The incidence of female cancers: correlations with etiologic implications.

Correlation coefficients were calculated between incidence rates for the most frequent female cancers in populations throughout the world. Positive correlations were generally weak, and we conclude that most female cancers do not share a dominant etiologic factor which is inherent in cancer incidence rates. However, most cancers do exhibit similar age-incidence patterns. We also conclude that the determinant of shape in cancer age-incidence patterns is common to most female cancers, internationally invariant, and independent of the determinants of cancer incidence rates. Breast cancer exhibits an unusual age-incidence pattern with a peculiar dependence on the frequency of breast cancer occurrence.