Talc and anti-MUC1 antibodies.

To the Editors: Cramer et al. (1) present very intriguing findings on anti-MUC1 antibodies and their relationship to ovarian cancer risk factors in healthy women, raising new theories on the role of immunity in ovarian cancer and opening up avenues for new research in this area. The analysis is straightforward, yet the conclusion about genital talc exposure increasing ovarian cancer risk via diminished antibody levels is not supported by their own data. Talc exposure was characterized as ‘‘none,’’ ‘‘body use only,’’ and ‘‘genital use.’’ Antibody levels were appropriately classified as ‘‘negative,’’ ‘‘low,’’ ‘‘intermediate,’’ and ‘‘high.’’ The overall unadjusted m P value is 0.01 but an analysis limited to none and body use only yields a strong association as well (P = 0.09). The genital use group had significantly lower intermediate levels of antibodies than the none group but an analysis of the body use only group also shows a significantly lower intermediate levels than the none group (P = 0.01). There is no biological expectation that using powder on the armpits or other skin surfaces above the perineum would affect MUC1 expression. Similarly, it seems highly unlikely that talc exposure on the superficial layers of female genitals could indirectly cause ovarian cancer by reducing antibodies. Talc from genital dusting could translocate to the ovaries but this speculative assumption was ruled out years ago by electron microscopy studies showing no relationship between genital dusting and ovarian talc particle concentrations (2).