Granular cell tumour of the cavernous sinus: A rare cause of secondary trigeminal neuralgia

Background: Cavernous sinus tumours comprise 0.1-0.2% of all intracranial tumours, and are most commonly meningiomas or schwannomas. Central nervous system and cranial nerve granular cell tumours (GCTs) are extremely rare. We report the tenth case of a GCT arising from a cranial nerve, and the second case reported in a cavernous sinus location, and review the literature. Clinical presentation: A 67-year-old man presented with right sided trigeminal neuralgia. Imaging findings suggested a trigeminal schwannoma and he was treated with CyberKnife radiosurgery. Over a period of 41 months follow up, there was a progression in both symptoms and imaging findings, requiring debulking surgery. Histopathology identified a GCT. Conclusions: This is the first case of a cranial nerve GCT treated with stereotactic radiosurgery. Trigeminal nerve GCTs are a rare differential in cases of presumed schwannomas.

J. Utilization of volumetric magnetic resonance imaging for baseline and surveillance imaging in Neuro-oncology

The acquisition of volumetric post-contrast MRI has clear advantages in the interpretation of neuro-oncology studies but has yet to find its way into routine clinical practice beyond planning scans for surgery and radiotherapy. This commentary briefly highlights the benefits of these techniques whilst dispelling some of the perceived disadvantages.

SAT-474 Giant Prolactinoma Case Series Assessing Response on Initial Dose of Cabergoline

Background: Giant prolactinomas (GPs) are rare representing 2-3% of prolactinomas and only ~ 0.5% of all pituitary tumors. Various definitions have been proposed for GP but commonly accepted criteria is tumor dimension of ≥4 cm. GP is often associated with very high prolactin (PRL) ranging 1,000 -100,000 ng/ml, significant extrasellar extension and no concomitant growth hormone or ACTH secretion. Patients predominantly present with neurological symptoms rather than endocrine dysfunction, and so the primary goal of treatment is amelioration of neurological symptoms. The literature search reveals approximately 190 papers on this topic and most are single case reports or series describing only unusual clinical manifestations. Hence, evidence based recommendations for treatment are lacking. Dopamine agonist (DA) is considered first line of therapy, as these tumors are highly sensitive to medical therapy. Surgery and radiation may be warranted in special situations. Low starting doses of cabergoline (CAB) are generally recommended due to concern for complications of apoplexy and cerebrospinal fluid (CSF) leak from rapid tumor shrinkage. However, no recommendations for a specific starting dose exist. Objective: Individual tumor and hormonal response were assessed on 15 patients (pts) with GP on low dose CAB; 0.25-0.5 mg weekly to determine the effectiveness of DA therapy. Methods: 15 GP pts from two tertiary care centers, meeting the diagnostic criteria mentioned above, were reviewed. Reduction in tumor volume and maximal tumor diameter along with PRL, after initiation of CAB, at or before 6 months and 1 year post diagnosis, was calculated. Results: Presenting symptom: visual disturbance (56%), headache (20%), apoplexy (13%) and incidental finding (6%). Mean age at diagnosis: 61 years. Male to Female: 4: 1. Basal prolactin concentration: >2000 ng/dl (12/15pts), and > 900 ng/ml (2/15). Initial total CAB dose/week: 0.25-0.5 mg (13/15) and 1-2 mg (2/15). Cranial surgery: 4/15. Complications: CSF leak (1/15). Tumor volume assessed at 6 months (11/15) and 1 year (4/15) along with decrease in maximum tumor diameter in the same period of time. PRL assessed at or before 6 months (13/15) and at 1 year (2/15). Improvement in tumor size occurred promptly even with low dose CAB (0.25-0.5mg/week). 100% of patients initiated on low dose CAB responded to therapy. Mean reduction in tumor volume at or before 6 months was 47% in 11/15, and 52% at 1 year (10/15). Mean decrease in maximal tumor dimension was calculated as 0.95 cm at 6 months (12/15) and 1.4 cm at 1 year (9/15). The overall prolactin response rate at or before 6 months was > 90% in 7/15 patients (53%) and >50% in 11/15 patients (73%). Conclusion: Our data confirms excellent tumor response to low dose cabergoline therapy. Dose as low at 0.25 mg twice weekly is proven to be effective, leading to decrease in both tumor volume and PRL levels.

194 Superovulation response does not affect embryo development of pronuclear microinjected embryos in the goat

Superovulation of donor animals is essential in the production of transgenic founder goats generated through microinjection. There can be a marked variable response to the exogenous hormones used for superovulation. The objective of this study was to examine how the superovulatory response of individual goats affected the ability of the fertilized, microinjected embryos to develop into offspring. The donors were superovulated using a progesterone implant on Day 0, a prostaglandin injection at Day 7, 2 injections ~12h apart of 32 to 36mg of FSH on Day 12 to 15, progesterone implant removal on Day 14, bred by intact bucks several times starting on Day 15 to 16, an injection of 50μg of gonadotropin-releasing hormone, and surgical collection of 1- to 2-cell embryos from retrograde flushing of the oviduct on Day 17 (~24-48 h, 1-2 days after breeding). Surgical collection allows for an accurate ovulation point (OP) count before the oviduct being retrograde flushed and ova collected and counted. Data from donor animals were grouped by superovulatory response based on OP counts of 1-10, 11-20, 21-30, or >30. The number of donors that contributed per group were 130, 280, 175, and 52, respectively. The recovery rate was 76, 72, 68, and 62%, respectively. After collection, ova were viewed under a dissecting microscope and assessed for fertilization by identifying pronuclei, and 1 pronucleus was microinjected. The fertilization rate was 47, 52, 51, and 56%, respectively. The survivability rate after microinjection was 80, 76, 75, and 76%, respectively. Surviving embryos were transferred (3-5) into recipient goats following a 2- to 6-h in vitro culture (as 1- to 2-cell embryos), allowing for a suitable period to assess viability post-injection. Further in vitro development rates were not assessed because of the short timeframe the embryos stayed in culture. The conception rates were 71, 56, 65, and 53%, respectively, and abortion rates were 23, 10, 14, and 9%, respectively. As some recipients received embryos from multiple donors, this data could not be included in the analysis as identifying which offspring were from the corresponding embryo group could not be confirmed. Data were analysed using SAS software (version 9.4, SAS Institute Inc., Cary, NC, USA). The Wald chi square test under linear regression was used to analyse the number of offspring produced per embryo transferred. No significant differences were found between groups (all P-values were>0.05). This analysis indicated that the range of superovulation response does not affect the developmental competence of the pronuclear microinjected embryo or the ability to produce viable offspring. Table 1.Comparison of the donor ovulation counts, number of embryos transferred, offspring produced and overall efficiency

94 Impact of number of embryos transferred on the number of offspring produced in a commercial transgenic founder production operation

The production of transgenic founder dairy goats (cross-bred Saanens, Alpines, Toggenburgs, and Nubians) involves the collection, microinjection, and transfer of numerous embryos into suitable recipient goats to ultimately produce a transgenic founder(s). The objective of this study was to determine the most efficient number of microinjection embryos to transfer to suitable recipients for transgenic founder generation. This is critically important in a commercial production program, as it impacts the goal for the number of embryos collected from donors, number of recipients utilised, and, hence, the overall number of surgical procedures being performed. The entire embryo collection, transfer, and founder-generation process is continuously being evaluated for ways to become more efficient in producing transgenic animals. During LFB USA’s commercial founder-production campaigns over the years (1997-2017), pronuclear microinjection was performed and 3, 4, or 5 embryos were transferred to female goat recipients. The recipients were synchronized using a progesterone implant on Day 0, a prostaglandin injection at Day 7, an injection of 300-500IU of pregnant mare serum gonadotropin on Day 13, progesterone implant removal on Day 14, and surgical transfer of pronuclear microinjected 1- or 2-cell embryos into the oviduct on Day 17. The individual totals and calculation for offspring per embryos transferred was compared for 3, 4, and 5 embryos transferred per recipient and was determined to be (1659/8637) 0.19, (912/4548) 0.20, and (112/675) 0.17, respectively. These embryo efficacy ratios were not significantly different (P>0.05) using the Wald Chi-squared test under logistic regression, and suggests that the number of offspring born is not impacted by number of embryos transferred. Seasonality was also evaluated in this production environment located in North America, with in-season being considered September to December and out-of-season being January to July. Nulliparous recipients during in-season (September to December) embryo transfer operations produced a significant difference, with totals and calculation for (offspring per embryo transferred) of (470/2346) 0.20, (260/1088) 0.24, and (23/190) 0.12 for 3, 4, and 5 embryo transfers, respectively (Table 1). This data indicates that when using nulliparous recipients during the in-season, transferring 4 embryos is optimal for offspring produced. Table 1.Comparison of the individual totals and the calculation of (offspring/embryo) by parity and season

Open reduction internal fixation vs non-operative management in proximal humerus fractures: a prospective, randomized controlled trial protocol

BACKGROUND

Proximal humerus fractures are the third most common fracture in the elderly population and are expected to increase due to the aging population. Surgical fixation with locking plate technology has increased over the last decade despite a lack of proven superiority in the literature. Three previous randomized controlled trials have not shown a difference in patient-centered outcomes when comparing non-operative treatment with open reduction and internal fixation. Low patient enrollment and other methodological concerns however limit the generalizability of these conclusions and as a result, management of these fractures remains a controversy. By comparing the functional outcomes of locked plate surgical fixation versus non-operative treatment of displaced three and four-part proximal humerus fractures in the elderly population with a large scale, prospective, multi-centered randomized controlled trial, the optimal management strategy for this common injury may be determined.

METHODS

We will conduct a prospective, single blind randomized controlled parallel arm trial to compare non-operative management of proximal humerus fractures with open reduction and internal fixation using locked plating technology. One-hundred and sixty patients > age 60 with acute 3- or 4- part proximal humerus fractures will be randomized to either open reduction and internal fixation with locked plating technology or non-operative management treatment arms. The primary outcome measure is the Constant Score at 24 months post-operative. Secondary outcome measures include the American Shoulder and Elbow Surgeon's Score (ASES), EuroQol EQ-5D-5 L Health Questionnaire Score, short form PROMIS upper extremity score and IPAQ for the elderly score. Further outcome measures include assessment of the initial classification, displacement and angulation and the quality of surgical reduction via a standard computed tomography (CT) scan; rates of non-union, malunion, arthrosis, osteopenia or other complications including infection, nerve injury, intra-articular screw penetration, reoperation rates and hospital re-admission rates.

DISCUSSION

The results of this trial will provide Level 1 evidence to guide decision-making in the treatment of proximal humerus fractures in the elderly population.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02362100 . Registered 5 Feb 2015.

Non-operative meningiomas: long-term follow-up of 136 patients

BACKGROUND

Improving access to neuroradiology investigations has led to an increased rate of diagnosis of incidental meningiomas.

METHOD

A cohort of 136 incidental meningioma patients collected by a single neurosurgeon in a single neurosurgical centre is retrospectively analysed between 2002 and 2016. Demographic data, imaging and clinical features are presented. The radiological factors associated with meningiomas progression are also presented.

RESULTS

The mean age at diagnosis was 65 (range, 33-94) years. Univariate analysis showed oedema was most strongly correlated with progression (p = 0.010) followed by hyperintensity in T2-weighted (T2W) MRI (p = 0.029) and in Flair-T2W MRI (p = 0.017). Isointensity in Flair-T2W MRI (0.004) was most strongly correlated with non-progression of the meningioma followed by calcification (p = 0.007), older age (p = 0.087), hypointensity in Flair-T2W MRI (p = 0.014) sequences and in T2W MRI (p = 0.096). In multivariate analysis, the strongest radiological factor predictive of progression was peritumoural oedema (p = 0.016) and that of non-progression was calcification (p = 0.002). At the end of the median follow-up (FU) of 43 (range, 4-150) months, 109 (80%) patients remained clinically stable, 13 (10%) became symptomatic and 14 (10%) showed clinical and radiological progression.

CONCLUSIONS

One hundred and nine (80%) patients remained stable at the end of FU. Peritumoural oedema was predictive of meningiomas progression. Further prospective study is needed to identify the combination of factors which can predict the meningioma progression for an early surgery or early discharge.

Complexity of Blocking Bivalent Protein-Protein Interactions: Development of a Highly Potent Inhibitor of the Menin-Mixed-Lineage Leukemia Interaction

The protein-protein interaction between menin and mixed-lineage leukemia 1 (MLL1) plays an important role in development of acute leukemia with translocations of the MLL1 gene and in solid tumors. Here, we report the development of a new generation of menin-MLL1 inhibitors identified by structure-based optimization of the thienopyrimidine class of compounds. This work resulted in compound 28 (MI-1481), which showed very potent inhibition of the menin-MLL1 interaction (IC₅₀ = 3.6 nM), representing the most potent reversible menin-MLL1 inhibitor reported to date. The crystal structure of the menin-28 complex revealed a hydrogen bond with Glu366 and hydrophobic interactions, which contributed to strong inhibitory activity of 28. Compound 28 also demonstrates pronounced activity in MLL leukemia cells and in vivo in MLL leukemia models. Thus, 28 is a valuable menin-MLL1 inhibitor that can be used for potential therapeutic applications and in further studies regarding the role of menin in cancer.

Abstract 250: Role of First Degree Atrioventricular Block and Long Term Mortality in U.S. Veterans With Atherothrombotic Risk Factors

Background: First-degree atrioventricular (AV) block [PR interval exceeding 200 milliseconds (ms)] on a 12-lead electrocardiogram is a common finding. Previous studies suggested that first-degree AVB has a benign prognosis, but more recent reports suggest that first-degree AVB may be associated with adverse outcomes. We investigated the relationship between PR interval and long term morality in U.S. Veterans with atherothrombotic risk factors.

Methods: We retrospectively collected and analyzed data from a Veterans Affairs (VA) medical center for consecutive patients (October 2001 to January 2005) who presented for coronary angiography.

Results: Of 1193 charts, 1082 had a PR interval reading recorded (mean = 172.5±30.5 ms; median = 168 ms [range 59-334]). Mean follow-up period was 103±52 months. Mean age was 63.2±10.8 years with 98% male. Mean body mass index was 30.0±5.9. The prevalence of selected comorbidities was: hypertension (88%), hyperlipidemia (79%), obstructive coronary artery disease (73%), diabetes mellitus (45%), smoker (39%), history of peripheral vascular disease (17%), and history of cerebrovascular accident (8%). Mean left ventricular ejection fraction was 47%±13%. Eighty-two percent were on beta-blockers (BB), and 25% were on calcium channel blockers (CCB) while intraventricular conduction delay was seen in 6%. In a comparison of patients with PR interval ≤200 ms (n=936) vs. >200 ms (n=146), long term mortality was higher with PR interval >200 ms (58.2% vs. 44.4%, p=0.002). Mortality rate was also higher with patients on BB or CCB vs. not on either (49.8% vs 39.7%, p=0.024). While PR interval was a significant univariate predictor of mortality, it was not significant when adjusted for the covariates listed above [not including BB and CCB] (odds ratio = 1.08 [95% Cl = 0.70 to 1.66], p = 0.73).

Conclusion: In this study of US Veterans with atherothrombotic risk factors, the long term mortality rate was higher with first-degree AV block. PR interval has prognostic value within this specific cohort.

Abstract 114: Relationship Between Duration of QRS Complex and Long Term Mortality in U.S. Veterans With Atherothrombotic Risk Factors

Background: The 12-lead electrocardiogram (ECG) remains a cost-effective diagnostic tool in risk stratification for cardiovascular disease. Little is known of the prognostic value of QRS duration but recent reports suggest that a prolonged QRS duration may be associated with adverse outcomes. We investigated the relationship between QRS duration and long term mortality in Veterans with atherothrombotic risk factors.

Methods: We retrospectively collected data from a Veterans Affairs (VA) medical center for consecutive patients (October 2001 to January 2005) to determine the long term mortality rates associated with different intervals of QRS duration in patients who presented for coronary angiography.

Results: Of the 1193 charts reviewed, 1186 had a QRS duration reading recorded. For these 1186 patients the mean follow-up period was 103±52 months. Mean age was 63.2±10.8 years with 98% male. Mean body mass index was 30.0±5.9. The prevalence of comorbidities was: hypertension (88%), hyperlipidemia (79%), obstructive coronary artery disease (73%), left ventricular hypertrophy (50.4%), diabetes mellitus (45%), peripheral vascular disease (17%), and cerebrovascular accident (8%). Mean left ventricular ejection fraction (LVEF) was 47±13%, and mean PR interval was 172.5±30.5 milliseconds (ms). Most patients were on beta-blocker (82%). Among patients with bundle branch blocks (BBB), left BBB was present in 4.6% and right BBB was present in 6.9%. Mean QRS duration was 102.2±23.6 ms. As the QRS duration increased by intervals of 10-milliseconds, the mortality rate (%) increased [QRS ≤100 (40.7%), 101 to 110 (51.3%), 111 to 120 (66.3%), >120 (71.2%), p<0.001]. Among patients with QRS duration >120, mortality was higher in those >150 vs. 121 to 150 (79.7% vs 65.7, p=0.045). While QRS duration was a significant univariate predictor of morality, QRS duration is not significant when adjusted for 10 covariates listed above (odds ratio = 1.00 [95% Cl = 0.98 to 1.01], p = 0.72).

Conclusion: Long term mortality was higher as QRS duration increased. QRS duration had utility in predicting mortality within this cohort of US Veterans with atherothrombotic risk factors.

Deep vein thrombosis resolution, recurrence and post-thrombotic syndrome: a prospective observational study protocol

Background

Reasons for the variation in response of deep vein thrombosis (DVT) to anticoagulation treatment are not known. Some patients develop complications such as post-thrombotic syndrome or recurrent DVT but others make a full recovery. The aim of the study is to identify the level of variation in response to anticoagulation treatment and provide more precise and quantitative disease characterisation in response to treatment.

Methods

A prospective observational study using duplex ultrasound to examine changes in thrombus characterisation, evolution and resolution over a 2 year period in patients with a confirmed DVT. Logistic regression analysis will be used to seek associations between characteristics present at baseline and the outcomes of DVT resolution, recurrence and the development of post-thrombotic syndrome (PTS).

Discussion

This research into the response to treatment of lower limb DVT and predictive factors for DVT resolution, recurrence and PTS could inform a more tailored approach to anticoagulation therapy for the future management of DVT.

UKCRN ID: 16016. Registered on 20 January 2014.

Spontaneous shrinkage of vestibular schwannoma

Background:

“Watch, wait, and rescan” (WWR) has an established place as a successful management option for a significant proportion of vestibular schwannomas (VS) as an alternative to microsurgical removal or stereotactic radiotherapy. VS may grow slowly and continuously, followed by stagnation or even shrinkage. We present two case reports of spontaneous shrinkage of VS along with a review of the literature.

Case Description:

A 29-year-old female presented with a progressive history of visual blurring and intermittent diplopia over 2 months. A 29 mm of maximum intracranial diameter (ICD) VS with secondary obstructive hydrocephalus was diagnosed. The patient underwent a ventriculo-peritoneal shunt with resolution of her symptoms and opted for initial WWR management. Interval scanning between 2007 and 2014 showed progressive reduction in the maximum ICD together with reduction in the degree of central tumor enhancement. Maximum ICD at most recent follow up was 22 mm. A 28-year-old female was referred with right sensorineural deafness. A right VS of maximum ICD of 27 mm was diagnosed. Initial WWR management was planned after discussion. Serial imaging showed an initial increase in the size of the tumor followed by progressive reduction in size. The most recent follow up showed a maximum ICD of 20 mm.

Conclusion:

Early WWR management can be associated with spontaneous shrinkage of VS over time. Prospective clinical study of larger numbers of such cases using the UK VS database may help to identify predictive factors for the spontaneous regression of VS.

Property Focused Structure-Based Optimization of Small Molecule Inhibitors of the Protein-Protein Interaction between Menin and Mixed Lineage Leukemia (MLL)

Development of potent small molecule inhibitors of protein-protein interactions with optimized druglike properties represents a challenging task in lead optimization process. Here, we report synthesis and structure-based optimization of new thienopyrimidine class of compounds, which block the protein-protein interaction between menin and MLL fusion proteins that plays an important role in acute leukemias with MLL translocations. We performed simultaneous optimization of both activity and druglike properties through systematic exploration of substituents introduced to the indole ring of lead compound 1 (MI-136) to identify compounds suitable for in vivo studies in mice. This work resulted in the identification of compound 27 (MI-538), which showed significantly increased activity, selectivity, polarity, and pharmacokinetic profile over 1 and demonstrated a pronounced effect in a mouse model of MLL leukemia. This study, which reports detailed structure-activity and structure-property relationships for the menin-MLL inhibitors, demonstrates challenges in optimizing inhibitors of protein-protein interactions for potential therapeutic applications.

A novel surgical approach for the management of giant invasive prolactinoma compressing the brainstem

Prolactinomas constitute the largest subsection of all secretory pituitary adenomas. Most are microprolactinomas and are satisfactorily treated by medical management alone. Giant prolactinomas, measuring more than 4 cm in diameter, are rare and usually occur more commonly in men. Macroprolatinomas tend to present with symptoms of mass effect rather than those of hyperprolactinaemia. Dopamine agonists (DA) are the treatment of choice for all prolactinomas. Surgery is usually reserved for DA resistance or if vision is threatened by the mass effects of the tumour. We describe the case of a 52 year-old woman with a giant invasive prolactinoma who required multiple surgical procedures as well as medical management with DA. One of the surgical interventions required a posterior approach via the trans cranial sub occipital transtentorial approach, a surgical technique that has not been previously described in the medical literature for this indication. The giant prolactinoma was reduced significantly with the above approach and patient symptoms from the compressing effects of the tumour were resolved. This case highlights the importance of a multidisciplinary approach to the management of such patients who present with florid neurological sequelae secondary to pressure effects. Although this presentation is uncommon, surgery via a sub occipital transtentorial approach may be considered the treatment of choice in suitable patients with giant invasive prolactinomas compressing the brainstem.