Tumor carcinoide atípico solitario de timo: una entidad inusual que no debemos olvidar / Solitary atipic carcinoid tumor of the thymus: an unusual entity that we should not forget

Resumen: Los tumores neuroendocrinos primarios (NET) del mediastino son muy raros. Presentamos el caso de un tumor carcinoide atípico primario de timo. Un hombre de 52 años que fue a un examen médico porque se quejaba de tos no productiva sin hemoptisis. Se solicitó una radiografía de tórax donde se evidenció un mediastino notablemente ensanchado, con una tomografía de tórax que mostro una masa tumoral de 90 x 50 mm en el mediastino anterosuperior que comprime el arco aórtico y la arteria pulmonar sin un plano de clivaje adecuado. Debido a que el tumor era infiltrativo, se proporcionó escisión quirúrgica completa, quimioterapia y radioterapia al mediastino. El objetivo principal de nuestro estudio fue evaluar los hallazgos de CT y MRI con relación a la literatura mundial.

Abstract: Primary neuroendocrine tumors (NET) of the mediastinum are very rare. We present the case of a primary atypical carcinoid tumor of the thymus. A 52-year-old man who went to a medical examination because he complained of a non-productive cough without hemoptysis. A chest radiograph was requested where a markedly widened mediastinum was evidenced, with a thoracic tomography showing a tumor mass of 90 x 50 mm in the anterosuperior mediastinum that compresses the aortic arch and pulmonary artery without an adequate cleavage plane. Because the tumor was infiltrative, complete surgical excision, chemotherapy and radiotherapy were provided to the mediastinum. The main objective of our study was to evaluate the findings of CT and MRI in relation to universal literature.

Endobronchial ultrasound-guided transbronchial needle aspiration combined with either endoscopic ultrasound-guided fine-needle aspiration or endoscopic ultrasound using the EBUS scope-guided fine-needle aspiration for diagnosing and staging mediastinal diseases: a systematic review and meta-analysis

The present systematic review and meta-analysis aimed to evaluate the available evidence base on endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) combined with either endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) or endoscopic ultrasound using the EBUS scope-guided fine-needle aspiration (EUS-B-FNA) for diagnosing and staging mediastinal diseases. PubMed, Web of Science, and Embase were searched to identify suitable studies up to June 30, 2019. Two investigators independently reviewed articles and extracted relevant data. Data were pooled using random effect models to calculate diagnostic indices that included sensitivity and specificity. Summary receiver operating characteristic (SROC) curves were used to summarize the overall test performance. Data pooled from up to 16 eligible studies (including 10 studies of 963 patients about EBUS-TBNA with EUS-FNA and six studies of 815 patients with EUS-B-FNA) indicated that combining EBUS-TBNA with EUS-FNA was associated with slightly better diagnostic accuracy than combining it with EUS-B-FNA, in terms of sensitivity (0.87, 95%CI 0.83 to 0.90 vs. 0.84, 95%CI 0.80 to 0.88), specificity (1.00, 95%CI 0.99 to 1.00 vs. 0.96, 95%CI 0.93 to 0.97), diagnostic odds ratio (413.39, 95%CI 179.99 to 949.48 vs. 256.38, 95%CI 45.48 to 1445.32), and area under the SROC curve (0.99, 95%CI 0.97 to 1.00 vs. 0.97, 95%CI 0.92 to 1.00). The current evidence suggests that the combination of EBUS-TBNA with either EUS-FNA or EUS-B-FNA provides relatively high accuracy for diagnosing mediastinal diseases. The combination with EUS-FNA may be slightly better.

Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) in diagnosis of mediastinal lesions / Punção aspirativa por agulha guiada por ultrassom endobrônquico (EBUS-TBNA) no diagnóstico de lesões do mediastino

ABSTRACT Objective To describe the results of endobronchial ultrasound-guided transbronchial needle aspiration in making diagnosis of mediastinal injuries associated to different causes. Methods A retrospective cross-sectional study of patients submitted to Endobronchial ultrasound-guided transbronchial needle aspiration at a private organization, between June 2013 and October 2016. All cases referred for collection of lymph nodes or peritracheal/peribronchial masses by endobronchial ultrasound-guided transbronchial needle aspiration, and evaluated through tomography or PET-CT were included. Interventional pulmonologists and thoracic surgeons with experience in the method did the procedures. Rapid on-site evaluation of fine needle aspiration was performed by an experienced pathologist. Material analysis included cytological smear and cytopathological analysis of paraffin-embedded cell blocks. Other specific analyses (immunocytochemistry, tests and cultures of infectious agents) were performed whenever necessary. Results We included 72 patients; 6 were excluded for presenting endobronchial lesions in which bronchoscopic biopsy could be performed, or intrathoracic lesions that were not accessible by endobronchial ultrasound-guided transbronchial needle aspiration. The mean age of 66 patients included for analysis was 61.17 years (±14.67 years), with a predominance of males (64%). Endobronchial ultrasound-guided transbronchial needle aspiration was definitive for diagnosis in 60 cases (91%). Three cases (4.5%) had inconclusive test results. There were no major complications related to the procedure. Conclusion Endobronchial ultrasound-guided transbronchial needle aspiration had a high diagnosis yield, with minimal morbidity, being an excellent option for diagnostic approach of patients with lymphadenopathy or intrathoracic lesions, and for neoplasm staging.

RESUMO Objetivo Descrever os resultados da utilização de punção aspirativa por agulha guiada por ultrassom endobrônquico na definição do diagnóstico em casos de lesões mediastinais por diferentes causas. Métodos Estudo transversal retrospectivo de pacientes submetidos à punção aspirativa por agulha guiada por ultrassom endobrônquico em instituição privada, entre junho de 2013 e outubro de 2016. Foram incluídos todos os casos referenciados para coleta de materiais de linfonodos ou massas peritraqueais/peribrônquicas por punção aspirativa por agulha guiada por ultrassom endobrônquico, estudados com tomografia ou PET-CT. Os procedimentos foram realizados por pneumologistas intervencionistas e cirurgiões torácicos com experiência no método. Rapid on-site evaluation da punção aspirativa por agulha fina foi realizada por patologista experiente. A análise do material incluiu citologia dos esfregaços em lâminas e análise citopatológica do emblocado celular. Outras análises específicas (imunocitoquímica, pesquisas e culturas de agentes infecciosos) foram realizadas se necessárias. Resultados Foram incluídos 72 pacientes; destes, 6 foram excluídos por apresentarem lesões endobrônquicas passíveis de biópsia broncoscópica convencional ou lesões intratorácicas não acessíveis a punção aspirativa por agulha guiada por ultrassom endobrônquico. Assim, a média de idade dos 66 pacientes incluídos para análise foi 61,17 anos (±14,67 anos), com predomínio do sexo masculino (64%). A punção aspirativa por agulha guiada por ultrassom endobrônquico foi definitivo para o diagnóstico em 60 casos (91%). Três casos (4,5%) foram inconclusivos. Não houve complicações maiores relacionadas ao procedimento. Conclusão A punção aspirativa por agulha guiada por ultrassom endobrônquico teve elevado rendimento diagnóstico, com mínima morbidade, constituindo excelente opção na abordagem diagnóstica de pacientes com linfadenopatia ou lesões intratorácicas e no estadiamento de neoplasias.

Protocolos de encaminhamento da Atenção Básica para a Atenção Especializada: cirurgia torácica e pneumologia / Routing protocols of primary care to specialized care: thoracic surgery and pulmonology

Este material tem como objetivo orientar as equipes que atuam na AB, qualificando o processo de referenciamento de usuários para outros serviços especializados. É uma ferramenta, ao mesmo tempo, de gestão e de cuidado, pois tanto guiam as decisões dos profissionais solicitantes quanto se constitui como referência que modula as avaliações apresentadas pelos médicos reguladores.

Improving CT-guided transthoracic biopsy of mediastinal lesions by diffusion-weighted magnetic resonance imaging

OBJECTIVES: To evaluate the preliminary results obtained using diffusion-weighted magnetic resonance imaging and the apparent diffusion coefficient for planning computed tomography-guided biopsies of selected mediastinal lesions. METHODS: Eight patients with mediastinal lesions suspicious for malignancy were referred for computed tomography-guided biopsy. Diffusion-weighted magnetic resonance imaging and apparent diffusion coefficient measurement were performed to assist in biopsy planning with diffusion/computed tomography fused images. We selected mediastinal lesions that could provide discordant diagnoses depending on the biopsy site, including large heterogeneous masses, lesions associated with lung atelectasis or consolidation, lesions involving large mediastinal vessels and lesions for which the results of biopsy using other methods and histopathological examination were divergent from the clinical and radiological suspicion. RESULTS: In all cases, the biopsy needle was successfully directed to areas of higher signal intensity on diffusion-weighted sequences and the lowest apparent diffusion coefficient within the lesion (mean, 0.8 [range, 0.6-1.1]×10-3 mm2/s), suggesting high cellularity. All biopsies provided adequate material for specific histopathological diagnoses of four lymphomas, two sarcomas and two thymomas. CONCLUSION: Functional imaging tools, such as diffusion-weighted imaging and the apparent diffusion coefficient, are promising for implementation in noninvasive and imaging-guided procedures. However, additional studies are needed to confirm that mediastinal biopsy can be improved with these techniques. .

Síncope como forma de presentación de masa mediastínica / Syncope in the debut of a mediastinal mass

El síncope supone el 3 por ciento de las consultas en los servicios deurgencias. En pediatría es frecuente, especialmente en niñas adolescentes de entre 15 y 19 años, quienes hasta un 25 por ciento hansufrido un episodio sincopal. La mayoría de las causas son benignas, pero el objetivo en la evaluación inicial de un paciente con síncope es descartar aquellas que supongan compromiso vital; una enfermedad cardíaca puede debutar en forma de síncope en un 10-28 por ciento de los casos. La historia clínica detallada y una exploración física exhaustiva son suficientes en la mayoría de las situaciones para descartar patología orgánica. Presentamos el caso de un paciente con linfoma B difuso de células grandes localizado en el mediastino cuyo diagnóstico se realizó tras episodios sincopales de repetición.

Punção aspirativa guiada por ultrassom endobrônquico no diagnóstico e estadiamento de linfadenopatia mediastinal: experiência inicial no Brasil / Endobronchial ultrasound-guided transbronchial needle aspiration in the diagnosis and staging of mediastinal lymphadenopathy: initial experience in Brazil

OBJETIVO: Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA, punção aspirativa por agulha guiada por ultrassom endobrônquico) é um método novo em diagnóstico e estadiamento linfonodal mediastinal. O objetivo do estudo foi avaliar os resultados preliminares obtidos com EBUS-TBNA no diagnóstico de lesões e no estadiamento linfonodal mediastinal. MÉTODOS: Foram avaliados pacientes com tumores ou adenopatias mediastinais e com diagnóstico ou suspeita de câncer de pulmão. Os procedimentos foram realizados com os pacientes sob sedação ou anestesia geral. O material coletado foi preparado em lâminas fixadas em álcool absoluto para citologia e em formol para bloco de células. RESULTADOS: Foram incluídos 50 pacientes (30 do sexo masculino), com média de idade de 58,3 ± 13,5 anos. Foram realizadas 201 punções em 81 linfonodos ou massas mediastinais (média de 2,5 punções). O material obtido foi considerado adequado para análise citológica em 37 pacientes (74 por cento), dos quais 21 (57 por cento) foram diagnosticados com malignidade. Nos 16 pacientes remanescentes, 1 teve diagnóstico de tuberculose, 6 tiveram seguimento clínico, e 9 foram submetidos a investigação adicional (2 diagnosticados com neoplasia - resultados falso-negativos). O rendimento do exame foi maior nos procedimentos com objetivo diagnóstico, em pacientes com lesões em múltiplas estações, e nas punções da estação linfonodal subcarinal. Um paciente apresentou sangramento endobrônquico resolvido com medidas locais. Não houve mortalidade na série. CONCLUSÕES: Esta experiência preliminar confirmou que o EBUS-TBNA é procedimento seguro, e que o nosso rendimento diagnóstico, inferior ao da literatura, foi compatível com a curva de aprendizado do método.

OBJECTIVE: Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a new method for the diagnosis and staging of mediastinal lymph nodes. The objective of this study was to evaluate the preliminary results obtained with EBUS-TBNA in the diagnosis of lesions and mediastinal lymph node staging. METHODS: We evaluated patients with tumors or mediastinal adenopathy, diagnosed with or suspected of having lung cancer. The procedures were performed with the patients under sedation or under general anesthesia. Material was collected by EBUS-TBNA, after which it was prepared on slides, fixed in either absolute alcohol (for cytology) or formalin (for cell-block analysis). RESULTS: We included 50 patients (30 males). The mean age was 58.3 ± 13.5 years. We performed 201 biopsies of 81 lymph nodes or mediastinal masses (mean of 2.5 punctures/biopsy). The quantity of material was considered sufficient for cytology in 37 patients (74 percent), 21 (57 percent) of whom were thus diagnosed with malignancy. Of the remaining 16 patients, 1 was diagnosed with tuberculosis, 6 entered clinical follow-up, and 9 underwent further investigation (2 diagnosed with neoplasm-false-negative results). The yield was higher when the procedure was performed for diagnostic purposes, as well as being higher in patients with lesions in multiple stations and in biopsies involving the subcarinal lymph node station. One patient had endobronchial bleeding, which was resolved with local measures. There were no deaths among the patients evaluated. CONCLUSIONS: This preliminary experience shows that EBUS-TBNA is a safe procedure. Our diagnostic yield, although lower than that reported in the literature, was consistent with the learning curve for the method.

Nodal Stations and Diagnostic Performances of Endobronchial Ultrasound-Guided Transbronchial Needle Aspiration in Patients with Non-Small Cell Lung Cancer

There are no accurate data on the relationship between nodal station and diagnostic performance of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA). We evaluated the impact of nodal station and size on the diagnostic performance of EBUS-TBNA in patients with non-small cell lung cancer (NSCLC). Consecutive patients who underwent EBUS-TBNA of mediastinal or hilar lymph nodes for staging or diagnosis of NSCLC were included in this retrospective study. Between May 2009 and February 2010, EBUS-TBNA was performed in 373 mediastinal and hilar lymph nodes in 151 patients. The overall diagnostic sensitivity, specificity, accuracy and negative predictive value (NPV) of EBUS-TBNA were 91.6%, 98.6%, 93.8%, and 84.3%, respectively. NPV of the left side nodal group was significantly lower than those of the other groups (P = 0.047) and sensitivity of the left side nodal group tended to decrease (P = 0.096) compared with those of the other groups. Diagnostic sensitivity and NPV of 4L lymph node were 83.3% and 66.7%, respectively. However, diagnostic performances of EBUS-TBNA did not differ according to nodal size. Bronchoscopists should consider the impact of nodal stations on diagnostic performances of EBUS-TBNA.

Predictors of malignancy in EUS-guided FNA for mediastinal lymphadenopathy in patients without history of lung cancer

Mediastinal lymphadenopathy [ML] poses a great diagnostic challenge. To investigate the predictors of malignancy in endoscopic ultrasound [EUS]-guided fine-needle aspiration [FNA] of ML in patients without known lung cancer. Retrospective study. Tertiary referral center. One hundred eight patients without known lung cancer who underwent EUS guided-FNA for ML between 2000 and 2007. All subjects underwent EUS-guided FNA. Data was collected on patients' demographics, and lymph node [LN] characteristics. Diagnosis of LN malignancy was based on FNA findings and clinical follow-up. One hundred eight patients were analyzed; 58 [54%] were men and 87 [79%] were Caucasian. Mean age was 55 years. Prior malignancy was present in 48 [43%] patients. A total of 126 FNA samples from 126 distinct LNs were performed. Twenty-five [20%] LNs were positive for malignancy. Mean short and long-axis for LNs were 13 and 29 mms respectively. Round shape and sharp borders were found in 29 [15%] and 25 [22%] LNs, correspondingly. Independent predictors of a malignant FNA were: Prior cancer [OR 13.10; 95% CI 2.7-63.32; P = 0.001], short axis [OR 1.10; 95% CI 1.00-1.22; P = 0.041] and sharp LN borders [OR 5.47; 95% CI 1.01-29.51; P = 0.048]. Age, race, gender, long axis, round shape were not associated with cancer in our cohort. Limitations: Retrospective design and lack of surgical gold standard. Increased risk of malignancy was associated with prior history of cancer, larger LN short axis and presence of LN sharp borders. These predictors may help guide endoscopists perform FNA in malignant LNs, increasing the overall efficiency of EUS-FNA for ML

Mediastinal seroma post laparoscopic repair of type IV paraesophageal hernia

Laparoscopic repair of paraesophageal hernia is safe and feasible and can provide comparable results for patients with type IV paraesophageal hernia. We report a rare case of mediastinal seroma in an 80-year-old gentleman who had a giant type IV paraesophageal hernia and was eventually admitted to our hospital for elective laparoscopic repair and recovered very well after surgery with resolution of the atelectatic lungs and air-fluid collection in his chest

Mediastinite descendente necrosante: tratamento cirúrgico torácico minimamente invasivo / Descending necrotizing mediastinitis: minimally invasive thoracic surgical treatment

OBJETIVO: Relatar uma série de casos de pacientes com mediastinite descendente necrosante (MDN) tratados com cirurgia torácica minimamente invasiva. MÉTODOS: Relatamos os casos de três pacientes com MDN submetidos à desbridamento mediastinal através de cirurgia torácica videoassistida no Hospital São Paulo, São Paulo (SP), desde a sua admissão até o desfecho final. RESULTADOS: Os três pacientes apresentaram boa evolução pós-operatória, com tempo médio de internação de 16,7 dias. CONCLUSÕES: Concluímos que a videotoracoscopia é uma técnica efetiva para a drenagem mediastinal no tratamento da MDN, com os benefícios da cirurgia minimamente invasiva: menos dor pós-operatória, menor liberação de fatores inflamatórios, retorno precoce às atividades diárias e melhores resultados estéticos.

OBJECTIVE: To report a case series of patients with descending necrotizing mediastinitis (DNM) who were treated with minimally invasive thoracic surgery. METHODS: We report three cases of male patients with DNM who underwent mediastinal debridement by video-assisted thoracic surgery at the Hospital São Paulo, located in the city of São Paulo, Brazil, from admission to the final outcome. RESULTS: The postoperative evolution was favorable in all three cases. The mean length of hospital stay was 16.7 days. CONCLUSIONS: We conclude that video-assisted thoracoscopy is an effective technique for mediastinal drainage in the treatment of DNM, with the benefits common to minimally invasive surgery: less postoperative pain, lower production of inflammatory factors, earlier return to activities of daily living, and better aesthetic results.

The Clinical Feasibility of Using Non-Breath-Hold Real-Time MR-Echo Imaging for the Evaluation of Mediastinal and Chest Wall Tumor Invasion

OBJECTIVE: We wanted to determine the clinical feasibility of using non-breath-hold real-time MR-echo imaging for the evaluation of mediastinal and chest wall tumor invasion. MATERIALS AND METHODS: MR-echo imaging was prospectively applied to 45 structures in 22 patients who had non-small cell lung cancer when the tumor invasion was indeterminate on CT. The static MR imaging alone, and the static MR imaging combined with MR-echo examinations were analyzed. The surgical and pathological findings were compared with using the Wilcoxon-signed rank test and McNemar's test. RESULTS: The accuracy, sensitivity and specificity of the combined MR-echo examination and static MR imaging for determining the presence of invasion were 84%, 83% and 85%, respectively, for the first reading session and they were 87%, 83% and 87%, respectively, for the second reading session (there was substantial interobserver agreement, k = 0.74). For the static MR imaging alone, these values were 62%, 83% and 59%, respectively, for the first reader and they were 69%, 67% and 74%, respectively, for the second reader (there was moderate interobserver agreement, k = 0.49). The diagnostic confidence for tumor invasion was also higher for the combined MR-echo examination and static MR imaging than that for the static MR imaging alone (p < 0.05). CONCLUSION: The combined reading of a non-breath-hold real-time MR-echo examination and static MR imaging provides higher specificity and diagnostic confidence than those for the static MR imaging reading alone to determine the presence of mediastinal or chest wall tumor invasion when this was indeterminate on CT scanning.

Sarcoidose em cicatrizes prévias / Sarcoidosis on previous scar

A sarcoidose é uma doença sistêmica de etiologia desconhecida, com apresentação clínica variável, onde 30 a 50% dos pacientes são assintomáticos ao diagnóstico. Afeta a pele, pulmões, sistema linfático, fígado e olhos. Outras áreas menos frequentemente afetadas são falanges ósseas, miocárdio, sistema nervoso central, fígado, baço e parótidas. A pele está envolvida em 25 a 35% dos casos, com diferentes formas de apresentação das lesões cutâneas. Relata-se caso de paciente de 26 anos cuja manifestação inicial da sarcoidose foram nódulos cutâneos em cicatrizes prévias e em que na investigação adicional mostrou-se haver acometimento pulmonar e mediastinal.

Sarcoidosis is a systemic disorder of unknown etiology and variable clinical presentation, where 30-50% of patients are asymptomatic at diagnosis. It affects the skin, lungs, lymphatic system, liver, and eyes. Less frequently affected areas are bone phalanxes, myocardium, central nervous system, liver, spleen and parotids. The skin is involved in 25-35% of the cases with different forms of presentation of skin lesions. Here the authors report the case of a 26-year-oldwhose initial manifestation of sarcoidosis were skin nodules on previous scars and which further investigation showed affected lung and mediastinum.

Infected benign cystic terotoma of the mediastinum

A young man aged 22 years presented with shortness of breath, left sided chest pain, mild dry cough, peripheral cyanosis, fever and generalized weakness for three years. He was diagnosed as having a large infected cystic mediastinal mass with tricuspid regurgitation and severe pulmonary hypertension. On thoracotomy, one litre of pus was aspirated and tumour was excised and sent for histopathology. Biopsy report revealed benign cystic teratoma. This case is reported to highlight the management of a huge infected benign cystic teratoma which is rarely found

Castleman's disease in a 35 year-old woman with a giant mediastinal mass

The patient was a 35 year-old woman with a 10-month history of breathing difficulty, cough and chest pain. An anterior-posterior chest radiograph revealed opacification of the right hemithorax with reduced right lung volumes. As part of diagnostic evaluation, a computed tomography [CT] scan was performed which showed a huge mass in the right anterior mediastinum with extension to the right side of the pleural space. It was resected through postero-lateral thoracotomy. The patient was discharged in a good condition. The pathology report showed hyaline vascular variant of Castleman's disease

[Epidemiology of mediastinal masses during five years [1382-1387] in Ahvaz]

The most common tumors of mediastinum are neurogenic tumors, while mediastinal tumors are common in adolescent and middle ages. Lymphoma is a common cause of mediastinal tumors in children. We observed an increase in prevalence of lymphoma in adults. This study was to evaluate mediastinal masses over 5 years duration. The study was carried out over five years stated from 1382 [2003] in three surgery departments of Ahvaz University of Medical Sciences, Iran. Patients with mediastinal mass were evaluated for age, gender, signs and symptoms, chest X-ray, chest CT scan and the methods of removal and the pathological reports of results of tissue samples. Sixty patients were evaluated and there was no difference in gender. Mediastinal masses were most common in 3rd and 4th decades of life. Anterior mediastinum was the most common involved site. Anterior mediastinotomy was the most common operation from which large tissue samples were taken from 78.33% and 51.67% of the mediastinal masses were lymphoma. The best method to take large tissue of these tumors is anterior mediastinotomy. The most common pathology in mediastinal masses is lymphoma. Lymphoma must be suspected in young patients with fever, cough, dyspnea and a mediastinal mass

Doença de Castleman associada a derrame pleural / Castleman's disease accompanied by pleural effusion

A doença de Castleman é uma rara afecção do tecido linfóide. Relatamos o caso de uma paciente do sexo feminino com otosclerose bilateral, sem sintomas respiratórios e com achado incidental de derrame pleural esquerdo em uma radiografia de tórax. A tomografia computadorizada de tórax revelou uma massa mediastinal. A biópsia demonstrou tratar-se de variante plasmocitária da doença de Castleman. A paciente foi submetida à ressecção da massa mediastinal. Houve regressão do derrame, o qual persistiu como pequena loculação no espaço pleural esquerdo.

Castleman's disease is a rare disorder of the lymphoid tissue. We report the case of a female patient with bilateral otosclerosis, no respiratory symptoms, and pleural effusion discovered as an incidental finding on a chest X-ray. Computed tomography of the chest revealed a mediastinal mass. The biopsy findings demonstrated that it was a plasmacytic variant of Castleman's disease. The patient underwent mediastinal mass resection. This resulted in near-total resolution of the effusion, which remained as a small loculation within the left pleural space.

Langerhans cell histiocytosis of mediastinal node.

The predominant clinical and radiological features of Langerhans Cell Histiocytosis (LCH) in children are due to osseous involvement. Extra-osseous disease is far less common, occurring in association with bone disease or in isolation. In the present study, LCH was presumptively diagnosed on Ultrasound guided Fine needle aspiration cytology (FNAC) of the mediastinal lymph node in a 18 month-old child. The diagnosis was confirmed by histological examination of the biopsy material.S-100 protein localization in the LCH cells is often positive on immunohistochemistry.