Increased incidence of renal parenchymal carcinoma in the Northern and Yorkshire region of England, 1978-1997.

Kidney cancer remains relatively rare, but incidence and mortality rates are reported to be rising steadily across the world. To determine if such increases were occurring in the UK, we examined the rates of incidence and mortality in different histological subtypes of kidney cancer in the Northern and Yorkshire region of England. Details of all 8741 cases diagnosed between 1978 and 1997 were extracted from the population-based Northern and Yorkshire Cancer Registry. For all types of tumour, both incidence and mortality rates increased over the study period. Overall age-standardised incidence rates increased by 86% for renal parenchymal carcinoma (RPC) (80% for males, 90% for females) from 2.8 to 5.2 cases per 100000 (3.8-6.8 male, 2.0-3.8 female). There were incidence increases in all age groups, all Carstairs index groups and in both urban and rural populations. Although increased incidental detection of kidney tumours by improved investigational techniques may account for some of this rise, we believe it unlikely that it accounts for all of the increase observed. Potential aetiological causes for the increased rates include hypertension, smoking, a diet lacking fruit and vegetables, analgesic use and, particularly, obesity.