Tamoxifen in women with breast cancer and mammographic density

Purpose of investigation: To evaluate the effect of tamoxifen on mammographic density using a qualitative and a semiquantitative method. Methods: Mammograms from 148 women treated for breast cancer before and after surgery were reviewed: 68 were administered tamoxifen: 80 did not receive tamoxifen. The mammograms were classified in one of the four BIRADS density categories by two radiologists blinded to the treatment and by a computer-assisted method after digitizing images. Results: At mammographic one-year-follow-up density was reduced in both groups and remained stable in the following years. A comparison of mammograms performed before surgery and after one year showed a statistically significant difference in density reduction between the tamoxifen and the non-tamoxifen-treated group. Good agreement was obtained between the qualitative and semiquantitative method. Conclusion: Breast density reduction observed in women treated with tamoxifen may help in the detection of small tumors in dense breasts by means of reducing the masking effect of parenchyma.

Mammographic density; Breast cancer; Tamoxifen

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