Giant Cell Research Articles

Retrospective Analysis of Specimen Quality in Temporal Artery Biopsies for Giant Cell Arteritis and Disease Association in North Midlands, England.

Background Temporal artery biopsy (TAB) is the recommended index diagnostic method for giant cell arteritis (GCA). Per the British Society for Rheumatology (BSR) guidelines, we assessed our procedural performance. Additionally, we evaluated the occurrence of GCA diagnosis in immunosuppressed patients and other comorbidities. Methods Following the audit registration, a retrospective analysis of prospectively collected data was conducted from 2017 to 2022 at a large university hospital in North Midlands, England. Data on demographics and comorbidities were gathered. The study's primary outcome was adherence to BSR guidelines and our service provisions. Secondary outcomes included examining the relationship between biopsy-confirmed GCA and other comorbidities. Statistical analysis was carried out using SPSS version 29 (IBM Corporation, Armonk, New York, United States of America). Two-sample t-test and Chi-square/Fisher exact test were used for continuous and categorical variables, respectively. Holm-Bonferroni method was incorporated to adjust for multiple comparisons. Results A total of 156 patients who underwent temporal artery biopsy (TAB) were included in the study, with a male-to-female ratio of 0.44:1. The median age was 73. Among the patients, 19% were smokers. The procedures were performed by either a vascular surgeon (119, 76%) or by an ophthalmologist (37, 24%). Two-thirds of the patients underwent TAB within seven days of referral. In 73, 47% of cases, the post-fixation biopsy sample size exceeded 10 mm. Positive biopsy results were found in 45 patients (29%). GCA was confirmed in 39% of patients with polymyalgia rheumatica (PMR), 24% with diabetics, 20% with hypothyroidism, 29% with hypertension, 32% with hyperlipidaemia,and 26% with other inflammatory diseases. However, the p-value was below the statistically significant threshold. The biopsy outcome was also not dependent on the speciality, time from referral to biopsy, nor on the length of the post-fixation specimen. Conclusions Temporal artery biopsy remains a valuable and crucial diagnostic tool in challenging equivocal cases of giant cell arteritis (GCA), although it is limited by its sensitivity, but there is also room for improvement. There is still uncertainty regarding the relationship between biopsy positivity, post-fixation sample size, and the interval between referral and procedure. Additionally, the speciality of the clinician performing the biopsy does not appear to significantly influence the likelihood of a positive result. We still do not fully understand why this is, but the association of the GCA with other comorbidities was unpredictably insignificant.

Predictive biomarkers of response to tocilizumab in giant cell arteritis (GCA): correlations with imaging activity.

In the recent EULAR recommendations, ultrasound examination is now recommended as a first-line imaging test in all patients with suspected giant cell arteritis (GCA) and the axillary arteries should be included in the standard exam. As an alternative to ultrasound evaluation, cranial and extracranial arteries can be examined using FDG-PET or MRI. The aim of our study was to observe in a retrospective case series whether there is a correlation between biomarkers and imaging activity in a population of patients followed in real life with GCA treated with prednisone (PDN) and tocilizumab (TCZ). We retrospectively enrolled 68 patients with newly diagnosed GCA between January 2020 and September 2021, followed in real life, who were examined at the Rheumatology Unit of the San Giovanni di Dio Hospital, Florence, Italy. Patients were evaluated at T0-T3-T6-T12-T18-T24 for the following blood tests: ESR, CRP, fibrinogen, platelet count, serum amyloid A (SAA), IL-6, and circulating calprotectin (MRP). Ultrasound examination of the temporal arteries and axillary arteries was assessed at T0 within 7days of starting treatment with high-dose glucocorticoids and subsequently at T3-T6-T12-T18-T24. A scale from 0 to 3 with semi-quantitative tools (SUV max) was assessed at T0-T12-T24. The evaluation of the correlation coefficient between laboratory and imaging variables has shown that SAA and MRP have the most powerful correlation with the PET score (0.523 and 0.64), and MRP also has an excellent correlation coefficient with the Halo score (0.658). The evaluation of the ROC curves shows for a PET score 3 and SAA values higher than 26mg/L, sensitivity of 81.5% and specificity of 84.1%, and for a PET score 3 and MRP values higher than 2.3 mcg/mL, sensitivity of 100% and specificity of 76.8%. In this study, we demonstrated that SAA and MRP can be useful as promising tools to detect GCA activity. The study demonstrates a good correlation between the two biomarkers and the imaging activity evaluated by the Halo and PET scores.

Update on Giant Cell Arteritis: Essential Information for Ophthalmologists

Update on Giant Cell Arteritis: Essential Information for Ophthalmologists

Determinants of cough-related quality of life in interstitial lung diseases

BackgroundInterstitial lung diseases (ILD) include a wide range of diseases impacting lung parenchyma and leading to fibrosis and architectural distortion. Chronic cough and dyspnea are common symptoms which affect the quality of life (QoL) in ILD patients. The mechanisms of cough in ILD patients are still unknown. The aim of this study was to prospectively investigate histological, radiological, and physiological determinants of cough-related QoL in ILD patients who underwent transbronchial lung cryobiopsy (TBLC).MethodsAll patients (n = 111) filled in The Leicester Cough Questionnaire (LCQ) and The St George’s Respiratory Questionnaire (SGRQ). They underwent lung function tests, forced vital capacity (FVC), forced vital expiratory volume in 1 s (FEV1), diffusion capacity to carbon monoxide (DLCO), high-resolution computed tomography (HRCT), and blood samples before diagnostic TBLC. Two experienced radiologists assessed the extents of following HRCT patterns: ground-glass opacities (GGO), honeycombing, reticulation, traction bronchiectasis, and emphysema. Histology of TBLC were re-analyzed by two experienced pulmonary pathologists and the presence of fibroblast foci, fibrosis, giant cells, granulomas, and honeycombing were recorded.ResultsIn the median multivariate regression analysis, BMI (-0.19; 95% CI -0.37- -0.014; p 0.035), GGO (-0.38; 95% CI -0.61- -0.15; p 0.001), granulomas (-3.21; 95% CI -6.12- -0.30; p 0.031), and current smoking (2.49; 95% CI 0.12–4.86; p 0.040) showed independent associations with LCQ total score. BMI (1.3; 95% CI 0.20–2.42; p 0.021) and DLCO (-0.51; 95% CI -0.85 - -0.16; p 0.004) showed independent association with SGRQ total score.ConclusionDeterminants of cough-related QoL in ILD patients are multifactorial including physiological, radiological and histological parameters.

Denosumab in irresectable giant cell tumour of the cervical spine

Denosumab in irresectable giant cell tumour of the cervical spine

Diagnostic challenge of the brown tumors in developing country: A case series

Introduction and importanceBrown tumors are non-neoplastic reactive tissue with osteoclasts multinucleated giant cells, and vascular and proliferative fibrous tissue. Hemorrhage results in significant bone resorption caused by hyperparathyroidism. This study provides information about the diagnosis challenge for brown tumor cases. Case descriptionWe report four cases that experience pathological fractures with moderate pain, multiple lytic lesions, severe hypercalcemia, increased ALP (Alkaline Phosphatase), and PTH (Parathyroid Hormone). Abnormal parathyroid mass was found in ultrasound. A bone scan described increasing radio uptake in various bones, a whole body scan, or parathyroid scintigraphy with 99mTc-MIBI. Eventually, in all cases, the diagnosis of the brown tumor was confirmed through histopathological examination, which showed multiple nucleated giant cells with a deposit of hemosiderin pathognomonic for the brown tumor, and the diagnosis of primary hyperparathyroidism (PHPT) was confirmed in all cases. Clinical discussionThese cases show that initial misdiagnosis of brown tumors as other bone tumors. A definitive diagnosis of brown tumors requires more than just histological confirmation. A comprehensive evaluation encompassing laboratory tests, imaging studies, clinical symptoms, and a multidisciplinary orthopedic-oncology board discussion is essential. Observations show that treating hyperparathyroidism alleviates the osteolytic lesions caused by brown tumors, despite the lack of clinical guidelines. ConclusionBased on a review of the literature and our clinical experience, we recommend screening serum calcium, phosphorus, and PTH levels in patients presenting with multiple lesions and widespread bone pain. This screening aims to rule out multiple bone lesions caused by PHPT.

Instant rerouting of photosynthetic electron transport to O2 reduction after the plasma membrane excitation of Chara in the presence of methyl viologen

—Action potential (AP) of excitable plant cells is an important signaling event that can differentially alter physicochemical and physiological processes in various parts of the same cell. In giant cells of characean algae, the AP propagation has minor effect on photosynthetic electron transport in areas with high activity of plasmalemmal H+-pump but inhibits linear electron flow in regions featuring high passive H+/OH− conductance of the plasma membrane (PM). Uneven spatial distributions of local periplasmic and cytoplasmic pH facilitate the operation of distinct (CO2-dependent and O2-mediated) pathways of photoinduced electron flow, which presumably accounts for differential influence of AP on photosynthesis. The excitation of Chara australis cell in the presence of methyl viologen (MV), a redox mediator with the prooxidant action, provides a convenient model system to clarify the influence of voltage-dependent ion fluxes across PM on photosynthetic activity of chloroplasts. This study shows that permeation of MV to their target sites in chloroplasts is restricted by PM in resting cells, but MV easily passes through ionic channels opened during the PM depolarization. This gated permeation of MV gives rise to strong non-photochemical quenching, decrease in the effective quantum yield of linear electron flow, apparent O2 uptake, and, finally, the enhanced ROS production, as detected by the fluorescent probe dichlorofluorescein. Taken together, the results indicate that the AP generation in the presence of MV acts as trigger for instant redirection of photosynthetic linear electron flow from CO2-dependent route to the path of O2 reduction with the eventual formation of H2O2 as a dominant and most stable ROS form.

Predictors of Permanent Vision Loss in Giant Cell Arteritis

ABSTRACT To report on the occurrence and characteristics of eye manifestations and determine the predictors of permanent vision loss (PVL) in patients with giant cell arteritis. Case-control study. Retrospective cohort study of 258 patients diagnosed with giant cell arteritis (GCA) over a 20- year period at a single institution. Eighty nine of 258 patients (34.5%) with GCA had vision symptoms and 56 (21.7%) developed PVL. Acute loss of vision with no preceding ocular symptoms occurred in 28.5%; for those with symptoms, median time to vision loss was 4.5 days. Bilateral clinical eye involvement was present in 38%, mostly anterior ischemic optic neuropathy (AION), rarely vascular occlusions. Vision loss was severe with acuity of count fingers or less or mean deficit −20 decibels or less in at least one eye in 80% of patients with PVL. Following initiation of GC treatment, 23% of patients continued to have further vision loss and only 5% showed improvement. We found predictors of PVL by multivariate analysis to be increased age (OR 1.05, p0.040), jaw claudication (OR 2.29, p = .040), diplopia (OR 2.74, p = .039), increased platelets (OR 2.98, p = .020) and lower CRP (OR 0.63, p = .004). We found there is a 27.3% decrease in the odds of having PVL when CRP value is doubled, keeping all other variables fixed. Permanent vision loss was 3.07 times more likely in the absence of polymyalgia rheumatica and 4.25 times more likely in patients without headaches. Ocular involvement in GCA is common, usually severe with little chance of recovery. Detailed analysis of visual acuity and visual field loss in our PVL cohort adds valuable data to the literature which lacks this information. Older patients with jaw claudication, diplopia, and increased platelets are at higher risk for permanent vision loss, especially when PMR and headache are absent and acute phase reactants lower.

Erdheim-chester disease with bilateral proptosis, coated aorta and hairy kidney

Erdheim-Chester disease (ECD) is a rare histiocytic disorder with a spectrum of clinical manifestations, ranging from asymptomatic single-organ involvement to multisystem disease. We present a classic case of ECD with detailed radiographic and histopathologic findings. A 63-year-old Thai female with a history of triple vessel disease post-PCI presented with bilateral proptosis and blurred vision for one year. On admission, she exhibited marked proptosis epiblepharon, lagophthalmos, conjunctival injection, chemosis, limited extraocular movement and cranial nerve II palsy. Imaging showed increased bilateral retro-orbital infiltrative lesions, osteosclerotic changes, and soft tissue thickening along the great vessels and retroperitoneum. A retro-orbital soft tissue biopsy showed foamy histiocytic proliferation with Touton giant cells. EDC was confirmed by next-generation sequencing revealing a BRAF V600E mutation. This patient received pegylated interferon-alpha. At 1-year follow-up visit, the disease remained stable. In this report, we present a classic case of EDC. The rarity of this disease makes it challenging to diagnose. The typical presentation characteristics raise awareness for the diagnosis of EDC, which is based on features such as osteosclerotic lesions in the long bones, soft tissue infiltration in medium to large vessels (coated aorta) and the bilateral pelvicalyceal systems (hairy kidney). These findings were confirmed through tissue pathology and molecular diagnostics.

Non-infectious hypertrophic pachymeningitis associated with orbital inflammatory disease: a pooled analysis.

To describe four cases of non-infectious hypertrophic pachymeningitis (HP)-associated with orbital inflammatory disease (OID). This study summarises the clinico-radiological features, outcomes, and management of HP-associated OID. Retrospective case-series of patients with radiological evidence of HP and OID. Comprehensive literature review of all published English-language non-infectious causes of HP-associated OID. Reference lists were screened for inclusion of relevant articles. Thirty-seven cases of HP-associated OID (Mean age: 49.2 ± 17.4 years old; Male: 15) were identified, including four cases from our institution. Aetiologies included ANCA-associated vasculitis (12/37), non-specific/idiopathic (11/37), IgG4/multifocal fibrosclerosis (11/37), neurosarcoidosis (1/37), inflammatory myofibroblastic tumour (1/37), and giant cell arteritis (1/37). Orbital pain, headache, visual deterioration, and cranial nerve palsies were common clinical presentations. Both "focal" and "diffuse" HP were observed, with the most common sign of orbital involvement being an inflammatory orbital mass, typically with orbital apex involvement. Orbital myositis and dacryoadenitis were less common. The cavernous sinus was the most common site of extra-orbital inflammation. There was no single differentiating specific radiological feature between non-specific and specific forms of HP-associated OID. The clinico-radiological manifestations of HP-associated OID differ from those described in isolated HP or OID. There is no single specific radiological marker differentiating non-specific/idiopathic disease from secondary causes; however, the co-existence of HP in OID should prompt suspicion of an underlying cause. The disease may be refractory or resistant to initial treatment, although guidelines surrounding its management and the long-term prognosis remain to be determined.

Beyond dermatomes disseminated Herpes zoster in the immunocompetent: two rare cases

Herpes zoster is typically a localized reactivation of the varicella-zoster virus (VZV) that occurs in individuals following a primary varicella infection (chickenpox). Disseminated herpes zoster, characterized by widespread vesicular lesions beyond the primary dermatome, is uncommon and usually associated with immunocompromised states. Till date only 25 immunocompetent patients with disseminated HZ have been reported in literature. We report two such cases of disseminated HZ in immunocompetent individuals. The 1st patient is a 53-year-old woman with painful, itchy multiple grouped erythematous papules, vesicles, and bullae over right T8-T9 dermatome and multiple papules, crusted papules, and vesicles over face associated with fever and fatigue. The 2nd patient is an 8-year-old boy with multiple grouped clear vesicles and bullae with erythematous base involving the left S1-S5 dermatome. Multiple discrete erythematous papules and vesicles (active and crusted) were noted over trunk, right forearm, left arm, bilateral thigh and left mandibular area. Routine laboratory investigations were within normal limits. Tzanck smears were done, and multinucleated giant cells were seen in both cases. They were treated with antivirals and showed improvement. We have reported these two cases of disseminated HZ due to their occurrence in immunocompetent patients, which is a very rare phenomenon.

Giant cell arteritis as a cause of extracranial internal carotid artery aneurysm: a case report

BackgroundThis report presents the management of patient with extracranial internal carotid artery pseudoaneurysm due to giant cell arteritis.Case presentationLeft internal carotid artery pseudoaneurysm was diagnosed in a 57-year-old Ukrainian woman, which became a direct indication for surgical treatment involving aneurysm resection and internal carotid artery reimplantation. The used reconstruction technique with oblique cutting of internal carotid artery, aneurysm resection, ellipse-form anastomosis formation, and distal intima fixation prevents the dissection, restenosis, and aneurysm of anastomosis in the long-term postoperative period. Histopathological examination revealed the giant cell arteritis of the internal carotid artery.ConclusionThis case emphasizes the importance of open surgical treatment of extracranial carotid artery aneurysms, which allows to perform optimal carotid artery reconstruction and also define the rare etiology of disease.

Pleomorphic Liposarcoma Cytologically Detected in Hemosiderotic Pleural Effusion: Pitfalls Mitigated by Cytologic Clues and Cellblock Immunocytochemistry.

Sarcomatous serous effusions are uncommon and diagnostically challenging. Dedifferentiated and pleomorphic liposarcomas are rare tumors in pleural effusions revealing highly pleomorphic tumor cells mimicking carcinoma, mesothelioma, melanoma, and other sarcomas. Hematothoracic effusions further complicate the cytologic diagnosis. Correct cytologic recognition is important. We report pleomorphic liposarcoma cytologically detected in effusion fluid in a 56-year-old man who presented with a massive unilateral pleural effusion. ThinPrep showed hemorrhagic effusion fluid characterized by lysed red blood cells, foamy macrophages, and siderophages intermixed with highly pleomorphic predominantly naked mononuclear and giant nuclei. The aggregated siderophages and vacuolated macrophages could be mistaken for tumor cells, whereas the bare nuclei may be missed as nonspecific degenerate changes. Cellblock sections showed highly pleomorphic mononuclear and multinucleated giant tumor cells with diagnostic lipoblasts, intermixed with foamy macrophages and siderophages. Cellblock immunocytochemistry showed staining for vimentin and S-100 protein in the tumor cells. Other lineage-specific immunomarkers were negative. CD68 and calretinin revealed frequent background macrophages and scarce mesothelial cells. The tumor cells were negative for MDM2 and CDK4. The entertained cytopathologic diagnosis was pleomorphic liposarcoma. Core needle biopsy was procured from the mass. The histopathologic features and immunoprofile of the tissue specimen matched the cytopathologic and immunocytochemical findings confirming the cytologic diagnosis of pleomorphic liposarcoma. Pleomorphic liposarcoma is an unexpected cytologically challenging finding in effusions, particularly when compounded by pitfalls introduced by hemosiderotic fluid. Attention to certain cytologic clues mitigate pitfalls. Cellblock is a valuable diagnostic tool when integrated with relevant negative and positive immunocytochemical markers.

Primary immunodeficiency-related genes and varicella-zoster virus reactivation syndrome: a Mendelian randomization study.

Currently, evidence regarding the causal relationship between primary immunodeficiency-related genes and varicella-zoster virus reactivation syndrome is limited and inconsistent. Therefore, this study employs Mendelian randomization (MR) methodology to investigate the causal relationship between the two. This study selected 110 single-nucleotide polymorphisms (SNPs) of primary immunodeficiency-related genes as instrumental variables (IVs). Genetic associations of primary immunodeficiency-related genes were derived from recent genome-wide association studies (GWAS) data on human plasma protein levels and circulating immune cells. Data on genes associated with varicella-zoster virus reactivation syndrome were obtained from the GWAS Catalog and FINNGEN database, primarily analyzed using inverse variance weighting (IVW) and sensitivity analysis. Through MR analysis, we identified 9 primary immunodeficiency-related genes causally associated with herpes zoster and its subsequent neuralgia; determined causal associations of 20 primary immunodeficiency-related genes with three vascular lesions (stroke, cerebral aneurysm, giant cell arteritis); revealed causal associations of 10 primary immunodeficiency-related genes with two ocular diseases (retinopathy, keratitis); additionally, three primary immunodeficiency-related genes each were associated with encephalitis, cranial nerve palsy, and gastrointestinal infections. This study discovers a certain association between primary immunodeficiency-related genes and varicella-zoster virus reactivation syndrome, yet further investigations are warranted to explore the specific mechanisms underlying these connections.

Sixth cranial nerve palsy in giant cell arteritis: A systematic review

Objectives: This study aimed to review and describe isolated sixth cranial nerve or abducens nerve palsy that may present with subtle ophthalmoplegia in patients with giant cell arteritis (GCA). Materials and methods: In this systematic review following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) Extension for Scoping Reviews, MEDLINE and EMBASE were searched for all peer-reviewed articles using the keywords “cranial nerve six,” “abducens nerve,” and “giant cell arteritis” from their inception to December 22, 2022. Results: Twenty-five articles, including seven observational studies and 18 cases, were included. While the incidence and prevalence of sixth nerve palsy in GCA were variable, up to 48% of diplopia in GCA were attributed to the sixth cranial nerve palsy, according to the observational studies included. While 88.2% had a resolution of symptoms with 40-50 mg/day of prednisone-equivalent corticosteroids, it took a median of 24.5 days until the resolution of symptoms from the initiation of treatment. Conclusion: This review summarizes the current understanding of the characteristics of sixth nerve palsy in GCA. While most patients may have reversible clinical courses, a few can suffer from persistent ophthalmoplegia, which is a potentially missed yet crucial clinical finding in GCA. Increased awareness of the sixth nerve palsy in GCA is crucial.

Stroke pattern in giant-cell arteritis mostly involves watershed areas

ContextStroke related to giant cell arteritis (GCA) is rare and is associated with a poor outcome. One of the putative ischemic mechanisms is narrowing of the arterial lumen due to wall infiltration by inflammation and intimal proliferation, leading to reduced distal blood flow. It was hypothesized that GCA-related stroke could predominate in watershed areas (WA). MethodsLiterature review including all cases of GCA-related stroke with brain images. ResultsAmong 75 cases of GCA-related stroke, the anterior and posterior territories were involved in 48 % and 62.6 %, respectively. Up to 88.9 % of cases of anterior stroke probably involved WA. WA lesions in the posterior territories were as follows: uni/bilateral middle cerebellar peduncle (MCP) lesions in 25.5 %, and with less confidence, non-wedge-shaped cerebellar lesions in 46.8 %, or combined lesions in 61.7 %. Stenosis or occlusion of the afferent artery was almost always observed. A few lesions were not easily explained by low flow. DiscussionDespite the limitations of arterial territory allocation especially in the posterior circulation, ischemic lesions mainly occurred in WA. MCP lesions, which were typically WA, were highly characteristic of GCA. Low flow downstream focal stenosis was the main, but not the unique, ischemic mechanism of GCA stroke.

Low incidence of late-onset giant cell arteritis during the first year in patients with polymyalgia rheumatica-a repeated imaging study.

The objective was to investigate the incidence of late-onset giant cell arteritis (GCA) within the first year in patients diagnosed with polymyalgia rheumatica (PMR). In this prospective study, treatment-naïve individuals with a new clinical diagnosis of PMR and without GCA symptoms underwent baseline assessments, including vascular ultrasonography and 2-[18F]fluoro-2-deoxy-D-glucose positron emission tomography computed tomography (FDG-PET/CT). To prevent biased inclusion, rapid referral clinics were established for all patients suspected of PMR. Additionally, the patients underwent GCA monitoring during clinical visits at weeks 8 and 10, which involved vascular ultrasonography and FDG-PET/CT scans. After one year, a follow-up visit was performed to confirm the PMR diagnosis and perform vascular ultrasonography. A final PMR diagnosis was assigned to 62 patients, excluding 2 patients with concurrent subclinical GCA and PMR at baseline, corresponding to a baseline prevalence of subclinical GCA of 3%. During the one-year follow-up, two PMR patients developed late-onset GCA corresponding to an incidence rate of 32 per 1000 person-years. One patient developed GCA 14 weeks after the PMR diagnosis, exhibiting cranial symptoms and positive vascular ultrasonography. The other patient presented with subclinical large vessel GCA at the one-year visit detected with vascular ultrasonography and confirmed by FDG-PET/CT. This study is the first to demonstrate a low incidence rate of late-onset GCA in PMR patients within the first year, employing repeated imaging to exclude GCA at baseline and diagnose GCA during follow-up. Additionally, it provides evidence of a low prevalence of subclinical GCA across the entire PMR population. ClinicalTrials.Gov, NCT04519580.

Chondroid Synoviocytic Neoplasm: A Clinicopathologic, Immunohistochemical, and Molecular Genetic Study of a Distinctive Tumor of Synoviocytes

Tumors resembling tenosynovial giant cell tumor (TGCT) but additionally forming chondroid matrix are rare and most often involve the temporomandibular joint (TMJ). We studied 21 tumors consisting of synoviocytes (large, eosinophilic mononuclear cells containing hemosiderin) and chondroid matrix to better understand these unusual neoplasms. The tumors occurred in 10 males and 11 females, in the age group of 31 to 80 years (median, 50 years) and involved the TMJ region (16), extremities (4), and spine (1). As in conventional TGCT, all were composed of synoviocytes, small histiocytes, foamy macrophages, siderophages, and osteoclast-like giant cells in variably hyalinized background. Expansile nodules of large, moderately atypical synoviocytes were present, in addition to “chondroblastoma-like,” “chondroma-like,” or “phosphaturic mesenchymal tumor-like” calcified matrix. The synoviocytes expressed clusterin (17/19) and less often desmin (3/15). The tumors were frequently CSF1 positive by chromogenic in situ hybridization (8/13) but at best weakly positive for CSF1 by immunohistochemistry (0/3). Background small histiocytes were CD163 positive (12/12). All were FGF23 negative (0/10). Cells within lacunae showed a synoviocytic phenotype (clusterin positive; S100 protein and ERG negative). RNA-Seq was successful in 13 cases; fusions were present in 7 tumors, including FN1::TEK (5 cases); FN1::PRG4 (2 cases); and MALAT1::FN1, PDGFRA::USP35, and TIMP3::ZCCHC7 (1 case each). Three tumors contained more than 1 fusion (FN1::PRG4 with TIMP3::ZCCHC7, FN1::TEK with FN1::PRG4, and FN1::TEK with MALAT1::FN1). Clinical follow-up (17 patients; median follow-up duration 38 months; range 4-173 months) showed 13 (76%) to be alive without evidence of disease and 4 (24%) to be alive with persistent/recurrent local disease. No metastases or deaths from disease were observed. We conclude that these unusual tumors represent a distinct category of synoviocytic neoplasia, which we term “chondroid synoviocytic neoplasm,” rather than simply ordinary TGCT with cartilage. Despite potentially worrisome morphologic features, they appear to behave in at most a locally aggressive fashion.

Interpreting Histopathology Reports of Temporal Artery Biopsies Positive for Giant Cell Arteritis (GCA): A Single-Center Retrospective Study.

The gold standard for diagnosing giant cell arteritis (GCA) is temporal artery biopsy (TAB). However, specific histopathologic findings on biopsy reports are rarely considered in the context of the patient's clinical presentation. The purpose of this study was to analyze the correlation of specific biopsy findings with the clinical presentation of patients with GCA. Retrospective chart review of patients with a clinical and histopathologic diagnosis of GCA at a single tertiary care neuro-ophthalmology practice from January 2014 to September 2023. Histopathologic findings on TAB were recorded for each patient, along with clinical history, examination, and treatment. Continuous variables were reported as mean values with standard deviations (SD), while categorical variables were described as percentages. Correlation coefficients with P-values were used to evaluate the relationship between biopsy findings and clinical data. A total of 53 patients were included. TAB specimens ranged in length from 0.6 to 3.4 cm, with a statistically significant correlation coefficient between specimen length and total number of positive findings on the biopsy report. A positive correlation coefficient that approached statistical significance was found between the presence of lymphocytes in the biopsy and permanent vision loss (R = 0.253, P-value 0.054), which occurred in 27 patients. Patients were treated with steroids prebiopsy for an average of 9 days; there was no statistically significant correlation between the duration of steroid treatment and the presence of specific histopathologic findings other than involvement of the intima. The results of this study demonstrate that (1) longer temporal artery biopsy specimens are significantly correlated with a higher number of findings on biopsy reports; (2) the presence of arterial stenosis, eosinophils, and lymphocytes correlated with permanent vision loss or degree of vision loss; and (3) the duration of steroid treatment had a significant inverse correlation with intimal involvement but did not affect other histopathologic findings seen with GCA. This retrospective observational study provides clinicians with an approach to understanding the nuances of the histopathologic findings on their patient's TAB report.

Large vessel vasculitis is a risk factor for relapse only in giant cell arteritis patients without polymyalgia rheumatica.

To evaluate differences in presentation and outcome of giant cell arteritis (GCA) patients with and without large vessel vasculitis (LVV) and according to the extent and severity of LVV. Consecutive patients diagnosed with GCA between 2003 and 2020 who have had FDG PET imaging at diagnosis ≤3 days after initiation of glucocorticoids and followed for ≥12 months at the University Hospitals Leuven (Belgium), were included retrospectively. PET scans were visually scored (0-3) in 7 vascular areas and a total vascular score (TVS) was calculated. LVV was defined as FDG uptake ≥2 in any large vessel. We included 238 GCA patients, of which 169 (71%) had LVV. LVV patients were younger (69 vs 74 years, p< 0.001) and more frequently female (72% vs 49%, p= 0.001). In patients without PMR symptoms, the presence of LVV was associated with relapse (aOR 3.05 [95%CI 1.32-7.43], p= 0.011) and with a lower probability of stopping glucocorticoids (aHR 0.59 [95%CI 0.37-0.94], p= 0.025). However, in those with PMR symptoms, there was no difference in relapse risk (aOR 1.20 [95%CI 0.53-2.66], p= 0.657) and in the probability of stopping glucocorticoids (aHR 1.25 [95%CI 0.75-2.09], p= 0.394) between patients with and without LVV. A higher TVS was associated with an increased risk of relapse (aOR 1.09 [95%CI 1.04-1.15], p= 0.001] in patients without PMR symptoms, but not in those with PMR symptoms (aOR 1.01 [95%CI 0.96-1.07], p= 0.693). LVV is a risk factor for relapse in GCA patients without PMR symptoms with a higher relapse risk in those with higher TVS.