Avocados are pear-shaped berries with green spiny skin and a solid pit in the middle. They have been long implemented as a factor in a healthy ratio of blood lipid profiles and enhancing the bioavailability of fat soluble vitamins, but most recently they have been studied for their anti-cancer effects. Persin is a fungicidal toxin present in several parts of the avocado; the bark of the tree, the seeds, and most commonly the leaves. It is active at low micro-molar concentrations against breast cancer cells and synergizes with the estrogen receptor modulator 4-hydroxytamoxifen (Brooke et al., 2011) . The benefits of Tamoxifen alone in breast cancer have been studied generously. The addition of Persin is of interest because this combination has been shown to transcriptionally down regulate estrogen receptor expression in breast cancer cells and effectively promote apoptosis in estrogen receptor negative breast cancer cells (Roberts, Gurisik, Biden, Sutherland, & Butt, 2007). Microtubules play an important role in the effectiveness of persin while tamoxifen binds to HER2 (Field et al., 2016). This article is a comprehensive review of what is currently known about persin's function as a microtubule stabilizer and its relationship with tamoxifen within breast cancer.