Cancer mortality in a region with endemic nephropathy

Cancer mortality in endemic and non-endemic villages from a region with endemic nephropathy (EN) of Vratza district, Bulgaria has been compared for the period 1965--1974. The total and for all cancer sites mortality rates in all studied villages were comparable to European and world standards except a very high mortality from tumors of urinary organs in the endemic villages. Age-adjusted to world population rates/10(5) population in hyperendemic villages have been estimated as 16.8 for males and 14.9 for females in case of kidney tumors and as 7.1 in males and 10.2 for females in case of urinary bladder tumors. On village group basis a very close correlation between mortality rates from urinary system tumors and EN incidence rates has been disclosed although endemic and non-endemic villages are neighbouring and are very similar in ecological and cultural terms.