OBJECTIVE: Within the large umbrella of histiocytosis are a few similar yet heterogenous entities involving the orbit and periocular tissues with or without systemic infiltration, termed adult onset xanthogranuloma or orbital xanthogranuloma. Due to rarity of these conditions, different classifications in use, diverse clinical presentations and still unknown etiology, the aim of this paper was to provide an up-to-date literature review of the actual understanding of histiocytosis and its subgroups involving the orbit and periocular area, diagnostic strategies and therapeutic modalities.
METHODS: We present a review of literature and small case series comprising four patients diagnosed and treated in the period from 2001 until 2023 in our hospital. Clinical files of 4 patients with adult-onset xanthogranulomatous disease of the orbit and ocular adnexa (AOXGD) were reviewed retrospectively. Clinical, laboratory, radiological, histopathological, and immunohistochemical findings were reexamined.
RESULTS: Reviewing medical records of our patients with AOXGD, we found significant overlap between histiocytosis and different immune disorders. A broad workup should be considered in these patients as they can harbour severe immune disfunctions and hematologic disorders. Preferred treatment modality depends on a histopathologic type of AOXGD, clinical presentation and systemic involvement and should be conducted multidisciplinary.
CONCLUSIONS: The diagnosis is often delayed because of its rarity and diverse clinical findings. Development of molecular genetic tests, detection of BRAF V600E mutation and different types of kinase mutations, mutations in transcriptional regulatory genes as well as tyrosine kinase receptors have shed a new light on the etiopathogenesis and potential targeted treatment of histiocytosis.

Juvenile xanthogranuloma (JXG) is a rare, benign non-Langerhans cell histiocytosis that primarily affects the skin, with infrequent extracutaneous manifestations. Lesions typically emerge during early childhood and often resolve spontaneously, obviating the need for treatment. This paper details the case of a child diagnosed with a solitary JXG on the sole, necessitating surgical excision due to its functional impairment, specifically a delay in walking and weight bearing.

Sellar xanthogranulomas are extremely rare intracranial lesions, particularly in pediatric patients, and their diagnostic and therapeutic challenges prompt thorough investigation. We describe a case of a two-year-old toddler diagnosed with sellar xanthogranuloma, highlighting the challenges encountered in its diagnosis and management. The child presented with symptoms, including headache, ptosis of the left eye, and neurological deficits. Brain computed tomography (CT) and magnetic resonance imaging (MRI) revealed a hypodense sellar lesion. The patient underwent a left pterional craniotomy for resection of the mass. Histopathological examination suggested the diagnosis of sellar xanthogranuloma, characterized by foamy macrophages, giant cells, lymphocytic infiltrates, fibrous proliferation, necrotic detritus, and hemosiderin deposits. Further diagnostic precision was achieved through immunohistochemical staining, including CD1a and langerin, which successfully ruled out the possibility of Langerhans cell histiocytosis (LCH), reinforcing the diagnosis of sellar xanthogranuloma. The successful surgical resection of the lesion led to a favorable outcome, evidenced by the significant alleviation of symptoms as well as the restoration of normal neurological function. Post-operative assessments demonstrated a marked improvement in the patient\'s quality of life, and there were no observed complications or recurrence of the lesion during the follow-up period. In summary, our case report not only highlights the rarity and diagnostic challenges of sellar xanthogranulomas but also emphasizes the importance of collaborative medical expertise in achieving accurate diagnosis and successful therapeutic outcomes in pediatric patients. The successful management of this case offers valuable insights into the clinical presentation, diagnostic complexities, and treatment strategy of sellar xanthogranulomas, further enriching our understanding of this uncommon intracranial pathology.

UNASSIGNED: Xanthogranuloma of the sellar region is an extremely rare benign entity with only case reports and series documented in the literature. We aim to describe in this report a case of a suprasellar xanthogranuloma that was diagnosed initially as a cystic craniopharyngioma.
UNASSIGNED: A 28-year-old woman presented to the clinic with a 2-week history of headaches, blurred vision, nausea, and vomiting. She had no medical or surgical history, no signs of hormonal disturbances, and no family history of brain tumors or endocrine diseases. Her neurological examination was unremarkable except for bitemporal hemianopia on visual field testing. A magnetic resonance imaging of the brain showed a cystic mass in the sellar region that was compressing the optic chiasm with radiological features representing cystic craniopharyngioma. She underwent endoscopic transnasal transsphenoidal surgery to excise the mass, and only subtotal excision was achieved to preserve the pituitary function. The histopathology confirmed the diagnosis of a xanthogranuloma of the sellar region. The postoperative course was unremarkable, and she did not receive any adjuvant therapy. There was no recurrence of the clinical symptoms or the mass during the 18-month follow-up period.
UNASSIGNED: Although xanthogranuloma is uncommon, it should be included in the differential diagnosis of sellar/suprasellar lesions. Due to its wide range of radiological features that sometimes can mimic other lesions, a definitive diagnosis can only be made postoperatively. Surgical excision is the most accepted treatment with a favorable prognosis and low rates of recurrence.

This report describes an unusual and diagnostically challenging case of subcutaneous soft tissue xanthogranulomas of bilateral orbits of a 58-year-old female patient seen in a private oculoplastics practice. Accurate and timely diagnosis is crucial in xanthogranulomatous diseases so that any systemic manifestations can be identified and addressed in a multidisciplinary fashion. Periorbital xanthogranuloma is a frequent early manifestation of adult xanthogranulomatous disease, and its association with life-threatening systemic disease requires accurate diagnosis and prompt work-up. This case describes an otherwise asymptomatic patient who presented with bilateral orbital masses causing visually significant ptosis, initially diagnosed as soft tissue xanthomas, and later identified as xanthogranulomas. It is important for physicians of all fields, from primary care to surgical subspecialty, to be aware that xanthogranulomatous disease may first present as periorbital lesions and/or orbital masses, and that further work-up for vision and life-threatening systemic disease is warranted.

BACKGROUND: A urachal mass is a relatively rare presentation to the urologists\' practice, often requiring radical surgical excision for a definitive diagnosis. Xanthogranulomatous inflammation of the urachus is an extremely rare entity with few cases reported worldwide, and to the best of our knowledge, no cases reported in the western world.
METHODS: In this case, a 55-year-old male patient presented with bothersome lower urinary tract symptoms and computed tomography findings demonstrating a urachal mass that was worrisome for urachal carcinoma. Following surgical intervention, histopathology revealed urachal xanthogranuloma. Post-operatively, the patient recovered well, and eventually, he had symptomatic and radiologic improvement.
CONCLUSIONS: This case brings awareness to a rare presentation of a urachal mass-urachal xanthogranuloma. While operative intervention was both diagnostic and therapeutic, we highlight the challenge in differentiating between benign and malignant processes for urachal masses. Herein, we show the importance of including urachal xanthogranuloma in the differential diagnosis of a urachal mass to prevent further morbidity associated with the treatment of this disease.

Juvenile Xanthogranuloma (XG) is a rare disorder that belongs to the heterogeneous group of histiocytic neoplasms, characterized by a clonal expansion of non-Langerhans cell histiocytes that share a dermal macrophage phenotype. Although the head and neck region is the most common reported site of involvement by the Juvenile Xanthogranuloma family, laryngeal localization is extremely rare. We report a unique case of Adult Onset Xanthogranuloma with subglottic localization, presenting as a solitary laryngeal mass without other systemic or cutaneous lesions. A review of the previously described cases of laryngeal Xanthogranuloma has been performed, highlighting 7 cases of Juvenile Xanthogranuloma and only 3 cases of Adult Onset Xanthogranuloma. Despite the extreme rarity of laryngeal localization of XG, this histiocytic neoplasm should be considered as a differential diagnosis for laryngeal masses causing airway obstruction, even in the absence of other concomitant manifestations.

Xanthogranuloma is a benign histiocytic disorder that generally appears in infants and children and often called juvenile xanthogranuloma (JXG). Typical reddish-yellow cutaneous papules or nodules are the most common presentation of JXG. Extracutaneous JXG affects eyes, brain, lungs, liver, spleen, and other sites. Isolated ocular manifestation without skin lesion is rare, especially in adult patients. Here, we report a case of a 27-year-old man who presented with gradually growing yellowish mass at the corneoscleral area of the left eye for 5 months. The patient had worn soft contact lenses for more than 10 years. With atypical age of onset and the absence of skin lesion, total mass excision with lamellar corneoscleral graft and amniotic membrane transplantation was done, and the diagnosis of adult-onset limbal xanthogranuloma was made by histopathological and immunohistochemical examinations. Postoperatively, the patient had good vision with corrected distant visual acuity of 20/30, and the graft was clear. There was no evidence of recurrence at 4-year follow-up. We found that excision with lamellar corneoscleral graft in limbal xanthogranuloma shows good result with no recurrence. The same result occurred to other previous cases reported, so complete excision with graft could be an effective treatment of choice in patient with limbal xanthogranuloma.

Langerhans cell histiocytosis (LCH) and adult-onset xanthogranuloma (AXG) are rare disorders characterized by the accumulation of macrophage, dendritic cells, or monocyte-derived cells in various tissues of the body. Many researchers now consider LCH a form of malignancy, but this classification remains controversial. As per our knowledge, there are only 36 cases of AXG reported so far in the English literature. Here, we report a case of AXG and single-system LCH found in the oral cavity and cervical lymph nodes, respectively. In this article, we intend to define a clear understanding of some classic clinical, radiological, and histopathological findings of LCH and AXG, to differentiate them from oral malignancies. The primary goal of this article is to increase awareness regarding conditions that closely resemble malignancies and to save patients from the burden of extensive treatment under the presumption of malignant disorders. In the medical field, reporting of rare cases is highly encouraged; however, proper treatment for the patient depends on the accurate diagnosis that, in this case, was made postoperatively, which only added more physical and mental distress for the patient and their family.

The urachus is a midline tubular structure that extend between bladder dome and umbilicus which result from incomplete regression during normal development. Defective obliteration of the urachus is rare and can result in urachal abnormalities, most commonly malignant masses. Xanthogranulomatous urachal masses are rare forms of chronic inflammatory processes with only few reported cases. Differentiating malignant from benign urachal lesion is challenging due to lack of typical clinical and radiologic manifestations, coupled with limited diagnostic experience or awareness. We present an initial misdiagnosis of urachal carcinoma, which was revealed to be benign xanthogranulomatous inflammation of urachus on postoperative histopathological examination.