Broccoli sulforaphane inhibits breast cancer stem cells

The authors of this study just published in the journal Clinical Cancer Research begin their report by noting:"The existence of cancer stem cells (CSCs) in breast cancer has profound implications for cancer prevention. In this study, we evaluated sulforaphane, a natural compound derived from broccoli/broccoli sprouts, for its efficacy to inhibit breast CSCs and its potential mechanism."Their data showed a marked decrease in breast cancer stem cells in vivo,

"...thereby abrogating tumor growth after the reimplantation of primary tumor cells into the secondary mice."

Their conclusion:

"Sulforaphane inhibits breast CSCs and downregulates the Wnt/β-catenin self-renewal pathway. These findings support the use of sulforaphane for the chemoprevention of breast cancer stem cells and warrant further clinical evaluation."

Of course this is not the same as a full-blown study on sulforaphane as a treatment for breast cancer; but why not add broccoli and broccoli sprouts (if not one of the more concentrated preparations) to the diet?