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

Systemic AA Amyloidosis Secondary to Metastatic Renal Cell Carcinoma in a Hemodialysis Patient with Intractable Diarrhea

We describe an autopsied case of systemic AA amyloidosis secondary to metastatic renal cell carcinoma presenting intractable diarrhea. Severe diarrhea was the major symptom for the diagnosis of AA amyloidosis. No renal symptoms which are common in AA amyloidosis secondary to renal cell carcinoma were shown because hemodialysis following bilateral nephrectomy had already been started 9 years before. Treatment against metastatic tumors as a solution of AA amyloidosis could not be performed because of bad performance status and the patient died 5 months after the diagnosis. Autopsy findings revealed that AA amyloid deposition was seen in multi-organs including the intestine. The metastatic tumors were histologically compatible as metastasis of renal cell carcinoma. There was no other cause of chronic inflammation such as inflammatory arthritis. We concluded that chronic inflammation provoked by the metastatic tumors of renal cell carcinoma was a major cause of systemic AA amyloidosis. Intestinal AA amyloidosis with malabsorption was the cause of death. Clinicians should keep it in mind that solid organ malignancy can be a cause of AA amyloidosis and renal cell carcinoma is the most common carcinomatous cause. This case is particularly instructive in that progression of amyloidosis may be missed in hemodialysis patients with anuria and that gastrointestinal symptoms can be the primary indicators of systemic amyloidosis. Endoscopic examination including biopsy is important for the diagnosis and early treatment of amyloidosis.

AA Amyloidosis associated with cancers

Systemic AA amyloidosis is associated with systemic inflammatory processes such as autoimmune disorders or chronic infections. In addition, AA amyloidosis can develop in a localized or systemic form in patients with malignant neoplastic disorders, and usually involves kidneys impacting renal function. Among solid tumors, renal cell carcinoma (RCC) appears to be responsible for one-quarter to half of all cancers associated with amyloidosis. Among other solid cancers, various clinical presentation and pathological types of lung cancer and basal cell carcinoma skin were reported with AA amyloidosis more often than isolated case reports on other cancers with AA amyloidosis. Symptoms from kidney involvement rather than from the tumor per se were the presenting manifestations in cases of RCC associated with AA amyloidosis. Among hematological malignancies, clonal B cell/plasma cell dyscrasias such as monoclonal gammopathy and lymphoma were noted to be associated with AA amyloidosis. In addition, AA amyloidosis was reported in a substantial number of cases treated with immune checkpoint inhibitors such as pembrolizumab and nivolumab. The mechanism of association of cancer and AA amyloidosis seems to be mediated by the immune response exacerbated from the tumor and its microenvironment or immune therapy. The mainstay of treatment consists of therapy directed against the underlying malignancy or careful withdrawal of the offending agent. This review will discuss this rare but highly morbid clinical condition.

Advanced systemic amyloidosis secondary to metastatic renal cell carcinoma

Secondary amyloidosis is a rare complex complication related to chronic inflammatory disease. This complication is sparsely associated to malignant neoplasms. Renal cell carcinoma (RCC) is the most common solid organ malignancy related with this paraneoplastic syndrome. Some case reports have described stabilisation or even remission of amyloidosis with cytoreductive nephrectomy. Majority of those reports were based on locally advanced RCC. We report the first case of early aggressive systemic secondary amyloidosis in high-volume metastatic RCC. The subject was diagnosed with metastatic RCC within 6 months of secondary amyloidosis; on month 5 of initiation of targeted therapy (pazopanib) developed nephrotic syndrome with a heavy proteinuria (>18 g/day), severe hypoalbuminaemia (1.53 g/dL), intense and progressive oedema, severe pancolitis and mild dyspnoea with hypotension. A colon biopsy and the immunohistochemistry confirmed the histological diagnosis of a secondary amyloidosis. The multidisciplinary tumour board decided to perform cytoreductive nephrectomy in order to reduce the pro-inflammatory status. Pathology report showed a complete resection of clear cell RCC plus renal amyloid deposits. The patient died within 4 days of surgery due to multiorgan failure.

Cervical cancer of the uterus complicated by renal AA amyloidosis

Cervical cancer of the uterus rarely develops systemic secondary amyloidosis. We present the case of a 66-year-old female patient who manifested systemic amyloid A (AA) amyloidosis in the kidney, digestive tract, and cervix of the uterus, secondary to cervical cancer. She exhibited nephrotic syndrome, intractable diarrhea, and mild fever 3 months after she underwent an extended hysterectomy with postoperative cisplatin-based chemotherapy and whole pelvic irradiation. Further examinations revealed AA amyloidosis of the kidney and colon and cytomegalovirus infection in the colon. AA amyloid deposition was positive in the resected tissues of uterine cancer. The patient was diagnosed with systemic AA amyloidosis consecutive to cervical cancer. Despite a decrease in urinary protein after antiviral therapy, it increased 14 months later with neither apparent symptoms nor an increase in tumor marker. A second renal biopsy revealed AA amyloidosis of the kidney. Subsequent investigations revealed the recurrence of cervical cancer in the lung, liver, and lymph nodes. This case report indicated that AA amyloidosis would complicate cervical cancer and recur even after resection of neoplasm owing to other stimulation. Moreover, urine protein could be a marker for cancer relapse in known cases of cancer-derived AA amyloidosis.

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

Renal cell carcinoma accounts for approximately 3% of adult malignancies. Designated in the literature as "the great masquerader," the great diversity of clinical manifestations is associated with the several paraneoplastic syndromes that potentially accompany it. Paraneoplastic amyloidosis is described in about 3-8% of cases, only exceptionally as an initial manifestation, with uncommon gastrointestinal involvement. A rare case of malabsorption by intestinal amyloidosis is presented as initial manifestation of renal cell carcinoma, emphasizing the need for early recognition of these paraneoplastic conditions.

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

Background

Amyloid A amyloidosis is one of the most common forms of amyloidosis. It is secondary to rheumatoid arthritis, which is difficult to manage and has a poor prognosis. We present a patient with rheumatoid arthritis and amyloid A amyloidosis who was treated with tocilizumab, a humanized monoclonal antibody against interleukin 6 receptor, resulting in improvement in both proteinuria and gastrointestinal symptoms; however, amyloid deposition remained.

Case presentation

A 67-year-old woman who had previously been treated for rheumatoid arthritis presented with abdominal pain and diarrhea. Right renal cell carcinoma was found, and amyloid A amyloidosis was diagnosed concomitantly based on colon biopsy. The renal cell carcinoma was resected, and the non-cancerous part of the renal tissue also showed amyloid A deposition. Following surgery, protein levels in the urine increased to the nephrotic range, and administration of tocilizumab was initiated, which resulted in resolution of the proteinuria. The patient’s gastrointestinal symptoms were also alleviated. However, repeat colon biopsy showed amyloid deposition.

Conclusions

This case of amyloid A amyloidosis suggests that amyloid deposition indicates only structural change of the affected tissue, and that it is not amyloid deposition per se that causes the clinical symptoms of amyloidosis.