Clinicopathological study of ophthalmic cutaneous and mucocutaneous non-langerhans cell histiocytic lesions.

BACKGROUND: The "C group" of the histiocytic disorders is characterized by non-Langerhans-cell histiocytic lesions in the skin, mucosal surfaces, or both, out of which Juvenile xanthogranuloma (JXG) is the most common typically affecting the skin. The eye is the most common extra-cutaneous site of JXG., we aim at providing our clinical and histopathological experience with this group of diseases including the adult-onset xanthogranuloma (AXG). METHODS: This is a retrospective cohort study of all patients with the tissue diagnosis of ocular and periocular cutaneous and mucocutaneous non-LCH disorders who presented to us over a period of 25 years (January 1993 to December 2018). RESULTS: Twenty patients were diagnosed as "Group C" disease with an age range of 2 months-60.9 years. Eleven patients were females (55%) and nine were males (45%). The involvement was mostly unilateral in 80.9%. All cases fell into the xanthogranuloma family with 11 JXG patients, 8 AXG patients of skin and ocular surface, and one patient with solitary reticulohistiocytoma (SRH). The clinical site of involvement in JXG was primarily in the eyelid in 5 patients (45%), ocular surface lesions in 2 (18%), iris in 2 (18%), choroidal and bilateral orbital lesions in 1 patient each (9%). The group of AXG, presented equally with eyelid lesions in 4/8 and ocular surface lesions in 4/8. The non-Langerhans' histiocytic infiltrate showed supportive immunohistochemical staining properties (reactive to CD68 marker and negative to S-100 and langerin markers). CONCLUSION: Among the rare histiocytic disorders, xanthogranulomatosis is the commonest and has wide clinical manifestations. Accurate diagnosis needs to be supported by typical histopathological findings. JXG was the commonest in our study with relatively older mean age at presentation and frequent eyelid rather than iris involvement. AXG is often confused with xanthelasma when involving the eyelids with corneal limbal involvement is relatively frequent.

Systemic xanthogranuloma involving bone marrow and skin in a case of B-Lymphoblastic Leukemia.

Juvenile xanthogranuloma is a benign self-limiting lesion commonly described in infants and young children. It most commonly involves the skin presenting as single or multiple yellowish-brown papules. Clinical scenario with the classic histomorphology showing histiocytic aggregates in the dermis with xanthomatous cytoplasm, toutan type giant cells, immunohistochemistry with positive CD68, CD163, factor XIIIa and negative CD1a and S-100 help in diagnosis. However, diagnosis becomes challenging with predominant systemic bone marrow involvement in post-B-lymphoblastic leukemia settings.

Histopathological maturation in juvenile xanthogranuloma: a blueberry muffin infant mimicking aleukemic leukemia cutis.

Juvenile xanthogranuloma (JXG) is usually identified by Touton giant cells, so their absence can complicate diagnosis. We encountered a case of non-typical neonatal JXG lacking Touton giant cells, which was difficult to differentiate from aleukemic leukemia cutis because of overlapping histopathological characteristics. A 1 month-old girl presented with a blueberry muffin rash and multiple 1-2 cm nodules within the subcutaneous and deeper soft tissues. Blood tests revealed pancytopenia. The initial nodule biopsy showed mononuclear cell infiltration, suggestive of mature monocytes or histiocytes, but no Touton giant cells. Bone marrow examination showed no evidence of leukemia. Despite worsening of the rash, pancytopenia, and weight gain over the following month, the results of the second biopsy remained consistent with the initial findings. Consequently, we provisionally diagnosed aleukemic leukemia cutis and initiated chemotherapy. After two courses of chemotherapy, the pancytopenia improved, but the nodules only partially regressed. A third biopsy of the nodule was performed to evaluate the histological response, and revealed Touton giant cells, confirming the diagnosis of JXG. In conclusion, distinguishing non-typical JXG from aleukemic leukemia cutis is challenging. This case highlights the importance of multiple biopsies and the potential for histopathological maturation.

[Giant and ulcerated juvenile xanthogranuloma: an atypical presentation in infants]. / Xantogranuloma juvenil gigante y ulcerado: una presentación atípica en lactantes.

Giant Juvenile Xanthogranuloma (GJXG) corresponds to an infrequent variant of Juvenile Xantho- granuloma (JXG) and is characterized by a lesion larger than 2 cm in diameter. It usually presents as a plaque but infrequently, presents as an ulcerated nodule. OBJECTIVE: To report two cases of atypical presentation of GJXG, highlighting the importance of considering them in the differential diagnosis of large, ulcerated tumors in infants. CLINICAL CASES: Case 1: A 4-month-old healthy male infant presented with a rapid and progressive growing left inguinal nodule, present since 2 months of age. At physical examination he presented with a 2.6 cm indurated erythematous nodule with central ulceration. Histological study of an incisional biopsy was compatible with JXG. Ophthalmologic involvement was ruled out. Because of functional impairment and parents worry complete surgical removal was performed. The patient had favorable evolution without local recurrence at 4 years of follow-up. Case 2: A 6-month-old healthy male infant presented with a 2.4 cm scapular crusted nodule of rapid and progressive growth, present since birth. Histological study of an incisional biopsy confirmed JXG. Ophthalmologic involvement was ruled out. After 18 months of periodic clinical follow-up, there was a progressive reduction in size of the lesion. CONCLUSIONS: The cases presented highlight the importance of considering JXG in the differential diagnosis of large, ulcerated tumors in infants. When encountered to atypical JXG presentations, histologic studies help to confirm the diagnosis. Given the favorable prognosis of this diagnosis, periodic clinical follow-up is advised; in exceptional cases, surgical or ablative treatments may be considered.

Expanding Our Knowledge of Molecular Pathogenesis in Histiocytoses: Solitary Soft Tissue Histiocytomas in Children With a Novel CLTC::SYK Fusion.

The histiocytoses comprise a histopathologically and clinically diverse group of disorders bearing recurrent genomic alterations, commonly involving the BRAF gene and mitogen-activated protein kinase pathway. In the current study, a novel CLTC :: SYK fusion in 3 cases of a histopathologically distinct histiocytic neoplasm arising as solitary soft tissue lesions in children identified by next-generation sequencing and fluorescence in situ hybridization is described. Morphologically, all 3 neoplasms were composed of sheets of cells with round-oval nuclei and vacuolated eosinophilic cytoplasm but, in contrast to classic juvenile xanthogranuloma (JXG), Touton giant cells were absent. A separate cohort of classic JXG cases subsequently profiled by fluorescence in situ hybridization were negative for the presence of a CLTC::SYK fusion suggesting that CLTC::SYK fusion-positive histiocytoma is genetically and histologically distinct from JXG. We postulate that the CLTC::SYK fusion leads to aberrant activation of the SYK kinase, which is involved in variable pathways, including mitogen-activated protein kinase. The identification of a novel CLTC::SYK fusion may pave the way for the development of targeted therapeutic options for aggressive disease.

Juvenile xanthogranuloma as a differential diagnosis for sellar and suprasellar lesions in child: Case report and review of literature.

Juvenile xanthogranuloma (JXG) is a rare type of non-Langerhans cell histiocytosis. Its systemic form affects 4% of patients. Lesions in the Central Nervous System (CNS) occur in 2% of systemic cases. Sellar JXG should be one of the differential diagnoses for sellar lesions in young. This is a 15-year-old patient with non-specific headache, progressive visual loss and magnetic resonance imaging showing sellar lesion with suprasellar extension. The patient underwent microsurgery by pterional craniotomy with partial resection of the tumor. Pathology evidenced JXG. It progressively evolved with impairment of neuroendocrine functions, new lesions in different CNS locations and death two years after diagnosis. Sellar JXG without cutaneous manifestations is rare. There are no specific findings of the disease. Diagnosis requires additional tests, being defined by pathological analysis. Total resection presents a greater potential control comparing to partial resection. Even so, some patients may have progressive disease with poor clinical outcome.

Langerhans Cell Histiocytosis Evolving into Juvenile Xanthogranuloma: Two Linked Entities.

BACKGROUND: Langerhans cell histiocytosis (LCH) represents a myeloid clonal proliferation that involves the skin and other organs. Occasionally, cases of LCH evolve into juvenile xanthogranuloma (JXG). CASE PRESENTATION: A 7-month-old boy presented with an itchy, flaky rash resembling seborrheic dermatitis affecting the scalp and eyebrows. The lesions started at 2 months old. On physical examination, there were reddish/brown lesions on the trunk, denuded areas on the groin and neck, and a large lesion behind his bottom teeth. In addition, there were thick white plaques in his mouth and thick whitish material in both ears. A skin biopsy showed features of LCH. Radiologic examination demonstrated several osteolytic lesions. Chemotherapy produced marked improvement. A few months later, the patient developed lesions with clinical and histologic features of XG. CONCLUSION: A possible association between LCH and XG is explained by lineage maturation development. Chemotherapy may play a role in modifying the production of cytokines that enhance the transformation or 'maturation' of Langerhans cells into multinucleated macrophages (Touton cells) characteristic of a more favorable proliferative inflammatory condition.

Imaging features of juvenile xanthogranuloma.

BACKGROUND: Juvenile xanthogranuloma is rare in children and there are limited data on its imaging features. OBJECTIVE: To analyze the computed tomography (CT) and magnetic resonance imaging (MRI) features of juvenile xanthogranuloma in children. MATERIALS AND METHODS: A retrospective review was performed of clinical and radiographic data of histologically confirmed juvenile xanthogranuloma between January 2009 and June 2020. RESULTS: Fourteen children (4 girls, 10 boys; age range: 1 day to 13 years, mean age: 73 months) were included in the study: 4/14 had CT only, 5/14 had MRI only and 5/14 had CT and MRI. Sites of extracutaneous juvenile xanthogranuloma involvement included subcutaneous soft tissue (8/14), liver (2/14), lungs (2/14), kidney (2/14), nose (2/14), pancreas (1/14), central nervous system (1/14) and greater omentum (1/14), mainly manifested as single or multiple nodules or masses in different organs. On CT, the lesions mainly manifested as an iso-hypo density mass with mild or marked enhancement. On MRI, the lesions mainly manifested as slightly hyperintense on T1 and slightly hypointense on T2, with decreased diffusivity and homogeneous enhancement. Juvenile xanthogranuloma was not included in the imaging differential diagnosis in any case. CONCLUSION: Juvenile xanthogranuloma mainly manifests as single or multiple nodules or masses in different organs. Slight hyperintensity on T1 and slight hypointensity on T2 with decreased diffusivity and homogeneous enhancement are relatively characteristic imaging findings of juvenile xanthogranuloma. Combined with its typical skin lesions and imaging features, radiologists should include juvenile xanthogranuloma in the differential diagnosis when confronted with similar cases.

Oral Juvenile Xanthogranuloma: a case report of gingival hyperplasia and osteolysis in male adult patient.

BACKGROUND: Juvenile Xanthogranuloma (JXG) is a non-hereditary, self-limiting disease which is usually presented in infancy or early childhood and in males over females. CASE PRESENTATION: We report a rare case of oral Juvenile Xanthogranuloma with recurrent progressive gingival hyperplasia and concomitant presentation of osteolysis in a 21-year-old adult male with no significant medical history. Patient presented with generalized gingival hyperplasia, osteolysis of the maxilla and mandible, and a round, firm, nodular mass with clear circumference on the left shoulder. Results of gingival tissue biopsy, karyotype, bone marrow biopsy and immunohistochemistry were suggestive of a diagnosis of Juvenile Xanthogranuloma with no association to hematologic malignancy. Unfortunately, patient declined treatment and elected to be transferred back to local hospital for future evaluation. CONCLUSIONS: Juvenile Xanthogranuloma in adults can have atypical manifestations including generalized gingival hyperplasia and osteolysis of the maxilla and mandible. It should be differentiated between Langerhans cell histiocytosis, Papillon-Lefevre Syndrome, and Pyogenic Granulomas. Despite uncommon incidence, it should be included in differential diagnoses in cases of similar clinical presentations.

What is the Role of Different Macrophage Subsets in the Evolution of Juvenile Xanthogranulomas?

There are several activated forms of macrophages: 2 main groups are designated M1 and M2. While M1 macrophages have proinflammatory, bactericidal, and phagocytic functions and are the dominant phenotype observed in the early stages of inflammation, M2 macrophages are involved in constructive processes such as tissue repair; they play a role in wound healing and are required for revascularization and re-epithelialization. Juvenile xanthogranuloma (JXG) is the most common non-Langerhans cell histiocytosis. Its pathogenesis is not well understood, but it is not considered a neoplastic entity. JXGs possibly appear as a reaction to a nonspecific injury such as trauma or viral infection, although a genetic predisposition has been suggested in some cases. Tissue damage leads to a histiocytic response. JXGs appear, evolve toward maturation, and then most of them spontaneously regress. Young JXGs are characterized by small macrophages scattered in the dermis, in apposition close to the epidermis. As the lesion matures, the number of foamy macrophages and Touton cells increases and other cell types such as plasma cells, lymphocytes, and polymorphs are observed. Regressing xanthogranulomas will show numerous spindle cells in Significant values are in bold.a storiform distribution, interstitial fibrosis, and few foamy and Touton cells. In this study, we studied the immunophenotypic profile of macrophages found in cutaneous JXGs according to their stage of maturation. We examined the skin biopsies from 25 patients; all were embedded in paraffin and stained with hematoxylin and eosin and for immunohistochemistry. Typically, all JXGs were positive for factor XIIIa and CD4, and were negative for CD1a. The following histiocyte markers were used: CD68, CD204, CD163, MAC387, and HAM56. Images were analyzed by Image J software; data were statistically evaluated by SAS 9.0 software. The cases showed a slight predominance of males and the preference of the JXGs for the axial skin. Lesions occupied the papillary and reticular dermis in 85% of the cases and extended to the subcutaneous fat in the remainder. Compared with mature and regressing JXGs, younger lesions had a higher density of M1 macrophages, stained with MAC387. This antibody labels the histiocytes that have recently arrived in the areas of inflammation. As the lesions matured, there was an overwhelming predominance of M2 macrophages. These cells tended to cluster against the epidermis, except in the 2 cases in phase of regression. This suggests that there is a cross-talk between the epidermis and macrophages and that receptors, cytokines, chemokines, and adhesion molecules may play a role in the development and evolution of JXGs. These results indicate that, for most of their life, JXGs are formed by repairing M2 macrophages and are not just an M1 macrophagic response to a local antigen. The process appears to be influenced by chemical-mediator epidermal-macrophage cross-talking, considering the tendency of these cells to accumulate against the dermoepidermal junction.

Giant Juvenile Xanthogranuloma of face in an adult: A rare complexity.

Juvenile xanthogranuloma, a form of non-Langerhans cell histiocytosis can be defined as the proliferation of cells with macrophage like characteristics. It has been described as a benign, asymptomatic and common self-healing disorder of non-Langerhans cell histiocytosis (LCH), affecting mostly infants, children and rarely adults. We have documented a case of a 40 year old male who presented to us with extensive insidious papulonodulous growth over the face. The facial disfigurement caused was catastrophic. An extensive surgical excision and reconstruction was performed followed by histopathological evaluation. Microscopic study and immune histochemistry revaled Juvenile Xanthogranuloma of adult. The article highlights the presentation, diagnosis and management of this mammoth, rare disease.

Juvenile and adult xanthogranuloma: A 30-year single-center experience and review of the disorder and its relationship to other histiocytoses.

BACKGROUND: Juvenile xanthogranuloma (JXG) is the most common type of non-Langerhans cell histiocytosis whose cell of origin, etiology and pathogenesis are not fully understood. We aimed to provide an update on histopathologic and immunophenotypic profile of this well-characterized entity whose relationship to the other histiocytoses has received renewed attention in light of recent molecular genetic studies. MATERIALS AND METHODS: A retrospective review of all the cases with the pathologic diagnosis of "xanthogranuloma" was performed on our archives from 1989 to 2019. RESULTS: A total of 525 patients with 547 lesions diagnosed as JXG were identified with the median age of 4.5 years, a male predominance (M:F ratio 1.3:1) and a predilection for the head and neck region (40.8%). Cutaneous lesions comprised 76.8% cases and another 15.7% presented within soft tissues. The most common non-soft tissue, extracutaneous lesions included the brain (2.6%), and lungs (1.8%). Three basic histopathologic patterns were identified: early classic (EJXG) (14.2%), classic (CJXG) (45.3%), and transitional JXG (TJXG) (40.5%). Multinucleated giant cells, either Touton or non-Touton, were most frequently present in CJXG followed by TJXG. Mitosis was rare (<1/10 high-power field) among different patterns. There was an association among the patterns and lymphocytic infiltrates (P = 0.036), and presence of Touton or non-Touton giant cells (P < 0.001 for both) but not for mitotic count (P = 0.105) or eosinophilic infiltrates (P = 0.465). Additionally, there was a correlation between age groups and presence of non-Touton giant cells (P = 0.012) but not for Touton cells (P = 0.127). We have demonstrated that immunophenotypic expression of the lesion was not associated with age at diagnosis nor morphologic pattern: factor XIIIa 192/204 (94.1%), CD11c 75/77 (97.4%), CD4 82/84 (97.6%), CD68 200/201 (99.5%), CD163 15/15 (100%), CD1a 1/110 (0.9%), S-100 48/152 (31.6%), CD31 15/21 (71.4%), and vimentin 104/105 (99.0%). CONCLUSION: We have documented in a substantial series of cases of JXG that there is a correlation between one of the three basic histopathologic patterns with age at diagnosis, but with a consistent immunophenotype among the three patterns. Considering sensitivity and specificity rates, we suggest that a combination of CD11c, CD4, CD1a and either CD163 (preferred) or CD68 stains provides more specific diagnostic yield in the differentiation of JXG from other histiocytic disorders. JXG is also discussed in terms of its relationship and distinction from other similar histiocytic disorders in the context of MAPK/ERK pathway mutations.

Juvenile Xanthogranuloma: A Comparative Immunohistochemical Study of Factor XIIIa, CD11c, and CD4.

ABSTRACT: Juvenile xanthogranuloma is a group C and L non-Langerhans cell histiocytosis, and its cell of origin is still debatable. The expression of CD11c, a more recently described macrophage marker, and CD4 have not been studied comprehensively. This study aimed to expand immunophenotypic profile and hence our understanding of the origin of these lesions. The surgical pathology archive was searched for the cases with the pathologic diagnosis of "xanthogranuloma" from 1995 to 2019. Immunohistochemical (IHC) stains were performed for factor XIIIa, CD11c, and CD4. Morphologically, each lesion was classified into early classic, classic, or transitional subtypes. Seventy-seven cases were included with the median age of 7.8 years (male:female 1.3:1). Uniform positivity was noticed for CD4 (n = 77), CD68 (n = 37), CD163 (n = 5), and vimentin (n = 4) stains. Other stains included CD11c 75/77 (97.4%), factor XIIIa 71/76 (93.4%), S-100 protein 4/23 (17.4%), and CD1a 0/18 (0%). Despite insignificant association between morphologic subtype and main studied IHC stains, factor XIIIa reactivity was highest in transitional lesions and CD11c showed higher reactivity in early classic lesions. CD11c and CD4 are sensitive markers and showed promising results in the diagnosis of juvenile xanthogranuloma compared with factor XIIIa. Despite different reactivity of factor XIIIa and CD11c in various morphologic subtypes, such association was statistically insignificant.

On the knowledge of solitary juvenile xanthogranuloma of the eyelid: a case series and literature review.

PURPOSE: Solitary eyelid juvenile xanthogranuloma (JXG) is extremely rare, and there is limited literature on its clinical features and treatment outcomes. Here, we present a case series and comprehensive review of the literature on patients with isolated eyelid JXG. METHODS: We systematically extracted data from our institution's records of isolated eyelid JXG cases and conducted a search for additional cases from the literature utilising the PubMed, Wanfang, and Chinese National Knowledge Infrastructure (CNKI) databases. Patients with JXG were analysed with respect to age, sex, clinical presentation, therapy, and outcome. Group comparisons were performed. RESULTS: Thirty-two patients (including 13 at our institution and 19 from prior publications) were identified. The median age at first presentation was higher in current patients than in the patients from the published cases (median 9 years, range 1.2 to 47.0 years; median 2 years, range 0.5 months to 46.0 years, respectively, P = 0.014). Of the patients who had known characteristics, no significant differences were observed between the two groups in terms of sex, affected eye, eyelid site, type of cutaneous involvement, or duration of symptoms (each P > 0.05). Seventeen (54.8%) patients were male. The most common lesion location was the upper eyelid (n = 10, 62.5%). Twenty-four (75.0%) cutaneous lesions had full-thickness skin involvement; 8 (25.0%) subcutaneous masses had a chalazion-like appearance. Histologically, the JXG masses were characterised by Touton giant cells with inflammatory cells. Additionally, there was no significant difference in treatment modalities between the two groups (P = 0.072), and 24 (75.0%) patients underwent surgical excision. The overall recurrence-free survival was 3.6 to 52.8 (median 27.0) months in the current patients. For published cases with available follow-up information, there was no recurrence in 10 cases and improvement in 1 case, with a median follow-up of 9.5 months. CONCLUSION: Solitary eyelid JXG is a rare clinical entity and should be included in the differential diagnosis of eyelid mass lesions in patients of all age groups. Surgical excision is often selected for efficient treatment and to obtain an excisional biopsy.

FEATURES OF DIAGNOSIS AND ADVERSE COURSE OF NEONATAL JUVENILE XANTHOGRANULOMA: CASE REPORT.

The work describes a case of rare neonatal systemic juvenile xanthogranuloma with an initial damage of the scalp, limbs, back and abdomen, multiple damages of the parenchyma of both lungs, spleen and liver with the development of a severe form of congenital cholestatic hepatitis. The diagnosis was established on the basis of histopathological and immunohistochemical examination of the skin nodules. The child on the background of therapy under the Langerhans cell histiocytosis III program achieved a partial response, which was manifested by a reduction of granulomatous formations on the skin, elimination of liver failure, but retained hepatosplenomegaly, specific lesions of the lung parenchyma, liver, and left kidney. Against the background of cytostatic therapy, the patient developed secondary pancytopenia, perianal ulcerative-necrotic dermatitis with lesions on buttocks, stomatitis, protein-energy deficiency, acute liver failure. coagulopathy, disseminated intravascular coagulation syndrome, acute renal failure, respiratory failure of III degree, cardiovascular insufficiency of III degree, pulmonary edema, cerebral edema, cerebral coma of II-III degree, enterocolitis, intestinal paresis. Despite multicomponent intensive care, the child's condition progressively deteriorated, and the patient died. The aspects of differential diagnosis of neonatal systemic juvenile xanthogranuloma are discussed.

Cutaneous histiocytoses in children.

Cutaneous histiocytoses constitute a heterogeneous group of diseases characterised by the cutaneous accumulation of cells with the cytological and phenotypic features of macrophages or dendritic cells. The clinical spectrum ranges from self-resolving, skin-limited conditions to severe, multiorgan disease with a high morbidity rate. Until recently, cutaneous histiocytoses were classified according to the immunophenotype of the pathological cells, with differentiation between Langerhans cell histiocytosis (LCH) [CD1a+, CD207 (langerin)+] and non-Langerhans cell histiocytosis (CD68+, CD163+, CD1a-, CD207-). Over the last 12 years, a number of new pathophysiological findings (in particular, molecular pathology results) regarding histiocytoses have contributed to a new classification based on molecular alterations, as well as on clinical and imaging characteristics and the phenotype. The most frequent entities in children are juvenile xanthogranuloma and LCH.

Pediatric liver failure with massive sinusoidal infiltration of histiocytes.

Histiocytic neoplasms, such as Langerhans cell histiocytosis (LCH) and disseminated juvenile xanthogranuloma (JXG), can involve the liver and sometimes cause liver failure. We aimed to classify non-LCH histiocytic proliferating disorders that do not exhibit typical disseminated JXG histology. We examined four pediatric patients who presented with liver failure and splenomegaly. Two patients with liver cirrhosis without cholestasis underwent liver transplantation (LT). The other two patients presented with giant cell hepatitis causing neonatal/infantile acute liver failure (ALF). The infantile ALF patient also underwent LT. Liver dysfunction developed after LT in all three transplant cases and the grafts exhibited massive sinusoidal infiltration of histiocytes with hemophagocytosis, similar to the native liver. The neonatal ALF patient was treated with an LCH-type chemotherapy regimen, and is alive and well at 18 months. Infiltrating histiocytes were positive for CD68 and CD163, and negative for CD1a, CD207, and S-100 protein. The BRAF V600E mutation was not present. Liver histological findings were not consistent with conventional disseminated JXG or LCH, although the histological findings in other organs overlapped those of well-known histiocytic neoplasms. The histological and immunohistochemical findings of infiltrating histiocytes suggest that these four cases constituted a disseminated JXG-like systemic disease.

Oral juvenile xanthogranuloma: An unusual presentation in an adult patient and a systematic analysis of published cases.

OBJECTIVE: The purpose of this study was to describe an unusual case of intraoral juvenile xanthogranuloma (JXG) and to perform a systematic review to investigate the available literature regarding oral JXGs. STUDY DESIGN: We present a new case of oral JXG arising in a 36-year-old Italian woman and conducted a systematic literature review in PubMed, Web of Science, and Scopus, according to the PRISMA guidelines. RESULTS: Our review of the English-language literature yielded 34 cases of oral JXG, which included our case report. CONCLUSIONS: JXG is a non-Langerhans cell histiocytosis. Oral JXG has been reported, but it is a rare manifestation. Because of the rarity of oral lesions and possible variations in the clinical and histologic presentation, the correct diagnosis can be challenging, requiring a careful clinical and histopathologic evaluation with adjuvant immunohistochemical studies.