Multiple juvenile xanthogranuloma.

Juvenile xanthogranuloma is the most frequent form of non-Langerhans cell histiocytosis in children. Clinically, it presents as well defined, yellowish papules that are typically located on the head, neck, upper trunk, and proximal region of the extremities. Although solitary lesions are the most common presentation, few cases of multiple juvenile xanthogranuloma have been described, more frequently associated with extracutaneous involvement. We report a 2-month-old girl with 22 cutaneous papules, clinically and histologically compatible with juvenile xanthogranulomas. Screening of visceral involvement was performed with no evidence of systemic disease. Identifying high-risk factors of systemic disease in patients with multiple juvenile xanthogranuloma is essential to perform an appropriate management of this entity.

Congenital isolated juvenile xanthogranuloma of the sole - a unique case report in a newborn.

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.

Congenital Juvenile Xanthogranuloma in the Perioral Region: A Case Image.

Juvenile xanthogranuloma (JXG) is the most common form of non-Langerhans cell histiocytosis in childhood. It often presents with cutaneous involvement and exhibits a predilection for the head and neck region. This article illustrates a case of congenital JXG in a 5-month-old boy, characterized by a solitary, well-circumscribed nodule above the left upper lip. Histopathologically, the lesion exhibited histiocytes with eosinophilic cytoplasm and Touton giant cells. Immunohistochemistry revealed histiocytes positive for CD68 and Factor XIIIa, while negative for S-100 protein. Clinicians should become familiar with the broad clinical spectrum of cutaneous JXG, particularly its congenital presentation, in order to ensure timely and accurate management.

Juvenile xanthogranuloma manifesting with LCH-associated neurodegenerative disease-like radiological findings.

Here, we describe two patients with juvenile xanthogranuloma (JXG) manifesting with Langerhans cell histiocytosis (LCH)-associated neurodegenerative disease (ND)-like radiological findings. One patient showed typical radiological abnormalities at onset, which worsened with progressing central nervous system symptoms 7 years after LCH-oriented chemotherapy. Another showed spontaneous regression of clinical symptoms, with a transient radiological change 1 year after salvage chemotherapy for recurrence of JXG. These data regarding JXG-associated ND will facilitate future investigation of the disease, as well as development of therapeutic interventions.

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.

Alectinib In the Treatment of Systemic Juvenile Xanthogranuloma of Infancy With ALK Translocation.

This observational case series examines the diagnosis and treatment of 2 patients with systemic juvenile xanthogranuloma treated with alectinib.

NTRK expression is common in xanthogranuloma and is associated with the solitary variant.

BACKGROUND: Previously identified mutually-exclusive driver genes in juvenile xanthogranuloma (JXG) and adult xanthogranuloma (AXG) include mutations in MAP kinase pathway genes such as MAP2K1, BRAF, ARAF, KRAS, NRAS, PIK3CD as well as fusions in BRAF and ALK, with a subset of cases with no identified driver yet. NTRK fusion has been identified in rare cases. METHODS: We identified two consecutive index cases of localized JXG or AXG with NTRK1 fusion by next-generation sequencing (NGS) and confirmed by pan-NTRK immunostain. We expanded the study to a total of 50 cases of JXG and AXG using screening by pan-NTRK immunostain. We confirmed the specificity of our approach with negative results in 5 cases of histiocytic neoplasia lacking an NTRK fusion by NGS and 14 cases of non-neoplastic histiocytic disease. RESULTS: We found 23 cases of JXG or AXG with overexpression of NTRK by immunostain, and these cases were restricted to localized disease (23 of 43 cases, 53.5%) rather than disseminated disease (zero of seven cases). CONCLUSIONS: NTRK expression is common in JXG or AXG and associated with localized rather than disseminated disease. We speculate that the potential importance of this in JXG and AXG has not been previously appreciated due to the tendency to focus sequencing studies on disseminated disease. We confirm the presence of an NTRK1 fusion in two positive cases by NGS, however, additional genetic studies are necessary to further explore this.

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.