Pizza has been favourably related to the risk of prostate cancer in North America. Scanty information, however, is available on sex hormone-related cancer sites. We therefore studied the role of pizza consumption on the risk of breast, ovarian and prostate cancers using data from three hospital-based case-control studies conducted in Italy between 1991 and 2002. These included 2569 women with breast cancer, 1031 with ovarian cancer, 1294 men with prostate cancer, and a total of 4864 controls. Compared with non-pizza eaters, the multivariate odds ratios for eaters were 0.97 (95% confidence interval (CI) 0.86-1.10) for breast, 1.06 (95% CI 0.89-1.26) for ovarian and 1.04 (95% CI 0.88-1.23) for prostate cancer. Corresponding estimates for regular eaters (i.e. > or =1 portion per week) were 0.92 (95% CI 0.78-1.08), 1.00 (95% CI 0.80-1.25) and 1.12 (95% CI 0.88-1.43), respectively. Our results do not show a relevant role of pizza on the risk of sex hormone-related cancers. The difference with selected studies from North America suggests that dietary and lifestyle correlates of pizza eating vary between different populations and social groups.