Nephrogenic adenoma, also mesonephric adenoma and nephrogenic metaplasia, is a benign

Benign

A benign tumor is a tumor that lacks the ability to metastasize. Common examples of benign tumors include moles and uterine fibroids.The term "benign" implies a mild and nonprogressive disease. Indeed, many kinds of benign tumors are harmless to human health...

 growth typically found in the urinary bladder

Urinary bladder

The urinary bladder is the organ that collects urine excreted by the kidneys before disposal by urination. A hollow muscular, and distensible organ, the bladder sits on the pelvic floor...

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It is thought to result from displacement and implantation of renal tubular cells, as this entity in kidney transplant recipients has been shown to be kidney donor derived.

This entity should not be confused with the similar sounding metanephric adenoma

Metanephric adenoma

Metanephric adenoma is a rare, benign tumour of the kidney, that can have a microscopic appearance similar to a nephroblastoma , or a papillary renal cell carcinoma....

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Diagnosis

Nephrogenic adenomas are diagnosed on biopsy, by their appearance under the microscope

Microscope

A microscope is an instrument used to see objects that are too small for the naked eye. The science of investigating small objects using such an instrument is called microscopy...

, by pathologists.