Idiopathic multilocular thymic cyst-an incidental anterior mediastinal mass

Acquired thymic cyst are multilocular and they occur de novo or in association with mediastinal neoplasm, systemic autoimmune diseases and trauma. Here, we report a case of acquired multilocular thymic cyst due to non-specific inflammatory etiology in a 42-year old gentleman and our approach to diagnosis and management of anterior mediastinal mass. With no specific clinical symptom, he was diagnosed with anterior mediastinal mass incidentally by imaging studies. Definitive diagnosis of multilocular thymic cyst was obtained by tissue diagnosis of the anterior mediastinal mass resected during the surgery.

Quantitative Thoracic Magnetic Resonance Criteria for the Differentiation of Cysts from Solid Masses in the Anterior Mediastinum

OBJECTIVE: To evaluate quantitative magnetic resonance imaging (MRI) parameters for differentiation of cysts from and solid masses in the anterior mediastinum. MATERIALS AND METHODS: The development dataset included 18 patients from two institutions with pathologically-proven cysts (n = 6) and solid masses (n = 12) in the anterior mediastinum. We measured the maximum diameter, normalized T1 and T2 signal intensity (nT1 and nT2), normalized apparent diffusion coefficient (nADC), and relative enhancement ratio (RER) of each lesion. RERs were obtained by non-rigid registration and subtraction of precontrast and postcontrast T1-weighted images. Differentiation criteria between cysts and solid masses were identified based on receiver operating characteristics analysis. For validation, two separate datasets were utilized: 15 patients with 8 cysts and 7 solid masses from another institution (validation dataset 1); and 11 patients with clinically diagnosed cysts stable for more than two years (validation dataset 2). Sensitivity and specificity were calculated from the validation datasets. RESULTS: nT2, nADC, and RER significantly differed between cysts and solid masses (p = 0.032, 0.013, and 0.63; nT2 > 0.39. In validation dataset 1, the sensitivity of the RER, nADC, and nT2 criteria was 87.5%, 100%, and 75.0%, and the specificity was 100%, 40.0%, and 57.4%, respectively. In validation dataset 2, the sensitivity of the RER, nADC, and nT2 criteria was 90.9%, 90.9%, and 72.7%, respectively. CONCLUSION: Quantitative MRI criteria using nT2, nADC, and particularly RER can assist differentiation of cysts from solid masses in the anterior mediastinum.

Cervicothoracic Thymic Cyst: An Unusual Presentation

Cervicothoracic thymic cysts are rare and difficult to diagnose preoperatively. We report a case of a cervicothoracic thymic cyst presenting as a lateral neck mass and mimicking a laryngocele in a 3-year-old boy and its definitive management.

Analysis of CT imaging findings and pathological features of the thymic cyst / 实用放射学杂志

Objective To analyze CT imaging findings and pathological features of the thymic cyst.Methods The CT findings of 20 cases with thymic cyst confirmed by pathology were analyzed retrospectively.The analysis included the location,shape ,size ,density ,contour, unilocular or multilocular,with or without walls,enhancement and lesion periphery.The pathology results were compared to CT findings.Results All lesions were located in the anterior mediastinum,in which the location of left side in 12 cases,right side in 6 cases,median mediastinum in 2 cases.All lesions had clear border and unilocular,including round shape in 4 cases,oval shape in 8 cases,and irregular shape in 8 cases with triangular shape in 1 case,the size range was 2-6 cm.4 cases had obvious cyst wall.The CT value of the cyst had range of 4-53 HU,with 10 cases less than 10 HU and 10 cases greater than 10 HU.There was no enhancement within the cysts of 20 cases and the cyst wall had enhancement in 4 cases.All cases of pathological findings were confirmed as thymus cyst.Gross sample showed gray red or isabeling.The lesion was cystic in 18 cases,soft stereocyst in 2 cases,bright yellow liquid within the capsule in 10 cases,butter fat in 5 cases,chylomicrons in 3 cases,unilocular in 19 cases and multilocular in 1 case (butter fat).Microscope showed the fibrous capsule wall in all cases,lined with squamous epithelium,ciliated columnar epithelium,monolayer columnar epithelium,in which could be seen normal thymus tissue.The thickness of the wall was no more than 0.5 cm,and multilocular wall smooth,no obvious inflammatory response in the surrounding.Conclusion CT image findings can clearly show the thymic cyst site,shape,size,density and boundaries,unilocular or multilocular,with or without walls.The CT image can reflect pathological features of the thymic cyst,and can provide accurate and reliable information for the clinic.

A Case of Ectopic Lateral Cervical Thymic Cyst Mimicking as a Second Branchial Cleft Cyst

Cervical thymic cysts are rare lesions of neck mass often misdiagnosed clinically as branchial cleft cyst and are mostly diagnosed, pathologically after surgery. The authors applied surgical resection to a 34-year-old man with right upper neck mass, which was misdiagnosed preoperatively as a second branchial cleft cyst. The pathological tissue examination result showed that the patient was diagnosed with a cervical thymic cyst. The thymic cyst of the lateral neck has not been reported from adult in Korean. Herein, we present the case with review of the related literature.

Spontaneous Thymic Cyst Hemorrhage Manifesting as a Mediastinal Mass / 대한내과학회지

Thymic cysts are uncommon benign lesions in the anterior mediastinum. We here describe a 55-year-old male with spontaneous thymic cyst hemorrhage manifesting as a rapidly enlarging mediastinal mass that was resected completely with video-assisted thoracoscopic surgery. To the best of our knowledge, this is the first report of a spontaneous thymic cyst hemorrhage in Korea. In cases of rapidly enlarging mediastinal masses, spontaneous thymic cyst hemorrhage should be considered as a differential diagnosis.

IMAGES: Ectopic thymic cyst: A rare case report.

Ectopic thymic tissue in the neck is rarely reported in medical literature. Being uncommon, they are rarely included in the clinical diagnosis of cervical cystic masses and are misdiagnosed by surgeons as branchial cysts, lymphatic malformations, epidermoid cysts, dermoid cysts or thyroglossal cysts, lymphadenitis or neoplastic masses. Although it is rare, cervical thymic cyst should be considered in the differential diagnosis of a lateral cystic neck mass. Here we report a rare case of thymic cyst in a young 15-year-old male child on the left side of the neck. Histopathology of the excised cyst revealed thymic tissue composed of prominent Hassall's corpuscles, cholesterol clefts, lymphoid aggregates and cyst lined by cuboidal and squamous cells.

Quistes tímicos, una patología infrecuente del mediastino / Thymic cysts, an unusual disease of the mediastinum

Los quistes tímicos representan el 1 - 5 por ciento de las masas del mediastino anterior. Por su relativa frecuencia, constituyen un grupo importante entre los quistes mediastínicos. Generalmente son asintomáticos, pero pueden presentarse con disnea, dolor torácico y tos. PRESENTACIÓN DE CASOS: Se presentan tres casos de quiste tímico en pacientes de género femenino de 54, 59 y 70 años. Todas refirieron historia de más de un año de evolución de síntomas como dolor torácico, tos, disnea y disfagia. Se estudiaron con radiografía y tomografía computada de tórax que demostró imagen de tumor mediastínico de aspecto quístico. Por tratarse de lesiones sintomáticas, en todas se realizó tratamiento quirúrgico. En el intraoperatorio se observaron quistes tímicos de gran tamaño, los cuales fueron resecados en su totalidad, sin incidentes. Estudio histopatológico concluyó quiste tímico en los tres casos. Las pacientes no presentaron complicaciones postoperatorias y en el seguimiento se encontraron asintomáticas. DISCUSIÓN: Los quistes del mediastino son lesiones poco comunes. Su origen histológico es variado. Se describen los quistes broncogénicos y tímicos como los más frecuentes, sin embargo, también se cuentan los de origen pleural, pericárdico y esofágico. En particular, los quistes tímicos generalmente se localizan en el mediastino anterior. Se describen los de origen congénito y los adquiridos, cada uno con características propias. El tratamiento quirúrgico es indicación en pacientes sintomáticos, y se considera un método seguro con baja morbilidad. El diagnóstico se confirma con la resección de la lesión y el estudio histopatológico...

Thymic cysts account for 1-5 percent of masses of anterior mediastinum. For its frequency, are described as an important group of mediastinal cysts. Usually are asymptomatic, but they may present as chest pain, dyspnea and cough. CASEREPORT: Three cases of thymic cyst in female patients of 54,59 and 70 years old are presented. All of three patients reported history of over a year of evolution with symptoms like chest pain, cough, dyspnea and dysphagia. They were studied with thorax radiography and with chest computed tomography which showed a mediastinal cystic tumor. Because they had symptomatic lesions, surgical treatment was performed. During surgery large thymic cysts were observed. The lesions were totally resected without incidents. Histopathological study concluded thymic cyst in all three cases. The patients did not have postoperative complications and were asymptomatic in the follow-up. DISCUSSION: Mediastinal cysts are uncommon lesions. Histological origin is varied. Bronchogenic and thymic cysts are most common, however, pleural, pericardic and esophagic cysts are also observed. Particularly, thymic cysts are often located in anterior mediastinum. Congenital or acquired origin are described, each one with specific characteristics. Surgical treatment is indicated in symptomatic patients, and is considered a safe approach with low morbidity. The diagnosis is confirmed with the surgical resection and histopathological study...

Micronodular Thymoma with Lymphoid Stroma in a Multilocular Thymic Cyst: A Case Study

Herein, we report a case of micronodular thymoma with lymphoid stroma in a previously healthy 73-year-old male. Thymectomy was performed. The solid and macrocystic masses were encapsulated with focal invasion. The solid portion consisted of nodules of bland-looking spindle or round epithelial cells in lymphoid stroma containing prominent germinal centers. The epithelial cells had moderate amount of cytoplasm and occasional mucin production. The cystic portion was lined with cuboidal epithelium. According to World Health Organization (WHO) classification, the mass was diagnosed as a micronodular thymoma with lymphoid stroma accompanied by a pre-existing multilocular thymic cyst. Micronodular thymoma with lymphoid stroma, a possible variant of type A thymoma, is an extremely rare tumor. This so-called "unusual" variant may imply the schematic weakness of the current WHO classification that cannot cover all morphologic types. Further study is recommended for clarification of this variant and its incorporation into the current classification.

Multilocular Thymic Cyst with Prominent Lymphoid Follicular Hyperplasia: A Case Report

We present herein an unusual case of multilocular thymic cyst, with prominent lymphoid follicular hyperplasia, in a 64-year-old man. It was incidentally founded as a mediastinal mass on chest radiography, during a routine health check-up. Computed tomography revealed a cystic lesion, which contains thick septa involving the thymus. The resected mass, 8x4 cm in diameter, involved the thymus and there is no adhesion or invasion into the adjacent tissue. The cut surface showed cystic spaces with thick white-tan firm wall, which cysts contained gelatinous material. Microscopically, the lesion was characterized by multiple cysts, lined by flattened cuboidal epithelium that was separated by thick walls, having a dense lymphoid tissue with lymphoid follicles. The patient was discharged without any complication and is well without evidence of recurrence for sixteen months.

Squamous Cell Carcinoma Arising in a Thymic Cyst : A Brief Case Report

We present here the case of a 73-year-old man with squamous cell carcinoma that arose in a thymic cyst, and this was incidentally found by chest radiography. Computed tomography revealed a 3.6 cm-sized predominantly cystic lesion with a mural nodule at the antero-superior mediastinum. The resected specimen was a well demarcated cystic mass with a solid mural nodule. Microscopically, the nodule was determined to be invasive squamous cell carcinoma that had originated from the benign squamous epithelium lining the thymic cyst.

A Case of SIADH Diagnosed by Repeated Water Load Tests in a Hyponatremic Patient with Radiologically Suspicious Thymoma / 대한신장학회지

The causes of hypo-osmolar hyponatremic patients without edema are mainly related to either SIADH (syndrome of inappropriate antidiuretic hormone secretion) or hypovolemia and the evaluation of extracelluar volume status can be a clue to differentiate between the two. As a diagnostic andtherapeutic tool, positive response to isotonic saline load test is recognized in favor of hypovolemic hyponatremia but there is a pitfall due to similar response in a subset of euvolemic hyponatremia, SIADH in case that combined with hypovolemia or accompanied by low sodium intake. In such case, water load test may provide more help for exact evaluation of hypovolemia and SIADH. Hereby, we report a case of a 74 year old patient with doubtful thymoma radiologically presented to emergency room with symptomatic severe hyponatremia (108 mEq/L) consistent with clinical and biochemical features of hypovolemia and positive response to initial isotonic saline infusion. However, episodes of hyponatremia recurred despite euvolemic status, which was diagnosed as SIADH by water load test. We initially considered thymoma as a cause of SIADH but its pathologic finding was a thymic cyst. And hyponatremia with hypovolemic feature recurred but the final diagnosis came out as idiopathic SIADH by repeated water load test. His hyponatremia was completely corrected by strict water restriction (<500 cc/day).

A Case of Thymic Cyst in the Middle Mediastinum Mimicking Pericardial Cyst

A thymic cyst in the middle mediastinum adjacent to the right pericardium is extremely rare. We report a case of a large thymic cyst in the right cardiophrenic angle, compressing the right atrium, which was presented as a cardiomegaly on the chest radiograph and a pericardial cyst on the echocardiography. The definitive diagnosis was confirmed using surgical resection and biopsy.

Two Cases of Ectopic Cervical Thymic Tumors Mimicking as Thyroid Tumors / 대한이비인후과학회지

The thymus arises from the ventral wings of the third and fourth branchial pouches in the embryo. Subsequently, the thymus passes down to the mediastinum by the sixth week of gestation. Several unusual conditions such as remnants of the thymus and incomplete descent may occur along the path of descent. Therefore, thymic diseases such as thymoma, thymic hyperplasia, and thymic cyst can be found in the neck. Thymoma is the most common anterior mediastinal mass in adult. Rarely, it is presented as an anterior neck mass, commonly located in the anterolateral aspect of the neck or adjacent to the thyroid. Cervical thymic cyst is uncommon and usually occurs in the first and second decades. Cervical thymic cyst after the third decade is so rare that it is very difficult to diagnose preoperatively. We experienced two cases of cervical thymic neoplasm in the lower anterior neck in an adult. Here, we present the cases with a review of the related literatures.

Thymic Cysts: Two cases report

Thymic cyst is relatively rare tumor which usually occurs in the neck or mediastinum. Cervical thymic cyst is usually situated laterally and deep to the anterior border of the sternocleidomastoid muscle, simulating a branchial cyst. Thymic cyst of the mediastinum is usually detected incidentally and differential diagnoses include cystic degeneration of thymoma, and cystic teratoma. Two case of a cervical and a mediastinal thymic cysts were reported. The one was a cervical thymic cyst developed slowly growing mass in a 53-year-old male a for 10 years. The cyst was unilocular and measures 5.4x2.9x2.8 cm with columnar or squamous cell linings. The other is a mediastinal thymic cyst developed in a 37-year-old female with chest discomfort for 7 months. The cyst was uniocular and measures 2.8x2.2x2.0 cm. The epithelial lining of the cyst was largely desquamated and covered by macrophages with cholesterol granuloma. Involutional thymic stissue in their walls were noted in both cysts. In both cases presence of thymic tissue in the wall of the cyst thought to be the most important diagnostic feature.