Renal Squamous Cell Carcinoma-related Polymyositis in a Patient with Autosomal Dominant Polycystic Kidney Disease

Abstract

A 74-year-old Japanese woman diagnosed with autosomal dominant polycystic kidney disease (ADPKD) was admitted to our institute for the further examination of right-side groin pain developing in the past week. The patient was diagnosed with polymyositis (PM). Diagnostic imaging showed a mass lesion measuring 8 cm and a renal stone in the right kidney. Immediately following surgical resection of the right kidney, the patient's serum CK decreased to the normal range. A histopathological analysis showed well-differentiated squamous cell carcinoma. In conclusion, this case showed a close relationship between the occurrence of squamous cell carcinoma and the development of PM in an ADPKD patient.

Paraneoplastic Polymyositis Due to Renal Cell Carcinoma in a Patient with Autosomal Dominant Polycystic Kidney Disease

“…Immediately after surgical resection of the right kidney, the patient's serum CK level decreased to within the normal range. These authors hypothesized that the occurrence of squamous cell carcinoma in patients with ADPKD is closely related to the development of polymyositis ( 10 ). Although there have been some reports describing other types of myositis related to RCC ( 8 , 9 ), these are the only reports of polymyositis with RCC as a paraneoplastic syndrome.…”

“…When we focused on instances of myositis related to RCC accompanied by polycystic kidney disease, the case reported by Terakawa et al was the only one previously published ( 10 ). Although only a few reports have been published concerning myositis associated with RCC, patients with ADPKD have an increased risk of renal carcinoma ( 1 ), so we should consider the possibility of RCC with paraneoplastic myositis if those patients develop muscle weakness.…”