Castleman disease presenting as DOTATATE-positive retroperitoneal mass

Area of Science:

• Oncology
• Radiology
• Pathology

Background:

• Castleman disease is a rare lymphoproliferative disorder with variable presentations.
• Its imaging features can be mistaken for malignant neoplasms, complicating diagnosis.
• Diagnostic challenges arise when imaging findings suggest malignancy but are ultimately non-neoplastic.

Purpose of the Study:

• To report a case of hyaline-vascular Castleman disease presenting with imaging findings suggestive of metastatic neuroendocrine tumor.
• To highlight the potential for non-neuroendocrine pathologies to exhibit abnormal uptake on DOTATATE PET/CT.
• To emphasize the importance of considering Castleman disease in the differential diagnosis of DOTATATE-avid lesions.

Main Methods:

• Case presentation of a patient with intermittent hypertension, palpitations, and chest pain.
• Computed tomography (CT) imaging revealed a retroperitoneal mass near the adrenal gland.
• 68Ga-DOTATATE positron emission tomography-computed tomography (PET/CT) demonstrated uptake in the mass, lymph nodes, and bone lesions.

Main Results:

• Histopathological examination confirmed hyaline-vascular Castleman disease, not a neuroendocrine tumor.
• The patient's presentation and initial imaging were highly suggestive of a metastatic neuroendocrine tumor.
• DOTATATE PET/CT showed significant uptake in the Castleman disease mass and metastatic sites.

Conclusions:

• DOTATATE PET/CT, while sensitive for neuroendocrine tumors, can demonstrate uptake in non-neuroendocrine conditions like Castleman disease.
• Castleman disease should be included in the differential diagnosis for patients with DOTATATE-avid masses, especially when clinical and biochemical findings are atypical for neuroendocrine tumors.
• This case underscores the need for integrated interpretation of imaging, clinical, and pathological data for accurate diagnosis.