Orbital Tumors Research Articles

Orbital ameloblastoma: research and challenges of a rare benign tumor

Abstract There are numerous types of orbital tumors, among which orbital ameloblastoma is a rare metastatic benign tumor that often originates in the jaw and later metastasizes to the orbit. The mystery of it lies in that, although it is classified as a benign tumor, it exhibits high recurrence and malignant potential with high invasiveness, posing a serious threat to ocular health and the quality of life of patients. The prognosis of orbital ameloblastoma is relatively poor, but there is still hope. With aggressive treatment and close follow-up observation, patients may still have the possibility of achieving a longer survival period and a better quality of life. The global incidence of ameloblastoma is 0.92 cases per million people per year. According to world literature reports, there are 32 cases of maxillary bone metastasis to the orbit and 4 cases of mandibular bone metastasis to the orbit. With more and more cases and related research being reported, it is necessary to comprehensively review the etiology, clinical manifestations, diagnosis, treatment, and prognosis of orbital ameloblastoma, in order to enhance ophthalmologists' understanding and diagnostic and treatment skills of this disease, and ultimately improve patients' prognosis and quality of life.

Cavernous Hemangioma of the Orbit: A Case Report

Cavernous hemangiomas (CH) are the most common primary vascular tumors in adults, often located within the muscle cone of the orbit. These benign tumors typically present with progressive exophthalmos and visual disturbances. This case report details the presentation, diagnosis, and management of an orbital cavernous hemangioma (OCH) in a 29-year-old male with a 4-year history of non-pulsatile, irreducible exophthalmos and gradual vision loss. Imaging, including contrast-enhanced CT, confirmed the diagnosis, and surgical excision was performed using a left hemi-coronal approach. Postoperatively, the patient had an uneventful recovery, and histopathology confirmed the mass as a cavernous hemangioma. OCHs, though rare, are the most common benign orbital tumors, and surgical removal remains the treatment of choice, particularly when the tumor causes functional or aesthetic concerns. Conservative management may be considered for small, asymptomatic lesions. The prognosis is generally excellent following complete excision, with a low recurrence rate and significant improvement in both cosmetic and functional outcomes. Early diagnosis through imaging and careful surgical planning is critical for optimal results.

Development of paranasal sinus surgery in Austria and Switzerland: past, present, and future

Thanks to our predecessors and technical progress, we can nowadays offer our patients a safe and modern paranasal sinus surgery. This article provides an overview of the historical development of paranasal sinus surgery in Austria and Switzerland and to shed light on the dynamic progress of this discipline in an international context. Paranasal sinus surgery has undergone significant change in recent decades, driven by rapid technological advances that have significantly improved surgical procedures and operative outcomes. While indications were originally limited to treatment of inflammatory diseases, today, endoscopic procedures cover interventions in the area of the anterior skull base, the orbit and sinonasal tumors. The concept of functional endoscopic sinus surgery (FESS) may seem simple, but the anatomic variability, especially in the area of the frontal sinus, as well as the wide spectrum and severity of diseases can be achallenge. Therefore, paranasal sinus surgery should not be acasual operation and should only be performed by well-trained surgeons to prevent disease recurrence as well as medical and economic follow-up costs. Standardized surgical training for aspiring paranasal sinus and skull base surgeons is critical. Preoperative planning through systematic analysis of CT images is an essential factor to achieve optimal results and to avoid intraoperative complications. The pathophysiological understanding of sinonasal disease and the recent developments of new drug therapies such as monoclonal antibodies also enable excellent results in the small subgroup of patients who do not benefit from acombination of surgical rehabilitation and long-term drug therapy. The dynamic development of endoscopic paranasal sinus surgery in recent decades shows the potential of the field for the coming decades.

Orbital tumors: the relationship of histopathological examination results and clinical characteristics: A literature review

Orbital tumors, which can be neoplastic or non-neoplastic, vary in their clinical impact, ranging from cosmetic concerns to severe complications like vision loss or death in metastatic cases. These tumors are classified based on their cellular origin, including hematolymphoid, vascular, neurogenic, and others, to aid in diagnosis, prognosis, and treatment. Clinically, orbital tumors present with symptoms such as proptosis, decreased visual acuity, diplopia, pain, and inflammation, which are key diagnostic indicators. Early detection through imaging techniques like MRI and CT scans, along with histopathological examination, is crucial for effective management and preserving vision. Globally, benign orbital tumors are more common than malignant ones, with idiopathic orbital inflammation being the most frequent benign tumor. However, the prevalence and characteristics of orbital tumors are underreported in regions like Indonesia, indicating a need for better regional awareness. Histopathological examination is the gold standard for diagnosis, and its integration with clinical evaluation improves tumor identification and management. The review emphasizes the need for further studies to explore the relationship between clinical features and histopathology, which could improve early detection, diagnostic accuracy, and treatment strategies for orbital tumors.

Primary Orbital Melanoma: A Case Study Highlighting the Critical Importance of Timely Diagnosis and Treatment

Primary orbital melanoma (POM) is a rare malignant tumor arising from the deep pigmented layer of the eye, potentially leading to tumor extension and metastases, particularly to the liver. Although there are fewer than 100 documented cases, diagnosis is often delayed, with an uncoded management approach and generally unfavorable prognosis. We present the case of a 57-year-old patient with no significant medical history who developed a pigmented lesion at the inner canthus of the right eye. An excision in 2023 revealed a nodular melanoma, but the patient was already lost to follow-up before the final diagnosis was obtained. In 2024, he presented for exophthalmos with signs of significant tumor extension, necessitating radical treatment including right exenteration, ipsilateral lymphadenectomy, and radio-chemotherapy. Orbital melanomas, which represent about 7% of melanomas, manifest as painless tumors and can be better assessed by MRI. Differential diagnosis includes choroidal angiomas and metastatic tumors. Treatment requires a radical surgical approach, while chemotherapy is often ineffective. Mortality is primarily due to hepatic metastases. At six months post-operation, the outcome was favorable, and the patient received an ocular prosthesis.

Impact of Race on the Outcomes of Retinoblastoma Treated With Primary Enucleation: A Global Study of 1426 Patients.

To evaluate the clinical presentation, pathological features and outcomes of retinoblastoma based on the race of origin in a global cohort of patients. Retrospective collaborative study of 1426 patients who underwent primary enucleation for retinoblastoma. Patients were grouped into Caucasians (n = 231, 16%), Asians (n = 841, 59%), Hispanics (n = 226, 16%), Arabs (n = 96, 7%) and Others (Africans, African Americans, Indigenous Australians; n = 32, 2%) cohorts. On histopathology, massive choroidal invasion was higher in Asians (30%) and Hispanics (26%) than Caucasians (15%, p < 0.001). Post-laminar optic nerve invasion was higher in Asians (28%), Hispanics (20%) and Others (9%) than Caucasians (11%, p < 0.001). At a mean follow-up of 41 months (median, 35 months; range, < 1-149 months), tumour recurrence and metastasis-related death was higher in Hispanics (9% and 12%, respectively), Asians (4% and 13%, respectively) and Others (6% and 6%, respectively). Multivariate Cox proportional hazards analysis of outcomes based on race with 8th edition AJCC pT stage and adjuvant therapy as covariates revealed 6.8 times greater risk for orbital tumour recurrence in Hispanics compared to Caucasians (p = 0.010) and 3.2 times risk hazards for metastasis-related death in Hispanics and Asians compared to Caucasians (p = 0.028 and p = 0.038, respectively). The histopathological features in primarily enucleated eyes with retinoblastoma vary with race. Despite adjusting for tumour staging and adjuvant treatment, race remains an independent predictor of outcomes, including orbital tumour recurrence and metastasis-related death. A stringent follow-up and a more aggressive treatment approach is recommended in Asians and Hispanics who manifest high-risk histopathological features.

Evaluation of electrical impedance spectroscopy of bovine eyes for early detection of uveal melanoma

Uveal melanoma is the most common primary intraocular cancer in adults and is an aggressive malignancy with risk to vision and survival. Early detection and timely management of tumors may help preserve vision and reduce mortality rate but is challenging as many tumors are asymptomatic until they become large. Here, we studied the electrical properties of eyes to investigate a novel method for potentially detecting small intraocular tumors. We used finite element analysis to simulate the impact of uveal melanoma tumors on electrical impedance and current density in eye models. We also measured the impedance and current flow in the presence of inserted tissue simulating an intraocular tumor in enucleated bovine eyes and eyes in bovine head ex vivo. Our results showed that a 5 mm-diameter mass was detected inside a 32-mm diameter bovine eye by the impedance analyzer.

Near-infrared imaging retinal diagnostic applications-a review.

Near-infrared reflectance (NIR) is a commonly performed noncontact and rapid imaging technique. This paper reviews the clinical applications of NIR for diagnosing and monitoring retinal diseases. A comprehensive search was conducted across the Pubmed database. A total of 105 articles were finally included in this article. Images were acquired from the authors own clinical experience. The article describes the imaging utility of NIR for diagnosing and deomonstrating findings in various conditions. These include retinal vascular diseases, age-related macular degeneration (AMD), vitreoretinal interface pathologies, retinal dystrophies, inflammatory chorioretinopathies, phakomatoses, retinal toxicities, photic injury, choroidal cavitary lesions, choroidal neoplasms, and choroidal Vascular Lesions. NIR is widely acquired during OCT imaging, and is advantageous at imaging with low illumination levels and through narrow pupils or opaque media. NIR offers valuable information for the diagnosis and follow-up of retinal disease, and is highly recommended to utilize for clinical decision-making in ophthalmology.

In vitro model of retinoblastoma derived tumor and stromal cells for tumor microenvironment (TME) studies

Retinoblastoma (RB) is an intraocular tumor arising from retinal cone progenitor cells affecting young children. In the last couple of years, RB treatment evolved towards eye preserving therapies. Therefore, investigating intratumoral differences and the RB tumor microenvironment (TME), regulating tumorigenesis and metastasis, is crucial. How RB cells and their TME are involved in tumor development needs to be elucidated using in vitro models including RB derived stromal cells. In the study presented, we established primary RB derived tumor and stromal cell cultures and compared them by RNAseq analysis to identify their gene expression signatures. RB tumor cells cultivated in serum containing medium were more differentiated compared to RB tumor cells grown in serum-free medium displaying a stem cell like phenotype. In addition, we identified differentially expressed genes for RB tumor and stromal derived cells. Furthermore, we immortalized cells of a RB1 mutated, MYCN amplified and trefoil factor family peptid 1 (TFF1) positive RB tumor and RB derived non-tumor stromal tissue. We characterized both immortalized cell lines using a human oncology proteome array, immunofluorescence staining of different markers and in vitro cell growth analyses. Tumor formation of the immortalized RB tumor cell line was investigated in a chicken chorioallantoic membrane (CAM) model. Our studies revealed that the RB stromal derived cell line comprises tumor associated macrophages (TAMs), glia and cancer associated fibroblasts (CAFs), we were able to successfully separate via magnetic cell separation (MACS). For co-cultivation studies, we established a 3D spheroid model with RB tumor and RB derived stromal cells. In summary, we established an in vitro model system to investigate the interaction of RB tumor cells with their TME. Our findings contribute to a better understanding of the relationship between RB tumor malignancy and its TME and will facilitate the development of effective treatment options for eye preserving therapies.

Endoscopic Endonasal Approach to the Inferolateral Intraconal Orbit: An Anatomical Analysis of Exposure and Maneuverability.

Endoscopic endonasal techniques, initially developed for sinonasal tumor resection, have revolutionized the approach to orbital lesions. The emergence of endonasal orbital tumor surgery has prompted anatomical studies focusing on the medial orbit, yet there remains a lack of literature on maneuverability lateral to the optic nerve (ON), with current feasibility assessments relying primarily on the plane of resectability (POR). Bilateral anatomical dissections were conducted on four latex-injected human cadaveric heads using an endoscopic medial and inferior orbitotomy and superomedial displacement of the inferior rectus muscle (IRM) to access the inferolateral intraconal quadrant. Measurements of distances, areas, angles of attack, and volumetric exposure were obtained using stereotactic points from an imaging-based navigation system. Additionally, an illustrative case was presented to demonstrate the endoscopic management of laterally based intraconal lesions. The intraconal space was safely accessed through superomedial displacement of the IRM. The mean intraconal volumetric exposure attained through this maneuver was 2.78cm3 (1.18cm3). The most superolateral point reachable by the ipsilateral endoscopic endonasal approach was consistently lateral and superior to the ON at a mean absolute distance of 1.45cm (0.37cm). Maneuverability at this target point was superior in the sagittal plane, noted by a larger vertical angle of attack compared with the horizontal angle of attack. This study demonstrates that inferolateral intraconal dissection through an ipsilateral endoscopic endonasal approach is feasible via a medial orbitotomy and superomedial retraction of the IRM. Additionally, our findings reaffirm lesions below the POR are suitable for endoscopic endonasal resection.

Iatrogenic Erosion of Orbital Walls due to Expanding Hydrogel Explant.

Hydrogel scleral buckles are a hydrophilic explant that may lead to significant delayed complications. They can insidiously enlarge over decades and may mimic an orbital tumor or cyst. The authors report a case of an expansive hydrogel scleral explant in a previously eviscerated socket. A 58-year-old male presented with a 2-week history of severe pain in his left anophthalmic socket. And 31 years prior, he had sustained OS trauma and undergone a series of surgeries. Details of these procedures were unavailable; however, he had ultimately proceeded to globe evisceration. MRI revealed a large lobulated cyst-like orbital mass with internal calcification, which had expanded the left orbit with erosion of the medial wall, lateral wall, and roof. It extended to involve the ethmoid and frontal paranasal sinuses. He proceeded to a lateral orbitotomy, revealing the lesion to be an expanded hydrogel scleral buckle explant. Postoperatively, there was a significant improvement in his pain.

Clinical and Genetic Characteristics of Patients with Peripheral Retinal Flecks in Koreans.

To describe the clinical and genetic features of Korean patients with peripheral retinal flecks unrelated to aging. A retrospective analysis was conducted on the clinical characteristics of patients with symmetric peripheral retinal flecks. Age-related deposits such as reticular pseudodrusen were excluded, as well as secondary deposits related to intraocular inflammation, tumor, and drug toxicity. Multimodal imaging, electrophysiological examinations, and genetic testing were analyzed. A total of 10 patients (two men and eight women) with bilateral peripheral flecks were enrolled in this study. A mean age at diagnosis was 30.5 ± 19.6 years (range, 4-59 years). Within the 10 patients, six were genetically confirmed with monogenic retinal disorders. Biallelic pathogenic variants in RDH5 were found in five patients, and one patient was diagnosed with retinopathy related to Alport syndrome due to a pathogenic variant in COL4A5. Although not genetically confirmed, one case associated with nanophthalmos and another case showing chorioretinal mottling in a carrier of ocular albinism have been identified. In one patient, genetic testing also revealed unknown causes. The mean logarithm of the minimum angle of resolution initial visual acuity was 0.12 ± 0.18 and 0.07 ± 0.18 in right and left eyes, respectively. Night blindness was reported by four patients (40%), with three showing decreased or delayed rod response in electroretinogram, particularly those with RDH5 mutations. Differences in the deposit layers and the patterns of flecks were observed on multimodal imaging. In the study population, we observed various causes and clinical differences in the retinal fleck patterns among Koreans, including RDH5-related fundus albipunctatus and Alport syndrome. Despite reports of night blindness symptoms in some cases, all patients demonstrated satisfactory corrected visual acuity.

Diffuse iris melanoma leading to secondary glaucoma in a lion (Panthera leo)-A case report.

To describe the case of a 12-year-old male African lion (Panthera leo) presented with ocular discharge, corneal edema, and buphthalmos of the right eye. Ocular ultrasonography showed an intraocular mass involving the iris and ciliary body. Enucleation was performed. Subsequent histopathological analysis revealed a pleomorphic pigmented neoplastic cell population infiltrating, expanding and effacing the iris and ciliary body and occupying the ciliary cleft. The histopathological and immunohistochemical features were consistent with a diffuse iris melanoma (DIM). DIM is the most common primary intraocular neoplasm of domestic cats, but rarely reported in large felids. The prognosis in large felids is unknown and warrants identifying additional cases and careful monitoring of affected individuals.

Tissue Glue-Assisted Plaque Radiotherapy for Choroidal Tumors with Scleral Thinning.

To evaluate tissue glue-assisted plaque placement regarding accuracy, stability, and longer-term outcomes for choroidal tumors with scleral thinning. All patients with tissue glue-assisted plaque radiotherapy at a single ocular oncology center were evaluated for patient demographics, tumor features, surgical details, tumor response, and glue-related complications. There were 13 patients (mean age 72 years) treated with tissue glue-assisted plaque radiotherapy for choroidal melanoma (n=12) or choroidal metastasis (n=1). At presentation, the tumor was mean 4.3 mm to the optic disc and 2.0 mm to the foveola with mean basal diameter of 9.5 mm and thickness of 4.2 mm. In all cases, the tissue glue-assistance was employed due to extreme scleral thinning in the bed of proposed radiation. The plaque size was 15 mm (n=5), 18 mm (n=7), or 20 mm (n=1). At application, there was no immediate glue hypersensitivity, ultrasonography confirmed accuracy of placement, and the glue remained adherent for the entire treatment duration (mean 113 hours) with stable plaque location at removal. At removal, the plaque-glue composite was peeled off the globe without need for glue dissolvent and without scleral disruption. At 12 months mean melanoma thickness (2.7 mm, regression 36%). There were no conjunctival, corneal, or scleral complications. Tissue glue-assisted plaque radiotherapy is safe and effective for treatment of choroidal tumors with thin sclera.

CACA guidelines for holistic integrative management of retinoblastoma

Retinoblastoma is the most common intraocular malignant tumor that poses a serious threat to the lives of children. Treatment plans for RB vary depending on the stage of the disease, and there is an uneven distribution of medical resources across different regions. To standardize the clinical diagnosis and treatment of RB, experts have conducted extensive discussions and proposed guidelines for RB diagnosis and treatment. These guidelines aim to improve the clinical management of RB and serve as a reference for clinicians in their practice.

Trainee experience in virtual reality simulation in orbital surgery

ABSTRACT Purpose To demonstrate the role of Virtual Reality (VR) in orbital surgery as an educational tool for surgical trainees. Methods A single-center prospective study was conducted from February 2021 to April 2023. Pre-operative magnetic resonance imaging and computed tomography scans were used to create patient-specific VR models of the orbit using ImmersiveTouch Software. Accuracy of the models was qualitatively assessed by an attending oculofacial surgeon. Surveys regarding understanding of the surgical plan were distributed to trainees before the VR simulation, after its use, and following surgery. Results VR models were made for 28 cases, and 52 surveys were completed by residents in ophthalmology, otolaryngology, plastic surgery, and by oculofacial fellows. The VR models for 93% of the cases were rated as accurate by the attending physician. Assigned trainee tasks included measurement of an orbital fracture (n = 1, 1.9%), measurement of orbital tumors (n = 12, 23.1%), and drilling of the orbital bone to simulate an orbital decompression (n = 10, 19.2%). The tumor measurements made by trainees using the VR system were not significantly different than those recorded by the radiologists (p > 0.05). Early trainees (i.e. residents and the first year oculofacial fellow) noted significant improvement in their understanding of the pathology relative to important anatomical landmarks within the orbit after utilizing the VR models prior to surgery (p < 0.001). Conclusions Patient-specific VR models accurately simulate orbital pathology and may improve trainees’ understanding of orbital anatomy early in their careers.

Case Report: Periocular Steroid Injection Combined Vemurafenib Therapy in the Long-term Management of Orbital Involvement of Erdheim-Chester Disease.

Abstract Purpose: To report a rare case of vision loss from Erdheim-Chester Disease (ECD) and long term, follow up, management and results. Case Report: A 62-year-old woman presented with bilateral exophthalmos and deterioration in visual acuity of both eyes. Magnetic resonance imaging studies revealed bilateral intraconal orbital tumors. She was diagnosed optic neuropathy in both eyes. The patient was treated with pegylated interferon and systemic pulse steroid. However, recurrences were common. Subsequently, the patient underwent regular corticosteroid injection directly into the retro-orbital region of both eyes monthly, which led to intermittent improvement of vision. At the 8th month of visual impairment, Vemurafenib was initiated. Results: The visual acuity and visual field scores were stable for 6 years during the follow-up. No major complication was observed. Conclusion: Combined vemurafenib and perioculer steroid injection is a well tolerated therapy with less systemic adverse effects which may benefit patients with orbital involvement of ECD. Key words: Erdheim–Chester disease; compressive optic neuropathy; vemurafenib; Optical coherence tomography; Optical coherence tomography angiography.

POSSIBLE ERRORS IN THE DIAGNOSIS OF INTRAOCULAR TUMORS

Rationale: The article discusses difficulties in the differential diagnosis of intraocular tumors (IOT), particularly in cases of small choroidal melanoma. Despite a substantial number of publications dedicated to the diagnosis of intraocular tumors, difficulties in interpreting imaging methods, such as optical coherence tomography (OCT), persist.Objective: to analyze the OCT patterns that have led to diagnostic errors.Methods: We analyzed the OCT results of 15 patients whose diagnosis of «choroidal hemangioma» was revised to «choroidal melanoma» in 11 cases or «progressive nevus» in 4 cases. The mean age at the time of IOT detection was 50.20±13.08 years (range: 35–79 years); the average tumor prominence was 2.22±0.82 mm (range: 1-3.6 mm), and the average diameter was 8.01±2.72 mm (range: 3.11–11.5 mm). A detailed analysis of the specific OCT patterns that led to diagnostic errors was conducted.Results and discussion: The characteristics of the identified OCT patterns that frequently caused diagnostic difficulties were thoroughly examined, such as cystic changes and the «subretinal cleft» phenomenon. Cases in which complex OCT patterns overlapped with both melanoma and hemangioma were also analyzed, reinforcing the need for a multimodal approach to the interpretation of imaging data. Conclusion: for accurate diagnosis and to avoid erroneous planning of treatment strategies, OCT should be evaluated within the context of the clinical picture and patient history.

High-Risk Histopathological Features of Retinoblastoma following Primary Enucleation: A Global Study of 1426 Patients from 5 Continents.

To evaluate high-risk histopathological features (HRHF) following primary enucleation of eyes with retinoblastoma (RB) and assess the patient outcomes across continents. Retrospective study of 1426 primarily enucleated RB eyes from five continents. Of all, 923 (65%) were from Asia (AS), 27 (2%) from Australia (AUS), 120 (8%) from Europe (EUR), 162 (11%) from North America (NA), and 194 (14%) from South America (SA). Based on the continent (AS vs. AUS vs. EUR vs. NA vs. SA), the histopathology features included massive choroidal invasion (31% vs. 7% vs. 13% vs. 19% vs. 27%, p=0.001), post-laminar optic nerve invasion (27% vs. 0% vs. 16% vs. 21% vs. 19%, p=0.0006), scleral infiltration (5% vs. 0% vs. 4% vs. 2% vs. 7%, p=0.13), and microscopic extrascleral infiltration (4% vs. 0% vs. <1% vs. <1% vs. 4%, p=0.68). Adjuvant chemotherapy with/without orbital radiotherapy was given in 761 (53%) patients. Based on Kaplan-Meier estimates in different continents (AS vs. AUS vs. EUR vs. NA vs. SA), the 6-year risk of orbital tumor recurrence was 5% vs. 2% vs. 0% vs. 0% vs. 12% (p<0.001), systemic metastasis was reported in 8% vs. 5% vs. 2% vs. 0% vs. 13% (p=0.001), and death in 10% vs. 3% vs. 2% vs. 0% vs. 11% (p<0.001) patients. There is a wide variation in the infiltrative histopathology features of RB across continents, resulting in variable outcomes. SA and AS had a higher risk of orbital tumor recurrence, systemic metastasis, and death compared to AUS, EUR, and NA.

Orbital and eyelid inflammatory myofibroblastic tumors: a clinicopathological analysis of 13 cases

Objective: To investigate the clinicopathological features of orbital and eyelid inflammatory myofibroblastic tumors (IMTs). Methods: A retrospective analysis was conducted among 13 patients with IMTs treated at Tianjin Eye Hospital between January 2000 and October 2023. The clinicopathological data, immunohistochemical staining characteristics, molecular phenotypes, and follow-up outcomes were collected and analyzed. Results: The study cohort comprised 7 males and 6 females. The median age was 44 (22, 68) years. The tumor was observed in the left eye in 6 cases and the right eye in 7 cases. The age at onset ranged from 5 to 76 years, with a disease course of 1 month to 2 years before tumor excision. The tumor was located within the orbit in 10 cases (including one case of a systemic multifocal lesion) and in the eyelid in 3 cases. Pathological characteristics of the tumors were mainly proliferation of spindle or ovoid fibroblasts and myofibroblasts, with varying degrees of mucoid degeneration or collagenization of the mesenchyme, and varying amounts of lymphocytes and plasma cells infiltrated in the background. Immunohistochemical analysis revealed that Vimentin and α-SMA were positive in all cases (13/13, 13/13), ALK1 was positive in 5 cases (5/11), CK was positive in 1 case (1/1), and Desmin was positive in 1 case (1/6). ALK fluorescence in situ hybridization was positive in 2 out of 3 cases, and EBER in situ hybridization was negative in 6 cases. Nine patients were available for the follow-up of 7 to 139 months. Seven patients remained tumor-free, 2 experienced relapses, and no deaths or metastases were reported. Conclusions: Orbital and eyelid IMTs predominantly occurred in adults, with localized lesions in most cases and favorable prognoses. The disease was histopathologically characterized by proliferation of fibroblasts and myofibroblasts. The accurate diagnosis depended on a comprehensive assessment of the morphological features of the tumor histopathology as well as immunohistochemical markers such as ALK and α-SMA, and molecular detection.