Epidemiology of cancer in children under one year of age in Mexico City.

In this work, the epidemiology of cancer in children under one year of age in Mexico City is described. A survey (observational, descriptive and prolective study) from 1 January 1996 to 31 December 1999 was conducted at two paediatric hospitals of the Instituto Mexicano de Seguro Social in Mexico City (IMSS-MC). To calculate both the general and the by sex incidence (rates are given per 10) all new cases recorded for children under one year of age (numerator) and Mexico City population served by the IMSS (denominator) were used. When the total of 34 cases that fulfilled the requirements was analysed, an incidence of 194.5 was obtained. Leukaemia occupied first place with a rate of 68.6 and hepatic and germinal cells tumours occupied second place with an incidence of 28.6, whereas peripheral nervous system tumours (neuroblastoma) showed a very low rate (11.4). Overall, the male/female ratio for tumours was 1.4:1, with the ratio varying with different types of tumours. Cancer incidence in this population was shown to be close to that in developed countries, but differed in the distribution of the type of tumour: leukaemia had a very high incidence and that for neuroblastoma was very low.