There are more references going back to Beatson (1890s) and Loeser (1950s) in the Lancet. Giving Breast Cancer patients dessicated thyroid enhanced their survival. Loeser found removing the ovaries stimulated the thyroid to produce more thyroid hormones. He felt Breast Cancer patients should be kept a little hyperthyroid.
My sense, and Eskin shares this, is that thyroid disease does not directly cause breast disease. But both breast and thyroid seem to share a parallel need for Iodine and compete for Iodine in the blood. Thus, before iodized salt in the US, midwest girls began to get goiter at puberty when their bodies needed to supply additional Iodine to developing organs (breast and ovaries. Boys did not get goiter as frequently. Dr. Brownstein may describe this phenomenon in his book-- the part leading up to the iodization of salt.
Also, a reason not to suppress the thyroid is that thyroidectomy raises the risk of Breast Cancer hugely. We need those hormones. So my research leads me to observe that swatting the estrogen in the breast with concentrated brassica pills has collateral damage in suppressing the thyroid which boomerangs back to denying the breast the benefits of thyroxine.
In the video on Indonesian iodine difficiency, the doctor goes into the schools to feel the pubescent girls' thyroids. Many have beginning goiters. Then he goes to houses and find the girls' mothers have bought counterfeit iodized salt. Indonesia has rich soil-- but very iodine deficient.