Amyloidosis of the renal pelvis: a harbinger of mammary carcinoma?

Abstract

We describe a rare case of light chain immunoglobulin amyloid (AL) accumulation in the central and lower pole renal calyces. Our patient, a woman aged 60, presented with several episodes of gross haematuria. Radiological imaging detected a filling defect in the left renal pelvis. Rigid ureteroscopy showed a corresponding mucosal abnormality resembling transitional cell carcinoma. A definitive preoperative tissue diagnosis could not be reached. Laparoscopic-assisted left nephroureterectomy was indicated. Histopathological examination excluded malignancy, revealing congophilic deposits of submucosal amyloid. A constellation of findings confirmed localised or primary amyloidosis with an AL immunophenotype but no evidence of clonal B-cell disease in the amyloid-associated lymphoplasmacytic cell infiltrate. Investigation for systemic plasma cell dyscrasia and echocardiography and scintigraphy for visceral amyloid deposits were negative for systemic disease. At a follow-up period of 30 months, there is no recurrence. However, our patient was diagnosed with breast cancer 21 months ago.

Figure 1

Enhanced axial computer tomography urogram shows thickening of the mucosa in the left lower pole calyx (dashed red circle).

Figure 2

Video fluoroscopy showing abnormal mucosa in the lower pole calyces (dashed red circle).

Figure 3

Rigid ureteroscopy shows papillary excrescences resembling urothelial malignancy.

Figure 4

(A) Formalin-fixed nephroureterectomy specimen with granular haemorrhagic mucosa highlighted (dashed red ellipse). (B) Close up of highlighted region.

Figure 5

Tissue slice of abnormal pelvicalyceal mucosa.

Figure 6

Corresponding stained section of tissue slice from figure 5 (H&E ×2.5).

Figure 7

Photomicrograph showing massive submucosal amyloid deposits (H&E ×100).

Figure 8

Suburothelial amyloid (Congo red ×100).

Figure 9

Immunohistochemistry for light chain immunoglobulins (immunoperoxidase ×100).

Figure 10

Amyloid with numerous plasma cells and intermingled inflammatory infiltrate (CD138 ×100).

Figure 11

Polyclonal expression in bystander plasma cell population (A) κ, (B) λ (immunoperoxidase ×200).