Castleman’s Disease of the Kidney Mimicking Renal Cell Carcinoma on FDG PET/CT

Colonic Castleman Disease on FDG PET/CT

ABSTRACT

Colonic Castleman disease is very rare. We report FDG PET/CT findings of colonic Castleman disease in a 72-year-old man. On FDG PET/CT, it presented as a colonic soft tissue mass with intense FDG uptake. The final pathology supported a diagnosis of Castleman disease, plasma cell variant. This case hints us, although rare, Castleman disease should be considered as a differential diagnosis when we notice a hypermetabolic colon mass on PET/CT.

Hypermetabolic Unicentric Castleman Disease of Kidney on FDG PET/CT

ABSTRACT

A 62-year-old man presented with a huge lesion of left kidney on ultrasound in a health examination 1 month ago. The mass showed hypervascularity on enhanced CT and intense FDG uptake on FDG PET/CT in the lower pole of kidney, which suggested renal malignancy. The histopathological result after surgical resection of the mass confirmed the diagnosis of Castleman disease, the hyaline vascular variant.

Castleman Disease of the Kidney in Computed Tomography Urography

BACKGROUND

Castleman disease (CD) of the kidney is extremely rare. In this study, we presented a case of CD of the left kidney and comprehensively described the findings of computed tomography urography.

CASE PRESENTATION

The case involved unusual imaging characteristics of the focal central cystic area.

CONCLUSION

The small and regular cyst-like structures and the hyperdense mass relative to the renal parenchyma in plain scans might help distinguish the CD of the kidney from other hypervascular tumors.

Adrenal Castleman Disease on 99mTc-HYNIC-TOC Scan and FDG PET/CT

Adrenal Castleman disease is very rare. We reported image findings of a right adrenal mass in a 75-year-old man on Tc-HYNIC-TOC scan and FDG PET/CT. There was obviously elevated Tc-HYNIC-TOC activity, but the intensity of FDG activity was remarkable. Pheochromocytoma was initially suspected. However, pathology from resected specimen showed adrenal Castleman disease.

Primary hyaline vascular Castleman disease of the kidney: case report and literature review

BACKGROUND

Castleman's disease (CD) is an uncommon type of benign proliferation of the lymphoid tissue, characterized by local or systemic lymphadenopathy that most frequently appears in the mediastinum; involvement of the kidney is uncommon, and proliferation originating from the kidney is extremely rare. Herein, we report a rare case of hyaline vascular Castleman's disease (HV-CD) in a 56-year-old male patient and discuss its morphological characteristics and differential diagnoses including mantle cell lymphoma (MCL), follicular lymphoma (FL), and nodal marginal zone lymphoma (NMZL).

CASE PRESENTATION

A right upper-middle renal mass was detected after physical examination in a 56-year-old man without any clinical symptoms and a previous partial resection of the right kidney. Microscopically, the lymphoid follicles were increased in number and had expanded mantle zones and atrophic germinal centers. Vascular proliferation and hyalinization in the interfollicular zones were observed. Immunohistochemical staining showed CD20-positive cells in the mantle zones; CD21 and CD35 were expressed in the dendritic cells, CD3 was positive in a small number of T cells, and CD38 and CD138 were positive in the plasma cells. Additionally, Ki-67 expression was positive in the follicle centers. In contrast, staining for Bcl-2 in the germinal centers and cyclin D1 were negative. The immunohistochemical analysis combined with the morphological results supported the diagnosis of HV-CD. The patient recovered well after surgery.

CONCLUSIONS

Primarily renal HV-CD without lymph node hyperplasia or clinical symptoms is extraordinarily rare and different from the multicentric-type CD (MCD) with kidney involvement. Therefore, it is extremely important to improve the awareness of this diagnosis. Attention should be paid to the difference between HV-CD and common lymph node reactive hyperplasia, MCL, FL, NMZL, and so on. To avoid misdiagnosis as a renal malignant tumor requiring radical resection, distinguishing these diseases is crucial.