Eosinophilic solid and cystic renal cell carcinoma – an emerging renal tumour with a good prognosis

Abstract

Eosinophilic solid and cystic renal cell carcinoma is an uncommon, recently recognised, malignant renal tumour that has distinctive pathological and genetic features. This tumour enters into the histological differential diagnosis of a renal tumour with eosinophilic cytoplasm. It is important to recognise because it has a generally favourable prognosis and may prompt genetic testing due to its association with mutations in the tuberous sclerosis complex genes. We present two cases of renal carcinoma, occurring in a 19-year-old man and a 42-year-old woman, both discovered incidentally, showing similar pathological features and having low stage disease. The purpose of this report is to increase awareness of this uncommon renal tumour, to aid in its recognition by pathologists and to alert treating clinicians to its typically indolent behaviour and genetic associations.