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.

Summary Verrucous carcinoma is a rare skin malignancy of squamous cell origin. It is characterised by negligible cellular atypia and a low mitotic rate. These are reflected in slow locally invasive behaviour and very infrequent metastatic spread. The tumour is also recognised in oral and anogenital sites. Cutaneous lesions present most commonly on the sole of the foot. We report a unique case occurring in the female breast.