Renal cell carcinoma presenting as AA amyloidosis: a case report and review of the literature

Abstract

A 47-year-old Caucasian man developed mild diarrhoea associated with more than 10 kg weight loss, severe fatigue and anaemia. Endoscopy demonstrated deposits of AA amyloid within the gastrointestinal tract. He had heavy proteinuria with a serum albumin of 15 g/L consistent with systemic AA amyloidosis. He had no symptoms to suggest an underlying chronic inflammatory condition but had CRP 130 mg/L and SAA 474 mg/L. In an attempt to identify the source of his inflammatory response, he underwent a contrast-enhanced whole-body computed tomography scan, which revealed a necrotising mass lesion in the right kidney consistent with a renal cell carcinoma. It also showed non-mechanical obstruction of the small bowel and, immediately post-imaging, the patient developed intractable vomiting followed by oliguric renal failure requiring haemodialysis. Despite his renal and gut failure, he underwent right radical nephrectomy without further complications. Histology showed complete resection of a clear cell renal cell carcinoma and renal amyloid deposits. Post-surgery, his acute-phase response decreased to normal, consistent with the renal cell carcinoma acting as the inflammatory stimulus. Although he remains dialysis dependent, his gut function improved and he has regained both normal weight and serum albumin. Our case demonstrates partial resolution of AA amyloidosis with removal of the inflammatory source.

Nephrotic syndrome in a patient with metastatic melanoma: beyond the obvious

“…Although there is data demonstrating that serum amyloid A (SAA) protein is intensively expressed by malignant melanoma cells and could be a marker for predicting a high risk of tumor progression 18 , AA amyloidosis is an unusual complication of melanoma. A successful treatment of the underlying process can lead to the stabilization or improvement of renal function, reduction in protein excretion, and partial resolution of amyloid deposits 19 . Cancer cells are known to produce SAA protein 20 although AA amyloidosis is rarely associated with solid organ malignancies, metastatic disease and Hodgkin's lymphoma (< 7%) 21,22 .…”

Malabsorption Syndrome due to Intestinal Amyloidosis as Presentation of Renal Cell Carcinoma

“…AA amyloidosis is a paraneoplastic syndrome rarely associated with RCC (3–8% of cases) although several autopsies have suggested that RCC is the solid malignancy that most often causes AA amyloidosis, accounting for 25–42% of cases of solid tumors with secondary amyloidosis [ 1 , 6 , 8 , 16 ]. It is characterized by multisystem extracellular deposition of amyloid fibrils derived from cleavage fragments of the N -terminal portion of serum amyloid protein A [ 7 , 17 ].…”

“…The first association between amyloidosis and renal cell carcinoma was described by Ask-Up-mark in 1940 [ 8 ]. We found in the literature 19 cases of AA amyloidosis secondary to RCC [ 6 ]. Amyloid deposits are documented in the kidney, gastrointestinal tract, retroperitoneum, liver, spleen, adrenal glands, conjunctiva, and upper respiratory tract mucosa.…”

“…It appears as a complication of chronic inflammatory diseases such as rheumatoid arthritis and inflammatory bowel disease, chronic infections such as tuberculosis or syphilis, and tumors. As a paraneoplastic syndrome, AA amyloidosis has been described secondarily to renal cell carcinoma, non-Hodgkin's lymphoma, and, less frequently, bladder tumors and gastrointestinal stromal tumors [ 5 , 6 ].…”

Rapid clinical improvement of amyloid A amyloidosis following treatment with tocilizumab despite persisting amyloid deposition: a case report

“…Some cases of AA amyloidosis caused by renal cell carcinoma have been reported [ 8 – 10 ]; in such cases, improvement in amyloidosis was achieved after removal of the carcinoma. However, levels of CRP, an acute-phase protein used as a tumor marker of renal cell carcinoma, did not change in our patient and proteinuria increased after nephrectomy.…”