Angiofollicular lymphoid hyperplasis (Castleman's tumor) resembling a pericardial cyst: differentiation by computerized tomography

The great mimickers: Castleman disease

Castleman disease (CD) was first described and most commonly occurs in the form of classic hyaline-vascular-type CD with hyperenhancing localized (unicentric) nonneoplastic lymphadenopathy. CD may affect any body region including unusual locations for isolated lymph node enlargement. This makes CD a great mimicker of more common benign and malignant masses in the neck, chest, abdomen, and pelvis. CD masses commonly raise the suspicion of lymphoma, paraganglioma, neuroendocrine tumor, metastatic adenopathy, solid parenchymal tumors, and infectious or inflammatory diseases. The less common plasma cell-type CD, mixed CD, and human herpes virus-8-associated CD (HHV8-CD) are more prone to lead to generalized (multicentric) adenopathy without the typical nodal hyperenhancement and are associated with B symptoms and hematologic and immunologic manifestations. The generalized forms of CD have a worse prognosis, which can approach that of malignancies. CD has multiple known associations with neoplasms, skin diseases, blood dyscrasias, and immunodeficiency, which include certain forms of lymphoma; paraneoplastic pemphigus; polyneuropathy, organomegaly, endocrinopathy, M protein, and skin changes syndrome; and plasma cell dyscrasias. Cytokine overproduction (IL-6) is an important pathogenetic factor in the development of CD. The treatment is accordingly variable, from curative or diagnostic resection of a solitary lesion to systemic chemotherapy or anti-IL-6 therapy.

Castleman disease

Castleman and Towne described a disease presenting as a mediastinal mass resembling thymoma. It is also known as "giant lymph node hyperplasia", "lymph node hamartoma", "angiofollicular mediastinal lymph node hyperplasia", and "angiomatous lymphoid hyperplasia". The pathogenesis is unknown, but the bulk of evidence points toward faulty immune regulation, resulting in excessive B-lymphocyte and plasma-cell proliferation in lymphatic tissue. In addition to the mediastinal presentation, extrathoracic involvement in the neck, axilla, mesentery, pelvis, pancreas, adrenal gland, and retroperitoneum also have been described. There are 2 major pathologic variations of Castleman disease: (1) hyaline-vascular variant, the most frequent, characterized by small hyaline-vascular follicles and capillary proliferation; and (2) the plasma-cell variant, in which large lymphoid follicles are separated by sheets of plasma cells. The hyaline-vascular cases usually are largely asymptomatic, whereas the less common plasma-cell variant may present with fever, anemia, weight loss, and night sweats, along with polyclonal hypergamma-globulinemia. Castleman disease is a rare lymphoproliferative disorders. Few cases have been described world widely. In this article we reviewed the classification, pathogenesis, pathology, radiological features and up to date treatment with special emphasis on the role of viral stimulation, recent therapeutic modalities and the HIV-associated disease.

Castleman disease: the great mimic

Castleman disease is a nonclonal lymphoproliferative disorder and one of the more common causes of nonneoplastic lymphadenopathy. Because of its diverse manifestations and ability to affect any body region, Castleman disease is a great mimic of both benign and malignant abnormalities in the neck, chest, abdomen, and pelvis. Castleman disease most commonly manifests as unicentric disease (unicentric Castleman disease) with a hyperenhancing lymph nodal mass and should be considered in the differential diagnosis of lymphoma, metastatic adenopathy, and infectious and/or inflammatory diseases that result in adenopathy. Castleman disease includes a spectrum of pathologic variants, including the classic hyaline vascular type, the less common plasma cell variant of Castleman disease, and the more recently described multicentric Castleman disease and Castleman disease associated with human herpesvirus 8. Castleman disease has been associated with the human immunodeficiency virus, lymphoma, POEMS (polyneuropathy, organomegaly, endocrinopathy, M protein, and skin changes) syndrome, paraneoplastic pemphigus, and plasma cell dyscrasias. Aggressive forms of Castleman disease with systemic manifestations may occur. Unicentric hyaline vascular Castleman disease is often curable with surgery; however, multicentric Castleman disease may require steroid treatment, chemotherapy, antiviral medication, or the use of antiproliferative regimens because a surgical procedure cannot be curative in this setting. Supplemental material available at http://radiographics.rsna.org/lookup/suppl/doi:10.1148/rg.316115502/-/DC1.

Imaging features of atypical thoracic Castleman disease

The imaging features of 16 cases of pathologically proven atypical thoracic Castleman disease (CD) were retrospectively reviewed. Thirteen out of 16 tumors originated from atypical locations, including eight from the pleura and one each from the axilla, supraclavicular fossa, intercostal space, pericardium, and lung. Six out of 16 tumors revealed atypical enhancement, including poor CT enhancement in three tumors, target-like CT enhancement in two tumors, and concentric MR enhancement pattern in one tumor. These atypical enhancement patterns were histopathologically corresponded to various degrees of degeneration, necrosis, and fibrosis.

Paracardiac pleural Castleman disease: radiographic and MR findings

Castleman disease is a rare benign lymphoid tumour of uncertain aetiology that usually appears as a solitary mediastinal mass. We report a rare case of Castleman disease in the right paracardiac pleural space, occurring in a young woman with non-specific chest discomfort. MRI showed a well-defined, oval mass that was slightly hyperintense on T(1) weighted images, inhomogeneously hyperintense on T(2) and enhanced T(1) weighted images. The patient underwent radical tumour resection and has remained well for 8 years.

Castleman disease of the pleura: experience with eight surgically proven cases

BACKGROUND

Castleman disease of the pleura is unusual, and we present our experience with eight surgically proven cases.

METHODS

Between 1980 and 2002, 8 patients (7 women and 1 man; age range, 20 to 53 years; mean, 26.5 years) with surgically proven, pleural Castleman disease (six hyaline vascular type, one plasma cell type, and one mixed type) were encountered. Their clinical, imaging, and surgical findings were reviewed.

RESULTS

Five patients were asymptomatic, 1 had dyspnea, 1 had cough, and 1 experienced chest discomfort. Chest radiography showed a well-circumscribed interlobar, cardiophrenic, or paraaortic mass in 6 patients, a massive effusion in 1, and a focal diaphragmatic bulge in 1. Six tumors showed varying degrees of contrast enhancement (10 to 95 HU; mean, 46 HU) on computed tomography. Three cases appeared as well-defined, heterogeneously hyperintense pleural masses on magnetic resonance imaging. The masses varied in size from 3 to 10 cm (mean, 5.2 cm). Five masses greater than 5 cm had prominent pleural arterial blood supply and severe adhesions requiring thoracotomy and resection of nearby structures for radical tumor excision. Blood loss from patients varied between 100 and 850 mL (mean, 620 mL). No tumor recurrence was noted during follow-up (range, 1 to 16 years; mean, 6.5 years).

CONCLUSIONS

Pleural Castleman disease predominately affects young women and manifests as a well-circumscribed mass with a varying degree of contrast enhancement on computed tomography and heterogeneity on magnetic resonance imaging. Tumors greater than 5 cm have profuse pleural blood supplies and severe adhesion necessitating open thoracotomy and resection of neighboring structures. Radical resection can produce a satisfactory outcome.

Primary cysts and neoplasms of the mediastinum: recent changes in clinical presentation, methods of diagnosis, management, and results

Major changes have recently occurred in the clinical presentation, diagnosis, and management of primary lesions of the mediastinum. New diagnostic techniques and improved therapy have led to more objective preoperative diagnoses as well as better long-term results. These features are clearly demonstrated in a series of 400 consecutive patients with primary lesions of the mediastinum seen at Duke University Medical Center. Of these, 99 (25%) had a primary cystic lesion. The primary tumors included thymic neoplasms (17%), neurogenic tumors (14%), lymphoma (16%), germ cell tumors (11%), and a miscellaneous group. Malignant neoplasms were present in 166 patients (42%). The anterosuperior mediastinum was the most commonly involved site of a primary cyst or neoplasm (54%), followed by the posterior mediastinum (26%) and the middle mediastinum (20%). Symptoms were present in 62% of the patients and included chest pain (30%), dyspnea (16%), fever and chills (20%), and cough (16%). Of the lesions found on routine chest roentgenograms, 83% were benign. In contrast, 57% of the lesions in symptomatic patients were malignant. Prior to 1967, 94% of asymptomatic lesions were benign, but this figure has now decreased to 76%. Fifty percent of symptomatic patients had a malignant neoplasm before 1967 compared with 62% after that year. Newer diagnostic techniques have greatly enhanced the accuracy of the preoperative diagnosis. They include radioisotopic scanning, monoclonal antibodies, hormonal assay, electron microscopy, fine-needle aspiration biopsy, computed tomographic scans, and magnetic resonance imaging. Each has a definite role and is specifically illustrated as being quite important in this series.(ABSTRACT TRUNCATED AT 250 WORDS)