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Query: UMLS:C0019621 (Langerhans cell histiocytosis)
 3,250 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Eosinophilic granuloma is a well-recognized form of Langerhans cell histiocytosis, most commonly involving the skull bones, usually with an excellent prognosis. Recurrent and difficult to recognize osteolytic lesions of the skull are encountered only rarely. A patient with recurrent eosinophilic granuloma of the skull is reported. In spite of appropriate multimodality treatment, there were several recurrences, most recently with involvement of the mastoid process. Imaging studies revealed extensive involvement of surrounding structures with expansion of the tumor into the middle cranial fossa and slight pressure on the antero-medial portion of the temporal lobe of the brain. Despite extensive involvement, the patient had no complaints. Because of the rarity of such silent and unpredictable lesions, a systematic approach with regular CT and MRI follow-up is suggested.
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PMID:Unusual presentation of mastoid eosinophilic granuloma in a young patient. 1140 Jun 54

Benign intracranial hypertension is known to be associated with obesity, endocrine abnormalities, various medications, and cerebral venous sinus thrombosis. We report a patient presenting with headaches and vomiting attributed to benign intracranial hypertension. The diagnostic work-up revealed Langerhans' cell histiocytosis of the occipital bone. There was no evidence for cerebral vein thrombosis by cranial computed tomography scan, Doppler ultrasonography, planar and single photon emission computed tomography technetium 99m-labelled red blood cell scintigraphy, and magnetic resonance angiography. Excision of the occipital bone lesion and a short course of acetazolamide and prednisone were curative. We hypothesize that cytokines secreted by the tumor were responsible for the development of intracranial hypertension.
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PMID:Langerhans' cell histiocytosis presenting as intracranial hypertension. 1141 6

The ground-glass pattern is a common but nonspecific finding on CT. In certain clinical circumstances, it can suggest a specific diagnosis, indicate a potentially treatable disease, and guide a clinician to an appropriate area for biopsy. A pattern of centrilobular ground-glass nodules is fairly specific for the diagnosis of hypersensitivity pneumonitis with the appropriate clinical history. The tree-in-bud pattern indicates disease affecting the small airways. The differential diagnosis is lengthy; however, the most common process leading to this CT appearance is infection. Although commonly associated with M. tuberculosis, many infectious organisms can produce this pattern. When honeycombing is seen on HRCT, a confident diagnosis of lung fibrosis can be made. The most common causes of interlobular septal thickening on HRCT are pulmonary edema, pulmonary hemorrhage, and lymphangitic spread of cancer, and smooth thickening is characteristic of all three. Diffuse lung cysts in patients who are not immunocompromised generally signify Langerhans' cell histiocytosis, lymphangioleiomyomatosis, or centrilobular emphysema. Centrilobular emphysema can be diagnosed when the centrilobular artery is seen as a small nodular opacity in the center of the cyst. Langerhans' cell histiocytosis is often associated with parenchymal nodules, helping to distinguish it from lymphangioleiomyomatosis. When a nodular pattern is seen on HRCT, the differential diagnosis is very long, but can be narrowed by noting whether the nodules are random, centrilobular, or perilymphatic in distribution. A mosaic pattern of lung attenuation can represent an infiltrative, small airway, or vascular process. The distinction can often be made by noting the size of the pulmonary vessels in the abnormal areas of lung, and whether air trapping is present on expiratory scanning. Computed tomographic signs can be useful indicators of a specific disease process. For instance, the air bronchogram sign indicates that an opacity is intrapulmonary in location, and signals the possibility of two types of neoplasm: lymphoma and bronchioloalveolar cell carcinoma. An air crescent sign indicates recovery of the immune system in an immunocompromised patient with invasive pulmonary aspergillosis. The fallen lung sign is diagnostic of a bronchial transection in the correct clinical setting. The gloved finger sign is very suggestive of allergic bronchopulmonary aspergillosis. The halo sign is highly suggestive of early angioinvasive pulmonary aspergillosis in patients with acute leukemia. When a split pleura sign is seen, the diagnosis is often empyema, although other causes of pleuritis can lead to a similar CT appearance.
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PMID:CT signs and patterns of lung disease. 1169 64

Langerhans cell histiocytosis (LCH) is a disorder of unknown etiology that gives rise to clonal expansion of Langerhans-like cells or their precursors. The molecular basis include aberrant expression of several adhesion molecules and elevated expression of p53, c-myc, and H-ras. To identify new locations of LCH-related oncogenes or tumor-suppressor genes, we performed comparative genomic hybridization (CGH) and loss of heterozygosity (LOH) analysis on a series of 7 bone LCH lesions. Recurrent abnormalities were found by the CGH in all cases representing losses of DNA sequences on chromosomes 1p, 5, 6, 7, 9, 16, 17, and 22q. Gain of DNA copy number was seen on chromosomes 2q, 4q, and 12. The CGH data were supplemented by LOH analysis by means of 85 polymorphic microsatellite markers distributed along chromosomes 1, 7, 9, and 22. The highest frequency of LOH was found on 1p region in 3 of 7 informative cases and on chromosome 7 in 4 cases. Allelic loss was also detected on chromosomes 9 in 2 of 7 informative cases and on 22q in 1 of 7 cases. These results indicate that the deleted chromosomal segments may contain genes important in LCH initiation and progression.
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PMID:Detection of molecular cytogenetic aberrations in langerhans cell histiocytosis of bone. 1209 83

A benign bone lesion may have a typical appearance on plain radiographs. This is the case with benign cortical defects and osteochondroma. With most other lesions, cross-sectional imaging is needed to complete the study of the tumor. The nidus of osteoid osteoma is well demonstrated on computed tomography, but magnetic resonance imaging also will show the nidus in most cases. Magnetic resonance imaging is considered the modality of choice for evaluation of other benign musculoskeletal lesions because it is highly sensitive to changes in the signal intensity of bone marrow and adjacent soft tissues. It provides useful information for diagnosis of the lesion as in primary or secondary aneurysmal bone cyst, chondroblastoma, osteoblastoma, fibrous dysplasia, and osteofibrous dysplasia, and it helps differentiate these lesions from osteomyelitis, Langerhans' cell histiocytosis, and stress fracture. Bone scanning is most useful for depicting multiple silent lesions as may be seen in multiple osteochondromatosis, nonossifying fibromas, and polyostotic fibrous dysplasia.
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PMID:Magnetic resonance imaging of benign bone lesions: cysts and tumors. 1240 90

BACKGROUND The pathogenesis of Langerhans cell histiocytosis (LCH), a disease characterized by an abnormal accumulation of the dendritic Langerhans cells, is still unknown. Based on the monoclonality of the CD1a+ cell and reports of familial clustering, it is hypothesized that a genetic alteration at a cellular level may be causative. This genetic change may have an effect on the cellular mechanisms controlling proliferation and apoptosis. MATERIALS AND METHODS LCH-lesions were studied for the expression of Ki-67, present in the nucleus of proliferating cells. Furthermore, the expression of cell cycle-related gene products TGF-beta receptor I and II, MDM2, p53, p21, p16, Rb, and Bcl2 were studied. The TGF-betaR genes play a role in tumor suppression, whereas Bcl2 inhibits apoptosis. The remaining genes are part of either the p53-p21 and/or p16-Rb pathways, which induce cell cycle arrest or apoptosis in response to DNA damage. RESULTS In 30 biopsies the diagnosis of LCH could be confirmed on the basis of CD1a positivity (27 bone and 3 skin). All cases showed scattered nuclear-positive staining for the proliferation marker Ki-67. In more than 90% (n >/=27) of these cases, expression of TGFbeta receptor I and II, MDM2, p53, p21, p16, Rb, and Bcl2 was detected in lesional LCH cells. The overexpression was in general heterogeneous, ranging from limited focal staining of scattered cells within the lesion to strong diffuse staining. CONCLUSIONS These findings suggest that the cellular mechanisms that sense and respond to DNA-damage, namely the p53-p21 pathway and the p16-Rb pathway, are activated. The expression of Ki-67 indicates that the cells in LCH are proliferating. The observed overexpression of Bcl2 may play a role in the activation of p53 and p16 and/or the arrest of apoptosis.
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PMID:Expression of cell cycle-related gene products in Langerhans cell histiocytosis. 1246 13

Langerhans cell histiocytosis (LCH) is a rare neoplastic disease of specific dendritic cells which belong to the monocyte-macrophage system. The association of LCH with autoimmune disease is extremely rare and to our knowledge its coexistence with systemic lupus erythematosus (SLE) has not been described so far. We report a case of LCH affecting liver, spleen and abdomen lymph nodes, which developed in an adult female six years after diagnosis of SLE treated for a long time with prednisone. Histology showed infiltration of characteristic Langerhans cells with folded, grooved or lobulated nuclei with fine chromatin. In the background there were eosinophils, lymphocytes and CD-68-positive histiocytes. The neoplastic cells were S100p-immunopositive, but stained negatively for CD1a--probably as the result of overfixation of consulted material. CD-68 was present mostly in macrophages. Ultrastructurally, the tumour cells presented structures consistent with Birbeck granules. Clonal origin of neoplastic cells was shown using the HUMARA-PCR assay. The disease was refractory to treatment with high doses of prednisone and vincristine but complete response was achieved after treatment with caldribine combined with cyclophosphamide.
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PMID:Langerhans cell histiocytosis in a patient with systemic lupus erythematosus: a clonal disease responding to treatment with cladribine, and cyclophosphamide. 1248 6

There exists a rarely observed association between pulmonary histiocytosis X and bronchopulmonary cancer. However, the frequency of bronchopulmonary cancer in these patients is higher than in the general population. A 28-year-old patient who currently smokes ten packs of cigarettes a year came to our department of pneumology with complains of cough and hemoptysis. An x-ray of the thorax revealed bilateral cysts and a shadow in the upper part of the right pulmonary field. In addition, a chest tomography showed multiple cysts dispersed throughout the two pulmonary fields and an irregular mass with a diameter of four centimetres in the upper right lobe. Bronchopulmonary adenocarcinoma was diagnosed during a cytologic exam of the bronchial washing. We decided to perform a thoracotomy on the patient, since there was no far metastasis. An upper lobectomy and wedge resection of the upper segment of the lower right lobe, which had been invaded by the tumour, were performed. Histology confirmed the diagnosis of adenocarcinoma. A pulmonary biopsy was carried out on the tumour-free site and showed the presence of histiocytosis X. There is a hypothesis that a neoplasm developed on the pulmonary fibrosis could be an epiphenomenon of bronchopulmonary cancer in patients who smoke and have pulmonary histiocytosis X. It is interesting to note that histiocytosis X and bronchopulmonary cancer were diagnosed at the same time, since the bronchopulmonary cancer may have occurred within a few years following the diagnosis of histiocytosis X, even if she was a smoker. Hemoptysis, which is found in 5% of patients with histiocytosis X, may suggest cancer. This young patient, a smoker, who complained of hemoptysis, is a particularly rare case of the association between pulmonary histiocytosis X and bronchopulmonary cancer whose pathogenesis is not clear cut. It is thus important to note that smoking can have major consequences, even in young people.
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PMID:[Histiocytosis X and bronchopulmonary adenocarcinoma: a rare coexistence]. 1252 89

Prominent eosinophilic infiltrates are an unusual finding in the pancreas. Eosinophilic pancreatitis is one rare etiology of pancreatic eosinophilia, but other described causes of eosinophilic infiltrates have also included pancreatic allograft rejection, pancreatic pseudocyst, lymphoplasmacytic sclerosing pancreatitis (LPSP), inflammatory myofibroblastic tumor, and histiocytosis X. In this study we describe the clinicopathologic features of three new cases of eosinophilic pancreatitis and conduct a retrospective 18-year institutional review of the myriad disease processes associated with pancreatic eosinophilia. In the files of the Johns Hopkins Hospital, <1% of all pancreatic specimens had been noted to show increased numbers of eosinophils. Eosinophilic pancreatitis itself was a rare etiology for pancreatic eosinophilia, with only one in-house case over the 18-year study period and two additional referral cases. Other disease processes associated with prominent eosinophilic infiltrates were more common and included pancreatic allograft rejection (14 cases), LPSP (5 of 24 total LPSP cases evaluated), inflammatory myofibroblastic tumor (4 cases), and systemic mastocytosis (1 case). Patients with eosinophilic pancreatitis showed two distinct histologic patterns: 1) a diffuse periductal, acinar, and septal eosinophilic infiltrate with eosinophilic phlebitis and arteritis; and 2) localized intense eosinophilic infiltrates associated with pseudocyst formation. All three patients with eosinophilic pancreatitis had peripheral eosinophilia, and all had multiorgan involvement. One patient with LPSP also had marked peripheral eosinophilia, and 5 of 24 LPSP cases demonstrated prominent eosinophilic infiltrates in the gallbladder, biliary tree, and/or duodenum. Notably, not all of these patients with LPSP with prominent eosinophils in other organs had increased eosinophils in the pancreas itself. These results emphasize the infrequent nature of pancreatic eosinophilia and its multiple potential disease associations. True eosinophilic pancreatitis, although a fascinating clinicopathologic entity, is one of the rarest causes of pancreatic eosinophilia.
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PMID:Eosinophilic pancreatitis and increased eosinophils in the pancreas. 1260 89

Context.-We investigated expression of the adhesion molecule CD31 in sinus histiocytosis with massive lymphadenopathy (SHML) and Langerhans cell histiocytosis (LCH) because (1) SHML and LCH cells express a variety of cellular adhesion molecules and (2) SHML has been characterized as a reactive histiocytic proliferation, and tissue macrophages (histiocytes) are known to express CD31. Objective.-The purpose of this study was to determine whether SHML and LCH cells express CD31 and whether dual staining with CD31 and S100 facilitates diagnosis of these disease states. Methods.-Formalin-fixed, paraffin-embedded archival tissues were immunohistochemically stained via the labeled streptavidin-biotin method using antibodies against CD31 and S100 protein after heat-induced epitope retrieval. Archival tissues included SHML (n = 2), LCH (n = 10), malignant melanoma (n = 5), sinus hyperplasia (n = 4), granulomas (n = 4), granular cell tumor (n = 6), and normal skin (n = 4). Results.-Normal Langerhans cells in the epidermis were CD31(-)/S100(+); neoplastic Langerhans cells in LCH were CD31(+)/S100(+). Histiocytes in granulomas and in sinus hyperplasia were CD31(+)/S100(-); abnormal histiocytes in SHML were CD31(+)/S100(+). S100(+) tumors (malignant melanoma and granular cell tumor) were CD31(-). Conclusions.-The spectrum of cell types that express CD31 is expanded to include SHML and LCH. We speculate that up-regulation of CD31 in neoplastic Langerhans cells contributes to the migratory capability of LCH cells. CD31 may be a useful nonlysosomal marker of macrophages and their neoplastic counterparts (true histiocytic sarcomas). An immunohistochemical staining panel that includes CD31 and S100 facilitates the diagnosis of SHML and LCH.
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PMID:Sinus histiocytosis with massive lymphadenopathy and Langerhans cell histiocytosis express the cellular adhesion molecule CD31. 1265 80


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