemical SSTR2 and SSTR5 expression >80% was further confirmed in a series of NC tissues.

CONCLUSIONS

To the best of our knowledge, we have described the first use of SRL therapy for an atypical NC. Our results support consideration of adjuvant SRL therapy for NC refractory to surgical removal. Our findings further raise the possibility of SSTR-directed peptide receptor radionuclide therapy as NC therapy.

Evaluation of Surgical Resection Goal and Its Relationship to Extent of Resection and Patient Outcomes in a Multicenter Prospective Study of Patients With Surgically Treated, Nonfunctioning Pituitary Adenomas: A Case Series

BACKGROUND

The influence of the surgeon's preoperative goal regarding the extent of tumor resection on patient outcomes has not been carefully studied among patients with nonfunctioning pituitary adenomas.

OBJECTIVE

To analyze the relationship between surgical tumor removal goal and patient outcomes in a prospective multicenter study.

METHODS

Centrally adjudicated extent of tumor resection (gross total resection [GTR] and subtotal resection [STR]) data were analyzed using standard univariate and multivariable analyses.

RESULTS

GTR was accomplished in 148 of 171 (86.5%) patients with planned GTR and 32 of 50 (64.0%) patients with planned STR (P = .001). Sensitivity, specificity, positive predictive value, and negative predictive value of GTR goal were 82.2, 43.9, 86.5, and 36.0%, respectively. Knosp grade 0-2, first surgery, and being an experienced surgeon were associated with surgeons choosing GTR as the goal (P &lt; .01). There was no association between surgical goal and presence of pituitary deficiency at 6 mo (P = .31). Tumor Knosp grade (P = .004) and size (P = .001) were stronger predictors of GTR than was surgical goal (P = .014). The most common site of residual tumor was the cavernous sinus (29 of 41 patients; 70.1%).

CONCLUSION

This is the first pituitary surgery study to examine surgical goal regarding extent of tumor resection and associated patient outcomes. Surgical goal is a poor predictor of actual tumor resection. A more aggressive surgical goal does not correlate with pituitary gland dysfunction. A better understanding of the ability of surgeons to meet their expectations and of the factors associated with surgical result should improve prognostication and preoperative counseling.

Results of a prospective multicenter controlled study comparing surgical outcomes of microscopic versus fully endoscopic transsphenoidal surgery for nonfunctioning pituitary adenomas: the Transsphenoidal Extent of Resection (TRANSSPHER) Study

OBJECTIVE

Many surgeons have adopted fully endoscopic over microscopic transsphenoidal surgery for nonfunctioning pituitary tumors, although no high-quality evidence demonstrates superior patient outcomes with endoscopic surgery. The goal of this analysis was to compare these techniques in a prospective multicenter controlled study.

METHODS

Extent of tumor resection was compared after endoscopic or microscopic transsphenoidal surgery in adults with nonfunctioning adenomas. The primary end point was gross-total tumor resection determined by postoperative MRI. Secondary end points included volumetric extent of tumor resection, pituitary hormone outcomes, and standard quality measures.

RESULTS

Seven pituitary centers and 15 surgeons participated in the study. Of the 530 patients screened, 260 were enrolled (82 who underwent microscopic procedures, 177 who underwent endoscopic procedures, and 1 who cancelled surgery) between February 2015 and June 2017. Surgeons who used the microscopic technique were more experienced than the surgeons who used the endoscopic technique in terms of years in practice and number of transsphenoidal surgeries performed (p < 0.001). Gross-total resection was achieved in 80.0% (60/75) of microscopic surgery patients and 83.7% (139/166) of endoscopic surgery patients (p = 0.47, OR 0.8, 95% CI 0.4-1.6). Volumetric extent of resection, length of stay, surgery-related deaths, and unplanned readmission rates were similar between groups (p > 0.2). New hormone deficiency was present at 6 months in 28.4% (19/67) of the microscopic surgery patients and 9.7% (14/145) of the endoscopic surgery patients (p < 0.001, OR 3.7, 95% CI 1.7-7.7). Microscopic surgery cases were significantly shorter in duration than endoscopic surgery cases (p < 0.001).

CONCLUSIONS

Experienced surgeons who performed microscopic surgery and less experienced surgeons who performed endoscopic surgery achieved similar extents of tumor resection and quality outcomes in patients with nonfunctioning pituitary adenomas. The endoscopic technique may be associated with lower rates of postoperative pituitary gland dysfunction. This study generally supports the transition to endoscopic pituitary surgery when the procedure is performed by proficient surgeons, although both techniques yield overall acceptable surgical outcomes.■ CLASSIFICATION OF EVIDENCE Type of question: therapeutic; study design: prospective cohort trial; evidence: class III.Clinical trial registration no.: NCT02357498 (clinicaltrials.gov).

Analysis of cell-free circulating tumor DNA in 419 patients with glioblastoma and other primary brain tumors

Aim:

Genomically matched trials in primary brain tumors (PBTs) require recent tumor sequencing. We evaluated whether circulating tumor DNA (ctDNA) could facilitate genomic interrogation in these patients.

Methods:

Data from 419 PBT patients tested clinically with a ctDNA NGS panel at a CLIA-certified laboratory were analyzed.

Results:

A total of 211 patients (50%) had ≥1 somatic alteration detected. Detection was highest in meningioma (59%) and gliobastoma (55%). Single nucleotide variants were detected in 61 genes, with amplifications detected in ERBB2, MET, EGFR and others.

Conclusion:

Contrary to previous studies with very low yields, we found half of PBT patients had detectable ctDNA with genomically targetable off-label or clinical trial options for almost 50%. For those PBT patients with detectable ctDNA, plasma cfDNA genomic analysis is a clinically viable option for identifying genomically driven therapy options.

Pregnancy-associated Cushing's disease? An exploratory retrospective study

PURPOSE

In most clinical series of Cushing's disease (CD), over 80% of patients are women, many of whom are of reproductive age. The year following pregnancy may be a common time to develop CD. We sought to establish the incidence of CD onset associated with pregnancy.

METHODS

A retrospective review was conducted for patients with biochemically-proven CD. Demographics, clinical history, biochemistry, imaging, pathology, and outcomes were reviewed. Pregnancy-associated CD was defined as symptom onset within 1 year of childbirth.

RESULTS

Over 10 years, 77 patients including 64 women (84%), with CD underwent endonasal surgery. Of the 64 women, 64% were of reproductive age (15-45 years) at the time of diagnosis, and 11 (27%) met criteria for pregnancy-associated CD. Of these 11 women, median number of pregnancies prior to onset of CD was 2 (range 1-4) compared to zero (range 0-7) for 30 other women with CD onset during reproductive age (p = 0.0024). With an average follow-up of 47 ± 34 months, sustained surgical remission rates for woman with pregnancy-associated CD, other women of reproductive age, and women not of reproductive age were 91%, 80% and 83%, respectively. The average lag-time from symptom onset to diagnosis for women with pregnancy-associated CD was 4 ± 2 years.

CONCLUSIONS

In this exploratory study, over one quarter of women of reproductive age with CD appeared to have symptomatic disease onset within 1 year of childbirth. This relatively high rate of pregnancy-associated CD suggests a possible causal relationship related to the stress of pregnancy and pituitary corticotroph hyperactivity in the peripartum period. This possible association suggests a heightened degree of clinical suspicion and biochemical testing for CD may be warranted after childbirth. Further study of this possible link between pregnancy and CD is warranted.

Epigenetic profiling for the molecular classification of metastatic brain tumors

Optimal treatment of brain metastases is often hindered by limitations in diagnostic capabilities. To meet this challenge, here we profile DNA methylomes of the three most frequent types of brain metastases: melanoma, breast, and lung cancers (n = 96). Using supervised machine learning and integration of DNA methylomes from normal, primary, and metastatic tumor specimens (n = 1860), we unravel epigenetic signatures specific to each type of metastatic brain tumor and constructed a three-step DNA methylation-based classifier (BrainMETH) that categorizes brain metastases according to the tissue of origin and therapeutically relevant subtypes. BrainMETH predictions are supported by routine histopathologic evaluation. We further characterize and validate the most predictive genomic regions in a large cohort of brain tumors (n = 165) using quantitative-methylation-specific PCR. Our study highlights the importance of brain tumor-defining epigenetic alterations, which can be utilized to further develop DNA methylation profiling as a critical tool in the histomolecular stratification of patients with brain metastases.

Visual Field Outcome Reporting in Neurosurgery: Lessons Learned from a Prospective, Multicenter Study of Transsphenoidal Pituitary Surgery

OBJECTIVE

Visual field (VF) outcomes are commonly reported in neurosurgical case series; however, substantial variability can exist in VF testing and outcome reporting. We aimed to evaluate the challenges of VF testing and to develop detailed recommendations for VF outcome reporting by analyzing results from an ongoing, multicenter study of transsphenoidal pituitary surgery.

METHODS

VF testing results were collected during a prospective, multicenter clinical trial evaluating patient outcomes after transsphenoidal surgery for nonfunctioning pituitary adenomas (TRANSSPHER). Two independent ophthalmologists reviewed reliability and outcomes of all VF studies. Preoperative and postoperative VF studies were evaluated individually and as preoperative/postoperative pairs.

RESULTS

Suboptimal perimetry field settings were reported in 37% of VF studies. Automated reliability criteria flagged 25%-29% of VF studies as unreliable, whereas evaluation by 2 independent ophthalmologists flagged 16%-28%. Agreement between automated criteria and raters for VF reliability was inconsistent (κ coefficients = 0.55-0.83), whereas agreement between the 2 raters was substantial to almost perfect (κ coefficients = 0.78-0.83). Most patients demonstrated improvement after surgery (rater 1, 67%; rater 2, 60%), with substantial rater agreement on outcomes for paired examinations (κ coefficient = 0.62).

CONCLUSIONS

VF outcome studies demonstrated significant variability of test parameters and patient performance. Perimetry field settings varied among patients and for some patients varied preoperatively versus postoperatively. Reliance on automated criteria alone could not substitute for independent ophthalmologist review of test reliability. Standardized guidelines for VF data collection and reporting could increase reliability of results and allow better comparisons of outcomes in future studies.

The Epigenomic Landscape of Pituitary Adenomas Reveals Specific Alterations and Differentiates Among Acromegaly, Cushing's Disease and Endocrine-Inactive Subtypes

Purpose: Pituitary adenomas are one of the most common benign neoplasms of the central nervous system. Although emerging evidence suggests roles for both genetic and epigenetic factors in tumorigenesis, the degree to which these factors contribute to disease remains poorly understood.Experimental Design: A multiplatform analysis was performed to identify the genomic and epigenomic underpinnings of disease among the three major subtypes of surgically resected pituitary adenomas in 48 patients: growth hormone (GH)-secreting (n = 17), adrenocorticotropic hormone (ACTH)-secreting (n = 13, including 3 silent-ACTH adenomas), and endocrine-inactive (n = 18). Whole-exome sequencing was used to profile the somatic mutational landscape, whole-transcriptome sequencing was used to identify disease-specific patterns of gene expression, and array-based DNA methylation profiling was used to examine genome-wide patterns of DNA methylation.Results: Recurrent single-nucleotide and small indel somatic mutations were infrequent among the three adenoma subtypes. However, somatic copy-number alterations (SCNA) were identified in all three pituitary adenoma subtypes. Methylation analysis revealed adenoma subtype-specific DNA methylation profiles, with GH-secreting adenomas being dominated by hypomethylated sites. Likewise, gene-expression patterns revealed adenoma subtype-specific profiles. Integrating DNA methylation and gene-expression data revealed that hypomethylation of promoter regions are related with increased expression of GH1 and SSTR5 genes in GH-secreting adenomas and POMC gene in ACTH-secreting adenomas. Finally, multispectral IHC staining of immune-related proteins showed abundant expression of PD-L1 among all three adenoma subtypes.Conclusions: Taken together, these data stress the contribution of epigenomic alterations to disease-specific etiology among adenoma subtypes and highlight potential targets for future immunotherapy-based treatments. This article reveals novel insights into the epigenomics underlying pituitary adenomas and highlights how differences in epigenomic states are related to important transcriptome alterations that define adenoma subtypes. Clin Cancer Res; 24(17); 4126-36. ©2018 AACR.

Imaging-Ambiguous Lesions of Meckel's Cave-Utility of Endoscopic Endonasal Transpterygoid Biopsy

INTRODUCTION

Meckel's cave is a dural-lined cavity in the middle fossa skull base in which lies the Gasserian ganglion, a potential site for tumors and inflammatory lesions. A variety of lesions can be predominantly isolated to Meckel's cave, including extension from head and neck cancers, other malignant tumors, as well as benign lesions. Clinical presentation and imaging findings are often insufficient to establish a diagnosis. Hence, histologic confirmation is required to determine the appropriate treatment strategy. Several surgical approaches have been used to reach this deep-seated area, often with significant morbidity and prolonged recovery. Given advancements in endoscopy and greater facility with the technique, the endoscopic endonasal approach has been used increasingly to reach lesions in the region.

METHODS

A single-institution, retrospective chart review over a 10-year period was performed to identify and describe patients with pathologically differing but imaging-similar lesions with their epicenter in Meckel's cave.

RESULTS

Of a total of 21 cases of lesions in Meckel's cave approached by an endoscopic endonasal transpterygoid approach, we present 6 patients with imaging-ambiguous lesions involving Meckel's cave that were biopsied via the extended endoscopic endonasal approach. Among this diverse group, pathology included B-cell lymphoma, squamous cell carcinoma, adenocarcinoma, malignant schwannoma, benign schwannoma, and neurosarcoidosis.

CONCLUSIONS

We explore not only the relevance of this approach in the armamentarium of the modern skull-base surgeon but also its limitations and conclude that the endoscopic endonasal approach provides a safe and relatively direct, minimally invasive corridor to many lesions of Meckel's cave.

Safety of commercial airflight in patients with brain tumors: a case series

INTRODUCTION

Patients with intracranial masses are often advised to avoid airflight due to concerns of worsening neurological symptoms or deterioration. However, many patients often travel cross-country or internationally to tertiary care centers for definitive care. This study assesses the safety of commercial airflight for brain and skull base tumor patients without severe or progressive neurological deficits.

METHODS

Patients that had traveled to our institution for surgery via commercial airflight from 2014 to 2017 were identified. An electronic survey was administered (RedCap) and flight duration, aircraft type, presenting symptoms and new or worsened peri-flight symptoms were queried. Severity was assessed using visual analogue scale (VAS). Significant change of symptoms was determined to be greater than 25%. Demographics and clinical history were obtained from electronic medical records. Providence Health System IRB: 16-168.

RESULTS

Of 665 patients operated on for brain tumor, 63 (9.5%) traveled by airflight to our center for surgery and of these, 41 (65%) completed the study (mean age 48.5 ± 16.8 years, 63% female). Pathology included pituitary and other parasellar tumors (58%), meningiomas (22%), metastatic tumors (5%), gliomas (5%), pineal tumor (5%), cerebello-pontine tumor (5%). Average tumor volume was 11.4 cc and average maximal dimension was 2.7 cm. Ten (24.4%) patients developed worsened symptoms during airflight including: headaches 3/19 (15.8%), fatigue 3/14 (21.4%), dizziness 3/5 (60%) and ear pain 3/3 (100%), as well as one patient who had new onset seizures inflight. Seven patients (70%) sustained worsened symptoms after airflight. There were no permanent neurological deficits related to airflight. There was no correlation with tumor size, volume, location or flight duration with development of neurological symptoms. There was an inverse correlation between peri-flight corticosteroid usage and symptom exacerbation (p = 0.048). No patient with completely asymptomatic tumors developed new symptoms during flight.

CONCLUSIONS

Most patients with brain and skull base tumors can travel safely via commercial airflight with acceptable symptom exacerbation. However, consideration should be given to administering corticosteroids and possibly anticonvulsants to patients who are symptomatic and/or have relatively large tumors with mass effect and peritumoral edema.

Evolution of the graded repair of CSF leaks and skull base defects in endonasal endoscopic tumor surgery: trends in repair failure and meningitis rates in 509 patients

Objective

The authors previously described a graded approach to skull base repair following endonasal microscopic or endoscope-assisted tumor surgery. In this paper they review their experience with skull base reconstruction in the endoscopic era.

Methods

A retrospective review of a single-institution endonasal endoscopic patient database (April 2010–April 2017) was undertaken. Intraoperative CSF leaks were graded based on size (grade 0 [no leak], 1, 2, or 3), and repair technique was documented across grades. The series was divided into 2 epochs based on implementation of a strict perioperative antibiotic protocol and more liberal use of permanent and/or temporary buttresses; repair failure rates and postoperative meningitis rates were assessed for the 2 epochs and compared.

Results

In total, 551 operations were performed in 509 patients for parasellar pathology, including pituitary adenoma (66%), Rathke’s cleft cyst (7%), meningioma (6%), craniopharyngioma (4%), and other (17%). Extended approaches were used in 41% of cases. There were 9 postoperative CSF leaks (1.6%) and 6 cases of meningitis (1.1%). Postoperative leak rates for all 551 operations by grade 0, 1, 2, and 3 were 0%, 1.9%, 3.1%, and 4.8%, respectively. Fat grafts were used in 33%, 84%, 97%, and 100% of grade 0, 1, 2, and 3 leaks, respectively. Pedicled mucosal flaps (78 total) were used in 2.6% of grade 0–2 leaks (combined) and 79.5% of grade 3 leaks (60 nasoseptal and 6 middle turbinate flaps). Nasoseptal flap usage was highest for craniopharyngioma operations (80%) and lowest for pituitary adenoma operations (2%). Two (3%) nasoseptal flaps failed. Contributing factors for the 9 repair failures were BMI ≥ 30 (7/9), lack of buttress (4/9), grade 3 leak (4/9), and postoperative vomiting (4/9). Comparison of the epochs showed that grade 1–3 repair failures decreased from 6/143 (4.1%) to 3/141 (2.1%) and grade 1–3 meningitis rates decreased from 5 (3.5%) to 1 (0.7%) (p = 0.08). Prophylactic lumbar CSF drainage was used in only 4 cases (< 1%), was associated with a higher meningitis rate in grades 1–3 (25% vs 2%), and was discontinued in 2012. Comparison of the 2 epochs showed increase buttress use in the second, with use of a permanent buttress in grade 1 and 3 leaks increasing from 13% to 55% and 32% to 76%, respectively (p < 0.001), and use of autologous septal/keel bone as a permanent buttress in grade 1, 2, and 3 leaks increasing from 15% to 51% (p < 0.001).

Conclusions

A graded approach to skull base repair after endonasal surgery remains valid in the endoscopic era. However, the technique has evolved significantly, with further reduction of postoperative CSF leak rates. These data suggest that buttresses are beneficial for repair of most grade 1 and 2 leaks and all grade 3 leaks. Similarly, pedicled flaps appear advantageous for grade 3 leaks, while CSF diversion may be unnecessary and a risk factor for meningitis. High BMI should prompt an aggressive multilayered repair strategy. Achieving repair failure and meningitis rates lower than 1% is a reasonable goal in endoscopic skull base tumor surgery.