Langerhans' cell histiocytosis of the liver in adults

[Isolated liver involvement in Langerhans cell histiocytosis: A case report]

Langerhans cell histiocytosis (LCH) is a disease whose physiopathology remains unclear, involving both inflammatory processes and clonal proliferation. It is observable at any given age, although about ten times more frequent in children than adults. Hepatic involvement is not rare, mostly part of a systemic disease, and linked to a poor prognosis. We report here a case of LCH with solitary hepatic involvement in a 74 year-old patient. This case demonstrated molecular anomaly of the MAPK pathway, BRAF N486_P490del. Through this observation, we precise the epidemiological and histological aspects and diagnostic criteria of this rare disease.

Imaging Phenotypes and Evolution of Hepatic Langerhans Cell Histiocytosis on CT/MRI: A Retrospective Study of Clinical Cases and Literature Review

(1) Background: pathological changes in hepatic Langerhans cell histiocytosis (LCH) have been observed; however, corresponding imaging findings can appear vague to physicians and radiologists. The present study aimed to comprehensively illustrate the imaging findings of hepatic LCH and to investigate the evolution of LCH-associated lesions. (2) Methods: LCH patients with liver involvement treated at our institution were retrospectively reviewed along with prior studies in PubMed. Initial and follow-up computed tomography (CT) and magnetic resonance imaging (MRI) were systematically reviewed, and three imaging phenotypes were created based on the lesion distribution pattern. Clinical features and prognoses were compared among the three phenotypes. Liver fibrosis was evaluated visually on T2-weighted imaging (T2WI) and diffusion-weighted imaging (DWI), and apparent diffusion coefficient (ADC) values of the fibrotic areas were measured. Descriptive statistics and a comparative analysis were used to analyze the data. (3) Results: based on the lesion distribution pattern on CT/MRI scans, patients with liver involvement were categorized as the disseminated lesion phenotype, scattered lesion phenotype, and central periportal lesion phenotype. Patients with scattered lesion phenotype were typically adults, and only a few of them had hepatomegaly (n_present = 1, 1/6, 16.7%) and liver biochemical abnormalities (n_present = 2, 2/6, 33.3%); patients with central periportal lesion phenotype were typically young children, and hepatomegaly and biochemical abnormalities were more apparent in these patients than those with another phenotype; and those with the disseminated lesion phenotype were found in all age groups, and the lesions evolved rapidly on medical imaging. Follow-up MRI scans show more details and can better document the evolution of lesions than CT. T2-hypointense fibrotic changes, including the periportal halo sign (n_present = 2, 2/9, 22.2%), patchy liver parenchyma changes (n_present = 6, 6/9, 66.7%), and giant hepatic nodules close to the central portal vein (n_present = 1, 1/9, 11.1%), were found, while fibrotic changes were not observed in patients with the scattered lesion phenotype. The mean ADC value for the area of liver fibrosis in each patient was lower than the optimal cutoff for significant fibrosis (METAVIR Fibrosis Stage ≥ 2) in a previous study that assessed liver fibrosis in chronic viral hepatitis. (4) Conclusions: The infiltrative lesions and liver fibrosis of hepatic LCH can be well characterized on MRI scans with DWI. The evolution of these lesions was well demonstrated on follow-up MRI scans.

Current perspectives on the role of liver transplantation for Langerhans cell histiocytosis: A narrative review

Langerhans cell histiocytosis (LCH) is a malignant disease of the histiocytes involving various organ systems. The spectrum of liver involvement in LCH ranges from mild transaminitis to end-stage liver disease. The hallmark of hepatic LCH is secondary sclerosing cholangitis, which manifests due to a progressive destruction of the biliary tree by malignant histiocytes. Chemotherapy remains the mainstay of treatment for active LCH. Early recognition, diagnosis and a systematic approach to the management of LCH can ameliorate the disease process. Nonetheless, the liver involvement in these patients may progress despite the LCH being in remission. Liver transplantation (LT) remains central in the management of such patients. Various facets of the management of LCH, especially those with liver involvement remain unclear. Furthermore, aspects of LT in LCH with regards to the indication, timing and post-LT management, including immunosuppression and adjuvant therapy, remain undefined. This review summarises the current evidence and discusses the practical aspects of the role of LT in the management of LCH.

International expert consensus recommendations for the diagnosis and treatment of Langerhans cell histiocytosis in adults

Langerhans cell histiocytosis (LCH) can affect children and adults with a wide variety of clinical manifestations, including unifocal, single-system multifocal, single-system pulmonary (smoking-associated), or multisystem disease. The existing paradigms in the management of LCH in adults are mostly derived from the pediatric literature. Over the last decade, the discovery of clonality and MAPK-ERK pathway mutations in most cases led to the recognition of LCH as a hematopoietic neoplasm, opening the doors for treatment with targeted therapies. These advances have necessitated an update of the existing recommendations for the diagnosis and treatment of LCH in adults. This document presents consensus recommendations that resulted from the discussions at the annual Histiocyte Society meeting in 2019, encompassing clinical features, classification, diagnostic criteria, treatment algorithm, and response assessment for adults with LCH. The recommendations favor the use of 18F-Fluorodeoxyglucose positron emission tomography-based imaging for staging and response assessment in the majority of cases. Most adults with unifocal disease may be cured by local therapies, while the first-line treatment for single-system pulmonary LCH remains smoking cessation. Among patients not amenable or unresponsive to these treatments and/or have multifocal and multisystem disease, systemic treatments are recommended. Preferred systemic treatments in adults with LCH include cladribine or cytarabine, with the emerging role of targeted (BRAF and MEK inhibitor) therapies. Despite documented responses to treatments, many patients struggle with a high symptom burden from pain, fatigue, and mood disorders that should be acknowledged and managed appropriately.

Hepatobiliary and Gastrointestinal Involvement in Langerhans Cell Histiocytosis-Spectrum of Three Cases

Langerhans cell histiocytosis (LCH) is a rare group of disorder, due to clonal neoplastic proliferation of dendritic cells in the bone marrow expressing a Langerhans cell phenotype. 1 This disease particularly affects the pediatric age group and young adults and often presents with skin rashes, lung infiltrates, and bone lesions. It can also manifest with endocrine dysfunction and hematopoietic disorders. Involvement of gastrointestinal tract is very rare. Herein, we present a spectrum of three cases with gastrointestinal involvement.

[Severe secondary sclerosing cholangitis as manifestation of a very rare underlying disease]

Langerhans cell histiocytosis (LCH) is a very rare cause of secondary sclerosing cholangitis. We report the case of a 42-year-old male patient with sclerosing cholangitis and histological evidence of LCH from a bile duct biopsy. Due to rapid disease progression and exhaustion of conservative therapeutic approaches the patient received a liver transplantation. Nearly 2 years after transplantation the patient has a good graft function and no signs of recurrence of the underlying LCH.

Liver Transplantation for Langerhans Cell Histiocytosis: A US Population-Based Analysis and Systematic Review of the Literature

Langerhans cell histiocytosis (LCH) is the most common histiocytic disorder. Liver involvement is seen in 10.1% to 19.8% of patients with LCH and can lead to secondary sclerosing cholangitis requiring liver transplantation (LT). We describe the characteristics and outcomes of patients undergoing LT for LCH. All patients undergoing a first LT for LCH in the United States were identified in the Scientific Registry of Transplant Recipients (SRTR) database (1987-2018). The Kaplan-Meier curve method and log-rank tests evaluated post-LT survival. A systematic literature review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) statement. A total of 60 LCH LT recipients were identified in the SRTR, and 55 patients (91.7%) were children with median total bilirubin levels at LT of 5.8 mg/dL (interquartile range [IQR], 2.7-12.9). A total of 49 patients (81.7%) underwent deceased donor LT (DDLT). The 1-year, 3-year, and 5-year patient survival rates were 86.6%, 82.4%, and 82.4%, respectively. The systematic review yielded 26 articles reporting on 50 patients. Of the patients, 41 were children (82.0%), 90.0% had multisystem LCH, and most patients underwent DDLT (91.9%; n = 34/37). Pre-LT chemotherapy was administered in 74.0% and steroids in 71.7% (n = 33/46) of the patients, and a recurrence of LCH to the liver was reported in 8.0% of the patients. Of the 50 patients, 11 (22.0%) died during a median follow-up of 25.2 months (IQR, 9.0-51.6), and the 1-year patient survival rate was 79.4%. LT can be considered as a feasible life-saving option for the management of liver failure secondary to LCH in well-selected patients.

Histiocytosis

Histiocytoses constitute a heterogeneous group of rare disorders, characterised by infiltration of almost any organ by myeloid cells with diverse macrophage or dendritic cell phenotypes. Histiocytoses can start at any age. Diagnosis is based on histology in combination with appropriate clinical and radiological findings. The low incidence and broad spectrum of clinical manifestations often leads to diagnostic delay, especially for adults. In most cases, biopsy specimens infiltrated by histiocytes have somatic mutations in genes activating the MAP kinase cell-signalling pathway. These mutations might also be present in blood cells and haematopoietic progenitors of patients with multisystem disease. A comprehensive range of investigations and molecular typing are essential to accurately predict prognosis, which can vary from spontaneous resolution to life-threatening disseminated disease. Targeted therapies with BRAF or MEK inhibitors have revolutionised salvage treatment. However, the type and duration of treatment are still debated, and the prevention of neurological sequelae remains a crucial issue.

High prevalence of BRAFV600E in patients with cholestasis, sclerosing cholangitis or liver fibrosis secondary to Langerhans cell histiocytosis

Targeted therapies with MAPK inhibitors have proven to modulate the clinical manifestations of patients with Langerhans cell histiocytosis (LCH). We explored the presence of BRAF^V600E mutation in our cohort of patients with LCH and cholestasis, sclerosing cholangitis, or liver fibrosis that presented resistance to chemotherapy. The BRAF^V600E mutation was detected either in the diagnosis (skin and bone) or liver biopsy in our cohort of 13 patients. Thus, we observed a high incidence of BRAF^V600E mutation in 100% either in diagnostic biopsy (skin and bone) or liver biopsy in patients with progressive liver disease, sequela, or liver transplant requirement.

Hepatic Langerhans cell histiocytosis: A review

Hepatic Langerhans cell histiocytosis (LCH) is characterized by proliferation and accumulation of Langerhans cells in the liver, causing liver dysfunction or forming a mass lesion. The liver can be involved in isolation, or be affected along with other organs. A common clinical hepatic presentation is cholestasis with pruritis, fatigue and direct hyperbilirubinemia. In late stages, there may be hypoalbuminemia. Liver biopsy may be required for the diagnosis of hepatic LCH. Histologic finding may be diverse, including lobular Langerhans cell infiltrate with mixed inflammatory background, primary biliary cholangitis-like pattern, sclerosing cholangitis-like pattern, and even cirrhosis at later stages. Because of its non-specific injury patterns with broad differential diagnosis, establishing a diagnosis of hepatic LCH can be challenging. Hepatic LCH can easily be missed unless this diagnosis is considered at the time of biopsy interpretation. A definitive diagnosis relies on positive staining with CD1a and S100 antigen. Liver involvement is a high risk feature in LCH. The overall prognosis of hepatic LCH is poor. Treating at an early stage may improve the outcome. Systemic chemotherapy is the mainstay of treatment and liver transplantation may be offered. New molecular markers involved in pathogenesis of LCH are being explored with a potential for targeted therapy. However, further studies are needed to improve outcome.

Findings encountered in percutaneous cholangiography in a case of post-transplant recurrence of hepatic Langerhans cell histiocytosis with biliary involvement

This case report describes a four-year-old boy who presented with the diagnosis of LCH with liver involvement. This required a living-related liver transplant one year later. The primary disease recurred in the transplanted liver 6 months post-transplant and led to progressive biliary dilatation. A percutaneous trans-hepatic cholangiogram was performed five years after transplant, showing a pattern of multifocal biliary duct strictures mimicking the pattern of primary sclerosing cholangitis and a stenosis of the biliary-enteric anastomosis. Despite management with an internal-external biliary drain, the stenosis of the biliary-enteric anastomosis evolved to an occlusion one year after drain removal. This was associated with progression of the changes in the biliary tree, this time associated with significant saccular dilatations secondary to the multiple areas of stenosis. Due to these findings and progressive deterioration of the function of the graft, the patient required re-transplantation. This report illustrates the findings in imaging of the biliary tree secondary to the recurrence of LCH after liver transplantation, which may help to recognize this complication to physicians facing a similar clinical scenario.

Muscle Infiltrative Adult Multisystem Langerhans Cell Histiocytosis Detected on Fluorodeoxyglucose Positron Emission Tomography/ Computed Tomography - A Rare Case

Langerhans cell histiocytosis (LCH) is a disease of unknown pathogenesis characterized by the accumulation of Langerhans cells which show immunopositivity for S-100 and CD1a. LCH with skeletal muscle involvement has been rarely described in literature. ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) is an important tool in identifying the sites of involvement in LCH. We present a rare case of muscle invasive LCH where ¹⁸F-FDG PET/CT showed involvement of multiple other sites such as the liver, bones, bone marrow, and possibly the thyroid gland in our case. Further, the current case also shows that liver involvement by LCH (possibly fibrotic phase) can be negative on PET but show lesions on CT.

Multisystem involvement Langerhans cell histiocytosis in an adult: A case report

BACKGROUND

Langerhans cell histiocytosis (LCH) is a rare condition wherein Langerhans cells proliferate abnormally, adversely impacting organs including lymph nodes, bones, skin, lungs, and pituitary gland. The LCH disease course varies widely among patients from a self-limiting condition to one that progresses rapidly and culminates in death. It is uncommon for multisystem LCH to be observed in adults. Herein we describe a woman suffering from multi-system LCH involvement.

CASE SUMMARY

A 37-year old Chinese woman was admitted to the hospital in June 2019 suffering from dyspnea that had progressed over the course of 5 years. Her medical history included: central diabetes insipidus (DI) that had been treated via radiotherapy, desmopressin acetate, and bromocriptine; bilateral pneumothorax with two surgeries having been performed to remove bullae; and autoimmune hepatitis that had been unsuccessfully treated using a combination of methylprednisolone and mycophenolate mofetil. A chest computed tomography (CT) scan revealed the presence of multiple pulmonary cysts of varying sizes. We re-analyzed right pulmonary bullae samples that had been removed in 2014, performed a systematic ¹⁸F-FDG PET/CT analysis, and convened a multidisciplinary medical team to diagnose and treat this patient. As a result, we were able to eventually diagnose this patient with LCH that was not associated with BRAF-V600E mutations.

CONCLUSION

We hope to emphasize the importance of systemic evaluation and of cooperation between multidisciplinary physicians with the goal of improving awareness and detection of this orphan disease.

Hepatic Langerhans Cell Histiocytosis (LCH) Presenting as a Harbinger of Multisystem LCH

Langerhans cell histiocytosis (LCH) is a rare systemic disorder characterized by an infiltration of CD1a+/langerin+ histiocytes, commonly involving bone, skin, and lymph nodes in children. Hepatic involvement is rarely observed in multisystem LCH. We describe an exceptional case of hepatic LCH in an adult preceding the diagnosis of multisystem LCH, mimicking anti-mitochondrial antibody (AMA)-negative primary biliary cholangitis (PBC). A 65-year-old man presented with intermittent pruritus, weakness, dyspnea, fever, and chills that have been progressive for four years. Physical examination was unremarkable. Laboratory work revealed cholestatic biochemistry profile. Liver biopsy showed portal non-necrotizing granuloma encasing a damaged duct (florid duct lesion), and multifocal lobular Kupffer cell clusters, suggestive of PBC. Tests for autoimmune diseases including AMA were negative. Endoscopic retrograde cholangiopancreatography (ERCP) was negative for biliary obstruction. One month after the liver biopsy, he developed flaky, red, and burning rash on the right scalp, forehead, and epigastric skin. A skin biopsy at an outside institution revealed LCH. Subsequent re-examination of the liver biopsy showed that the histiocytes within the florid duct lesion were positive for CD1a and S-100. Concurrently, a small focus of LCH was noted in his gastric biopsy performed for gastritis symptoms. Hepatic LCH may mimic AMA-negative PBC histologically and clinically and may present as a harbinger of multisystem LCH. While rendering the diagnosis would be challenging without prior history of LCH and with focal involvement, awareness of such presentation and communication with clinical colleagues may be helpful.

Langerhans cell histiocytosis in children: History, classification, pathobiology, clinical manifestations, and prognosis

Langerhans cell histiocytosis (LCH) is an inflammatory neoplasia of myeloid precursor cells driven by mutations in the mitogen-activated protein kinase pathway. When disease involves the skin, LCH most commonly presents as a seborrheic dermatitis or eczematous eruption on the scalp and trunk. Evaluation for involvement of other organ systems is essential, because 9 of 10 patients presenting with cutaneous disease also have multisystem involvement. Clinical manifestations range from isolated disease with spontaneous resolution to life-threatening multisystem disease. Prognosis depends on involvement of risk organs (liver, spleen, and bone marrow) at diagnosis, particularly on presence of organ dysfunction, and response to initial therapy. Systemic treatment incorporating steroids and cytostatic drugs for at least one year has improved prognosis of multisystem LCH and represents the current standard of care.

Langerhans cell histiocytosis presenting as Crohn's disease: a case report

PURPOSE

We describe an exceptional case of Langerhans cell histiocytosis (LCH) that presented as Crohn's disease and primary sclerosing cholangitis.

METHODS

The patient's clinical, endoscopic, and histologic data from the Centre Hospitalier de l'Universite de Montreal were reviewed, as well as the literature on LCH involving the digestive tract and the liver, with a focus on the similarities with Crohn's disease and primary sclerosing cholangitis.

RESULTS

A 39 years-old man first presented with anal fissures and deep punctiform colonic ulcers. Histologic assessment of colon biopsies showed chronic active colitis, consistent with Crohn's disease. Mild cholestasis and endoscopic retrograde cholangiopancreatography (ERCP) showing multiple intra and extrahepatic biliary tract strictures also led to a diagnosis of sclerosing cholangitis. Perianal disease progressed despite conventional treatment with antibiotics and infliximab. Subsequent discovery of non-Langerhans cutaneous xanthogranulomas and panhypopituitarism raised the suspicion of LCH, and a second review of colon biopsies ultimately led to the diagnosis, with the identification of Langerhans cells depicting elongated, irregular nuclei with nuclear grooves as well as immunohistochemical reactivity for S100, CD1a and vimentin. BRAF V600E mutation was detected afterwards by DNA sequencing of a bile duct sample.

CONCLUSION

LCH may mimic inflammatory bowel disease (IBD) and must be suspected in the presence of other suggestive clinical signs, or when there is failure of conventional IBD treatment.

How I manage pulmonary Langerhans cell histiocytosis

Pulmonary Langerhans cell histiocytosis (PLCH) is a rare sporadic cystic lung disease of unknown aetiology that is characterised by the infiltration and destruction of the wall of distal bronchioles by CD1a⁺ Langerhans-like cells. In adults, PLCH is frequently isolated and affects young smokers of both sexes. Recent multicentre studies have led to the more standardised management of patients in clinical practice. Smoking cessation is essential and is occasionally the only suitable intervention. Serial lung function testing is important because a significant proportion of patients may experience an early decline in forced expiratory volume in 1 s and develop airflow obstruction. Cladribine was reported to dramatically improve progressive PLCH in some patients. Its efficacy and tolerance are currently being evaluated. Patients who complain of unexplained dyspnoea with decreased diffusing capacity of the lung for carbon monoxide should be screened for pulmonary hypertension by Doppler echocardiography, which must be confirmed by right heart catheterisation. Lung transplantation is a therapeutic option for patients with advanced PLCH.The identification of the BRAF^V600E mutation in approximately half of Langerhans cell histiocytosis lesions, including PLCH, and other mutations of the mitogen-activated protein kinase (MAPK) pathway in a subset of lesions has led to targeted treatments (BRAF and MEK (MAPK kinase) inhibitors). These treatments need to be rigorously evaluated because of their potentially severe side-effects.

A phase IIa study of afuresertib, an oral pan-AKT inhibitor, in patients with Langerhans cell histiocytosis

BACKGROUND

Langerhans cell histiocytosis (LCH) is a clonal neoplasm characterized by widely varied clinical presentations, including multisystem involvement and systemic inflammatory symptoms. The AKT pathway is relevant to survival and proliferation of dendritic cells, and is also often upregulated in hematopoietic malignancies. A clinical response in an adult patient with LCH participating in the first-in-human trial of afuresertib prompted this prospective trial.

PROCEDURE

The population in the current study included treatment-naïve (n = 7) and recurrent/refractory patients with LCH (n = 10), who received oral afuresertib (125 mg). The majority of patients were treated for > 24 weeks, with four patients receiving treatment for > 48 weeks.

RESULTS

Pharmacokinetic analysis showed similar exposures in previously reported patients with other hematologic malignancies. Primary drug-related toxicities included Grade 1/2 nausea, diarrhea, dyspepsia, and vomiting. Grade 3 toxicities included fatigue, diarrhea, and pain (one of each). Another severe adverse event involved soft tissue necrosis. The overall response rate in evaluable subjects was 33% in treatment-naïve patients and 28% in patients with recurrent/refractory disease, which did not meet the predefined Bayesian criteria for efficacy.

CONCLUSION

Afuresertib has clinical activity in some patients with newly diagnosed and advanced LCH.

Severe sclerosing cholangitis after Langerhans cell histiocytosis treated by liver transplantation: An adult case report

BACKGROUND

Langerhans cell histiocytosis (LCH) is a rare hematopoietic disorder of unknown pathogenesis. LCH diseases may occur in a single organ or multisystem organ. The patients with multisystem involvement usually have a poor prognosis. Liver involvement in multisystem LCH results in severe complications, such as obvious sclerosing cholangitis (SC) with jaundice.

METHODS

We reported a 31-year-old man developed severe SC due to multisystem LCH and was successfully treated by liver transplantation (LT). In addition, we firstly used tacrolimus and mycofenolate mofetil as immunosuppressants to treat LCH after LT.

RESULTS

We performed the immunosuppressants to deal with the LCH after LT, now the patient is currently well with normal liver function and no evidence of recurrence of LCH for 4 and a half years follow-up.

CONCLUSION

LT should be recommended as an effective treatment for these adults with severe SC due to multisystem LCH. Finally, using tacrolimus and mycofenolate mofetil as immunosuppressants to treat LCH might be favorable to prevent LCH recurrence.

[Adult Langerhans cell histiocytosis]

Langerhans cell histiocytosis (LCH) is a rare disease affecting both genders and can occur at any age. It often evolves through successive flares, and its severity varies from benign forms that don't require treatment to life threatening disease. Some patients have important functional impairment with psychological and social consequences and prolonged disability. LCH may affect only one organ, with uni- or multifocal involvement or be multisystem disease involving multiple organs. The organs most frequently involved are bones, lung, skin and the endocrinal system. Pulmonary LCH is strongly related to smoking. Some patients have mixed histocytosis combining LCH and other histiocytic disorders. The diagnosis relies on the histological study of tissues samples, and shows tissue infiltration with large cell with pale cytoplasm and reniform nucleus, staining for CD1a and Langerin (CD207) on immunohistochemistry. The BRAF^V600E mutation is observed in tissue samples in approximately half of patients and the activation of the RAS-RAF-MEK-ERK pathway has been shown to be constantly activated in LCH lesions, regardless the BRAF status. These findings represent an important forward step in the understanding of the physiopathology of the disease. Treatment must be adapted to the severity of the disease and goes from conservative observation to systemic chemotherapy. Therapies targeting the RAS-RAF-MEK-ERK pathway are promising treatments for progressive disease.

Extrathoracic investigation in adult patients with isolated pulmonary langerhans cell histiocytosis

BACKGROUND

An important objective on diagnosis of patients with Langerhans cell histiocytosis (LCH) is to determine the extent of disease. However, whether systematic extrathoracic investigation is needed in adult patients with clinically isolated pulmonary LCH (PLCH) has not been evaluated.

METHODS

In this prospective, multicentre study, 54 consecutive patients with newly diagnosed clinically isolated PLCH were systematically evaluated at inclusion by bone imaging and blood laboratory testing to search for subclinical extrapulmonary LCH involvement. The patients were followed over a 2-year period. At each visit, they were asked about the presence of extrapulmonary manifestations of LCH.

RESULTS

In the absence of bone symptoms, the skeletal X-ray survey results were normal for all but two patients who had a localised bone lesion consistent with possible LCH involvement, that remained unchanged over 2 years of follow-up. Whole-body bone scintigraphy did not add information to the plain radiography findings for the detection of asymptomatic bone involvement in isolated PLCH. Conversely, it showed nonspecific focal bone uptake in 18% of the patients, mainly corresponding to post-traumatic or degenerative abnormalities unrelated to LCH. Mild leucocytosis due to neutrophilia was observed in 22% of the patients and was not related to their smoking habits. Three patients had mild isolated lymphocytosis without haematological disease, whereas two patients had mild lymphopaenia. A mild inflammatory biological syndrome was observed in a minority of patients without infection or constitutional symptoms and was not associated with progressive disease. A substantial proportion (24.5%) of the patients had abnormal biological liver test results, including elevated liver enzymes and/or cholestasis, which were not linked to LCH involvement in this cohort.

CONCLUSIONS

Obtaining a thorough history and performing comprehensive physical examination are essential for staging patients diagnosed with PLCH. In the absence of symptoms or signs suggestive of extrapulmonary LCH involvement, the systematic performing of recommended bone imaging does not appear informative. Although the observed blood laboratory abnormalities were not specifically related to LCH, performing these tests in the diagnostic workup for PLCH is useful because some of these alterations may impact patient management.

TRIAL REGISTRATION

ClinicalTrials.gov: No. NCT01225601; URL: www.clinicaltrials.gov.

Adult langerhans cell histiocytosis with hepatic and pulmonary involvement

Langerhans cell histiocytosis (LCH) is a rare proliferative disorder of Langerhans cells of unknown etiology. It can involve multiple organ systems with different clinical presentation, which complicates the diagnosis. It can range from isolated to multisystem disease with different prognosis. Although common among children, liver involvement is relatively rare in adults and frequently overlooked. Natural history of liver LCH fits into two stages: an early stage with infiltration by histiocytes and a late stage with sclerosis of the biliary tree. Pulmonary findings are more common and include multiple nodules in different stages of cavitation, predominantly in the upper lobes. We present a case of adult LCH with pulmonary and biopsy proven liver involvement with resolution of the hepatic findings after treatment.

Hepatic involvement of Langerhans cell histiocytosis in children--imaging findings of computed tomography, magnetic resonance imaging and magnetic resonance cholangiopancreatography

BACKGROUND

Langerhans cell histiocytosis is a rare disease that occurs mainly in children, and hepatic involvement is generally a poor prognostic factor.

OBJECTIVE

To describe CT and MRI findings of hepatic involvement of Langerhans cell histiocytosis in children, especially the abnormal bile duct manifestation on magnetic resonance cholangiopancreatography (MRCP).

MATERIALS AND METHODS

Thirteen children (seven boys, six girls; mean age 28.9 months) were diagnosed with disseminated Langerhans cell histiocytosis. They underwent CT (n = 5) or MRI (n = 4), or CT and MRI examinations (n = 4) to evaluate the liver involvement.

RESULTS

Periportal abnormalities presented as band-like or nodular lesions on CT and MRI in all 13 children. The hepatic parenchymal lesions were found in the peripheral regions of the liver in seven children, including multiple nodules on MRI (n = 6), and cystic-like lesions on CT and MRI (n = 3). In 11 of the 13 children the dilatations of the bile ducts were observed on CT and MRI. Eight of the 13 children underwent MR cholangiopancreatography, which demonstrated stenoses or segmental stenoses with slight dilatation of the central bile ducts, including the common hepatic duct and its first-order branches. The peripheral bile ducts in these children showed segmental dilatations and stenoses.

CONCLUSION

Stenosis of the central bile ducts revealed by MR cholangiopancreatography was the most significant finding of liver involvement in Langerhans cell histiocytosis in children.

Pathology of the liver sinusoids

The hepatic sinusoids comprise a complex of vascular conduits to transport blood from the porta hepatis to the inferior vena cava through the liver. Under normal conditions, portal venous and hepatic artery pressures are equalized within the sinusoids, oxygen and nutrients from the systemic circulation are delivered to the parenchymal cells and differentially distributed throughout the liver acini, and proteins of liver derivation are carried into the cardiac/systemic circulation. Liver sinusoid structures are lined by endothelial cells unique to their location, and Kupffer cells. Multifunctional hepatic stellate cells and various immune active cells are localized within the space of Disse between the sinusoid and the adjacent hepatocytes. Flow within the sinusoids can be compromised by physical or pressure blockage in their lumina as well as obstructive processes within the space of Disse. The intimate relationship of the liver sinusoids to neighbouring hepatocytes is a significant factor affecting the health of hepatocytes, or transmission of the effects of injury within the sinusoidal space. Pathologists should recognize several patterns of injury involving the sinusoids and surrounding hepatocytes. In this review, injury, alterations and accumulations within the liver sinusoids are illustrated and discussed.