Utility of 18F-FDG PET/CT in Assessment of Disease Extent and Response to Treatment in Xanthoma Disseminatum.

The clinical utility of 18F-FDG PET/CT is being increasingly recognized in histiocytic disorders. We report the case of a 23-y-old woman who presented with slowly progressive, yellowish-brown papules, plaques, and nodules over her face and flexures. Besides the multiple cutaneous lesions, lesions of the brain, stomach, gallbladder, and marrow were additionally revealed by baseline 18F-FDG PET/CT. Skin biopsy and the overall clinical picture were consistent with xanthoma disseminatum. Subsequent PET/CT after cladribine therapy revealed a decrease in the extent and metabolic activity of most lesions, suggestive of a favorable response. This case report highlights the potential role of 18F-FDG PET/CT in the accurate assessment of disease extent and posttreatment response in rare histiocytic disorders.

Paraneoplastic Multicentric Reticulohistiocytosis on 18F-FDG PET/CT Breast Carcinoma Follow-up.

ABSTRACT: We report the case of a 60-year-old woman who underwent 18F-FDG PET/CT to evaluate a metastatic breast carcinoma. Follow-up 18F-FDG PET/CT showed progressive disease with 18F-FDG increased in primary tumor, axillary lymph nodes, and pleural and bone diffuse metastases but also a concomitant uptake in multiples joints. The anatomopathological analysis from skin biopsy revealed a multicentric reticulohistiocytosis, considered paraneoplastic in the context. Second follow-up PET/CT after treatment showed a decrease of 18F-FDG uptake in previously affected joints, consistent with the symptoms evolution. 18F-FDG PET/CT could be helpful in the detection and the evaluation of such rare systemic disorder.

18F-FDG PET/CT in Xanthoma Disseminatum.

A 64-year-old woman who had yellowish orange-colored, sharp-edged, and flat skin plaques and back pain for about a year was referred for F-FDG PET/CT imaging and her bone marrow biopsy revealed 10% to 20% atypical plasma cells suggestive of monoclonal gammopathy. PET/CT showed linear F-FDG uptake on the surface of the skin on the neck, axillary, chest, inframammary, and inguinal regions. Punch biopsy revealed numerous histiocyte infiltrates with large vacuoles, xanthomized cytoplasm in the dermis, and midsection, and there are several Touton-type giant cells supporting the preliminary diagnosis of xanthoma disseminatum.

Osteoarticular lesion in xanthoma disseminatum treated with total hip arthroplasty: a case report.

INTRODUCTION: Xanthoma disseminatum is a very rare disease classified as a benign non-Langerhans cell histiocytosis, which is rarely associated with osteoarticular lesions. There is only a report of tumor abrasion during treatment of osteoarticular lesions of this disease, artificial joint replacement has not been reported. We describe a patient in whom bilateral total joint replacement was performed for disseminated xanthoma lesions of the hip joints. CASE PRESENTATION: A 34-year-old Japanese woman had a chief complaint of bilateral coxalgia. She had been diagnosed as having disseminated xanthoma. Radiographs showed numerous 5-mm radiolucent bands that resembled worm-eaten tracks in the lower part of the femoral heads adjacent to the joint surface. In addition, short tau inversion recovery imaging scans showed high-intensity areas from the femoral head to the neck in both femurs, suggesting bone marrow edema. Total hip arthroplasty was performed for hip arthrosis on both hip joints caused by disseminated xanthoma. Deflection of the implants was a concern from the early stages postoperatively, but both the imaging and clinical findings have been satisfactory for 4 years of follow-up. CONCLUSIONS: A very unusual hip joint lesion of xanthoma disseminatum was replaced with a total artificial joint replacement, and the course over 4 years was good. Our patient's course will continue to be followed carefully.

Multicentric reticulohistiocytosis: a case report.

BACKGROUND: Multicentric reticulohistiocytosis is a rare form of non-langerhans cell histiocytosis presenting with skin changes and erosive arthritis. Infiltration of histiocytes and multinucleated giant cells are typical histological findings and confirm the diagnosis. CASE PRESENTATION: This case report describes a newly diagnosed case of multicentric reticulohistiocytosis in a healthy 26-year-old female originally from the Philippines. Eruption of papules and nodules on the hands and pain in multiple joints were the main complaints at the initial presentation. Radiographical findings of erosions in the small hand and feet joints were impressive. Initial histological findings did not match the clinical image, although later the clinical diagnosis was supported by histological findings in additional biopsies. CONCLUSIONS: Although initial histological findings did not match the clinical image, additional biopsies were valuable to confirm the diagnosis.

The utility of FDG-PET/CT imaging in the evaluation of multicentric reticulohistiocytosis: A case report.

INTRODUCTION: Multicentric reticulohistiocytosis (MRH) is a rare histiocytic disorder that involves the skin, joints, and visceral organs. CASE PRESENTATION: We report a 67-year-old woman with MRH who presented with a 2-years history of polyarthralgia and skin nodules. Her symptoms were an inflammatory polyarthropathy with punched-out lesions of the distal interphalangeal (DIP) joints of both hands. Doppler ultrasonography of the hands showed large bone erosions with power Doppler signals in the DIP joints. F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) demonstrated increased FDG uptake in cutaneous papules surrounding the affected joints, suggesting an inflammatory process. There was no evidence of malignancy. Biopsy samples of skin nodules exhibited dermal infiltration with CD68-positive histiocytes and multinucleated giant cells. The patient was diagnosed with MRH and treated with combination therapy comprising a steroid (prednisolone), tacrolimus, methotrexate, and infliximab, which resulted in clinical improvement. Following infliximab treatment, there was a significant decrease in a bone resorption marker (tartrate-resistant acid phosphatase 5b: TRACP-5b), suggesting that tumor necrosis factor-α targeting therapy may inhibit osteoclast formation and resorption activity in patients with MRH. CONCLUSION: MRH is a progressive destructive arthritic condition, and early diagnostic and therapeutic strategies are necessary to improve the outcome. FDG-PET/CT and joint ultrasonography might be noninvasive imaging modalities that could help diagnose MRH.

CNS Erdheim-Chester Disease: A Challenge to Diagnose.

Erdheim-Chester disease (ECD) is a rare nonLangerhans cell histiocytosis. Although approximately 50% of cases eventually involve the central nervous system (CNS), the CNS has seldom been reported as the initial biopsy site. The diagnosis of CNS ECD can be challenging due to morphologic overlap with reactive histiocytic proliferation, Langerhans cell histiocytosis (LCH), and extranodal Rosai-Dorfman disease (RDD). We present 3 cases from our files that illustrate the protean manifestations of ECD. Case 1 was a 47-year-old man with ataxia, dysarthria, and intermittent ophthalmoplegia whose cerebellar biopsy had shown only profuse, nonspecific Rosenthal fiber-rich piloid gliosis; ECD was diagnosed only at autopsy. The gliosis and marked variations in histiocyte morphology in different anatomical sites added to the diagnostic challenge. Case 2 was a 67-year-old female with chronic progressive symptoms and a pontine lesion that had been considered to be CLIPPERS by neuroimaging. Identification of a BRAFV600E mutation allowed an ECD diagnosis and treatment with the specific BRAFV600E inhibitor vemurafenib, which resulted in a marked sustained clinical response. Case 3 was diagnosed as ECD after positive bone biopsy with typical foamy histiocytes. Six years later, there was massive dural involvement that showed RDD-like, BRAF-mutation-negative histiocytosis. These cases highlight the clinical and histologic overlap that can occur among these disorders.

Disseminated intracranial xanthoma disseminatum: a rare case report and review of literature.

BACKGROUND: Xanthoma disseminatum (XD) is a rare benign histiocytic proliferating disease of non-Langerhans cell origin, which is clinically mainly characterized by cutaneous or mucous lesions. Although XD is acknowledged of one systematic disease, involvement of the central nervous system is quite rare. CASE PRESENTATION: We presented one 34-year-old Chinese female with disseminated intracranial XD without cutaneous or oral mucosal papules and masses of the other organs. MR imaging displayed multiple heterogeneous masses with intense enhancement in the right frontal lobe, temporal lobe, corpus callosum, left cuneus, suprasellar region, and right cerebellum. Pathological examination showed a neoplastic lesion composed of plentiful epitheloid or spindle cells. The cell had pink cytoplasm of vacuolation and foam with deviated nucleus absent of atypia and mitosis. The histiocytic markers including CD163, CD11c, Mac387 and CD68 were positive, whereas S-100, CD1a, GFAP, CD21, CD23 and so on were negative immunohistochemically. CONCLUSIONS: Intracranial XD without systemic involvement was extremely rare, which was supposed to be considered in differential diagnosis with other neoplasms of histiocytic origin or gliomas.

18F-FDG PET/CT Findings in Multicentric Reticulohistiocytosis.

Multicentric reticulohistiocytosis is a rare systemic inflammatory disease of unknown etiology characterized by the infiltration of histiocytes and multinucleated giant cells into multiple systems. The definitive diagnosis depends on biopsy of the affected tissues. Here, we report the F-FDG PET/CT findings of a 62-year-old man with multicentric reticulohistiocytosis. Increased FDG uptake was observed in cutaneomucosal papules, surrounding tissues of many joints, multiple muscles, and lymph nodes.

[Erdheim-Chester disease and Rosai-Dorfman disease: Pathological, radiological and clinical features of adult non-Langerhans cell histiocytosis]. / Erdheim-Chester- und Rosai-Dorfman-Erkrankung : Klinisch-radiologisch-pathologische Diagnostik von Non-Langerhans-Zell-Histiozytosen des Erwachsenenalters.

Non-Langerhans cell histiocytoses (N-LCH) of adulthood are rare disorders with heterogeneous pathogenesis, morphology and clinical presentation. In this review two disorders are presented, which predominantly develop in extracutaneous sites in adults. Erdheim-Chester disease is a rare nonhereditary clonal disorder of lipid storing histiocytes most commonly presenting as osseous involvement of the long bones. Other organ manifestations include the central nervous system (CNS), the cardiovascular system, the retroperitoneum and kidneys and less commonly the skin and the lungs. Immunohistochemical staining reveals positivity for the macrophage markers CD163, CD68 and lysozyme but CD1a and langerin are negative, in contrast to Langerhans cell histiocytosis. Rosai-Dorfman disease is considered to be a reactive histiocytic proliferation occurring mainly in lymph nodes. Prominent sinuses filled with commonly multinucleated, S100-positive histiocytes with emperipolesis are a characteristic feature and develops particularly as extensive lymphadenopathy with massive sinus histiocytosis but can also occur extranodally. Painless bilateral cervical lymph node enlargement is the most common clinical presentation. This review summarizes the clinical, radiological and histopathological findings and discusses the recent molecular advances in these rare disorders.

Reticulohistiocytoma of the orbit.

Reticulohistiocytoma is a rare, benign histiocytic proliferation of the skin or soft tissue. While ocular involvement has been documented in the past, there have been no previously reported cases of reticulohistiocytoma of the orbit. In this report, the authors describe a reticulohistiocytoma of the orbit in a middle-aged woman.