O14 Semi-quantitative assessment of synovial inflammation on US guided synovial membrane biopsy is contingent to disease phase, autoimmune profile and treatment response in RA: a large single center experience

Background

Ultrasound (US)-guided minimally-invasive synovial tissue (ST) biopsy is a well-tolerated procedure for basic and translational studies on chronic inflammatory joint diseases as rheumatoid arthritis (RA), psoriatic arthritis (PsA) and spondyloarthritis (SpA). The aim of the study was to evaluate the utility of histopathologic criteria to differentiate US-guided ST biopsies in daily clinical care in relation to diagnosis, disease characteristics, US parameters and treatment response in a large single center ST biopsy unit.

Methods

1,064 patients [545 RA, 167 PsA, 75 SpA, 199 undifferentiated peripheral inflammatory arthritis (UPIA), 18 crystal arthritis, 26 connective tissue diseases and 34 osteoarthritis (OA) respectively] who underwent US-guided ST biopsy were enrolled. US parameters (Synovial Hyperthrophy and Power Doppler signal respectively) were recorded for each biopsied joint. RA, PsA and SpA patients were stratified based on disease activity phase (naive to DMARDs, DMARDs resistant and in sustained remission, respectively). Clinical, demographic and immunological characteristics were recorded for each patient. All ST FFPE specimens were routinely processed and stained with H&E and classified by a pathologist, blinded to clinical characteristics, using the Krenn score to assess the degree of ST inflammation. Moreover, the presence/absence of lymphocytes, plasmacells, granulocytes and oedema was assessed for each ST. All naive to treatment RA were treated according to the T2T scheme and followed for at least 12 months and DAS remission rate was recorded.

Results

In the cohort, the distribution of synovitis score was significantly different among patients with inflammatory chronic diseases (RA, PsA, SpA and UPIA respectively) compared to OA (ANOVA Test p < 0.001). Moreover, Krenn score directly correlated with synovial hyperthrophy (R = 0.36; p < 0.001) and Power Doppler signal (R = 0.40;p<0.001) of the biopsied joint. Considering the RA cohort, naive RA showed a higher Krenn score compared to resistant RA (p < 0.001) and RA in sustained clinical and US remission (p < 0.001), directly correlating with DAS28 (R = 0.51; p < 0.001). Moreover, ACPA and RF positivity was related to the Krenn score and to ST plasmacells presence at RA onset (p < 0.05 and p < 0.001, respectively) but not at the time of DMARDs-failure or sustained remission achievement (p > 0.05 for both). Stratifying naive RA based on disease duration at ST biopsy, naive RA with symptoms duration >1 year, showed higher Krenn score compared to those with symptoms duration <3 months (p < 0.001). Finally, logistic regression analysis revealed that Krenn score higher or equal to 4.5 at baseline is an independent factor of no DAS remission achievement within 12 months [OR(95%CI):0.37(0.20-0.67)p<0.001] in naive RA.

Conclusion

Krenn score is a reliable tool for the semi-quantitative assessment of ST inflammation on US-guided ST biopsies being differentially distributed among various chronic inflammatory joint diseases and contingent to disease phase, autoimmune profile and therapeutic response in RA.

Disclosures

S. Alivernini None. B. Tolusso None. M. Gessi None. M. Gigante None. L. Petricca None. C. Di Mario None. S. Perniola None. A. Fedele None. G. Peluso None. L. Bui None. A. Capacci None. F. Federico None. G. Ferraccioli None. E. Gremese None.

Lumbar Extraosseous Intraforaminal Osteoblastoma: Case Report and Review of the Literature

BACKGROUND

Osteoblastomas are rare primary bone tumors with a predilection for the spine. The extraosseous growth pattern is rare, and to our knowledge, only 2 cases of fully extraosseous osteoblastomas have been previously reported.

CASE DESCRIPTION

A man aged 36 years presented with a 7-month history of low back pain radiating to the gluteal area. On examination, a typical L5 radiculopathy was noted. The radiologic examinations conducted in the previous months pointed out the rapid growth of an extraosseous mass occluding the right L5-S1 foramen. Partial laminectomy was performed to achieve gross total resection. Histological analysis was consistent with osteoblastoma.

CONCLUSIONS

Osteoblastomas with extraosseous extension are uncommon, and an exclusively extraosseous presentation is anecdotal. This can lead to preoperative misdiagnosis when typical radiologic characteristics of bone-forming tumors are missing. We describe the case of an extraosseous lumbar osteoblastoma whose clinical and radiologic presentation was suggestive of malignancy.

Role of susceptibility-weighted imaging and intratumoral susceptibility signals in grading and differentiating pediatric brain tumors at 1.5 T: a preliminary study

PURPOSE

Susceptibility-weighted imaging (SWI) is useful for glioma grading and discriminating between brain tumor categories in adults, but its diagnostic value for pediatric brain tumors is unclear. Here we evaluated the usefulness of SWI for pediatric tumor grading and differentiation by assessing intratumoral susceptibility signal intensity (ITSS).

METHODS

We retrospectively enrolled 96 children with histopathologically diagnosed brain tumors, who underwent routine brain MRI exam with SWI (1.5 T scanner). Each tumor was assigned an ITSS score by a radiology resident and an experienced neuroradiologist, and subsequently by consensus. Statistical analyses were performed to differentiate between low-grade (LG) and high-grade (HG) tumors, histological categories, and tumor locations. Inter-reader agreement was assessed using Cohen's kappa (κ).

RESULTS

The interobserver agreement was 0.844 (0.953 between first reader and consensus, and 0.890 between second reader and consensus). Among all tumors, we found a statistically significant difference between LG and HG for ITSS scores of 0 and 2 (p = 0.002). This correlation was weaker among astrocytomas alone, and became significant when considering only off-midline astrocytomas (p = 0.05). Scores of 0 and 2 were a strong discriminating factor (p = 0.001) for astrocytomas (score 0) and for embryonal, choroid plexus, germ-cell, pineal, and ependymoma tumors (score 2). No medulloblastoma showed a score of 0.

CONCLUSIONS

Our preliminary ITTS results in pediatric brain tumors somewhat differed from those obtained in adult populations. These findings highlight the potential valuable role of ITSS for tumor grading and discriminating between some tumor categories in the pediatric population.

Tumour-infiltrating cytotoxic T lymphocytes in somatotroph pituitary neuroendocrine tumours

INTRODUCTION

Somatotroph pituitary tumours are often resistant to first-generation somatostatin analogues and can invade the surrounding structures, limiting the chances of curative surgery. Recent studies suggested that the immune microenvironment and pro-angiogenic factors can influence neuroendocrine tumour prognosis. In this study, we aimed to investigate the prognostic role of immune cell-specific markers and endocan, a proteoglycan involved in neoangiogenesis and cell adhesion, in a cohort of acromegaly patients who underwent pituitary surgery as first-line treatment.

SUBJECTS AND METHODS

Sixty four eligible subjects were identified. CD4+, CD8+ and CD68+ cells and endocan expression were evaluated by immunohistochemistry and results correlated with clinical and neuroradiological findings. Responsiveness to somatostatin analogues was assessed in patients with persistent disease following surgery.

RESULTS

The number of CD8+ lymphocytes was significantly lower in tumours with cavernous sinus invasion (median 0.2/HPF, IQR: 2.2) compared with those without cavernous sinus invasion (median 2.4/HPF, IQR: 2.3; P = 0.04). Tumours resistant to first-generation somatostatin analogues had lower CD8+ lymphocytes (median 1/HPF, IQR: 2.4) compared with responders (median 2.4/HPF, IQR: 2.9; P = 0.005). CD4+ lymphocytes were observed sporadically. The number of CD68+ macrophages and the endothelial or tumour cell endocan expression did not differ based on tumour size, cavernous sinus invasion or treatment responsiveness.

CONCLUSIONS

Our study suggests that a lower number of CD8+ lymphocytes is associated with cavernous sinus invasion and resistance to treatment with first-generation somatostatin analogues in acromegaly patients. These results highlight a potential role of the tumour immune microenvironment in determining the prognosis of somatotroph pituitary tumours.

Pasireotide and Pegvisomant Combination Treatment in Acromegaly Resistant to Second-Line Therapies: A Longitudinal Study

CONTEXT

The treatment of acromegaly resistant to first- and second-line therapies can be extremely challenging.

DESIGN

We have described six patients who were successfully treated with a combination therapy of pasireotide and pegvisomant and compared them with a control group of patients resistant to conventional somatostatin analogs (SSAs), whose disease was controlled with other treatment, such as pasireotide (as monotherapy) or pegvisomant (as monotherapy or combined with conventional SSAs).

RESULTS

In these six patients, acromegaly was controlled with combined pasireotide and pegvisomant treatment after failure of all other treatments. Compared with the 49 patients in the control group, these six patients had giant and invasive pituitary adenomas (at both the cavernous sinus and other structures). Although not statistically significant, higher growth hormone levels, more elevated Ki-67 expression, greater somatostatin receptor (SSTR) subtype 5 expression, and lower SSTR subtype 2 expression at the diagnosis of acromegaly were detected in patients receiving combination treatment with pasireotide and pegvisomant compared with the control group.

CONCLUSION

Our data have reinforced the importance of personalized treatment of patients with acromegaly according to the clinical, biochemical, molecular, and morphological disease markers and suggest that combined treatment with pasireotide and pegvisomant can induce disease control in tumors with low SSTR2 expression, resistant to conventional SSAs (alone or combined with pegvisomant) and to new-generation SSAs alone (pasireotide).

SUN-LB076 Potential Role of Gallium-68-Peptides and Fluorine-18-FDG PET/CT and Ki67 in Patients with Post-Surgical Residual Pituitary Adenoma

Purpose: Pituitary adenomas are in most of cases benign lesions. However, in around 25% of cases they can show aggressive behavior, such invasiveness of pituitary region surrounding structures, progressive or rapid increase in size or evolvement in pituitary carcinoma. In recent years, 68Ga-peptides and 18F-FDG PET/CT have been applied in the functional assessment of residual pituitary adenomas. Methods: We retrospectively reviewed our series of patients submitted to 68Ga-peptides and/or 18F-FDG PET-CT for evaluating residual pituitary adenomas after primary surgery. Results: Sixteen patients underwent 68Ga-peptides and/or 18F-FDG PET/CT in the period 2012-2018 at our Institution. A total of 15 68Ga-peptides PET/CT scans and 8 18F-FDG PET/CT scans were performed. Fourteen patients had pituitary adenoma, and two pituitary carcinoma. Nine patients were affected by not-secreting (null cell) pituitary adenoma; 3 patients by Cushing disease; 3 patients by acromegaly and a single patients by prolactinoma. All patients underwent partial removal of the pituitary adenoma, as all cases invaded the cavernous sinus. Mean Ki67 was 4% (SD: 3). Positivity at 68Ga-peptides PET/CT was detected in 10 patients. Positivity at 18F-FDG PET/CT was detected in 6 patients. Six patients were submitted to both PET/CT scans: 4 showed concordant results and two were positive only at 68Ga-peptide PET/CT. Nine patients with residual tumor positive at 68Ga-peptides PET/CT were treated with long-acting somatostatin analogues (L-SSA). Progression of the residual adenoma was observed in 9 patients: 6 were positive at 68Ga-peptide PET/CT and 5 were positive at FDG PET/CT. 5 patients were on treatment with L-SSA. Mean follow-up was 37.8 months (DS:30). The only determinant of progression disease was the Ki67: in patients with progression of pituitary adenoma, mean Ki67 was 5% (SD: 3, p=0.05) and in patients with stable disease its mean value was 1.5% (SD:1.5). Conclusion: 68Ga-peptides and 18F-FDG PET/CT can be useful for functional evaluation of residual pituitary adenomas after primary surgery and in scheduling the therapeutic management. In any case, the main determinant of disease progression is represented by the Ki67 index. Unless otherwise noted, all abstracts presented at ENDO are embargoed until the date and time of presentation. For oral presentations, the abstracts are embargoed until the session begins. Abstracts presented at a news conference are embargoed until the date and time of the news conference. The Endocrine Society reserves the right to lift the embargo on specific abstracts that are selected for promotion prior to or during ENDO.

Diffuse high-grade gliomas with H3 K27M mutations carry a dismal prognosis independent of tumor location

Background

The novel entity of "diffuse midline glioma, H3 K27M-mutant" has been defined in the 2016 revision of the World Health Organization (WHO) classification of tumors of the central nervous system (CNS). Tumors of this entity arise in CNS midline structures of predominantly pediatric patients and are associated with an overall dismal prognosis. They are defined by K27M mutations in H3F3A or HIST1H3B/C, encoding for histone 3 variants H3.3 and H3.1, respectively, which are considered hallmark events driving gliomagenesis.

Methods

Here, we characterized 85 centrally reviewed diffuse gliomas on midline locations enrolled in the nationwide pediatric German HIT-HGG registry regarding tumor site, histone 3 mutational status, WHO grade, age, sex, and extent of tumor resection.

Results

We found 56 H3.3 K27M-mutant tumors (66%), 6 H3.1 K27M-mutant tumors (7%), and 23 H3-wildtype tumors (27%). H3 K27M-mutant gliomas shared an aggressive clinical course independent of their anatomic location. Multivariate regression analysis confirmed the significant impact of the H3 K27M mutation as the only independent parameter predictive of overall survival (P = 0.009). In H3 K27M-mutant tumors, neither anatomic midline location nor histopathological grading nor extent of tumor resection had an influence on survival.

Conclusion

These results substantiate the clinical significance of considering diffuse midline glioma, H3 K27M-mutant, as a distinct entity corresponding to WHO grade IV, carrying a universally fatal prognosis.

Integrated Genomic Classification of Melanocytic Tumors of the Central Nervous System Using Mutation Analysis, Copy Number Alterations, and DNA Methylation Profiling

Purpose: In the central nervous system, distinguishing primary leptomeningeal melanocytic tumors from melanoma metastases and predicting their biological behavior solely using histopathologic criteria may be challenging. We aimed to assess the diagnostic and prognostic value of integrated molecular analysis.Experimental Design: Targeted next-generation sequencing, array-based genome-wide methylation analysis, and BAP1 IHC were performed on the largest cohort of central nervous system melanocytic tumors analyzed to date, including 47 primary tumors of the central nervous system, 16 uveal melanomas, 13 cutaneous melanoma metastases, and 2 blue nevus-like melanomas. Gene mutation, DNA-methylation, and copy-number profiles were correlated with clinicopathologic features.Results: Combining mutation, copy-number, and DNA-methylation profiles clearly distinguished cutaneous melanoma metastases from other melanocytic tumors. Primary leptomeningeal melanocytic tumors, uveal melanomas, and blue nevus-like melanoma showed common DNA-methylation, copy-number alteration, and gene mutation signatures. Notably, tumors demonstrating chromosome 3 monosomy and BAP1 alterations formed a homogeneous subset within this group.Conclusions: Integrated molecular profiling aids in distinguishing primary from metastatic melanocytic tumors of the central nervous system. Primary leptomeningeal melanocytic tumors, uveal melanoma, and blue nevus-like melanoma share molecular similarity with chromosome 3 and BAP1 alterations, markers of poor prognosis. Clin Cancer Res; 24(18); 4494-504. ©2018 AACR.

Prognostic factors in brain metastases from laryngeal squamous cell carcinoma: Case report and review

Background:

Brain metastases from laryngeal squamous cell carcinoma (SCC) are rare, and there are no standardized treatments. Here we reported on a case of brain metastasis from laryngeal SCC and performed a literature review on these cases. Moreover, by plotting Kaplan–Meier curves, we carried out a survival analysis to provide an estimation of overall survival (OS) and to find possible prognostic factors.

Case Description:

A 65-year-old male was admitted to our department with a large left occipital lesion. Three years ago, the patient had undergone total laryngectomy with bilateral neck dissection with a diagnosis of a poor differentiated SCC. The occipital lesion was totally removed. A diagnosis of a brain metastasis from laryngeal SCC was made. The patient was submitted to adjuvant chemotherapy and radiation therapy. He is in good clinical conditions at 7-month follow-up with a still ongoing chemotherapy. From survival analysis, we have found that surgery and/or radiochemotherapy increase the OS of these patients compared with untreated cases. Moreover, Karnofsky performance status (KPS) score ≥70 and recursive partitioning analysis (RPA) classes I and II were associated with better OS in these patients.

Conclusion:

Brain metastases from laryngeal SCC are rare. This is the first study in which a survival analysis of these cases has been performed. Surgery and/or radio-chemotherapy increase the survival of these patients compared with untreated cases. Moreover, KPS score and RPA class affect the outcome of these patients.

Telocytes are the physiological counterpart of inflammatory fibroid polyps and PDGFRA-mutant GISTs

PDGFRA mutations in the gastrointestinal (GI) tract can cause GI stromal tumour (GIST) and inflammatory fibroid polyp (IFP). Hitherto no cell type has been identified as a physiological counterpart of the latter, while interstitial Cajal cells (ICC) are considered the precursor of the former. However, ICC hyperplasia (ICCH), which strongly supports the ICC role in GIST pathogenesis, has been identified in germline KIT-mutant settings but not in PDGFRA-mutant ones, challenging the precursor role of ICC for PDGFRA-driven GISTs. Telocytes are a recently described interstitial cell type, CD34+/PDGFRA+. Formerly considered fibroblasts, they are found in many organs, including the GI tract where they are thought to be involved in neurotransmission. Alongside IFPs and gastric GISTs, GI wall "fibrosis" has been reported in germline PDGFRA-mutants. Taking the opportunity offered by its presence in a germline PDGFRA-mutant individual, we demonstrate that this lesion is sustained by hyperplastic telocytes, constituting the PDGFRA-mutant counterpart of germline KIT mutation-associated ICCH. Moreover, our findings support a pathogenetic relationship between telocyte hyperplasia and both IFPs and PDGFRA-mutant GISTs. We propose the term "telocytoma" for defining IFP, as it conveys both the pathogenetic (neoplastic) and histotypic ("telocytary") essence of this tumour, unlike IFP, which rather evokes an inflammatory-hyperplastic lesion.

Tuberculous Arthritis of the Ankle

Tuberculosis (TB) is an infectious disease caused by the Mycobacterium tuberculosis complex (MTBC). Pulmonary TB is the most common form of presentation, but extrapulmonary tuberculosis (EPTB) contributes significantly to morbidity and mortality. Rarely, patients with EPTB develop a form of ankle or foot arthritis. The diagnosis of TB arthritis is often overlooked because of the insidious onset and the non-specific clinical symptoms. Prognosis is generally poor; early diagnosis and delivery of the most appropriate treatment is critical to avoid functional disability.

DNA methylation-based classification of central nervous system tumours

Accurate pathological diagnosis is crucial for optimal management of patients with cancer. For the approximately 100 known tumour types of the central nervous system, standardization of the diagnostic process has been shown to be particularly challenging-with substantial inter-observer variability in the histopathological diagnosis of many tumour types. Here we present a comprehensive approach for the DNA methylation-based classification of central nervous system tumours across all entities and age groups, and demonstrate its application in a routine diagnostic setting. We show that the availability of this method may have a substantial impact on diagnostic precision compared to standard methods, resulting in a change of diagnosis in up to 12% of prospective cases. For broader accessibility, we have designed a free online classifier tool, the use of which does not require any additional onsite data processing. Our results provide a blueprint for the generation of machine-learning-based tumour classifiers across other cancer entities, with the potential to fundamentally transform tumour pathology.

Clinical and immunological characteristics of the spectrum of GFAP autoimmunity: a case series of 22 patients

OBJECTIVE

To report the clinical and immunological characteristics of 22 new patients with glial fibrillar acidic protein (GFAP) autoantibodies.

METHODS

From January 2012 to March 2017, we recruited 451 patients with suspected neurological autoimmune disease at the Catholic University of Rome. Patients' serum and cerebrospinal fluid (CSF) samples were tested for neural autoantibodies by immunohistochemistry on mouse and rat brain sections, by cell-based assays (CBA) and immunoblot. GFAP autoantibodies were detected by immunohistochemistry and their specificity confirmed by CBA using cells expressing human GFAPα and GFAPδ proteins, by immunoblot and immunohistochemistry on GFAP-/- mouse brain sections.

RESULTS

Serum and/or CSF IgG of 22/451 (5%) patients bound to human GFAP, of which 22/22 bound to GFAPα, 14/22 to both GFAPα and GFAPδ and none to the GFAPδ isoform only. The neurological presentation was: meningoencephalomyelitis or encephalitis in 10, movement disorder (choreoathetosis or myoclonus) in 3, anti-epileptic drugs (AED)-resistant epilepsy in 3, cerebellar ataxia in 3, myelitis in 2, optic neuritis in 1 patient. Coexisting neural autoantibodies were detected in five patients. Six patients had other autoimmune diseases. Tumours were found in 3/22 patients (breast carcinoma, 1; ovarian carcinoma, 1; thymoma, 1). Nineteen patients were treated with immunotherapy and 16 patients (84%) improved. Histopathology analysis of the leptomeningeal biopsy specimen from one patient revealed a mononuclear infiltrate with macrophages and CD8+ T cells.

CONCLUSIONS

GFAP autoimmunity is not rare. The clinical spectrum encompasses meningoencephalitis, myelitis, movement disorders, epilepsy and cerebellar ataxia. Coexisting neurological and systemic autoimmunity are relatively common. Immunotherapy is beneficial in most cases.