Data from 10 Italian population-based cancer registries were used to estimate the prevalence of female tumors of the breast and genital tract. The total prevalence, expressed in number per 100,000, was highest for breast cancer (1,117), followed by cancer of the corpus (264) and cervix uteri (146), ovary (110), and vagina and vulva (23). For all tumors the prevalence increased with age at diagnosis. The cancer prevalence was divided into intervals from diagnosis, expressing different health needs in terms of therapy and intensity of clinical follow-up. For all tumors considered, 1-year prevalence was higher than 1-2-year prevalence, reflecting a high death risk due to perioperative mortality and to the proportion of patients diagnosed at advanced stages. The prevalence decreased in the following intervals considered. Noticeable geographic variability was observed in the prevalence across Italy, with higher proportions being registered in the northern-central regions than in the South. The two extreme 0-5-year prevalence figures (per 100,000) were: for breast cancer 568 (Genova) and 259 (Ragusa); for corpus uteri cancer 94 (Romagna) and 21 (Latina); for cervix uteri cancer 63 (Romagna) and 26 (Latina); for ovarian cancer 49 (Parma) and 21 (Latina); for cancer of the vagina and vulva 17 (Genova) and 5 (Ragusa). This variability depends mainly on incidence and on the proportion of elderly in the general population. From 1987 to 1992 there was an increase in the prevalence of tumors of the breast, ovary and vagina and vulva, especially in the elderly. The prevalence of corpus uteri cancer decreased slightly in the elderly only, whereas that of cervix uteri cancer decreased at all ages.