The great mimic

Clinical History

A 67-year-old woman presented at the radiology department to undergo a mammography because she had palpable nodules in both breasts. Furthermore, she had a history of asthenia and weight loss in the previous 3 months. On physical examination, multiple lymph nodes in all areas and splenomegaly were palpated.

Imaging Findings

Mammography: Nodular images up to 3 cm, well-defined in both breasts, which extend from upper outer quadrants to the armpits (Fig. 1, 2).

Breast ultrasound: Solid hypoechoic nodules, some with star-shaped centre hyperechogenity (Fig. 3). Intense vascularization in Doppler (Fig. 4).

Thoracoabdominal CT: Mediastinal, abdominal and bilateral axillary lymphadenopathy (Fig. 5). Some of them had a hypodense centre. (Fig. 6). Bilateral pleural effusion and splenomegaly (Fig. 5a, 5c).

Considering that multiple well-defined nodules were present in both breasts, the first possibility was cysts or fibroadenomas. Nevertheless, clinical and ultrasound findings weren’t concordant, so other possibilities were lymph nodes or metastasis. Ultrasound and CT confirmed the possibility of lymph nodes in multiple areas. The patient had systemic symptoms, so we thought of lymphoma or other lymphoproliferative disorders such as Castleman’s disease.

Histopathology revealed that it was a hyaline vascular variant of Castleman’s disease (Fig. 7).

The patient was treated with combined chemotherapy (CHOP) presenting complete remission. (Fig. 8).

Discussion

Castleman’s disease is a nonclonal lymphoproliferative disorder that was described by Benjamin Castleman in 1956 [1]. This disease has diverse clinical-radiological manifestations and can affect any body region. For these reasons, it is called “the great mimic”. It can mimic both benign and malignant disorders in the neck, chest, abdomen and pelvis. Approximately 70% occur in the chest, 15% in the neck and 15% in the abdomen and pelvis [2].
Two classifications exist for this disease: morphologic and histopathogenetic.
Morphologic classification distinguishes between unicentric and multicentric Castleman's disease.
Histopathogenetic classification (more recent) distinguishes between hyaline vascular, plasm cell and mix variants [3]. Hyaline vascular Castleman's disease represents 90% of the cases, occurs in young adults (30-40 years of age), it uses to be unicentric (90%) and usually manifests an asymptomatic course. Plasm cell Castleman's disease represents 10% of the cases, occurs in older adults (more than 60 years of age), it uses to be multicentric (10%) and manifests symptomatic course with asthenia, hepatosplenomegaly etc.
It has been associated with HIV, POEMS, VHH 8, plasma cell dyscrasias [4] etc.
Treatment includes surgery (unicentric Castleman's disease) and steroid treatment/ chemotherapy (multicentric Castleman's disease).
The definitive diagnosis is histopathologic, however, complementary imaging tests may facilitate pre-biopsy diagnosis.
The main radiologic features include [5]: solitary noninvasive mass (50%), dominant infiltrative mass with lymphadenopathy (40%) (Fig. 9) and multiple adenopathy without dominant mass (10%).
Considering that this disease has diverse clinic and radiologic manifestations, it can mimic multiple diseases. For this reason, it is a classic in the differential diagnosis which includes a big variety of diseases among which lymphoma has a prominent position.
Therefore, we must know some typical radiologic keys that can make the pre-biopsy diagnosis and the therapeutic management easier.
In the case of unicentric Castleman's disease if a mass located in ganglionic chains, mass which mimics vascular malformations or lymphadenopathy with pathological-non pathological aspect are present we must think in Castleman's disease. Lymphadenopathy with pathological—non pathological aspect means a lymphadenopathy with cortical thickness, intense vascularization and hypodense/hyperechoic central area which sometimes has a star shape (Fig. 3, 4).
Due to the great similarity with lymphoma, in case of multicentric Castleman's disease it is more difficult to make the differential diagnosis before the biopsy.
In conclusion, Castleman's disease is the great mimic and the diagnosis requires histopathological confirmation, however, there are some radiological features which can make the pre-biopsy diagnosis easier, like in our case, where the ultrasound showed lymph nodes with the typical pathological—non pathological aspect.

Differential Diagnosis List

Final Diagnosis

Multicentric hyaline vascular Castleman’s disease.

URL:	https://www.eurorad.org/case/13752
DOI:	10.1594/EURORAD/CASE.13752
ISSN:	1563-4086