The Pathology of Tumours of the Urinary Tract: (Section of Radiology).

Attention is called to the difference between the pathologist's and the radiologist's point of view. The reasons for this difference are discussed with special emphasis on renal tumours.Classification of renal tumours. The first main groups are innocent and malignant. Are these really clear-cut or do they blend into one another? The commoner innocent renal tumours are adenoma, fibroma, myoma, lipoma, and angioma. These are rarely of any clinical importance but adenoma is a possible source of hypernephroma. Many elaborate classifications of cancer of the kidney have been proposed but the following four groups are sufficient for most puposes: Carcinoma, hypernephroma, sarcoma, and teratoid tumours.Much the commonest malignant renal tumour in adults is the hypernephroma, thought by Grawitz and others to be derived from ectopic adrenal rests. There is still no agreement concerning their origin but three views are held at the present time: (a) All are carcinoma of renal tubules. (b) Some are derived from renal tubules and some from ectopic adrenal. (c) All are formed from adrenal tissue. These views are discussed with special reference to material in St. Mary's Hospital Museum, and it is suggested that the first view is the most probable although the second cannot be excluded.The teratoid tumours are the commonest in infants and swine. The differences between them and hypernephromata are described. The renal Pelvis, ureter, and bladder all have tumours of the same type and can conveniently be considered together. Connective tissue tumours, both innocent and malignant, are very rare. Papilloma and carcinoma are rare in the pelvis and ureter, but commoner in the bladder. The relation between these two tumours is discussed.