Unicentric Castleman disease was misdiagnosed as pancreatic mass: A case report

Castleman's disease (CD) is a lymphatic proliferative disorder of unknown cause and is rarely seen clinically. It has been divided into unicentric and multicentric types. Unicentric CD (UCD) occurs as a solitary enlarged mass and mediastinal lymph nodes are the most common site. Surgical excision has proven to be curative for UCD. Multicentric CD (MCD) appears as a systemic disease with peripheral lymphadenopathy. MCD had a poor response to surgery and monoclonal antibodies with rituximab have become a research hotspot.

A 44-year-old woman presented with a pancreatic mass during routine physical examination. She had no obvious symptoms, such as fever, abdominal pain, abdominal distension, or jaundice. Ultrasound examination indicated a hypoechoic mass between the body of the pancreas, left lobe of the liver and stomach. It had a clear boundary, irregular shape, uneven echo, and no obvious blood flow signals. To clarify the diagnosis, contrast-enhanced ultrasound examination was performed, which showed a benign pancreatic lesion. Neuroendocrine or solid pseudopapillary tumor was a possible diagnosis. The patient underwent further contrast-enhanced computed tomography and contrast-enhanced magnetic resonance imaging, which were suggestive of solid pseudopapillary tumor or neuroendocrine tumor. All the examinations failed to give a definitive diagnosis, and the patient underwent surgery. The final pathological and immunohistochemical results showed that the mass was CD.

This case highlights when lymphadenopathy is encountered clinically, CD should be considered and a biopsy should be performed.